Bahir Dar University College of Agricutlure and Environmental Sciences Graduate Program

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BAHIR DAR UNIVERSITY COLLEGE OF AGRICUTLURE AND ENVIRONMENTAL SCIENCES GRADUATE PROGRAM

ASSESSMENT OF ONION PRODUCTION PRACTICES AND EFFECTS OF

N:P2O5:S FERTILIZERS RATES ON YIELD AND YIELD COMPONENTS OF ONION (ALLIUM CEPA L.) UNDER IRRIGATED FARMING SYSTEM IN DEMBIYA DISTRICT, AMHARA REGION, ETHIOPIA

M.Sc. Thesis By

Muluneh Nigatu Yosef

March 2016 Bahir Dar, Ethiopia

BAHIR DAR UNIVERSITY COLLEGE OF AGRICUTLURE AND ENVIRONMENTAL SCIENCES GRADUATE PROGRAM

ASSESSMENT OF ONION PRODUCTION PRACTICES AND EFFECTS OF

N:P2O5:S FERTILIZERS RATES ON YIELD AND YIELD COMPONENTS OF ONION (ALLIUM CEPA L.) UNDER IRRIGATED FARMING SYSTEM IN DEMBIYA DISTRICT, AMHARA REGION, ETHIOPIA

M.Sc. Thesis By Muluneh Nigatu Yosef

Submitted In Partial Fulfillment of the Requirements for the Degree of Master of Science (M.Sc.) in “Horticulture”

Major Advisor: Dr. Melkamu Alemayehu Co-Advisor: Dr. Amare H/Silassie

March, 2016 Bahir Dar, Ethiopia

THESIS APPROVAL SHEET

As member of board of examiner of Master of Science thesis open defense examination. We have read and evaluated this thesis prepared by Mr. Muluneh Nigatu Yosef entitled

“Assessment of onion Production Practices and Effects N:P2O5:S Fertilizer Rates on Yield and yield components of Onion (Allium Cepa L.) under Irrigated Farming System in Dembyia District, Amhara Region, Ethiopia.” We here by certify that, the thesis is accepted for fulfilling the requirement of the award of Master of Science (M.Sc.) in HORTICULTURE

Board of Examiners 1. ------Name of external examiner Signature Date

2. ------Name of Internal examiner Signature Date

3. ------Name of chairman Signature Date

DECLARATION

This is to certify that this thesis entitled “Assessment of onion Production Practices and

Effects of N:P2O5:S Fertilizer Rates on Yield and Yield Components of Onion (Allium Cepa L.) under Irrigated Farming System in Dembyia District, Amhara Region, Ethiopia.” submitted in partial fulfillment of the requirements for the award of the degree of Master of Science in Horticulture to the Graduate Program of College of Agriculture and Environmental Sciences, Bahir Dar University by Mr. Muluneh Nigatu (ID. No. BDU 40602060PR) is an authentic work carried out by him under our guidance. The matter embodied in this project work has not been submitted earlier for award of any degree or diploma to the best of our knowledge and belief.

Name of the Student ______Signature & date ______

Name of the Supervisors 1) ______(Major Supervisor)

Signature & date______

2) ______(Co-Supervisor) Signature & date ______

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ACKNOWLEDGEMENT

I would like to express my profound thanks to the Almighty God for helping and providing all I needed to make this research project possible.

I am greatly indebted to my major advisor, Dr Melkamu Alemayehu for his valuable advice, right direction from the proposal development, field supervision in my research area, constructive comments and guidance that made this works a success.

I am very grateful to my co-advisor, Dr Amare Haileslassie which was his excellent guidance and assistance from the very beginning of the proposal initiation up to the final thesis work. I would like also to express my sincere gratitude to the (LIVES), a project led by the International Livestock Research Institute and International Water Management Institute, for providing the funding for tuition fee, research and other expenses.

My gratitude goes to all the senior members’ staff of Gondar research center, especially Dr Abrham Abiyu, Mr. Yismaw Degnet and Ertiban Wondifraw for their special assistance and contribution in diverse ways towards the successful completion of this work.

I am grateful to Mr. Agegnehu Shibabaw, Maru Nigussu, Tesfaye Nigussu, Amanuel Ferede and Yalew Tizazu for their support and encouragement.

Finally, my deepest gratitude goes to my wife Tadila Haile and my daughter Semariya Muluneh for their prayers, support and encouragement.

DEDICATION

The author dedicates this thesis to his lovely daughter Semariya Muluneh.

ABBREVIATIONS AND ACRONYMS

ANOVA Analysis of Variance BoFED Bureau of Finance and Economic Development Br Bombay Red C: N Carbon to Nitrogen ratio CEC Cation Exchange Capacity CSA Central Statistical Agency CAES College of Agriculture and Environmental Sciences CEC Cation exchange capacity CV Coefficient of Variation DMRT Duncan’s Multiple Range Test DWRDAPO Dembiya Woreda Rural Development and Agricultural Planning Office E East EIA Ethiopian Investment Agency EIAR Ethiopian Institute of Agricultural Research ET-FRUIT Ethiopian Fruit and Vegetable Marketing Enterprise FAO Food and Agriculture Organization FYM Farm yard manure Ha Hectare HH Household Head M.A.S.L Meters above sea level MoARD Ministry of Agriculture and Rural Development N North NGOs Non Governmental Organizations PH Power of hydrogen

NPS N:P2O5:S RCBD Randomized Complete Block Design RDA Rural Development Administration SAS Statistical Analysis System SPSS Statistical Package for Social Sciences T Ton

ASSESSMENT OF ONION PRODUCTION PRACTICES AND EFFECTS OF N: P2O5:S FERTILIZER RATES ON YIELD AND YIELD COMPONENTS OF ONION (Allium cepa L) UNDER IRRIGATED FARMING SYSTEM IN DEMBYIA DISTRICT, ETHIOPIA By Muluneh Nigatu Major advisor: Dr. Melkamu Alemayehu and Co advisor: Dr. Amare Haileslassie ABSTRACT

The study was initiated with assessing onion production practices and effects of N: P2O5:S, fertilizer rates on yield of Onion (Allium Cepa L.) under irrigated farming system in Dembyia, District, Amhara Region, Ethiopia. The work has two components namely assessing onion production practices in Sufankara, Guramba and Debir zuria kebeles and evaluating the effects of N: P2O5:S, fertilizer rates on yield and yield components of onion in Jenda kebele. The study was conducted during 2014/15 under irrigation. To assess onion production practices data was collected from 30 onion producing households using semi-structured questioners, focus group discussions, data on demographic structure and the whole value chain of onion production system were recorded and analyzed using SPSS version 20. In the experimental part twelve different N: P2O5:S fertilizer rates were tested. The experiment was laid down in randomized complete block design (RCBD) with three replications. Data on vegetative and yield parameters were collected and analyzed using SAS version 9.0 computer soft ware. The survey result indicated that most of the onion producers in the study area did not implemented the recommended irrigation cultural practices of onion, Limited supply of improved onion seeds also one of the important factor that contributes to low productivities of onion in the study area. Low rates of fertilizers application, low population of onion plants per unit area, high incidence of disease and insect pests, shortage of pesticides and their adulteration characterize the onion production system under farmer’s practice. As a result the productivity of onion under farmers was low (85.6q/ha) compared with the national production (101q/ha). Besides the average crop water productivity was (1.74 kg/m3) which were relatively low with compared to other researches on onion crop water productivity (4.62 kg/m3)). Although the quantity of water is similar with the requirement of onion (4,914 m3/ha), but the yield obtained is low. The major constraints of onion production in the study area were shortage of irrigation water, high costs of irrigation equipments, shortage of genuine spare parts and accessories, shortage of pesticides and their adulteration, limited supply of improved onion seeds and lack of storage facilities, lack of skills and knowledge, high incidence of diseases and insect pests and weak extension and credit services. Results of N: P2O5:S, rate trial revealed that most of growth and yield parameters of onion were significantly influenced by N: P2O5:S fertilizer rates. The highest plant height (60.1 cm), leaf length (50.1cm) and maturity days (142 -1 days) were recorded in 73.5:92:16.95, 136.5:119.6:22 and 136.5:119.6:22 kg ha N: P2O5: S, application rates respectively. The highest bulb weight (198.8g), marketable yield (20.8t/ha), non marketable yields (0.509 t/ha) and total bulb yield (21.398t/ha) were recorded offer 105:119.6:22 -1 kg ha N:P2O5:S application rate . Onion plants without N: P2O5:S, fertilizer applications were inferior in all growth and yield parameters. For enhancement of production and productivity of onion in Dembyia district and other similar environment, it is necessary to solve problems indicated above through training, extension activities and improving the supply of inputs. -1 Application of N: P2O5:S fertilizer at the rate of 105:119.6:22 N:P2O5:S kg ha was economically feasible and thus can be recommended for the production of onion in the study area. However is advised to repeat the experiment to have forceful recommendation

Keywords: Onion, fertilizer rate, N: P2O5:S, vegetative growth, bulb yield

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TABLE OF CONTENTS

THESIS APPROVAL SHEET ...... ii

DECLARATION ...... iii

ACKNOWLEDGEMENT ...... iv

DEDICATION ...... v

ABBREVIATIONS AND ACRONYMS ...... vi

ABSTRACT ...... vii

TABLE OF CONTENTS ...... viii

LIST OF TABLES ...... x

LIST OF FIGURES ...... xi

LIST OF APPENDIX TABLES ...... xii

CHAPTER 1: INTRODUCTION ...... 1

1.1. Background and Justification ...... 1 1.2. Objectives of the Study ...... 3 General Objective ...... 3 Specific Objectives ...... 3 CHAPTER 2: LITERATURE REVIEW ...... 4

2.1. Botany and Origin ...... 4 2.2. Distribution and Importance of Onion ...... 4 2.3. Soil and climatic requirement of Onion ...... 5 2.4. Farmer`s Onion Production Practices in Ethiopia ...... 6 2.5. Potentials and Constraints of Onion Production in Ethiopia ...... 8 2.6. Response of Onion to Inorganic and Organic Fertilizers ...... 9 CHAPTER 3: MATERIAL AND METHODS ...... 14

3.1 Description of the Study Area ...... 14 3.2 Assessment of Production Practices of Onion...... 15 3.2.1. Sampling procedure ...... 15 3.2.2. Data collection and analysis ...... 15 3.2.3. Irrigation water measurement and procedure ...... 16

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TABLE OF CONTENTS Continued

3.3. Effects of Different Rates of N: P2O5:S Fertilizer on Yield and Yield Components of Onion ...... 17 3.3.1. Treatments and experimental design ...... 17 3.3.2. Management of the experimental plots ...... 18 3.3.3. Data collection ...... 19 3.3.4. Data Analysis ...... 21 CHAPTER 4: RESULTS AND DISCUSSIONS ...... 22

4.1 Assessment of Onion Production Practices ...... 22 4.1.1 Demographic characteristics the respondents ...... 22 Landholdings of the respondents ...... 24 4.1.2. Raising and transplanting of onion seedlings...... 25 4.1.3. Onion production and harvesting practices in the study area ...... 28

4.2. Effects of N:P2O5:S Fertilizers on Yield and Yield Components of Onion ...... 39 4.2.1 Vegetative growth parameters of onion ...... 40 4.2.2. Yield and yield parameters of onion ...... 42

4.2.3. Marginal rate of return of onion as affected by N: P2O5:S fertilizer rates .... 45 CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS ...... 48

5.1. Conclusions ...... 48 5.2. Recommendations ...... 50 6. REFERENCES ...... 51

APPENDIX ...... 62

ANNEX ...... 66

BIOGRAPHIC SKETCH ...... 71

LIST OF TABLES

Table Pages Table 3.1. Experimental treatments used in the study area ...... 17 Table 4.1 Sex, age, marital status and family size of respondent in the study area ...... 23 Table 4.2. Land allocation of the respondents in the study area ...... 25 Table 4.3.source of seeds, varieties used, growing season of onion in the study area ...... 26 Table 4.4. Age, spacing and time of ttransplanting of onion seedlings in the study area ... 27 Table 4.5. Inorganic fertilizers used and their methods and time application in the study area ...... 29 Table 4.6. Organic fertilizers used and their methods and time application in the study area in the study area ...... 30 Table 4.7. Sources, methods and frequency of irrigation in the study area ...... 32 Table 4.8. Major pests and their management in the study area ...... 33 Table 4.9. Onion maturity indices and harvesting methods used in the study area ...... 35 Table 4.10. Postharvest handling and marketing of onion in the study area ...... 36 Table 4.11. Storage methods and length of storage used in the study area ...... 37 Table 4.12. Onion and water productivity in the study area ...... 38 Table 4.13.Analysis results of the experimental soil ...... 39

Table 4.14. The vegetative growth of onion as influenced by different N:P2O5:S rates..... 42

Table 4.15.Yield parameters of onion as influenced by different N:P2O5:S rates ...... 45

Table 4.16. Cost gross income and net profit of onion as influenced by N: P2O5:S fertilizer rates in Dembyia District ...... 46

Table 4.17. Marginal rate of return (MRR) of N: P2O5:S fertilizer rates in Dembyia District ...... 47

LIST OF FIGURES

Figure Page 3.1. Map of the study area ...... 15 3.2. Lay out of field experiment ...... 18 4.1. Educational status of the respondents in the study area ...... 24 4.2. Irrigation experience of the respondents in the study area ...... 31 4.3. Length of maturity of onion in the study area...... 34

LIST OF APPENDIX TABLES

Appendix Table Pages

1. ANOVA Table for plant height...... 63 2. ANOVA Table for leaf length...... 63 3. ANOVA Table for leaf diameter...... 63 4. ANOVA Table for date of maturity ...... 64 5. ANOVA Table for bulb weight...... 64 6. ANOVA Table for marketable bulb yield ...... 64 7. ANOVA Table for unmarketable bulb yield ...... 65 8. ANOVA Table for total bulb yield ...... 65

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CHAPTER 1: INTRODUCTION

1.1. Background and Justification

Onion (Allium cepa L.), also known as the bulb onion and common onion, is the most widely cultivated species of the genus Allium, and belongs to the family Alliaceae (Hanelt, 1990). Onion is one of the most important monocotyledonous, cross-pollinated and cool season bulb vegetable crops produced throughout the world (Tindall, 1983). It is grown in more than 130 countries in the world. China and India are the world’s largest producers of onion, followed by USA, Netherland, Egypt and, Iran (FAOSTAT, 2014).

Onion is widely used as a condiment to enhance the flavor of food. Almost all spicy dishes contain onion as one of the important ingredient used for culinary purposes. People consider it as an indispensable part of human diet. It is a rich source of several minerals and vitamins (Tindal, 1983, Raemaekers, 2001). Onion is also considerably important in the daily Ethiopian diet for the preparation of traditional foods. Some of the plant parts are edible, the bulbs and the lower section of stem are the most popular as a seasoning or a vegetable in stews (MoARD, 2005).

Onion has also a long history of medicinal importance. Compounds from onion have been reported to have a range of health benefits which include anticarcenogenic properties, anti platelet activity, antithrombotic activity, asthmatic and antibiotic effects and effective against the common cold, heart disease, diabetes, osteoporosis, and other diseases (Griffiths et al., 2002).

Onions can be grown under a wide range of climatic conditions. However, their production is more successful under mild climate without extremes of heat or cold and excessive rainfall (Lemma, 2004).

Ethiopia’s diversified agro-climatic conditions suitable for the production of a broad range of fruits, vegetables and flowers also allow successful production of onion (Lemma et al., 2006). Currently, onion is an important cash crop for Ethiopian farmers hence the crop is produced in different parts of the country for local consumption and for regional export market (MoARD, 2005). However, the best growing altitude for onions under Ethiopian condition is between 700 and 1800 m above sea level (Lemma, 2004).

Onion is predominantly produced by Ethiopian smallholder farmers in high and mid- altitude areas mostly using traditional production system (Kubsa et al. 2006). According to (CSA, 2014) the average annual production of onion is about 230,745.2 tons produced on 24, 375.7 hectares of land. About 705,877 households are participated in the production of onion in the country. Its production is likely increasing in the near future because of the expansion of irrigable areas (MoARD, 2005). Annual per capita consumption of different vegetables in Ethiopia is 5.8 kg and out of which onion consumption is 1.7 kg per capita (CSA, 2005).

The production and productivity of vegetables in general and onion in Ethiopia is very low compared to the potentials the country has. Their production is facing various problems which contribute to this low level of production and productivity. Among various constraints lack of appropriate agronomic packages, shortage of seeds of improved varieties, diseases, insect pests and poor extension services, high costs of chemical fertilizers and sometimes unavailable to small scale farmers (Currah and Proctor, 1990, Melkamu Alemayehu et al., 2015).

As shallow rooted vegetables onion requires relatively high level of soil fertility to support high yield. Although the fertilizer requirement of a crop depends on the type of crop produced, the fertility status of the soil, and the environmental conditions of the area, onion growers in Ethiopia including those in Dembyia District use a blanket recommendation of 200 kg/ha DAP and 150 kg/ha urea as a source of phosphorus and nitrogen, respectively which may not satisfy the nutrient requirements of onion plant Murphy (1968). For that reason, the Ministry of Agriculture has currently introduced a new fertilizer (N:P2O5:S) that contains nitrogen, phosphorous and sulfur with the concentration of 19%, 38%, and 7%, respectively. According to the Ministry of

Agriculture of Ethiopia N: P2O5:S, fertilizer will substitute Diammonium Phosphate in near future. However, its application rate for onion production in Dembyia district is not yet known. Therefore, the aim of this study is to assess the constraints and production practices of onion and to evaluate the responses of onion to the newly introduced fertilizer

N:P2O5:S, in the study area in order to contribute to horticultural development endeavors of the country in general and the Amhara Region in particular.

1.2. Objectives of the Study

General Objective

The general objective of the study was to assess onion production practices and to

evaluate the effects of different rates of N:P2O5:S fertilizer on yield and yield components of onion.

Specific Objectives

 To document the existing onion production practices, constraints and opportunities of onion production in the study area,

 To evaluate the effects of different N:P2O5:S rates on yield and yield components of onion.

 To determine the economical optimum rate of N:P2O5:S fertilizer for onion production in the study area.

CHAPTER 2: LITERATURE REVIEW

2.1. Botany and Origin

Onion (Allium cepa L.) belongs to the family Alliaceae and the genus Allium (Hanelt, 1990). The genus contains of about 750 species, among which onion, Japanese bunching onion, leeks and garlic are the most important once (Robinowitch and Currah, 2002). Onion is herbaceous biennial monocot but cultivated as an annual crop for bulb production. For seed production onion is cultivated as biennial crop, in the first season bulbs are formed while flower stalks and seeds are developed in the second season (Lemma Dessalegn, 1998).

The onion bulb consists of the thickened bases of leaves attached to a small conical stem. The bulb varies from flat to round in shape. Leaves are long, round and hollow. Flowers are small in size and formed at terminal tip of the stems as umbels (Norman, 1992).

The primary center of origin of onion is Central Asia with secondary center in Middle East and Mediterranean Region (Zohary and Hopf, 2000, Grubben and Denton, 2004).

2.2. Distribution and Importance of Onion

Onions are one of the most ancient vegetable crops under cultivation. Onion has been widely distributed to various countries of the world. Currently onions are grown in at least 170 countries of the world (FAOSTAT, 2014). In 2014 production year, 859, 44419 million t/ha of onions were produced across the world. China and India are the leading onion producing countries with 1,025,000 and 1,203,565 million hectare of harvested area, respectively (FAOSTAT, 2014). According to FAOSTAT (2014), China contributed 26.3% of the total world onion production followed by India with 22.6%. In terms of productivity however, USA is the first country in the world with 54.6 t ha-1 followed by Netherland (49.7 t ha-1), Egypt (33.7 t ha-1) and Iran (31.8 t ha-1) (FAOSTAT, 2014).

Onion is probably cultivated in almost all countries of the tropical Africa including Ethiopia (Grubben and Denton, 2004). In Ethiopia, onion is relatively a recent introduction. It was introduced to the agricultural community in the early 1970s through foreigners (Currah, 1990). However, it rapidly becomes a popular vegetable crop widely grown in the country (ETFRUIT, 1992).

According to Lemma Dessalegn and Shimeles Aklilu, (2003), onion is produced in many parts of the country by smallholder farmers, private commercial growers and state enterprises mainly in Awash Valley, Lake Region and Amhara region around Lake Tana areas where the bulk of dry bulbs and seed are produced (Sisay Habtie, 2004, BoFED, 2003).

According to recent statistical data from CSA (2014) the production and productivity of onion in Ethiopia is estimated to be about 230,745.2 tons and 10.1t/ha, respectively. In the same production season about 705,877 households were participated in the production of onion. Onion is one the most important cash crops produced by small scale farmers that helps the farmers to increase their income and thus to improve their livelihood (Lemma Dessalegn and Shimelis Aklilu, 2003). Its production is likely increasing in the near future because of the expansion of irrigable areas in the country (MoARD, 2005).

Onion is by far the most important of all bulb crops cultivated commercially in most parts of the world (Simon, 1992). It is primarily used as flavoring agent in preparing various dishes. Its distinctive pungency is due to the presence of a volatile oil (allyl propyl disulphide) (Malik, 1994). The matured bulb contains some starch, appreciable quantities of sugars, some protein, and vitamins A, B, and C and minerals (Malik, 2000). Moreover, onion has medicinal importance because of its anticarcenogenic, and antibiotic properties and anti platelet, antithrombotic activities (Griffiths et al., 2002).

2.3. Soil and climatic requirement of Onion

Onion is adapted to a wide range of temperatures and relatively frost tolerant. Best production is obtained when cool temperatures prevail over an extended period of time that permit considerable foliage and root development before bulbing starts. Bulb formation is favored by relatively high temperatures (Raemaekers, 2001). An optimum temperature for the production of onion ranges from 18 to 27°C. Temperatures below the optimum ranges caused bolting of plants consequently reduced bulb yield. Similarly temperatures above 30°C lead to early maturity of the plant and reduced bulb yield (Lemma Dessalegn, 1998).

Seed production is also an important practice in onion production. Onion has specific temperature requirements for seed and bulb production. In Ethiopia, day temperatures

ranging from 20 0C – 26 0C and night temperatures of 11 – 15 0C are ideal for bulb production, whereas temperatures between 90C and 17 0C are favorable for onion seed production since these temperatures induce flower stalk development in onion (Lemma Dessalegn, 1998). Onion grows well in altitude between 700 to18000 meters above sea level (Lemma Dessalegn, 2004).

Onion can be grown in all types of soils. But for higher yield well drained friable sandy loam soils with high fertility and plenty of organic matter are preferred (Brewster, 1994). Onion is also sensitive to highly acid soils and grows best when the pH is between 6.2 and 6.8 (Raemaekers, 2001).

2.4. Farmer`s Onion Production Practices in Ethiopia

Onions are one of the most important ingredients in the Ethiopian kitchen (MoARD, 2005). It is grown in high land and mid-altitudes of the country mostly by smallholder farmers. The major onion production regions in Ethiopia are Amhara, Tigray, Oromia, Benishngule-Gumuz, Gambela and (SNNP) South Nation Nationalities and Peoples Regions (CSA, 2013). Commercial production of onion is concentrated in central rift valley regions and Amhara Regions around Lake Tana areas and in some extent in Tigary region (Lemma Dessalegn and Shimelis Aklilu, 2003, Sisay Habtie, 2004 and BoFED, 2011). It is an important cash crop of Ethiopian farmers that helps them to improve their income. The crop is produced for local as well as regional export market like Djibouti, Somalia, and Sudan (MoARD, 2005). Both bulb and cut flowers 13,957 tons was exported to export market and a value of 2.98 million USD was earned in 2011 (FAOSTAT, 2014).

Onion seedlings are produced mostly on raised seedbed in nursery. After two months when seedlings attain 13–15 cm height or at 4–5 leaf stage, they will be transplanted in the production field. They are planted with ridge planting system with the spacing of 40, 20 and 10 cm between ridges, rows and plants, respectively (Lemma Dessalegn , 2004). Most framers don’t apply inorganic as well as organic fertilizers (Lemma Dessalegn and Shimelis Aklilu, 2003). Even those farmers who apply fertilizer, they don’t use the recommended rates. According to EIAR (2007) the blanket recommendation of fertilizers for the production of onion in Ethiopia are 150 kg ha-1 of urea and 200 kg ha-1 of DAP.

Since onion is mostly produced during the dry season, it requires irrigation water (Lemma Dessalegn and Shimelis Aklilu, 2003). Farmers irrigate their land every 15 days depending on the availability of irrigation water without considering the developmental stages. This may lead to water stress or overwatering and consequently to reduced yield (MoARD, 2005).

However, the recommended irrigation frequency for onion is two times a week for the first three weeks after transplanting and at 5-7 days interval then after depending on the type of soils and weather conditions (MoARD, 2005). Furrow, and flood irrigation are the methods mostly employed by farmers to supply irrigation water in the production field (Lemma Dessalegn and Shimelis Aklilu, 2003). The sources of water for irrigation are rivers, lakes, natural spring and stream water (ANRS BoFED, 2011). Significant numbers of onion growers have water pump to pull out water from water sources and others divert the water sources using channels.

Due to favorable tropical conditions in Ethiopia which favor the development of pests, onion is suffering from various diseases and insect pests throughout the country including the study area. Improper agronomic practices employed by smallholder farmers for the production of onion also contributed to high incidence and severity of pests. The losses caused by pests are further aggravated due to the fact that most onion growing farmers does not use the exact pesticides and the recommended rates for the control of pests. The most common diseases occurred in Ethiopia onion farming system are purple blotch, onion neck rot and powdery mildew caused by the fungi Alternaria porri, Botrytis cineraria and Peronospora destructor, respectively (Lemma Dessalegn and Shimelis Aklilu, 2003). Among insect pests, thrips, mites and cut worms are the most important once in farmer`s onion farms (Lemma Dessalegn, 2004). .

All farmers harvest their onions manually by pulling up the tops of onion plants after 70- 80% of the plant populations are bent just above the ground level. Most of the farmers don’t practice curing/drying after harvesting which reduces the shelf life of harvested onions and thus increases the postharvest losses. Farmers are not storing onion for long period of time. They rather sale their produces immediately with current market prices which is mostly low during the main growing season (Melkamu Alemayehu et al., 2015). Generally the production and productivity of onion under the framers management practices is low compared to the potential. This is presumably due to improper agronomic

practices employed in the production practices, shortages of improved onion varieties, diseases and insect pests and poor extension services (MoARD, 2005).

2.5. Potentials and Constraints of Onion Production in Ethiopia

Due to altitudinal differences existing in the country, Ethiopia including Amhara Region has diverse agro-ecologies that enable the country to produce both tropical, subtropical and temperate vegetables including onion throughout the year (Kubsa et al., 2006). The country including Amhara Region is endowed with underground and surface water potential which can be used for the production of horticultural crops including onion (Selesh Bekele and Awulachew, 2010). Moreover, the existence of vast area of cultivable land and fertile soils make the country suitable for commercial production of onion ((Joonsten, et al., 2011). The production of horticultural crops in general and onion in particular is labor-intensive enterprise (EIA, 2012). In this respect, more than 50% of the population of Amhara Region is at working age (BoFED, 2003) that can be actively engaged in the production of onion.

The increasing demand in export market can be also considered as an important opportunity for farmers in Ethiopia including those in Amhara Region to produce onion having export quality, since the country is near to the world market compared to other exporters (Joonsten, et al., 2011).

Moreover the Ethiopian government is committed to enhance the horticulture sector by developing irrigation schemes that enable the farmers to produce vegetables including onion throughout the year as indicated in its first Growth and Transformation Plan 2010- 2015 (MoFED, 2010). In this regard the government of Ethiopia and Amhara Region are developing large, medium and small scale irrigation schemes to enhance the production of fruits, vegetables and other cash crops so that to improve the livelihood of the smallholder farmers (Joonsten, et al., 2011). In addition the Governments are also dedicated to promote private investments in horticulture sector by implementing investment initiatives like duty free, income tax exemption, loss carry forward, remittance of fund and investment guarantee and protection (EIA, 2012).

Despite high potentials, the production and productivity of horticultural crops including onion in Ethiopia in general and in Amhara Region in particular is very low. They are mostly produced by smallholder farmers where inappropriate agronomic practices are employed, agricultural inputs such as fertilizers, improved varieties and pesticides are not sufficiently used, and inappropriate postharvest handling practices are employed. Generally farmers produce horticultural crops with traditional farming system that leads to low production and productivity (Melkamu Alemayehu et al., 2015).

Moreover, the production of horticultural crops is dependent on natural rainfall and consequently their production will be seriously reduced by rainfall fluctuation, Similar to other horticultural crops, onion is produced by traditional farming practices, the farmers lack improved onion production technologies. Improved onion seeds are scarce because of undeveloped onion seed production system in the region. Fertilizers are available mostly for main season crops. For irrigated vegetable crops like onion fertilizers are not available in sufficient quantity (Melkamu Alemayehu et al., 2015).

Diseases and insect pests are the other major constraints of onion production in Ethiopia including Amhara Region. Pesticides are not used by some farmers and also not available sufficiently. Some traders mix pesticides with other substances (adulteration) which may either reduces their effectiveness or harm the crop plants and consequently incur economical losses for onion growing farmers (Edossa Etissa, 2013).

Poor infrastructures such as rural roads and means of communication for efficient flow of goods and market information are limited; most of the production sites are not accessible for vehicles, handling and means of transportation are rudimentary, onions are perishable by nature it cannot be stored for long period of time without quality deterioration unless properly handled and there is a serious problem in the marketing of horticultural crops including onion in the region, such conditions affect not only the income negatively but also the interests of farmers to participate in onion production in the following years (Melkamu Alemayehu et al., 2015).

2.6. Response of Onion to Inorganic and Organic Fertilizers

Nitrogen (N) and phosphorus (P) are referred as the primary macronutrients because of the probability being deficient in plants and their large quantities taken up from the soil

relative to other essential nutrients (Marschner, 1995). The major essential plant nutrients particularly nitrogen (N) and phosphorous (P) are mostly deficient in many soils of tropical Africa (Richardson, 1968) which might also be true for many Ethiopian soils (Murphy, 1959).

Nitrogen is an important component of proteins, enzymes, and vitamins in plants. It is a central part of the essential photosynthetic molecule and chlorophyll (Marschner, 1995). Therefore, nitrogen is required by plants in much greater quantities than most of the nutrients and essential to increase onion yield both in quantity and quality (Kafkafi and Genbaum, 1971). The authors also noted that available nitrogen is often a more limiting factor for the plant growth than any other nutrients. .

As shallow rooted crop, onion is a heavy feeder of nutrients and require ample amount of nitrogen for optimum yield. Too much nitrogen however can result an excessive vegetative growth and thus delay maturity. Moreover excessive vegetative growth increases susceptibility of onion plants to diseases and reduces dry matter contents and storability of onion bulbs. Consequently excess nitrogen results reduced onion yield both in quantity and quality (Brewster, 1994; Sørensen and Grevsen, 2001). On the other hand, under sub-optimal supply of nitrogen, onion plants can be severely stunted resulting undersized bulbs and thus reduced yield. Hence, sub-optimal levels of this nutrient in the soil adversely affect the quantity, quality, and storability of onion bulbs. Onion bulb size is related to planting density and smaller bulbs are formed at closer spacing. In such conditions application of increased amount of nitrogen fertilizers is especially important to produce optimum-sized onion bulbs (Rice et al., 1993).

Phosphorus is claimed to be the second most important plant growth limiting nutrient (Tisdale et. al., 1995). It makes about 0.2-0.5% of the plant’s dry weight (Bieleski, 1973). Phosphorus is known to be involved in several physiological and biochemical processes of plants; being components of membranes, chloroplasts and mitochondria and constituent of sugar. Phosphorus also played a crucial role in energy transfer reactions and metabolic processes in plant maturity, fruit setting, and seed production (Brady and Weil, 2002; Miller and Donhaue, 1995; Theodorou and Plaxton, 1993).

Phosphorus deficiency is one of the largest constraints to crop production in many tropical soils. The reasons for that is either low content of phosphorus in the soil or high

phosphorous fixation (Fairhurst et al., 1999). Therefore, most of the soils throughout the world are phosphorus deficient (Batjes 1997; Zaidi and Mohammad, 2005).

Application of phosphorous fertilizers is therefore associated in most cases with increase in growth and development of crop plants including onion. As reported by Greenwood et al. (2001) for example, application of phosphorous fertilizer in soils with moderate phosphorous content enhanced the growth and yield of onion. Similarly, Singh et al. -1 (1998) reported an increase of P2O5 from 25 to 100 kg ha decreased weight loss, sprouting and rotting of onions which were stored for 160 days. It is not enough in soils that are relatively low in phosphorous, onion growth and yield can be enhanced by applied phosphorous (Alt et al., 1999).

The presence of phosphorus in the soil encourages plant growth because phosphorus is a major building block of DNA molecules (Pant and Reddy, 2003). In addition, Hinsinger, (2001) reported that the two forms of phosphorus in soil are organic and inorganic. Therefore, inorganic phosphorus is readily absorbed and used by plant if it is not fixed.

Phosphorus has been recommended at rates of 33 to 80 kg·ha−1 (Sharma et al., 2003). For instance, results of long term Phosphorus fertilizer trials on loamy sand soils in Germany have shown a strong response of onion to Phosphorus fertilization in the range of 0 to 52 kg ha-1 (Alt et al., 1999).

The effects of phosphorus in plant growth are investigated by many workers (Nikolay et al., 1996; Warade et al., 1996; Hinsinger, 2001; Pant and Reddy, 2003 and Shafeek et al., 2004). All of them agreed that, the presence of phosphorus in the soil encourages plant growth, because phosphorus is an essential nutrient.

Phosphorus fertilizer had a major effect on yield of onion plant, hence increased total bulb yield and its components. It may be attributed to the enhancement of phosphorus on the plant growth and it’s reflected on the bulbs yield. Many investigators had obtained a similar trend of results (Gupta and Sharma et al., 2000, Shafeek et al., 2004).

In addition, optimum growth and yield were obtained with phosphorous application of 22 kg·ha−1, but even higher levels gave a response with variety Pusa White Flat, which responded with optimum growth and yield at 33 kg·ha−1 (Jha et al., 2000).

Sulfur is also an essential plant nutrient required for growth and development. As macronutrient, sulfur has a positive effect on quality of onion (El-Shafie and El- Gamaily, 2002; Bloem et al., 2004). It is important in the expression of the flavor intensity of bulbs which is associated with pungency (propyl disulfides and other disulfides) and sugars (glucose, fructose, sucrose) contents of onion. Onion is a sulfur loving plant and is required much for proper growth and increased yield of onion (Bloem et al., 2004). The volatile sulfur compounds in onion are released when onion bulbs are cut or bruised through the action of the enzyme allinase. The amount and kinds of sulfur compounds present in the bulb differ with onion varieties. Moreover sulfur is essential for building up sulfur containing amino acids (Anwar et al., 2001).

In recent years, sulfur is receiving more attention throughout the world in the production of crops. Application of sulfur to the soil has several effects such as reducing pH, improving soil-water relation and increasing availability of nutrients like P, Fe, Mn and Zn (Marschner, 1998). Mengel and Kirkby (1982) reported that sulfur is absorbed by plants mainly in form of sulfate, which has minimum competition for absorption with other elements. Sulfur requirements of onion vary with soil texture, leaching losses, sulfur content of irrigation water, previously used fertilizer and amendments containing sulfur (Ahmed, et al., 1988). They reported that the diameter and weight of onion bulbs were significantly improved with the application of sulfur up to 24 kg ha-1. They further reported non-application of sulfur in deficient soils resulted low yield of onion. Since sulfur is essential for chlorophyll formation, its deficiency leads to restricted shoot growth, stiffed stem and woody and small sized bulbs. However excess sulfur can also increase onion pungency which may be undesirable for fresh market (Bloem et al., 2004).

Application of organic matters also increases growth and development of crops including onion by improving physical, biological and chemical properties of soils (Dauda et al., 2008).Addo-Quaye et al. (1993) defined organic matter as a mixture of residues and remains of higher plant and animal life, soil organisms such as earthworms, ants, bacteria, fungi, actinomycetes, protozoa, nematodes and algae in various stages of decomposition. Decomposition or decay of these materials leads to the formation of humus which improves the organic matter contents of the soils (Dunn, 1994, Addo-Quaye et al., 1993) and thus enhances the growth and development of crops including onion.

In the research results from Snyman et al., (1998), organic materials, like sheep and chicken manure have been improved physical properties such as soil structure and aggregate formation. Adams et al. (1997) reported that the presence of partially decomposed organic matter created an open soil structure and increased water holding capacity of the soil.

In addition organic matter improves the availability of phosphorus in highly weathered acidic soils through blocking fixation sites with organic complexes. Similarly Adams et al., (1997) reported the application of organic matter increased CEC and reduced the soil pH that improved the availability of plant nutrients. Organic matter may also improve the fertility of soils by adding plant nutrients or making nutrients in soil available to plants (Sekhon and Meelu, 1994). In this regard, Tisdale et al. (1990) mentioned that, organic matter is one of the main sources of boron in acid soils.

Generally the application of organic matter enhances the growth, development and yields of onion by improving the properties of soils necessary in onion production (Arisha et al., 2003).These properties lead to the improvement of root penetration, soil erosion resistance and increase availability of soil moisture to plants and permeability of water and improve soil aeration. Conversely, a decline in soil organic matter leads to degradation of these properties such as pan formation and reduced water holding capacity of soils. In this regard, Akoun (2004) confirmed that organic manure increased the nutrient status of the soil which leads to increased onion yield. According to Shaheen et al., (2007) organic fertilizers affected onion root growth positively by improving the root rhizosphere including the population and activities of microorganisms. Therefore, organic manures can be used as alternative to mineral fertilizers particularly in resource poor farmers of developing countries (Brady, 1984).

The integrated application of organic and inorganic fertilizers is the best approach for soil fertility management in the production of onion. Because, the approach improves the physical, chemical and biological properties of the soil as well as it replace plant nutrients which are removed by the previous crops. In the research from Rumpel (1998) where the effect of different rates of animal manure and NPK fertilizer were tested, addition of animal manure increased the onion yield compared to NPK fertilizer alone. Similarly application of manure in combination with NPK fertilizers increased the onion yield and nutrient uptake of onion (Sharma et al., 2003).

CHAPTER 3: MATERIAL AND METHODS

3.1 Description of the Study Area

Dembyia district is found in North Gondar Administration Zone of Amhara Region. Dembiya is located 370, 20'224" N longitude and 120, 25', 609" E latitude. The district has a total area of about 1, 261.96 square kilometer and comprises of 40 rural Keble’s and 5 urban towns. The total population of the district is about 271,053. Of which 42,746 households are engaging in agriculture (CSA, 2007). The capital city, Kolla Diba, is located at about 775 km North West of Addis Ababa and 34 km Southwest of Gondar. The district is known for its topography. About 85%, 8%, 4.8%, and 2.2% and of the district is cultivated, mountain, valley and water body respectively (DWRDAPO, 2014). Out of the cultivated land, about 25% is irrigable land. The mean annual rainfall of the area is about 1200 mm which falls mostly in the months between May and September. The annual mean minimum and maximum temperatures of the area are 170C and 28 0C, respectively (Kahasy Berhe et al. 2013) unpublished. The altitude of the district ranges from 1858 to 2200 meter above sea level which is suitable for the production of a wide range of crops. Most of the agricultural land is allocated for annual crop production where teff, maize, finger millet and sorghum are the major crops produced in the area (DWRDAPO, 2014).

The experimental part of this study was conducted in Jenda Keble of Dembyia District during the 2014/15 under irrigation. The experiment site was located 370, 13'996" N latitude and 120, 23', 860" E longitude and at altitude of 1858 meter above sea level.

Figure 3.1. Map of the study area Source: Ethio- Nile Irrigation and Drainage Project, GIS team 3.2 Assessment of Production Practices of Onion

3.2.1. Sampling procedure

The farmer`s onion production practices was assessed in three major onion producing kebeles such as Sufankara, Guramba Michel and Debir Zuriya which were selected purposively from forty kebeles in the district based on onion production potentials (Gomez, K.A, 1984). According to the agricultural office a total of 300 households were engaged in the production of onion in above mentioned kebeles. The number of sample households was determined by using the common method (10% of the total population) as described by L. R. Gay (1987). According to him, the sample size is as "rule of thumb" 10% of the total population, if the population is at the range of 101 to 1000. Thus, from the total 300 onion producers, a total of 30 households (HH), ten HH from each kebele were used in the study. The individual sample households were then selected by lottery method from the document prepared by the Agriculture Office of District.

3.2.2. Data collection and analysis

Primary data about demography and socio-economic of the study area as well as the onion production constraints and practices of farmers were collected through interview and focus

group discussions using semi-structured questions. Household heads were face to face interviewed by trained enumerators under the close supervision of the researcher. In case the head of households were not found at home, the interviewers were revisiting the households two times at different time intervals. If the interviewers failed to get the households or if the head of the household were unable to give information then the household was replaced by one of the family members whose age was greater than 18 years.

All sets of data were subjected to SPSS software and descriptive statistics such as mean, standard deviation, frequency, etc. were used to interpret the result.

3.2.3. Irrigation water measurement and procedure

The amount of the irrigation water used by the selected thirty farmers was assessed by float method (Bessembinder et al., 2005). The measurement was carried out on 20 meter straight water canal to find the velocity (m/s) of water tennis ball was used and time (s) required for traveling the 20 meter canal was measured. The measurement was carried out three times and the mean velocity was then calculated and multiplied with correction factor (0.85) to estimate the average water velocity in the irrigation canal.

To measure the amount of water flow (m3), the width and depth of the water surface in the canal was measured. The width was measured ten times within the twenty meter canal and the average width was taken for calculation. The depth of irrigation canals was measured at left and right edges and at the center of the canal which was repeated four times within the canal distance and the mean depth of the canal was taken to calculate the amount of water flowed. This was combined with the number of application and duration of application for each irrigation event to estimate the total applied water. Finally the water flow (m3), total irrigation water used and its productivity were calculated using the formulas below (Bessembinder et al., 2005).

Water flow (m3/s) = water velocity (m/s) x width (m) x depth (m)……………………. .(1)

Total irrigation water used (m3) = time (s) required to irrigate the land x water flow (m3/s) x number of irrigation …………………………………..………………………… (2)

Crop water productivity (kg/m3) = yield (kg)/total water used yield (m3) ………. (3)

3.3. Effects of Different Rates of N: P2O5:S Fertilizer on Yield and Yield Components of Onion

3.3.1. Treatments and experimental design

The experiment was consisted of twelve fertilizer rates: nine N: P2O5:S fertilizer rates, one farmer`s practice, one blanket recommendation and one without fertilizer as control (Table

3.1). As a base for N: P2O5:S fertilizer, the blanket recommendation of urea and DAP for onion production as indicated EIAR (2007) was taken. After calculating the nutrients in the blanket recommendation, 30% of nutrients were added and subtracted using N: P2O5:S fertilizer to determine the N: P2O5:S fertilizer rates. The rate of fertilizer in farmer`s practice was determined by interviewing 10 onion producing farmers in the study area and then the mean fertilizer rate was taken as one treatment in this study. The treatments were arranged in randomized complete block design (RCBD) with three replications. Each plot was 3 meter wide and 1.8 meter long. The space in between plots and replication was 50 cm and 1m, respectively.

Table 3.1. Experimental treatments used in the study area

Nutrient ((kg ha-1) concentration used Treatment Numbers N:P2O5:S 1 0:0:0 2* 24.96:28.52:0 3** 105:92:0 4 73.5:64.4: 11.86 5 73.5:92:16.95 6 73.5:119.6:22 7 105:64.4:11.86 8 105: 92:16.95 9 105:119.6:22 10 136.5:64.4:11.86 11 136.5:92:16.95 12 136.5:119.6:22

* Rate of fertilizer in farmer`s practice ** Rate of fertilizer at blanket recommendation EIAR (2007)

Figure 3.2. Lay out of field experiment

3.3.2. Management of the experimental plots

Onion variety “Adama Red” was used in this experiment which is dominantly produced in Dembyia District. First onion seedlings were raised in nursery. For that purpose the nursery soil was plowed 2-3 times. Seeds were sown on well prepared nursery bed and all the recommended seedling management activities were preformed according to Lemma Dessalegn and Shimeles Aklilu (2003). When seedlings attained the 3 to 4 leaf stage or when they attain the height of 12 to 15 cm, healthy and uniform seedlings were transplanted in to well prepare experimental field. Planting of onion seedlings was done using ridge planting system where the spacing between water furrows, rows and plants were 40cm, 20cm and 10cm, respectively, as recommended by Lemma and Shimeles Aklilu, (2003). The distance of 50 cm and one m was maintained between plots and replication, respectively, to facilitate cultural practices. Each experimental plot was 5.4 m2 in size and accommodated five double rows with 16 plants in each row and 160 plants per plot.

While N: P2O5:S was used as source of sulfur DAP and N: P2O5:S were used as a source of nitrogen and phosphorous. The respective amounts of DAP and N:P2O5:S were applied to the experimental plants as basal application during transplant. The amount of urea was first divided into two equal quantities. The first half was applied during transplanting and the remaining half was then applied as side dressing 45 days after transplanting as described by Nandpuri et al. (1968).

The experimental plots were kept moist throughout the growing season. For the first two weeks after transplanting, plants were irrigated at four days interval (Lemma Dessalegn and Shimeles Aklilu, 2003). Then after, experimental plots were irrigated at six days interval using furrow irrigation system. The experimental plots were kept free from weeds. A total of six hand weeding and cultivation activities were conducted uniformly for each experimental plot during the crop growing period to remove weeds and to lose the soil. Insect pests like thrips cutworms were observed in the experimental plots. However, they were successfully controlled by spaying pesticides Profit 72% EC with the concentration of 0.75 l/ha at fifteen days interval (Edossa Etissa, 2013).

3.3.3. Data collection

Soil sampling

To know the fertility status of the experimental soil, samples were taken randomly from the experimental field at five spots diagonally at the depth of 20 cm before planting and mixed to make a soil composite. Physical and chemical properties of the composite soil were analyzed at Gondar soil research laboratory.

In the experimental part of the study both the growth and yield parameters of onion were collected from the central three double rows with net plot area of 3.52 M2 to avoid boarder effects.

Growth parameters

Plant height (cm): Plant heights of ten randomly selected plants were measured from the soil surface to the top of the longest leaf using a ruler at physiological maturity and the mean values were computed for further analysis.

Leaf length (cm): The longest leaves of ten randomly selected plants at physiological maturity was measured from the point of their emergence using ruler and expressed as a mean value in centimeter (cm) and used for further analysis.

Leaf number: Number of leaves of ten randomly selected plants per plot was counted at physiological maturity and the mean values were computed.

Leaf diameter (cm): The mid-diameter of the longest leaves of ten randomly selected plants was measured at physiological maturity using caliper and the average mean diameter was used for further analysis.

Above ground Biomass (g/plant): the above ground biomass of ten randomly selected plants were cut off and weighed at harvest and average weight was computed and used for further analysis.

Dry weight of above ground Biomass (g/plant): Dry weight of ten randomly selected plants at harvest was measured using sensitive balance after drying them in oven for 24 hours at 65OC and the mean values per plant was computed and used for further analysis (Guesh Tekle, 2015).

80% days of maturity: the number of days elapsed from the time of planting up to the time when 80% of plants in the plot became yellow, dry and collapsed at the neck was counted and the mean values were computed and used for further analysis (Guesh Tekle, 2015).

Yield parameter

Bulb weight (g): The mean bulb weight of ten randomly selected bulbs at harvest was computed and used for further analysis (Guesh Tekle, 2015).

Bulb length (cm): The lengths of ten randomly selected bulbs per plot were measured from the bottom to the top using caliper and the mean value was computed for further analysis (Guesh Tekle, 2015).

Bulb diameter (cm): The mean size of the bulb at harvest was computed by measuring the diameters at the middle of ten randomly selected bulbs in each plot using caliper (Lemma and Shimeles, 2003).

Marketable bulb yield (t/ha): Bulbs which were free of mechanical, disease and insect pest damages, uniform in color and medium to large in size (20 - 160 g) were considered as marketable. The weight of such bulbs obtained from the net plot area of each plot was measured in kilogram using scaled balance and expressed as ton per hectare (Lemma and Shimeles, 2003).

Unmarketable bulb yield (t/ha): Harvested bulbs which were under as well as over sized (<20g and >160g), misshaped, decayed, discolored, diseased and physiologically disordered were considered as unmarketable according to Lemma and Shimeles (2003). The weight of such bulbs obtained from the net plot area of each plot was measured in kilogram using scaled balance and expressed as ton per hectare.

Total bulb yield (t/ha): Total yield of onion was obtained by adding marketable and unmarketable bulb yields and expressed as ton per ha (Guesh Tekle, 2015).

3.3.4. Data Analysis

The collected data were subjected to analysis of variance (ANOVA) using SAS (Statistical Analysis System) version 9.1. Mean separation was carried out using Least Significant Difference (LSD) at 1% or 5% level of significance (Gomez, K.A, 1984).

Economic Analysis (partial budget analysis) The Marginal rate of return was analyzed using the technique described by CIMMYT

(1988) to assess the current costs and economical optimum rates of N:P2O5:S fertilizer.

CHAPTER 4: RESULTS AND DISCUSSIONS

4.1 Assessment of Onion Production Practices

4.1.1 Demographic characteristics the respondents

Sex, age, marital status and family size of respondent

The demographic characteristics the study sample farm households are presented on (Table 4.1.) Accordingly about 83.3% % of the interviewed households were male-headed and the remaining 16.7% of the households were female headed. This is similar to the finding of Mulugeta Enki (2000) who reported that gender differentials among the farm households positively influenced the adoption of production a male headed household increases than a female headed household.

The age distribution of the study population showed that the majority of onion producers (60%) were between the ages of 33-48 and about 36.7% of onion producers were greater than 48 years old and the remaining 3.3% onion producers were between 19–33 years old. The majorities (60%) of onion producers in the study area were matured and at working ages (Taha Mume, 2007).

The results of marital status showed that the majority of the respondents were married which accounted 80% and 13.3% of respondents were single. The remaining 6.7% of onion producers were divorced (Table 4.1).

Regarding to family size, about 83.3% of the respondents have a family size of greater than four persons. About 16.7% of the interviewed onion producers had less than four family members. This can be associated with high labor requirement of onion production (Table 4.1).

Table 4.1 Sex, age, marital status and family size of respondent in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Sex of HH heads Female 30 10 10 16.7 Male 70 90 90 83.3

Age of HH heads 19-33 10 0 0 3.3 33-48 40 70 70 60 >48 50 30 30 36.7 Marital status of HH heads Single 10 10 20 13.3 Married 80 90 70 80

Divorced 10 0 10 6.7 Family size of HH

>4 90 70 90 83.3 <4 10 30 10 16.7

Educational status

According to the survey results, about 16.67% of the interviewed HH heads were able to read and write while 20% of the respondents were illiterate and 50% of farmer’s household have attended 1-6 grade and the remaining 13.33% have attended 8-10 grade (Figure 4.1). Based on these results, implementation of improved onion production packages with some additional extension activities (training) in the study area might be easy. This is true as suggested by Taha Mume (2007), where he found that educational status is one of the main determinates for adoption of improved onion production packages.

Figure 4.1. Educational status of the respondents in the study area

Landholdings of the respondents

The size of farmland owned by farmers may affect the portion of land allocated for onion production. According to the survey results, about 80% of the respondents owned cultivated land greater than one hectare. The remaining 20% of them have a cultivation land which is equal or less than one hectare (Table 4.2). The results of this study are similar with the finding of Mulugeta Enki (2000), Yishak Gecho (2005) and Mesfin Astatkie (2005) (unpublished). Besides land availability, where they found that water, labor, capital, market and transport facilities were the most important factors for onion production packages.

About 80% of the respondents allocated from 0.25-0.75 hectares of irrigable land for onion production in the study area. While 3.3% of the respondents allocated irrigable land which was less than 0.25ha, about 16.7% of them allocated irrigable land greater than one hectare for onion production (Table 4.2).

Table 4.2. Land allocation of the respondents in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) Descriptions (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Land holding 0.5 ha 0 0 10 3.3 0.5- 1 ha 10 10 30 16.7 1-1.5 60 30 50 46.7 >1.5 ha 30 60 10 33.3 land allocated for onion production < 0.25 0 0 10 3.3 0.25 – 0.5 70 70 80 73.3

0.5 – 0.75 10 10 0 6.7

>1 20 20 10 16.7

4.1.2. Raising and transplanting of onion seedlings

Seedling management in the nursery

According to the survey results none of the respondents produce onion seed. About 86.7% onion producers were replied that the source of their onion seeds was private shops, BoA, NGOs and from adjacent districts while 13.3% of them bought the onion seed directly from ET-fruit Bahir Dar branch and other whole sellers (Table 4.3).

Different onion varieties are grown by respondents in the study area. About 60% of the interviewed HHs produced the variety `Adama Red` while 26.7% and 13.3% of them produced `Bombay Red` and Red Creole varieties, respectively. Most of the households (93.3%) produced onion in off season using irrigation water. Seedlings were raised by broadcasting method of sowing on nursery bed (Table 4.3).

Table 4.3.source of seeds, varieties used, growing season of onion in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Onion seed production Yes 0 0 0 0 No 100 100 100 100 Source of onion seeds Others 30 0 10 13.3 Private shops 70 100 90 86.7 Varieties of onion Adama Red 60 70 50 60 Bombay Red 30 20 30 26.7 Red Creoles 10 10 20 13.3 Onion growing season Rainy season 20 0 0 6.7 Irrigation 80 100 100 93.3 Seed sowing practice Line sowing 0 0 0 0 Broadcast on seed bed 100 100 100 100

Transplanting of onion seedlings

Most of the respondents (70%) in the study area transplanted onion seedlings at the age ranging from 6-7 weeks after sowing or when the seedlings attained the height of 15 cm or at four leaves stages (Table 4.4).The remaining 30% of the respondents transplanted onion seedlings at the age greater than seven weeks after sowing. Generally, the results of this study are in agreement to the information given by Lemma Dessalegn and Shimeles Aklilu (2003) they showed that onion seedlings at the age ranging from 6-8 weeks are ready for transplanting.

However, about 56.7% of the respondents planted onion seedlings at non-recommended spacing due to lack of skill and knowledge. Only 43.3% of them used the recommended spacing of 10 x 20 x 40 cm Lemma and Shimeles Aklilu, (2003)

About 70% of the respondents planted their onion seedlings early in the morning that may expose the newly transplanted seedlings to the coming strong sunlight during the day time, whereas 23.3% of the respondents were planted their onion seedlings during late evening and the remaining 6.7% of respondents were planted their onion seedlings during noon time. This time of transplanting is in agreement with the recommendations of (Lemma and Shimeles Aklilu 2003) who suggested to transplant onion seedling late in the afternoon to protect the newly transplanted seedlings from the coming strong sunlight in day time that may reduces the establishment of transplants (Table 4.4).

Table 4.4. Age, spacing and time of ttransplanting of onion seedlings in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) Descriptions (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Ages of seedlings 6-7 weeks 30 90 90 70 >7 weeks 70 10 10 30 Spacing of seedlings 10 x 10 x 30cm 60 40 40 46.7

10 x 20 x 40 cm 30 50 50 43.3

Others 10 10 10 10

Time of transplanting

Early morning 50 60 100 70

Noon time 10 10 0 6.7

Late evening 40 30 0 23.3

4.1.3. Onion production and harvesting practices in the study area

Types, rates, times, and methods of fertilizers application in the study kebeles Respondent farmers in the study area applied chemical fertilizers such as DAP and UREA to improve the soil fertility so that to increase production of onion. While 63.3% of the interviewed households used DAP, about 36.7% of them did not used DAP for onion production (Table 4.5). Among DAP users, about 50% of the household head applied DAP below its blanket recommendation (200 kg DAP/ha) which is recommended by EIAR (2007). About 66.7% of the respondents applied DAP at the time of planting which is in agreement with the recommendation of (Lemma Dessalegn, 2004). However, 33.3% of the farmers applied DAP after transplanting due to lack of knowledge.

Similarly, about 50% of the respondents don’t applied urea for onion production in the study area. Especially in Sufankara kebele about 70% of the onion growers didn’t use urea fertilizer for onion production which may have its negative effect on the productivity of onion in the kebele. Among the urea users in the study kebeles, 50% used below the recommended rate which is 150 kg/ha EIAR (2007). Most of them (63.3%) applied the whole quantity of urea at one time during transplanting or after transplanting which is not the correct time of urea application for onion. About 36.7% of the respondents applied urea by split application method where one half of urea was applied at the time of application and the remaining half urea after planting (Table 4.5).

Generally, the rate and time of application of DAP and urea fertilizers were not according to the recommendation for onion production as indicated above which may contribute to the low level of onion productivity in the study area. According to the recommendation, the whole quantity of DAP (200 kg/ha) should be applied at the time of planting or 7-10 days after transplanting. However the quantity of urea (150 kg/ha) should be divided into two and one half should be applied during transplanting and the remaining one half 45 days after transplanting or at 35-50 cm stage of the plants (Lemma Dessalegn and Shimeles Aklilu,2003).

Table 4.5. Inorganic fertilizers used and their methods and time application in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent Percent (%) Percent (%) Percent (%) (%) Amount of DAP used 5 kg/ha 10 10 0 6.7 10 kg/ha 10 0 0 3.3 25 kg/ha 10 20 30 20 50 kg/ha 20 30 10 20

100 kg/ha 10 10 20 13.3

Non user 40 30 40 36.7 Time of DAP application At time of planting 70 60 70 66.7 After planting 30 40 30 33.3 Amount of urea used 5 kg/ha 0 10 0 3.3

10 kg/ha 10 0 30 13.3

25 kg/ha 0 30 20 16.7

50 kg/ha 20 20 10 16.7

Non user 70 40 40 50

Time of Urea application

During planting 70 50 30 50

After planting 10 10 20 13.3

Both 20 40 50 36.7

In case of organic fertilizer, all interviewed households (100%) used manure as a source of organic fertilizer where about 93.3% of them used two quintal of manure per hectare (Table 4.6). The quantity used is much lower than the recommendation which is about 150 quintal per hectare (Mesfin Admassu, 2009). The entire onion producers were applied the total quantity of manure applied before planting by broadcasting. This is in line with the recommendation which may give enough time for decomposition processes that should be completed ahead of time (Kokeb W/Yohanns et al, 2013).

Table 4.6. Organic fertilizers used and their methods and time application in the study area in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) Descriptions (N=10) Percent Percent Percent (%) Percent (%) (%) (%) Application of organic fertilizer Yes 100 100 100 100 No 0 0 0 0 Application of compost Yes 0 0 0 0 No 100 100 100 100 Application of manure Yes 100 100 100 100 No 0 0 0 0 Amount of manure used 2qt 80 100 100 93.3 5 qt 10 0 0 3.3

10 kg 10 0 0 3.3

Time of application Before planting 100 100 100 100

Methods of application

Broadcasting 100 100 100 100

Irrigation methods and frequency of irrigation

The majority (66.7%) of onion producers had 5-10 years irrigation experience, about 20% and 13% of them had 5 and more than 10 years irrigation experience, respectively (Fig 4.2). The study is in line with the observations of Rahmeto Negash, (2007), who justified that irrigation experiences of the respondents in the study area create suitable conditions in the promotion of improved cultural practices in the production of onion.

Figure 4.2. Irrigation experience of the respondents in the study area

Generally interviewed onion growers in the study area produced onion in a year. Most of the respondents (70%) in the study area applied water through furrow irrigation while 30% used flooding method (Table 4.7). However, the majority (60%) of the respondents in Sufankara preferred flooding as a method of irrigation water application which is not appropriate for most of vegetables including onion as mentioned by (ANRS BoFED, 2011). The source of irrigation water was river in all selected kebeles of the study area which is in agreement with the finding of Taddesse Adigo, (2008) who indicated that rivers are the main sources of irrigation water for onion production.

The frequency of irrigation is very important in onion production which differs with the weather conditions, type of soil and the developmental stages of the crop. Onion requires generally frequent irrigation since the crop has shallow root system (MoARD, 2005). However, the majority (80%) of the onion growers in the study area irrigation water was applied in every two weeks interval throughout the growing periods without considering the soil type and the stage of the crop (Table 4.7). It is not in line with (MoARD. 2005), the recommended frequency for onion is two times a week for the first three weeks after transplanting and at 5-7 days interval then after depending on the type of soils and weather conditions.

Table 4.7. Sources, methods and frequency of irrigation in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent (%) Percent (%) Percent (%) Percent (%) How many time produce onion in a year Once 100 100 100 100 Source of irrigation water Rivers 100 100 100 100 Methods of irrigation production Furrow irrigation 40 90 80 70 Flooding 60 10 20 30 Irrigation frequency Every week 0 10 30 13.3 Every two weeks 90 80 70 80

Others 10 10 0 6.7

Methods of planting Direct sowing 0 0 0 0 Transplanting 100 100 100 100

Major pests and their management occurred in the study area

According to the information of the respondents most of (80%) of the respondents were not practiced crop rotation where as the remaining 20% of them were practiced crop rotation, crop rotation is one of the best strategies to control specific diseases (Eckert, 1988). Onion is affected by various diseases in the study area; the most important diseases of onion were black leg, purple blotch and powdery mildew (Fikre Mulugeta and Olani N., 2010). About 90% of the growers used pesticides like Endosulfine 35% and Profit 72% EC during seedling stages and after transplantation to manage cut worm and thrips of onion in the study area (Table 4.8).

Similarly common insect pests of onion which are found elsewhere in the country such as cut worms, thrips and bulb aphids attack onion in the study area, which were mostly (90%) controlled by insecticide application, the remaining 6.7% were also controlled by flooding of water and 3.3% of them were by cultural practice (Table 4.8).

Table 4.8. Major pests and their management in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Crop protection Yes 0 40 20 20 No 100 60 80 80 Types of diseases

Black leg 10 60 40 36.7 Powdery mildew 50 0 20 23.3 Purple blotch 40 40 40 40 Disease control measures Using non infected 10 0 0 3.3 seeds Using chemicals 90 100 80 90 Using cultural 0 0 20 6.7 practice Types of insects

Cut worm 50 40 70 53.3

Thrips 40 60 20 40

Others 10 0 10 6.7

Insect control measures Using cultural 0 10 0 3.3 practices Using chemicals 100 90 80 90

Flooding of water 0 0 20 6.7

4.1.4 Harvesting, postharvest handling and marketing practices in the study area

According to the interviewed household heads (93.3%) in study area, onion was harvested in 4-5 months after transplanting which is in line with (Lemma Dessalegn , 2004) who indicated that onion bulbs start to mature in 4-5 months after transplanting (Fig 4.3.).

Figure 4.3. Length of maturity of onion in the study area.

The maturity indices of onion were well known by farmers in the study area. About 80% of the households harvested their onion when the leaves change their color to yellow and start to dry, the remaining 13.3% and 6.7% the households were harvested their onion by looking bulb size and by counting number of days respectively (Table 4.9). The results are in agreement with Lemma Dessalegn and Shimeles Aklilu (2003) who find that the onion plants are ready for harvesting when about 80% of the leaves turn to yellow and the tops begin to dry out and collapse.

Table 4.9. Onion maturity indices and harvesting methods used in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) Descriptions (N=10) Percent Percent (%) Percent (%) Percent (%) (%) Maturity indices

Number of days 0 10 10 6.7 Colors of leaves 100 60 80 80

Bulb size 0 30 10 13.3

Methods of harvesting By fork 90 90 80 86.7 Uprooting 10 10 10 10 Others 0 0 10 3.3

Most (96.7%) of the respondents were practice curing to improve the storability of onion bulbs. The remaining 3.3% of them were not practice curing operation (Table 4.10). Most (63.3%) of onion producers were used 3-4 weeks before harvesting as curing operation were started,. the remaining 26.7% and 10% were 1-2 weeks and >4 weeks before harvesting as curing operation were started respectively, such curing operations increase the storage life of onion as indicated by (Fikre Mulugeta and Olani N., 2010).

According to the survey results, about 50% of the sample onion producers sold their crop for retailers whereas 10% of them sold the product directly for wholesalers. The remaining 40% of interviewed onion producers sold their produces directly for the consumers (Table 4.10). The result similar with the study area is known by different customers for onion production as indicated by Simegnew Tamir (2012).

Table 4.10. Postharvest handling and marketing of onion in the study area

Sufankara Guramba Debir Zuriya Total Descriptions (N=10) Michael (N=10) (N= 30) (N=10) Percent (%) Percent (%) Percent (%) Percent (%) Curing of onion Yes 100 100 90 96.7 No 0 0 10 3.3

Length of days for curing 1-2 weeks 40 10 30 26.7 3-4 weeks 50 80 60 63.3 >4 weeks 10 10 10 10 Types curing

Left in the field 0 30 0 10

Press the top part 100 70 100 90

Purpose of onion production Sell 100 100 100 100

Home consumption & 0 0 0 0 sell Marketing of onion to

Consumers 20 10 0 40

Whole seller 50 40 30 10

Retailers 30 50 70 50

Storage conditions are very important to reduce postharvest losses in vegetables including onion. Storages should be clean, dry and cool to reduces the postharvest physiological processes and thus to increase the storage life of onions. Generally, most (73.3%) of the sample farmers in the study area didn’t store their onion. The remaining 26.7% of them stored their products for better price. Among those farmers, about 93.3% stored their product for about 3-4 weeks and the remaining 6.7% of producers were stored their

product for >4 weeks. According to the survey result, about 70% of the respondents stored the bulbs by spreading loosely on the floor of their house, while about 20% of them used bags as storage container and the remaining 10% of the respondents were put under the roof (Table 4.11). The storage practice employed by the sample farmers is generally not appropriate for onion. Onion can be stored for a long period of time when cured properly and stored in well ventilated and cold storage (Tindal 1983).

Table 4.11. Storage methods and length of storage used in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) (N=10) Descriptions Percent (%) Percent (%) Percent (%) Percent (%) Storage of onion Yes 60 10 10 26.7 No 40 90 90 73.3 Types of storage Bags (Jonya) 20 30 10 20 Spread on the floor 70 60 80 70 Put under the roof 10 10 10 10 Length of storage 1-2 weeks 70 50 80 70 3-4 weeks 20 30 20 23.3 >4 weeks 10 10 0 6.7

4.1.5 Onion crop water productivity

According to the survey results the average area used for onion production in the study area was about 0.5 ha of land (Table 4.12). From this area on average about 42.8 quintals of onion were obtained. Accordingly the productivity of onion in interviewed farmer`s farm land was about 85.6 qt ha-1. The productivity of onion in the study area is relatively low compared to the national average which is 101 qt /ha-1 as indicated by CSA (2015). The average total quantity of water used by respondents was about 4,914 m3 ha-1 which is in line with the recommendation of Seleshi Bekele et al. (2009) who found that about 3500-5550 m3 ha-1 of water is required throughout the growing season for optimum yield of onion crops.

The average onion water productivity in the study area was accordingly about 1.74 kg m-3. The crop water productivity obtained in this study is relatively low (1.74 kg m-3 ) compared to the crop water productivity obtained by the findings of Muuz G/Tsadik et al. (2012) two consecutive years average result which was about 4.62 kg/ m-3 of water.

Although the amount of water used by the respondents is in the range indicated by Seleshi Bekele et al. (2009) for optimum production of onion, the yield obtained from the respondents were low result which was low crop water productivity obtained in this study. This indicates that poor agronomic and cultural practices, Limited supply of seeds of improved onion varieties, high incidence of diseases and insect pests, decline of soil fertility and lack of training, weak extension and credit services employed by the farmers resulted low yield of onion which in turn reduced the crop water productivity in the study area (Muuz G/Tsadik et al.2012).

Table 4.12. Onion and water productivity in the study area

Sufankara Guramba Debir Zuriya Total (N=10) Michael (N=10) (N= 30) (N=10) Descriptions Mean Mean Mean Mean

Area allocated for 0.35 0.75 0.4 0.5 onion production (ha) Bulb yield in quintal 31.4 63 34 42.8 Onion productivity 89.71 84 85 85.6 (q/ha) Total water used (m3 ) 2,034 3,208 2,130 2,457

Total water used 5811.43 4277.33 5,325 4,914 (m3/ha) crop water productivity 1.54 1.96 1.59 1.74 kg/ m3

4.1.6 Major constraints of onion production in the study area

There are factors that limited onion production practices in Dembyia District. There were 30 participants during the study. About 30% of the interviewed onion producers were informed that: soil infertility, shortage of water, shortage of human labor, weak extension service, poor management of product, in availability of credits services and unfair market price for the product. Whereas 33.3 % of the interviewed onion producers were replied 38

that:, outbreak of disease and pest, limited supply of improved seed, market problem, the amount of water and seasonality of rivers, lack of training, adulteration of chemicals, high maintenance cost of motor pump were the constraints for the yield of onion. The remaining 36.7% of the interviewed onion producers were complained that :- shortage of land, crop rotation, high cost of oil and fuel, high purchasing cost of motor pump, shortage of genuine spare part, scarcity of chemicals and, lack of storage for the product.

The opportunities which may contribute to the development of onion production in the study area there is Farmers' awareness of the benefits, high irrigation production experience, surface irrigation water potentials and high production labor forces.

Soil analysis

According to soil analysis results, the experimental soil is heavy clay and basic in reaction (pH 7.24). Based on Bremner and Mulvancy (1982), the total nitrogen content of the soil can be categorized as medium. However, the soil has high available phosphorus content as described by Olsen et al. (1954). According to Walkley and Black (1934) the experimental soil has low organic matter contents whereas its cation exchanges capacity is considered as high (Black, 1965). The pH value of the experimental soil is around neutral. Generally, the experimental soil is suitable in all its properties for the production of onion Table 4.13).

Table 4.13.Analysis results of the experimental soil

Soil Type Ph Organic Total Total phosphorous CEC EC Value matter % Nitrogen % mg kg-1 Cmo1kg-1 ms/cm clay 7.24 1.87 0.107 18.02 48.5138 0.06

4.2. Effects of N:P2O5:S Fertilizers on Yield and Yield Components of Onion

The effects of different rates of N:P2O5:S fertilizer on vegetative growth and yield of onion is presented and discussed in this chapter. The effects of N: P2O5:S fertilizer on vegetative growth of onion is presented under subtitle 4.2.1 while its effect on yield performance of onion is presented under subtitle 4.2.2. The cost-benefit analysis of the different rates of N:P2O5:S fertilizer is presented under subtitle 4.2.3 below.

4.2.1 Vegetative growth parameters of onion

Plant height

The application of N:P2O5:S fertilizer generally increased the plant height of onion significantly (P<0.05). However, the longest plant height (60.07 cm) was obtained by -1 application of N:P2O5:S rates with the rate of 73.5:92:16.95 kg ha (T5) as indicated in

Table 4.4). The height of plants supplied with above mentioned rate of N:P2O5:S fertilizer was however similar with those supplied with T9 and T12 (Table 4.14). Onion plants without N: P2O5:S fertilizer were generally shorter compared to the others. The increase in plant height of onion may be due to the fact that onion is a sulfur loving plant which is required for proper growth and development of onion (Bloem et al., 2004). Nitrogen is an important building block of amino acids and formation of proteins required for plant growth (Bungard et al., 1999).

Leaf length and diameter

The length and diameter of onion leaves were significantly (P<0.05) influenced by the application of different rates of N:P2O5:S fertilizer (Table 4.14). Generally, the lengths and diameters of onion leaf were increased with increasing nitrogen levels. The longest (51.07 cm) and the widest diameter of leaves were obtained in treatment 12 where onion -1 plants were supplied with 136.5:119.6:22 kg ha of N: P2O5:S fertilizer (Table 4.4), while the shortest and narrowest leaves were observed in the control plot (44.3 cm). Compared to the control plants supplied with the above mentioned rates of N:P2O5:S fertilizer increased the leaf length by 15.2% and leaf diameter by 8.3%.

The increase in length and diameter of onion leaves may be due to the fact that nitrogen is important for division and elongation of plant cells (Brady, 1985, Marschner, 1995). Moreover, nitrogen plays on chlorophyll, enzymes and proteins synthesis which are important for plant growth. In this regard Bungard et al. (1999) described that nitrogen is the major constituent of proteins and its abundant presence tends to increase the size of the leaves, and accordingly bring about an increase in carbohydrate synthesis. The result is in agreement with Muhammad (2004) and Jilani (2004) who reported that the length and width of onion leaves increased with the increasing nitrogen rates.

Leaf number

The application of N:P2O5:S fertilizer generally increased the number of onion leaves.

However, the increment of leaf number along with the different levels of N: P2O5:S fertilizer was not statistically significant (P>0.05). Nevertheless, the lowest number of leaves (12.60) was recorded in control plants where no N:P2O5:S fertilizer was applied (Table 4.14). These results disagree with the findings of Nasreen et al. (2007) who found that application of 120 kg N ha-1 significantly increased the number of onion leaves per plant. They also found that further increase in the level of N (160 kg ha-1) tend to decrease the leaf number (Nasreen et al. 2007). Similarly, Vachhani and Patel (1993) found that the number of onion leaves per plant was highest with the application of 150 kg N ha-1.

Fresh and dry weight of above ground biomass

The fresh and dry weight of the above ground biomass of onion was not significantly

(P>0.05) influenced by the application of different rates of N:P2O5:S fertilizer rates (Table 4.14). The highest fresh and dry weights of the above ground biomass of onion plant were -1 however recorded in treatment 10 where 136.5:64.4:11.86 kg ha of N:P2O5:S fertilizer was applied with the mean values of 51.83g and 5.20g, respectively. The lowest fresh (34g) and dry (2.96) weights were recorded in control plot. The present study is disagree with Nasreen et al. (2007) and El-Tantawy and El-Beik (2009) they indicated that application of higher N doses ha-1 increased dry total biomass yields of onion.

80% maturity days

A maturity date of onion was highly significantly (P<0.01) influenced by the application of different rates of N:P2O5:S fertilizer rates as indicated in (Table 4.14). The highest numbers of days was recorded in treatment 12 (142 days) which was supplied with -1 136.5:119.6:22 kg ha N:P2O5:S fertilizer rate. The lowest number of maturity days was recorded in treatment 1 (137 days). This could be associated with the effect of nitrogen in extending the vegetative growth period of plants while delaying the maturity. The results are in agreement with the finding of Yamasaki and Tanaka (2005) who observed that the extended vegetative growth period of plants with higher rates of nitrogen. Similarly Brewester (1994) and Sørensen and Grevsen (2001) observed that too much nitrogen promoted excessive vegetative growth and delayed maturity.

Table 4.14. The vegetative growth of onion as influenced by different N:P2O5:S rates

Treatments PH LL LD LN FW DW DM (cm) (cm) (cm) g/plant g/plant % T1 (0:0:0) 50.30e 44.33d 1.33d 12.60 34.00 2.96 137.00f T2 (24.96:28.52:0) 52.37de 45.60cd 1.36cd 13.20 44.33 3.96 137..33f T3 (105:92:0) 55.03cd 48.40abc 1.43ab 14.03 39.00 3.53 137.33f T4 (73.5:64.4:11.86) 55.73bcd 48.73abc 1.43ab 14.10 44.16 3.70 137.66ef T5 (73.5:92:16.95) 60.07a 49.03ab 1.41abc 14.76 41.33 3.53 139.00cde T6 (73.5:119.6:22) 55.37bcd 48.03abc 1.38bcd 12.63 42.16 3.93 138.00def T7 (105:64.4:11.86) 53.47cde 46.70bcd 1.37cd 13.53 41.16 3.56 139.33cd T8 (105:92:16.95) 55.37bcd 49.07ab 1.43ab 16.20 38.00 3.73 137.67ef T9 (105:119.6:22) 57.10abc 50.07a 1.37cd 13.90 50.33 4.06 140.00bc T10(136.5:64.4:11.86) 56.07bcd 48.60abc 1.41abc 13.73 51.83 5.20 141.00bc T11 (136.5:92:16.95) 54.30cd 47.80abc 1.40abc 13.76 46.16 3.86 141.33ab T12 (136.5:119.6:22) 59.10ab 51.07a 1.44a 14.70 45.33 3.80 142.00a

SE± 1.23 1.10 0.02 1.02 5.02 0.29 0.42 Mean 55.36 48.11 1.39 13.93 43.15 3.82 138.89 Sig. Difference * * * NS NS NS ** CV 4.11 4.12 2.27 12.60 22.53 16.82 0.66

Key;-NS= non significance difference; ** highly significant, *Significant; DF= degree of freedom; CV= coefficient of variation; PH= plant height; LL= leave length; LD= leave diameter; LN=leave number; FW= Fresh weight; DW= Dry weight; DM= Days to 80% maturity.

4.2.2. Yield and yield parameters of onion

The effects of different rates of N:P2O5:S on yield and yield parameters of onion is presented in Table 4.5 and discussed as follow.

Onion bulb weight

Onion bulb weight was highly significantly (P<0.01) influenced by the application of different rates of N:P2O5:S fertilizer. Significantly maximum bulb weight (198.83g) was -1 obtained in treatment nine where 105:119.6:22 kg ha N:P2O5:S rate was applied. The bulb weight of those onions was however similar to those obtained from treatment twelve. The minimum onion bulb weight (132.5g) was recorded in control plants without N:

P2O5:S fertilizer (Table 4.15). The increment of the bulb weight in T9 was about 50.1% compared to the control. The result is in agreement with the findings of Ahmed, et al. (1988) who reported that the weights of onion bulbs were significantly improved with the

application of sulfur up to 24 kg ha-1. They further reported that the bulb weight is positively related with the yield of onion which was also observed in this study.

Onion bulb length and diameter

The length and diameter of onion bulbs were not significantly (P>0.05) influenced by the application of different rates of N:P2O5:S fertilizer. However an increasing trend in length and diameter of onion bulbs was observed with increasing phosphorous and sulfur concentrations especially at higher nitrogen levels. Accordingly, the longest and widest onion bulbs were obtained in treatment nine and twelve of this study, respectively (Table 4.15). In both parameters, bulbs obtained from control plants were inferior. In some extent the results of this study is in agreement with the results of Yadav et al. (2003) and Reddy and Reddy (2005) who found an increase of onion bulb length in response of nitrogen fertilizers.

Bulb yields of onion

Marketable bulb yield of onion was highly significantly (P<0.01) influenced by the application of different rates of N:P2O5:S. The application of sulfur in the form of N:

P2O5:S generally increased the marketable yield of onion. The highest marketable bulb -1 yields of onion were obtained from T9 (105:119.6:22 N:P2O5:S kg ha ) followed by T12 -1 -1 (136.5:119.6:22 N:P2O5:S kg ha ) and T11 (136.5:92:16.95 N:P2O5:S kg ha ) with the mean values of 20.9, 20.3 and 19.70 t ha-1, respectively, where by the mean values were similar (P<0.01). But when compared to the national productivity which is 101 tone and farmers practice 8.4 tone. The lowest significant (P<0.01) marketable bulb yield (10.4 t ha- 1 ) was recorded from the control treatment where no N:P2O5:S rate was applied (Table 4.15).

Similar trend was also observed in total bulb yield of onion in T9, T12 and T11 with the mean values of 21.4, 20.8, and 20.2t ha-1, respectively, which were not statistically different when compared each other. The total bulb yield of onion in control treatment was also significantly (P<0.01) the lowest yield (10.6t ha-1) obtained in this study. In case of unmarketable yield, the highest unmarketable yield was obtained from T9 followed by T12 and T11 with the mean values of 0.51, 0.49 and 0.48 t ha-1, respectively (Table 4.15).

The results of the present study revealed that yield and yield parameters of onion were influenced with the different rates of N:P2O5:S. The highest marketable, unmarketable and total yields of onion were generally obtained from the application of highest rates of phosphorous and sulfur. Furthermore sulfur and nitrogen stimulate the enzymatic actions and chlorophyll formation which promote the growth and development leading to high yielding performance of plants (El-Shafie and El-Gamaily, 2002). Thus an adequate supply of nutrients to plants is associated with vigorous vegetative growth resulting higher productivity of crops (Yadav, et al., 2003).

Moreover, onion is a sulfur loving vegetable crop where its growth and development and its quality is positively affected by sulfur (Bloem et al., 2004). On the other hand, application of sulfur to the soil may modify pH value, improve soil-water relation and increase the availability of nutrients like P, Fe, Mn and Zn (Marschner, 1998) which may contribute to the increase in bulb yield of onion.

The results obtained in this study is in conformity with the findings of Ahmed, et al. (1988) that reported the application of sulfur up to 24 kg ha-1 significantly improved the bulb weight and yields of onion. They further reported non-application of sulfur in deficient soils resulted restricted shoot growth, stiffed stem and woody and small sized bulbs which resulted low yield of onion. However excess sulfur may also increase onion pungency which may be undesirable for fresh market. Cizauskas et al. (2003), Hansen and Heneriksen (2001) in their studies found the increase of marketable yields of onion with the application of nitrogen in the range of 60-150 kg ha-1 which is in agreement with the results of this study. Singh et al. (1989) also found that application of 120 kg Nitrogen gave the best onion bulb yield. Similar results also reported by Vachhanni and Patel (1993), Vachhanni and Patel (1994), and Pandey and Ekpo, (1991).

Similarly, the application of sulfur also increased yield and yield parameters of other vegetables. In this regard, Shege Getu (2015) unpublished reported that bulb weight, diameter and length of garlic were increased with the application of sulfur in the form of

N:P2O5:S.

Table 4.15.Yield parameters of onion as influenced by different N:P2O5:S rates

Treatments BW BL BD MBY UMBY TBY (g) (cm) (cm) (t/ha) (t/ha) (t/ha) 1. 0:0:0 132.50i 6.63 6.44 10.385c 0.174b 10.559c 2. 24.96:28.52:0 153.47h 6.80 6.90 12.841c 0.466a 13.380c 3. 105:92:0 186.00e 6.87 6.66 18.850ab 0.459a 19.310ab 4. 73.5:64.4:11.86 178.00f 6.91 6.72 18.213ab 0.444a 18.658ab 5. 73.5:92:16.95 188.50e 6.80 6.87 18.442ab 0.449a 18.892ab 6. 73.5:119.6:22 174.50g 7.00 6.59 17.592b 0.429a 18.021b 7. 105:64.4:11.86 176.83fg 6.82 6.58 17.899ab 0.436a 18.335ab 8. 105:92:16.95 191.83cd 6.98 6.83 19.258ab 0.469a 19.727ab 9. 105:119.6:22 198.83a 7.15 6.87 20.888a 0.509a 21.398a 10.136.5:64.4:11.86 188.83de 6.80 6.79 18,978ab 0.462a 19.441ab 11.136.5:92:16.95 193.67bc 6.75 7.01 19.704ab 0.480a 20.185ab 12.136.5:119.6:22 196.33ab 6.69 7.10 20.287ab 0.494a 20.781ab SE± 0.90 0.16 0.21 10.94 0.35 11.13 Mean 179.94 6.85 6.78 177.78 4.39 18.21 Sig.Difference ** NS NS ** ** ** CV 0.10 4.79 4.95 10.00 12.26 9.93 Key; - NS= non significance difference; ** highly significance difference, *Significance difference; DF= degree of freedom; CV= coefficient of variation; BW= bulb weight; BL= bulb length; BD= bulb diameter; MBY= marketable bulb yield; UMBY= non marketable bulb yield; TBY= total bulb yield

4.2.3. Marginal rate of return of onion as affected by N: P2O5:S fertilizer rates

Marginal rate of return was analyzed using the technique described by CIMMYT (1988) to assess the costs and benefits of the treatments. Therefore, first the costs, gross incomes and net profits of N: P2O5:S fertilizer rates were calculated as indicated in Table 4.16. In calculating marginal rate of return (MRR), the marketable yields of onion in each treatment were used. The highest marginal rate of return was obtained from onion plants -1 applied by 24.96:28.52:0 kg ha of N:P2O5:S followed by those applied by 105: 92:16.95 -1 kg ha of N:P2O5:S (Table 4.17.) with the values of 13724.2 and 5213.89 %, respectively. The relative least marginal rate of return was recorded in the application of 73.5:92:16.95 -1 kg ha of N:P2O5:S with the value of 408.14%.

Table 4.16. Cost gross income and net profit of onion as influenced by N: P2O5:S fertilizer rates in Dembyia District

Variable cost per ha. Income per ha. Treatments Fertilizer cost per ha Eth-birr LC in TVC in Eth- MBY GI Eth birr GI – TVC (Net Eth birr birr benefit) N:P2O5:S DAP UREA N: P2O5:S (ton/ ha) T1. 0:0:0 0 0 0 0 0 10.385 155775.0 155775.0

T2 24.96:28.52:0 3138 1780.5 0 210 5128.5 18.85 277621.5 277831.5 T3 105:92:0 972.78 351.1 0 350 1673.9 12.841 190941.1 191286.1 T4 73.5:64.4: 11.86 0 1065.72 2408.221 490 3963.9 18.213 269231.1 269721.1 T5 73.5:92:16.95 0 709.6196 3440.316 560 4709.9 18.442 271920.1 272480.1 T6 73.5:119.6:22 0 353.5196 4472.411 700 5525.9 17.592 258354.1 259054.1 T7 105:64.4:11.86 0 1878.557 2408.221 560 4846.8 17.899 263638.2 264198.2 T8 105: 92:16.95 0 1522.457 3440.316 630 5592.8 19.258 283277.2 283907.2 T9 105:119.6:22 0 1166.357 4472.411 700 6338.8 20.888 306981.2 307681.2 T10 136.5:64.4:11.86 0 2691.393 2408.221 490 5589.6 18.978 279080.4 279570.4 T11 136.5:92:16.95 0 2335.293 3440.316 560 6335.6 19.704 289224.4 289784.4 T12 136.5:119.6:22 0 1979.193 4472.411 700 7151.6 20.287 297153.4 297853.4

Key: - LC: = labor cost, TVC: = total variable cost, MBY: = marketable bulb yield, GI: = gross income

Cost of N: P2O5:S per quintal =1404 Birr, DAP per quintal =1540 Birr, UREA per quintal =1172 Birr, cost of onion per kg = 15 Birr, labor cost per man-day =70 Birr

Table 4.17. Marginal rate of return (MRR) of N: P2O5:S fertilizer rates in Dembyia District

Treatments Cost Net profit MRR (%) Rank T1 = 0 : 0 : 0 0 155775 - 6 T4 = 73.5:64.4: 11.86 3963.9 269721.1 3425.11 5 T2 = 24.96:28.52:0 5128.5 277831.5 4839.65 4 T10 =136.5:64.4:11.86 5589.6 279570.4 32207.69 3 T8 = 105: 92:16.95 5592.8 283907.2 135525.00 2 T9 = 105:119.6:22 6338.8 307681.2 559275.00 1

Key; - MRR- Marginal Rate of Return

CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS

5.1. Conclusions

Onion is one of the most important vegetable crops cultivated throughout the country. The production and productivity of onion in Dembiya District had been increased in Ethiopia over the last five years due to the increase attention of the government to irrigation facility. However production and productivity is by far lower compared to other countries. Intervention on this low level of onion production requires various information about the production practices employed by farmers and thus identification of the major constraints and opportunities of the crop including in the study kebele. On the other hand, the Ministry of Agriculture introduced N:P2O5:S new fertilizer in crop production system which contains nitrogen, phosphorous and sulfur where its optimum rate of application is not yet identified. Therefore, the main aim of this study was to assess the farmer`s production practices and to investigate the effects of N:P2O5:S fertilizer on growth and yield performance of onion in the study area.

Onion is produced mainly during off season using irrigation in the study kebeles where Adama red and Bombay red were the dominant varieties grown by the framers. Although farmers have relatively long experiences, in most cases they don’t implement the recommended cultural practices for the production of onion. Among others, they employ broadcasting methods to sow onion seeds in the seedbed and transplant seedlings early in the morning hours that may expose seedlings to the coming strong sunlight which affects their establishment in the field. Most of the farmers in the study area are not using the recommended rates, time and methods of DAP and urea fertilizers. Furthermore, the frequency and amount of irrigation is not based on the requirements of the plants.

Framers in the study area produce onion for market and they sale their products to different customers such as wholesalers, retailers and consumers without long storage practice. Selling of the onion at the time of surplus production may reduce the expected return of the farmers because of low price level at this which was also observed in this study.

The onion production in the study area is facing from various constraints. Among others, high costs of irrigation equipments, shortage of genuine spare parts and accessories, shortage of pesticides and their adulteration, limited supply improved onion seeds and lack of storage facilities, lack of skills and knowledge, high incidence of diseases and insect pests and weak extension and credit services are the most important once.

The application of N:P2O5:S fertilizer in this study affected almost all the growth and yield parameters of onion. Among the vegetative growth parameters, plant height, leaf length and diameter and days to 80% maturity of onion were influenced by N:P2O5:S rate.

Moreover, the yield of onion was also affected by different rates of N:P2O5:S. The -1 application of N:P2O5:S at the rate of 105:119.6:22 kg ha (T9) gave the highest marketable yield of onion (20.9 t ha-1) which was statistically similar with the yields obtained from T12 (20.3 t ha-1), T11 (19.7 t ha-1) and T8 (19.3 t ha-1). The highest marginal rate of return however was obtained from onion plants supplied with N:P2O5:S fertilizer rate of 105:119.6:22 kg ha-1 (T9).

5.2. Recommendations

The above findings indicated that Dembiya district has a huge potential for onion production. Therefore onion production in the study area should be intensified and diversified to satisfy the wider regional market demand and to gain normal profit for all onion producers. However, onion producers in the area lack to some extent skills and knowledge in proper agronomic and post harvest handling practices necessary to obtain high onion yield and to reduce postharvest losses. Therefore, continuous training and extension services should be given by the respective stakeholders such as agricultural offices, universities and concerned non-governmental organizations.

Moreover, the supply of inputs such as improved seeds, pesticides and irrigation equipments and its accessories should be improved. For this purpose it is necessary to support the private and cooperative input suppliers and create a strong institutional linkage between input suppliers and farmers. To solve the financial problem of the farmers, it is also recommended to create a strong linkage between farmers and financial institutions.

Furthermore, the highest yield and marginal rate of return was obtained from of onion was at Dembyia district can be increased by application of N:P2O5:S fertilizer at the rate of 105:119.6:22 kg ha-1 (T9). To develop forceful recommendation however, it is advised to repeat the experiment on soils of different characteristics and agro-ecological conditions using different improved onion varieties.

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APPENDIX

Appendix Table 1. ANOVA Table for plant height

Source of variation Df SS MS F value Pr>value Trt 11 237.56 21.60 4.18 0.0021 Rep 2 0.92 0.46 0.09 0.9155 Error 22 113.66 5.17 Total 35 352.14 CV (%) 4.11 R2 (%) 0.68 LSD 3.85

Appendix Table 2. ANOVA Table for leaf length

Source of variation Df SS MS F value Pr>value Trt 11 113.12 10.28 2.62 0.0264 Rep 2 21.51 10.76 2.74 0.0869 Error 22 86.49 3.93 Total 35 221.12 CV (%) 4.12 R2 (%) 0.61 LSD 3.36

Appendix Table 3. ANOVA Table for leaf diameter

Source of variation Df SS MS F value Pr>value Trt 11 0.03896 0.00354 3.51 0.0059 Rep 2 0.00007 0.00004 0.04 0.9649 Error 22 0.02219 0.00101 Total 35 0.26093 CV (%) 2.27 R2 (%) 0.64 LSD 0.05

Appendix Table 4. ANOVA Table for date of maturity

Source of variation Df SS MS F value Pr>value Trt 11 91.56 8.32 9.84 <0.0001 Rep 2 9.39 1.69 2.00 0.1588 Error 22 18.61 0.85 Total 35 119.56 CV (%) 0.66 R2 (%) 0.84 LSD 1.56

Appendix Table 5. ANOVA Table for bulb weight

Source of variation Df SS MS F value Pr>value Trt 11 12417.18 1128.83 349.56 <0.0001 Rep 2 2.46 1.23 0.38 0.6875 Error 22 71.05 3.23

Total 35 12490.69 CV (%) 0.10

R2 (%) 0.10 LSD 3.04

Appendix Table 6. ANOVA Table for marketable bulb yield

Source of variation Df SS MS F value Pr>value Trt 11 31248.03 2840.73 8.98 <0.0001 Rep 2 3288.89 1644.45 5.20 0.0141 Error 22 6956.43 316.20

Total 35 41493.35

CV (%) 10.00

R2 (%) 0.83

LSD 30.11

Appendix Table 7. ANOVA Table for unmarketable bulb yield

Source of variation Df SS MS F value Pr>value Trt 11 24.85 2.26 7.78 <0.0001 Rep 2 3.96 1.98 6.82 0.0050 Error 22 6.39 0.29

Total 35 35.20

CV (%) 12.25

R2 (%) 0.82 LSD 0.91

Appendix Table 8. ANOVA Table for total bulb yield

Source of variation Df SS MS F value Pr>value Trt 11 32693.75 2972.16 9.08 <0.0001 Rep 2 3500.77 1750.38 5.34 0.0128 Error 22 7205.06 327.50

Total 35 43399.58

CV (%) 9.93

R2 (%) 0.83 LSD 30.64

ANNEX

I. Demographic information

1. Name of farmer ------2. Sex of the household heads 1. Female 2.Male 3. Age of the households 1. 18 years 2. 19 – 33 years 3. 33 – 48 years 4. > 48 years 4. Religious status 1. Orthodox 2.Muslim 3.protestant 4. Catholic 5. Others 5. Marital status 1. Single 2.Married 3. Divorced 6. Family size 1. > 4 family members 2. < 4 family members 7. Educational status of the household heads 1. Literate 2. Illiterate 3. 1 – 6 grade 3.8 – 10 grade 4. Others

II. Farm practices 1. Total land holding of the household 1.0.5 Ha. 2.0.5 – 1 ha 3. 1 – 1.5 ha 4. >1.5 ha 2. Amount of land used for onion production 1. 0.25 ha. 2. 0.25 - 0.5 ha 3. 0.5 – 0.75 ha 4. 1 ha 5. > 1 ha. 3. Have you ever produced onion seed? 1. Yes 2. No 4. Where do you get your onion seed from? 1. Farmers shops 2. BoA 3. Owen seeds 4. Others 5. Which variety of onion do you produce? 1. Adama Red 2. Bombay Red 3.Red Creole 4.Other

6. When do you grow onion? 1. During offseason of irrigation 2.crroping seasons 3. Both

7. Which methods of planting do you follow for onion? 1. Direct sowing 2.Raised seedling and Transplanting 3. Both 8. At which stages are seedlings are ready to transplanting? 1. Two leaves stages 2. Four leaves stages 3.At 10 cm 4. At 15 cm 9. How long do you wait for seedling to transplant? 1. Four weeks 2. Five weeks 3. Six weeks 4. Seven weeks 5. > 7 weeks 10. What is the spacing do you use by planting onion in the field? 1. 10 x 20 cm 2.10 x 20 x 40 cm 3. Others 11. At what time of the day do you transplant onion seedling? 1. Early morning 2. Noon time 3. Late evening 4. Others 12. Do you use inorganic fertilizers? 1. Yes 2. No 13. How much DAP kg/ha do you apply? 1.5 kg 2. 10 kg 3. 25 kg 4.50 kg 5. 100 kg 14. When do you apply DAP? 1. During planting 2. After planting 3. Both 15. How much UREA kg/ha do you apply? 1.5 kg 2. 10 kg 3. 25 kg 4.50 kg 16. When do you apply UREA? 1. During planting 2. After planting 3. Both 17. Do you use organic fertilizer to produce onion? 1. Yes 2. No 18. How much compost do you apply qt/ha? 1. 1 qt/ha 2. 2 qt/ha 3. 5 qt/ha 4. 10 qt/ ha 5. Others 19. When do you apply compost? 1. before planting 2. At planting 3. After planting 20. Methods of application? 1. Broadcasting before planting 2. Side dressing after planting 3.Both 21. How much manure do you apply qt/ha? 1. 1 qt/ha 2. 2 qt/ha 3. 5 qt/ha 4. 10 qt/ ha 5. Others 67

22. When do you apply manure? 1. before planting 2. At planting 3. After planting

23. Methods of application? 1. Broadcasting before planting 2. Side dressing after planting 3.Both 24. How long is your experience in onion production? 1. 5 Years 2. 10 Years 3. 10 – 15 Years 4. > 15 Years 25. How many times in a year do you produced onion? 1. Once 2. Twice 3. Trice 26. What is Your source of irrigation water for cultivation? 1. Rain 2. Rivers 3. Spring 4. Others 27. Which methods of irrigation do you use? 1. Water cane 2. Furrow irrigation 3. Flood irrigation 4. Others 28. How frequently do you irrigate your onion? 1.Every week 2. Every two weeks 3. Every three weeks 4. Others 29. Do you practice crop rotation? 1. Yes 2. No 30. What kinds of diseases observed in your onion plants? 1. Black leg 2. Club rot 3. Leaf spot 4. Others 31. What measures did you take? 1. Chemical spray 2. Cultural practice 3. Using improved seeds 32. What kinds of insect pest observed in your onion plants? 1. Cut worm 2. Thrips 3. Beetles 4. Others 33. What measures did you take? 1. Insecticides spray 2. Cultural practice 3. Others

III. Harvesting and post harvest operation 34. How long does onion takes to reaches harvest maturity? 1. Three months 2. Four months 3. Five months 4. > Five months 35. How do you know when onion is ready to harvest? 1. Color of the leaves 2. Number of days 3. Bulb sizes 4. Others 36. How do you harvest onion? 1. By fork 2. Sickle 3. Uprooting 4. Others 68

37. What time of the day are you harvesting your onion? 1. Early morning 2. Mid day 3. Late evening 4. Others 38. How much yield do you produce in a given area? 1. 60 qt/ha 2. 70 qt/ha 3. 80 qt/ha 4. 90 qt/ha 5. > 90 qt/ha 39. Do you practice curing of onion after harvesting? 1. Yes 2. No 40. If you yes, how many days do you need curing? 1. One week 2. Two weeks 3. Three weeks 4. Four weeks 5. Others 41. If you yes, what types of curing methods do you need? 1. Heaping 2. Left on the farm field 3.Press the top part 4.Put on the roof 42. Do you store your onion? 1. Yes 2. No 43. How do you store your onion? 1. Spread on the floor 2. Bags Put under the bed 4. Others 44. For how long can you store your onion? 1. One weeks 2. Two weeks 3. Three weeks 4. Others 45. What is the purpose of your onion production? 1. for marketing 2. Consumption 3. Both 46. To whom do you sell your onion? 1. Consumers 2. Retailers 3. Whole sellers 4. Brokers 47. What is the price of onion in shortage of time? 1. < 5 birr per kg 2. 10 birr per kg 3. 13 birr per kg 4. 15 birr per kg 48. What is the price of onion in surplus time? 1. < 5 birr per kg 2. > 5birr per kg 3. 13 birr per kg 4. Others 49. How far do you travel? 1. One hour 2. Two hours 3. Three hours 4. Four hours 5. Others 50. How do you take your onion to the market? 1. By head load 2. By pack animals 3. By vehicles 4. Others 51. In the last three years did you received any kinds of training on onion production? 1. Yes 2. No 52. If, yes to whom? 1. Universities 2. BoA 3. Research center 4. NGOs 5. Others 53. Have you ever received any kinds of credit for onion production? 1. Yes 2. No 69

54. If, yes to whom? 1. Universities 2. BoA 3. Research center 4. NGOs 5. Others 55. Did you receive extension service for onion production? 1. Yes 2. No 56. If, yes to whom? 1. Universities 2. BoA 3. Research center 4. NGOs 5. Others 57. Did you have any advice for onion production? 1. Yes 2. No 58. If, yes to whom? 1. Universities 2. BoA 3. Research center 4. NGOs 5. Others 59. What are the general problems in the production of onion?

60. For this question you have to list the problems and let the farmer prioritize?

61. What should be done to solve these problems?

BIOGRAPHIC SKETCH

The author, Mr.Muluneh Nigatu was born in September 22, 1972 in Chilga Woreda, North Gondar Administrative Zone, Ethiopia. From 1980 to1987, he attended elementary school at Chilga Junior elementary school, from 1988 to 1991 at Azezo Senior Secondary School. In 1992 he joined Jimma University College of Agriculture and graduated with Diploma in General Agriculture in 1993. In 1995 he was employed by Amhara Regional State Bureau of Agriculture and has worked as an agronomist in the North Gondar Zone Adiarkay Woreda office of Agriculture. In 1999 he joined Jimma University College of Agriculture and Veterinary Medicine and graduated with B.Sc. degree in Horticulture in 2002. Later, he was employed by Dembiya Woreda Agricultural Development office in 2002. He joined the post Graduate Studies, in Bahir Dar University College of Agriculture and Environmental Science, for M.Sc. Degree in Horticulture in 2006.