Experimental Analysis of the Suitability of Ducks, Fish and Field Border Plants in Complex Rice Systems in Lima Puluh Kota Regency, Indonesia

MSc Thesis Report

Supervisor: dr.ir.JCJ (Jeroen) Groot and Uma Khumairoh, MSc

Andre Sparta 840917788100

FSE-80436 Farming System Ecology

MSc program Plant Science Specialization Natural Resource Management Wageningen University, the Netherlands

2018

Experimental Analysis of the Suitability of Ducks, Fish and Field Border Plants in Complex Rice Systems in Lima Puluh Kota Regency, Indonesia

Student Name : Andre Sparta Reg. Number : 840917788100 Credits : 36 ECTS Course code (name) : FSE-80436 Period : July 2017 - April 2018 Supervisors : dr. ir. JCJ. Groot and Uma Khumairoh,MSc Examiner : Prof.dr. ir. R. Schulte

ii Table of Contents

List of tables ...... iv

List of figures ...... v

List of Supplementary Materials ...... vii

Acknowledgment ...... viii

Abstract ...... ix

Introduction ...... 1

Objective ...... 2

Research Questions ...... 2

Hypotheses ...... 2

Materials and Methods ...... 3 Experimental site ...... 3 Material ...... 3 Experimental Design ...... 4 Cultivation Methods ...... 6 Observation and Sampling ...... 7 Plant Growth, Development, and Yield ...... 7 Pest and Weed Population ...... 7 Economic Farm Performance ...... 8 Statistical Analyses ...... 8

RESULTS ...... 8 Plant Growth, Development, and Yield ...... 8 Pest and Weeds Population ...... 12 Pest Population ...... 12 Weed Population ...... 15 Economic farm performance ...... 16

Discussion ...... 18

Conclusion and Recommendation ...... 21

References ...... 22

Supplementary Material ...... 24

iii List of tables

Table 1. Yield components of rice plants in six treatments. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops...... 11

iv List of figures

Figure 1. Lima Puluh Kota regency, Source: google.com ...... 3 Figure 2. The materials used in the experiments. a Local ducks (Anas platyrhynchos). b Nile fish (Oreochromis niloticus). c Long beans (Phaseolus vulgaris). d Sunn hemp (Crotalaria juncea) ...... 4 Figure 3. Design layout of experiments. The box in the center of the plots: yield components observation; the box around the center of the plot: plant growth and development observations...... 5 Figure 4. Land preparation...... 6 Figure 5. Plant height (cm) of rice plants at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S3 for analysis of significance of differences...... 8 Figure 6. Tiller number of rice plants at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS organic complex rice system with ducks, fish, and border crops. See Table S4 for analysis of significance of differences...... 9 Figure 7. Leaf area index and specific leaf area of rice plant at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; ; CRS, organic complex rice system with ducks, fish, and border crops. See Tables S5 and S6 for analysis of significance of differences...... 10 Figure 8. Dry matter of rice plant at 28, 49, 70, 84, and 105 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S7 for analysis of significance of differences...... 10 Figure 9. Dry matter above and below ground of rice plant at generative phase. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S8 for analysis of significance of differences...... 11 Figure 10. N, P, and K uptake of rice grain at generative phase. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S9 for analysis of significance of differences...... 12 Figure 11. a) Stem borer abundance, b) Green leaf hoppers abundance, c) Other leaf hoppers abundance, d) Flies abundance, e) Rice bugs abundance, and f) Snail abundance at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Tables S10, S11, S12, S13, S14, and S15 for analysis of significance of differences...... 14 Figure 12. Dry matter and abundance of the weeds at 3 and 6 weeks after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks CRS, organic complex rice

v system with ducks, fish, and border crops. See Tables S18 and S19 for analysis of significance of differences...... 15 Figure 13. . a) Farm cost, Farm revenue, and Farm gross margin (in millions of rupiah) from each system. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S23 for analysis of significance of differences...... 17

vi List of Supplementary Materials

Table S 1. Rainfall Data in Guguak Sub District (mm) ...... 24 Table S 2. Composition of Compost (%) ...... 24 Table S 3. Data of Plant Height (cm) ...... 24 Table S 4. Data of Tiller Number (per plant)...... 24 Table S 5. Data of Leaf Area Index (cm2 cm-2) ...... 24 Table S 6. Data of Specific Leaf Area (cm2 g-1) ...... 24 Table S 7. Data of Total Dry Matter (Above and below Ground) of Rice Plant (g/plant) ...... 25 Table S 8. Total Dry Matter Above-Ground and Below-Ground (g/plant) ...... 25 Table S 9. N, P, and K composition (%) and N, P, and K uptake (kg/ha) on rice grain ...... 25 Table S 10. Stem Borer (per plot) ...... 25 Table S 11. Green Leafhopper (per plot) ...... 26 Table S 12. Other Leaf Hopper (per plot) ...... 26 Table S 13. Flies (per plot) ...... 26 Table S 14. Rice Bugs (per plot) ...... 26 Table S 15. Snails (per plot) ...... 26 Table S 16. Dry Matter Total of Weed (g/m2) ...... 26 Table S 17. Abundance Total of Weeds ...... 27 Table S 18. Dry matter of weed species at 21 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops ...... 27 Table S 19. Weed species’ abundance at 21 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops ...... 28 Table S 20. Dry matter of weeds species at 42 day after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops ...... 28 Table S 21. Weed species abundance at 42 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops ...... 29 Table S 22. Weight of Ducks (kg/ha), Fish (kg/ha), and Long Beans (Mg/ha) ...... 29 Table S 23. Cost, Revenue, and Gross Margin of the farm (million rupiah) ...... 29 Table S 24. Distribution of Cost, Revenue, and Gross Margin of the farm (million rupiah) ...... 30 Table S 25. N Soil Analysis (%) ...... 30

vii Acknowledgment

The research “Experimental Analysis of the Suitability of Ducks, Fish and Field Border Plants in Complex Rice Systems in Lima Puluh Kota Regency, Indonesia” was conducted at Mungka, Lima Puluh Kota Regency from July 2017 to December 2017. In this research, I tried to introduce new methods of rice cultivation in Lima Puluh Kota Regency, Indonesia. First of all, I would like to give my acknowledgements to my supervisor, dr. J.C.J. Groot and Uma Khumairoh MSc for their supports and guidance during my thesis. My gratitude thanks to dr. J.C.J. Groot who taught me fundamental knowledge in this study. I appreciate to his advice and suggestion in my experiment since the research proposal until I finished my thesis. Many thanks are also delivered to Mbak Uma Khumairoh MSc who gave me opportunity to conduct this experiment. Also the guidance and support she granted on the fieldwork from the beginning of the experiments until I finished my thesis that made me understand a lot. Furthermore, I want to deliver many thanks to local farmers from Lima Puluh Kota regency for their assistance and contribution during the field work. They also shared their experience in rice cultivation which supported my experiments. I hope this thesis result will give benefits and better insights for local people especially farmers from Lima Puluh Kota regency. Finally, I deeply dedicate my special thanks to my wife and my family members for their supports and patient. Also, many thanks to my beloved friends that strongly contribute and support me for finishing my thesis as well as pursuing my dreams for this master degree.

viii Abstract

Rice productivity needs to be improved in response to the increasing food demand due to the rapid population growth. In Lima Puluh Kota regency, Indonesia, rice is used as the main food and as the main income source for small-scale farmers. Farmers in Lima Puluh Kota regency are characterized by having small farm area and limited capital. Complex Rice Systems (CRS) is an integrated farming approach that combines new technologies with traditional practices and knowledge to increase rice productivity in sustainable ways. In this experiment, we tried to introduce CRS in Lima Puluh Kota regency to find a better way to support food security of small- scale farmers. The purpose of this experiment was to investigate how rice crops and whole farm productivity are affected by different combinations of ducks, fish, and field borders in Lima Puluh Kota regency. This research was conducted at Mungka, Lima Puluh Kota Regency at an altitude of approximately 550 m above sea level and ran from July 2017 until December 2017. The materials used in this experiment were rice (Oryza sativa), duck (Anas platyrhynchos), fish (Oreochromis niloticus and Cyprinus carpio), sunn hemp (Crotalaria juncea) and long beans (Phaseolus vulgaris). The experimental design was a Randomized Complete Block Design with 6 treatments and 3 replication blocks. The treatments were: conventional rice (CON) system, organic rice (ORR) system, organic rice with border crops (ORB), organic rice with fish (ORF), organic rice with ducks (ORD), and the organic complex rice system with ducks, fish, and border crops (CRS). The experiment resulted in the better growth, development, and yield of rice plants in CRS and ORD. These two treatments also resulted in better pest and weed suppression in rice fields. The main key success of these two treatments was the presence of ducks in rice fields. In the beginning, the adding of ducks in rice fields increase the costs more than two times than conventional and organic systems. However, in the end calculation, the treatment that were integrated ducks in rice fields (ORD and CRS) resulted in higher gross margin than the other treatments. It is concluded that ducks have an important role in increasing the current rice productivity in the Lima Puluh Kota regency.

ix Introduction Rice is one of the staple foods that is consumed by many people in the world, especially in Indonesia. GRISP (2013) reported that the largest agricultural land-use in the world was rice farming and around 90% of total rice production was generated in Asia. “No day without rice”, this sentence describes the importance of rice among Indonesian people. They eat rice for daily meals, including breakfast, lunch, and dinner. Not only as a source of energy, but rice also has many socio-cultural functions in Indonesia (Nan 2016). Rice is a part of many kinds of traditional events and ceremonies in this country, such as for wedding party, funeral ceremony, as well as religious activities. Rice productivity needs to be improved in response to the increasing food demand due to rapid population growth. In Indonesia, the use of modern rice varieties that resulted in the Green Revolution required high inputs of chemical fertilizers and pesticides. These cultivars contributed to achieving the country’s target on rice productivity improvement, but the success story did not last for a long period. The Green Revolution changes in cropping systems have created various environmental and health-related problems including land degradation, soil and water pollution, Green House Gas emissions, and stimulate cancer disease, which also affects food safety (Carvalho 2006; Hoering 2011; Sharma and Shinghvi 2017). Alternatively, Organic Rice Systems have been promoted to solve those various environmental and health-related problems. However, the bulky organic fertilizers might not only have low nutrient quality but are also more laborious in transportation and application. Additionally, organic management may increase labor requirements for management of weeds and pests that can reduce rice yields and farmer income. Therefore, it is important to develop new practices and technologies that simultaneously favour rice production improvement, yield stability, and environmental conservation. Complex Rice Systems (CRS) is an integrated farming approach that aims to achieve these purposes by combining new technologies with traditional practices and knowledge. The main focus of CRS is to manage the agro-ecological processes in complex rice production systems by including fish, ducks and other components to promote high productivity while eliminating agrochemicals inputs (Khumairoh et al. 2012). There is a lot of evidence about the benefit of using this CRS in rice production systems. CRS are effective for natural suppression of pests, weeds and diseases (Jian et al. 2009; Khumairoh et al. 2012; Widyaningrum 2015; and Nan 2016), they support nutrient cycling (Khumairoh et al. 2012; Cheng-Fang 2009), contribute to farmer’s household nutrition and increase food diversity (Zona 2016), increase farmer’s income (Khumairoh et al. 2012; Andita et al. 2016) and contribute to food security in a changing climate (Khumairoh et al. 2012). However, the degree of complexity and the selected elements integrated into CRS may vary from place to place depending on the biophysical, social, economic, consumption patterns and cultural conditions. Hence, our experiment will investigate which elements are suitable to be integrated to improve rice production in Lima Puluh Kota, West Sumatra. In Lima Puluh Kota regency, rice is used as the main food and as the main income source for small-scale farmers. Rice production area in Lima Puluh Kota regency increased from 2011 (44,976 ha) to 2012 (46,660 ha). But, rice productivity in 2012 decreased about 2.37 percent compared to the previous year; the average production in 2012 was 4.75 Mg/ha (Pemkab Lima Puluh Kota 2015). Farms in Lima Puluh Kota regency are characterized by small farm area and limited capital. The green revolution package (high inputs of chemical fertilizers and pesticides) can trigger weed and pest outbreaks and may require more inputs for the plants to recover. This enhances the financial burden of smallholders and leads to harvest failures that can threaten food security in this area. Both conventional and organic rice systems are used in this region. Conventional rice systems are limited by the price of the artificial input and this system cannot maintain the rice productivity for a long period. In organic systems, not all the systems can achieve the same productivity as the conventional systems, especially in the early years after conversion to organic cultivation. Based on that, we evaluated the suitability of CSR for this region to find a better way to support food security of small-scale farmers.

Objective

The purpose of this experiment was to investigate how rice crop and whole farm productivity are affected by different combinations of ducks, fish, and field borders in Lima Puluh Kota regency.

Research Questions

1. Will additional elements such as ducks, fish, and border crops integrated into current rice systems in Lima Puluh Kota regency have a positive impact on rice development and productivity? 2. What is the effect of the additional elements on the presence of insects and weeds? 3. Can CRS improve the performance of current rice production systems in Lima Puluh Kota regency by reducing labor and external inputs and increasing productivity and income? Hypotheses

1. The additional elements such as ducks, fish, and border crop that were integrated into the rice systems can results in higher productivity and better financial results of organic rice systems of smallholder farmers in Lima Puluh Kota regency. 2. The application of Complex Rice Systems will reduce the abundance of pest insects and weeds in the current rice systems in Lima Puluh Kota regency. 3. The increasing complexity of the systems, the higher possibility to increase the current rice productivity in the Lima Puluh Kota regency.

2 Materials and Methods Experimental site Lima Puluh Kota is a regency in West Sumatra province in Indonesia. It is located between 0 degrees 25'28,71'' LU and 0 degrees 22'14,52'' LS and between 100 degrees 15'44,10"- 100 degrees 50'47,80'' BT with total area of 3.354,30 km2. Lima Puluh Kota Regency has a varied topography (flat, undulating, and hilly) with altitudes ranging between 110 m and 2,261 m above sea level. Agricultural land in this area is irrigated by 13 rivers of varying size (Pemkab Lima Puluh Kota 2015). This research was conducted at Mungka, Lima Puluh Kota Regency at an altitude of approximately 550 m above sea level and ran from July 2017 until December 2017. Rainfall data is available in Table S1.

Figure 1. Lima Puluh Kota regency, Source: google.com

Material The materials used in this experiment were rice (Oryza sativa) variety of Junjung, ducks (Anas platyrhynchos) variety of Mojosary with population 400 ducks/ha, fish (Oreochromis niloticus and Cyprinus carpio) with population 5000 fish/ha, sunn hemp (Crotalaria juncea) and long beans (Phaseolus vulgaris) (Figure 2).

Figure 2. The materials used in the experiments. a Local ducks (Anas platyrhynchos). b Nile fish (Oreochromis niloticus). c Long beans (Phaseolus vulgaris). d Sunn hemp (Crotalaria juncea)

Experimental Design The experimental design was a Randomized Complete Block Design with 6 treatments and 3 replication blocks (Figure 3). The treatments were: 1) conventional rice (CON) system; 2) organic rice (ORR) system; 3) organic rice with border crops (ORB); 4) organic rice with fish (ORF); 5) organic rice with ducks (ORD); and 6) the organic complex rice system with ducks, fish, and border crops (CRS).

Figure 3. Design layout of experiments. The box in the center of the plots: yield components observation; the box around the center of the plot: plant growth and development observations.

One experimental plot had an area of about 140 m2 (ranging approximately 12-16 m long and 9- 12 m wide). Every plot was surrounded by dikes to prevent water and nutrient flows between treated plots. The conventional system represented the commonly used systems in the Lima Puluh Kota regency. Chemical inputs such as chemical fertilizer and chemical pesticide are important parts of these systems, though the amount, frequency and type used will vary between farmers. In these experiments, 100 kg of nitrogen was split into two applications (50% on the day before rice transplanting and 50% 45 days after transplanting). The nitrogen came from a chemical fertilizer with the trade name Phonska containing nitrogen, phosphorus, and potassium (15% each) and urea (containing 46% nitrogen). Insecticide (imidacloprid) and the fungicides (mancozeb and carbendazim) were each applied three times to control pests and diseases. In the organic rice systems, chemical inputs were replaced by organic fertilizer. For these systems, the compost (as organic fertilizer) was used to fulfil the nutritional needs of plant (see Table S2 for compost composition). The amount of organic fertilizers applied to the organic rice plots was equivalent to the nitrogen amount applied in the conventional plots. In these experiments, the compost was applied two times (50% on seventh day before transplanting and 50% 45 days after transplanting). Additionally, two different preparations, extracts of garlic+ginger and a wood

5 ash+salt, were used to control pests and diseases in these systems. The wood ash+salt preparation was applied twice, at 28 days after transplanting (DAT) and 70 DAT. The extract of garlic+ginger was applied once at 49 DAT. The ORB system combined organic rice cultivation with additional border crops on the dikes such as sunn hemp and long beans. Sunn hemp and long beans can enrich the soil with symbiotically fixed atmospheric nitrogen, and, in this experiment, were also intended to attract natural enemies. The border plants were planted 15 days before rice transplanting. In ORF systems, a combination of nile fish (Oreochromis niloticus) and golden fish (Cyprinus carpio) was introduced to control pests and weeds. Ponds of 10 m x 1 m x 0.5 m in size were built inside the ORF plot to provide shelter for fish when the water level was low. In the ORD system, organic rice cultivation was combined with ducks that can have multiple functions in rice crops. While the duck activity can control weeds and pests and their manure could also increase the nitrogen available for the rice plants. A duck house was also built inside ORD plot. Finally, the most complex system (CRS) was integrated fish, ducks, and border crops in an organic rice system plot.

Figure 4. Land preparation.

Cultivation Methods Land clearing and construction of dikes were done to prepare the experimental plots for this experiment. Dikes were used to prevent nutrient flows and species movement from different treatments. Trenches were built to separate the blocks and to serve as water outlets. Water was piped in from similar sources via PVC pipes. Infrastructure such as fences, ponds, and duck houses were built on the treated plots. The System of Rice Intensification (SRI) was used as a cultivation method for all the systems. Based on SRI, single plants were transplanted to the rice field ten days after sowing. The ”Legowo 4:1” method was used to establish the planting arrangement for all systems. The Legowo method is a pattern of rice planting that leaves one row empty for every four rows planted (Bobihoe 2013; Figure 2), while the density in the outer rows is increased. This

6 results in a higher plant density of 185 600 per ha versus 160 000 per ha in conventional planting systems. This method can increase rice productivity per ha by between 12 and 22 percent (Haryanto et al. 2014). Observation and Sampling Plant Growth, Development, and Yield Growth and development of plants were measured destructively and non-destructively. Destructive measurements included plant biomass, and non-destructive observation included counting tiller numbers and plant height. Those measurements were performed at early tillering (28 DAT), maximum tillering (49 DAT), flowering (70 DAT), grain filling (84 DAT) and harvesting (105 DAT). A plant removed from the field for destructive measurement was replaced by another plant that was grown on an adjacent field of the experimental field. Replacing the removed plants prevented empty spaces that could increase heterogeneity of the environment. Sampling plant points are shown in Figure 3. At three points in each plot, two rice plants were removed. Before removal, plant height was measured and tillers were counted. Plants were washed to remove mud, especially at the root. Then leaves and panicles were separated from the straw. All the green leaves from one plant were measured to get the leaf area index (LAI). All of plants were then oven dried at 70ºC for 48 hours. They were weighed to get the dry matter. The Leaf Area Index (LAI) was calculated as follows: Leaf area per plant (cm2) LAI = Area available per plant (cm2)

And specific Leaf Area (SLA) was calculated as: Leaf area (cm2) SLA = Leaf dry weight (g)

The number of panicles and number of grains per panicle were counted, while and the 1000 grain weight was determined. Rice yields were measured from 6.25 m2 per plot, and then the yield as a proportion to the aboveground biomass was used to calculate the harvest index (HI). Moreover, nitrogen (N), phosphorus (P) and potassium (K) content in rice grains were analysed in the laboratory with a segmented-flow system. And then, the N, P and K uptake in rice grains were calculated. Pest and Weed Population Pests were recorded at 28, 49, 70 and 84 days after transplanting (DAT). Insect pests were collected using sweep nets between 6 a.m. to 8 a.m. Snails were counted in four sampling areas (each measuring 50 cm x 50 cm per plot). Weeds were collected two times, at 21 and 42 DAT on four square areas in each plot (each 50 cm x 50 cm). The weeds were washed, identified by species, and measured by density. Then, the weeds were dried oven at 70ºC for 48 hours to get the total dry matter per species.

7 Economic Farm Performance The economic farm performance was assessed from the input costs and harvested products. Input costs consisted of costs for fertilizers (kg), pesticides (kg), compost (kg), bio-pesticides (packet), plant seeds (kg), long bean seeds (kg), ducks, fish, duck foods (kg), fish foods (kg) and labour costs (hour). Revenues from harvested products from rice (kg), long beans (kg), fish (kg), and ducks (birds) were calculated based on production and prices. The gross margin per treatment was calculated as the difference between the revenues and the costs. Statistical Analyses The data on rice growth and development, pest population, farm production and gross margin were analysed using Microsoft Excel and the software SPSS. The normality of the data was analysed by the Shapiro-Wilk test. Square root and square root + 0.5 (Bartlett 1936; UC Davies Plant Sciences 2011) used to transform the data that not meet normality requirement. Data were analysed statistically using ANOVA. The contrasts between treatments were detected by F test, and if the resulting F count was larger than the F table value by 5%, followed by Duncan New Multiple Range Test (DNMRT) at the 5% significance level.

RESULTS Plant Growth, Development, and Yield Plant height increased until 70 DAT and stabilized thereafter (Figure 5). There was no effect of treatments on plant height in the early tillering period (28 DAT), the grain flowering period (70 DAT), or the grain filling period (84 DAT). In the maximum tillering period (49 DAT), the height of the plants in the ORR was the largest, but only the difference with the CON treatment was significant (Table S3).

Figure 5. Plant height (cm) of rice plants at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S3 for analysis of significance of differences.

8 The number of tillers per plant increased until the maximum tillering period (49 DAT), but declined during the generative phase (Figure 6). Significant differences between the treatments were observed at 49 DAT, and these differences increased until the final observation at 84 DAT (Table S4). At 84 DAT, the tiller number was largest for the treatments with ducks (ORD and CRS) and smallest for the CON treatment. LAI increased until 70 DAT and declined during the maturity phase, except the leaf area in ORR which declined after 49 DAT (Figure 7). The maximum LAI reached at 70 DAT was significantly higher for the treatments with ducks than for other treatments, and CON had the lowest LAI (Table S5). SLA declined and remained stagnant from the grain filling to the ripening period (Figure 7). At the final measurement of 84 DAT, the highest specific leaf areas were found in ORF, ORD, and CRS (Table S6).

Figure 6. Tiller number of rice plants at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS organic complex rice system with ducks, fish, and border crops. See Table S4 for analysis of significance of differences.

Figure 7. Leaf area index and specific leaf area of rice plant at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; ; CRS, organic complex rice system with ducks, fish, and border crops. See Tables S5 and S6 for analysis of significance of differences.

Total plant dry matter (above and below ground) was significantly affected by the treatments in all growth and development stages (Figure 8). The lowest total dry matter was found in the CON system. The dry matter of plants in ORD and CRS was remarkably high at 70 DAT to harvesting (105 DAT) (Table S7). The dry matter increased throughout the plant growth and development.

Figure 8. Dry matter of rice plant at 28, 49, 70, 84, and 105 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S7 for analysis of significance of differences.

The rice yields and the yield component variables were significantly influenced by the treatment: the highest yields were obtained by the plants in ORD and CRS, while the lowest was found in CON treatment (Table 1). The same effect occurred in 1000 grain weight measurements in all

10 treatments, except CON treatment. The highest yield was in CRS and ORD (6.2 Mg/ha), which is approximately 40% higher than the average rice yield in Lima Puluh Kota regency.

Panicle Number Grains/Panicle 1000 Grain Yield Harvest Index Treatment Weight (g) (Mg/ha) CON 11.4±0.35a 108±2.35a 18±0.27a 3.5±0.20a 0.22±0.02a ORR 13.1±0.21b 122±2.10b 20±1.04b 4.5±0.16b 0.27±0.01ab ORB 13.5±0.41b 127±6.84b 21±0.98b 4.6±0.44b 0.26±0.02ab ORF 14.5±0.68b 139±2.97c 21±0.73b 5.1±0.16b 0.28±0.01b ORD 16.3±0.48c 145±0.41c 22±0.61b 6.2±0.30c 0.28±0.01ab CRS 16.7±0.24c 145±0.94c 22±0.83b 6.2±0.19c 0.27±0.01ab

Figure 9. Dry matter above and below ground of rice plant at generative phase. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S8 for analysis of significance of differences.

Figure 10. N, P, and K uptake of rice grain at generative phase. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S9 for analysis of significance of differences.

Figure 9 shows that dry matter above and below ground in the end of the experiment was affected by the treatments. The lowest above ground dry matter was found in CON treatment, but the lowest below ground dry matter measurements were found in ORR and ORB (Table S8). Plants in ORD and CRS not only produced better above ground dry matter but also had the highest below ground dry matter. This study also observed nitrogen, phosphorus, and potassium uptake of rice grain (Figure 10). The highest nitrogen uptake was in the treatment ORF, ORD, and CRS. The CRS treatments resulted in the highest phosphorus and potassium uptakes (Table S9). The composition of nitrogen, phosphorus, and potassium on the rice grain are available in Table S9.

Pest and Weeds Population Pest Population Stem borers, leafhoppers, flies, rice bugs, and snails were dominant pests observed in this experiment. Leafhoppers were differentiated into green leafhoppers and other leafhoppers. The green leafhopper is an important pest that is harmful to rice plants, because it is a vector for the tungro bacilliform virus. Other leafhoppers found were white leafhoppers and orange leafhoppers, which are less harmful to rice plants (Shepard et al. 1995). Stem borers, green leafhoppers, flies, and rice bugs showed the same pattern in abundance at each of the four sampling times (Figure 11). The patterns showed increasing abundance starting from 28 DAT to 49 DAT, followed by a decline until 84 DAT. The highest abundance was at 49 DAT. The abundance of stem borer in this treatment did not differ significantly at 28 DAT, 49 DAT, and 84 DAT. Its abundance is only significantly differ at 70 DAT (Table S10). At 70 DAT, stem borers were found only in CON, ORR, ORB and ORF treatments but not in CRS and ORD.

12 The abundance of green leafhoppers only significantly differs at 49 DAT from other sampling periods (Table S11). At 49 DAT, the abundance of green leafhoppers in CRS, ORF, and ORD was the lowest compared with the other treatments. Treatment ORR had a higher abundance of green leafhoppers at that times. The abundance of other leafhoppers was higher compared with the other pest. The highest abundance of other leafhoppers was at 28 DAT, but declined afterward. The lowest abundance was found in CRS, ORB, and ORD at the last measurement (84 DAT) (Table S12). This experiment showed that the flies abundance was high at 28 DAT, 49 DAT, and 70 DAT. The abundance of flies only significantly differed at 49 DAT, 70 DAT, and 84 DAT (Table S13). In general, the fly abundance was lower in CRS and ORD treatments than other treatments. The treatments have influenced the rice bugs abundance significantly at 28 DAT, 49 DAT, and 70 DAT, but the difference was not significant in the last measurement (Table S14). Rice bugs were significantly higher at 49 DAT in the CON and ORR treatments, but at 28 DAT and 70 DAT, rice bugs were only dominant in the conventional treatment. Finally, this study demonstrated that the abundance of snails increased from 28 DAT until 70 DAT, and after that it decreased at 84 DAT in the CON, ORR, ORB, and ORF treatments. Snail abundance was significantly different at each observation time (Table S15). No snails were found in the CRS treatment after 28 DAT or in the ORD treatment after 49 DAT. Treatments CON, ORB, and ORF resulted in the highest snail abundance at the final observation.

Figure 11. a) Stem borer abundance, b) Green leaf hoppers abundance, c) Other leaf hoppers abundance, d) Flies abundance, e) Rice bugs abundance, and f) Snail abundance at 28, 49, 70, and 84 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Tables S10, S11, S12, S13, S14, and S15 for analysis of significance of differences.

Weed Population There were 14 weed species found in this experiment in two sampling times. However, not all weed species were found at each time of sampling. Only 12 weed species were found at 21 DAT and also in sampling times at 42 DAT. In general, CON treatments produced the largest weed biomass and density at both sampling dates (Figure 12; Tables S16 and S17). At 21 DAT, a treatment which used plant borders, fish, and ducks – either separately or in combination – is more effective in weed suppression, compared with the other treatments. However, at 42 DAT, a treatment that included ducks with the rice plants was superior in weed suppression, compared with the other treatments. It can be seen in Figure 12, the CRS and ORD treatments resulted in the lowest dry matter of weeds.

Figure 12. Dry matter and abundance of the weeds at 3 and 6 weeks after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks CRS, organic complex rice system with ducks, fish, and border crops. See Tables S18 and S19 for analysis of significance of differences.

Knotgrass (Paspalum distichum L.) and oval-leaf pondweed (Monocaria vaginalis) were only found at 21 DAT (Tables S19 and S20). Goat weed (Agerantum conyzoides) and saltmarsh bulrush (Bolboschoenus conyzoides) were only found at 42 DAT. The rest of weed species can be found at 21 DAT and 42 DAT (Tables S18, 19, 20, and 21). Globe fringe rush (Fimbristylis dichotoma L.) and purple nutsedge (Cyperus rotundus L.) were the dominant species that were found at 21 DAT (Tables S19 and 20). Some weeds were found in all treatment plots, and some others were only found in some treatments plots. For example, globe fringe rush, purple nutsedge, false daily (Eclipta prostate L.), jungle rice (Echinochloa colona L.), seedbox (Ludwigia hyssopifolia), and smallflower umbrella sedge (Cyperus difformis L.) can be found in all treatment plots. Rice flat sedge (Cyperus iria L.), southern cutgrass (Leersia hexandra Sw), goosegrass (Eleusine indica L.), water lettuce (Pistia stratiotes), knotgrass, and oval-leafed pondweed can only be found in some treatments.

In 42 DAT, globe fringe rush and jungle rice were the species of weeds that dominated in dry matter and were abundant in rice field treatments (Tables S20 and S21). Only four weed species that can be found in all treatments, i.e. globe fringe rush, purple nutsedge, jungle rice, and seedbox. The other species such as false daisy, smallflowers umbrella sedge, rice flat sedge, southern cutgrass, goosegrass, water lettuce, goat weed, and saltmarsh bulrush can only be found in some treatments. Treatment ORB in this observation resulted in the lowest number of weed species at 42 DAT. However, the lowest dry matters can be found in CRS and ORD treatments. Economic farm performance Besides producing rice, the treatments of ORB, ORF, ORD, and CRS also produced long beans, fish and ducks. Thus, these marketable products were included in the economic calculations as part of the farm revenue. The experimental treatments have significantly influenced the cost, revenue, and gross margin of the farm. The increasing complexity of the systems increased the cost, revenue, and gross margin of the farm. While the CON treatment was lower in farm cost, the CRS treatment was higher in farm cost. However, the more complex systems (CRS) resulted in higher farm revenue and farm gross margin. As the only rice grain could be harvested, the gross margin in CON and ORR were the lowest. Meanwhile, as the most complex treatment consisted of rice, border plants, fish and ducks, the CRS treatment had a better farm gross margin but was not significantly different from ORD systems. Following CRS and ORD, the treatments ORF and ORB had better farm gross margin than CON and ORR (Figure 14; Table S23).

Figure 13. . a) Farm cost, Farm revenue, and Farm gross margin (in millions of rupiah) from each system. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops. See Table S23 for analysis of significance of differences.

Discussion The growth and development of plants are influenced by several factors, including genetics, environment and management, and interactions between these factors (Boyer 1982; Hatfield and Walthall 2015). This experiment used the same variety of rice plants but applied different treatments. Adding border plants, fish, and ducks probably can affect the environmental conditions. So, management factors and their interactions with environmental and genetic factors play an important role in this research. Those factors affected various growth and development of rice plants, including tiller numbers, leaf area index, specific leaf area, and dry matter. However, on rice plant height, the effects of genetics were more dominant than the other factors (Fageria 2007). The experiment conducted by Khumairoh (2011) and Andita et al. (2016) resulted in the same height of rice plants in different management. The use of border plants, fish, and ducks in rice plants are the factors that produce the different management and environmental condition in this study. The result showed that ducks play an important role in rice plant systems. The behaviour of ducks can suppress two major problems in rice production. The first major problem is the competition of the main plant with the growth of weeds. The existence of weeds in rice fields can inhibit plant growth and development, and reduce plant productivity due to competition for light, water, and nutrients. Experiments of Namuco et al. (2009) resulted in a decrease of grain yields of upland rice of up to 60% because of the competition between rice and weeds. The treatments incorporating organic rice with border plants, fish, and ducks (separately or in combination) showed better results in weeds suppression, compared with organic rice systems and conventional systems. The border crops such as long beans and sunn hemps can shade the weeds and resulted in inhibiting the germination of photophilic weed species (Nan 2016). Fish can eat the small seeds, soft plant fragments, rhizomes, or stolon and their behaviour reduced the growth of weeds (Frei and Becker 2005; Nan 2016). The movement of ducks around the rice fields and their tendency to feed on the small seed of weeds resulted in weed suppression (Liu 1998; Men et al. 2008; Khumairoh et al. 2012; Widyaningrum 2015; and Nan 2016). However, in overall, ducks more effective in weeds suppression than other integrations. The weeds needed to be removed from the rice fields before beginning to compete with the rice plants. Competition for nutrients and water in the early growth of plants will affect further growth and development. The level of competition will reduce as the plant grows and develops. Bigger and taller plants will prevent the weeds from getting to sources of light, thus decreasing the competition level. Treatment CON had the highest dry matter of weeds and the highest abundance compared to five other treatment in the third week and the sixth week after transplanting. The total dry matter of weeds in the conventional systems are 20.7 g/m2 and 89.9 g/m2 at 21 DAT and 42 DAT, respectively. The use of chemical fertilizers in rice fields was probably the reason for the higher dry matter and abundance of weeds in the conventional systems. Chemical fertilizer triggers the growth of the weeds, because the nitrogen in chemical fertilizer can be directly absorbed by the weeds. The success story of ducks in weed suppression has been seen in previous experiments. Experiments by Men et al. (2008) in Vietnam showed that using ducks for weed suppression was more efficient than using herbicides. In Japan, introducing ducks in paddy fields suppressed the emergence of weeds (Liu 1998). Other experiments in Indonesia also showed the function of ducks to suppress growth weed in a rice field (Khumairoh et al. 2012; Widyaningrum 2015; and Nan 2016). Integration of rice plants and ducks in farming systems is also known as sustainable agriculture movement in Asia (Suh 2014). The second major problem is the negative impact pests on plant growth and development. Crop failure might occur if the pest population is above the economic threshold. The presence of pests in rice fields disrupts the growth and development of rice plants and ultimately reduces the yield. Damage caused by pest attacks varies depending on the type of pest, population, plant maturity, the presence of natural enemies, and environmental conditions (Shepard et al. 1995). For example, green leafhoppers result in more severe damage than white leafhoppers due to the virulence factors of green leafhoppers. The use of chemical pesticides to control pests in rice field was as effective as the use of organic pesticides in this experiment. Pest abundance in the conventional treatment was almost the same as with the other treatments. However, adding ducks in rice fields reduces the pest population, according to Teo et al. (2001) and Liang et al. (2014). Complex rice systems and integrating organic rice with ducks had the lowest abundance of pests. For example, the abundance of snails in both treatments with ducks (ORD and CRS) was less than the other treatments. Based on observation, the CRS and ORD treatments resulted in the lowest population of pests. The inclusion of ducks in rice fields in both systems indicates their effectiveness in pest suppression. At the first observation, the abundance of some pest was not significantly different in the rice fields with or without ducks. But after that, the effectiveness of ducks in pest suppression increased over time. This was due to the increasing activity of the ducks in the rice fields as compared to their early activity. Many experiments resulted in pest suppression after the introduction of ducks in rice fields. Zhang et al. (2005) found that pest suppression by the inclusion of ducks in the rice fields was higher than in other treatments and conventional treatments. This result is supported by the work of Nan (2016), a low density of ducks (100 ducks/ha) in rice fields suppressed pests to a similar level as pesticide applications, while higher density (800 ducks/ha) led to even further reductions of pests. Other experiments have also shown that using ducks in rice fields is more effective for pest suppression than the conventional systems (Yang et al. 2004; Frei and Becker 2005; Widyaningrum 2015). The other potential benefit of incorporating ducks into a rice field is the increased availability of nutrients and oxygen. The excreted manure produced continuously from the ducks increases the availability of nutrients for the rice plants (Khumairoh 2011), part of these nutrients are recycled and part is imported as feed. Also, the excreted manure of ducks can be used to feed the fish

19 and increase the nutrient availability for long beans and sunn hemps. The activity of the ducks can increase the amount of oxygen that is available for the plant (Khumairoh 2011; Nan 2016). These two benefits can provide the better rice plant growth and development. Due to many factors that are mentioned above, the treatments which including ducks in rice fields (CRS and ORD) resulted in the better growth, development, and yield components of rice plants than in the other treatments. It can be shown from observations of plant tiller, leaf area index, relative growth rate, total dry matter, relative growth rate, panicle number, grains/panicle, harvest index, and yield. In some observations of the plants (overall) and at various growth stages, the CRS and ORD treatments showed growth similar to the other treatments in the first observation. However, at the end of the growth and development periods, these two treatments were superior compared to the other treatments. The yield of the plants is connected with plant growth and development. Better plant growth and development resulted in higher yields. Plant growth and development contribute to determining the yields. For example, a faster leaf area expansion can increase the plant growth, a higher number of tillers could increase the number of panicles, etc. Significantly, the number of tillers was also related to the grain yield in all growth periods, especially at the initial periods of panicle growth (Fageria 2007). The previous experiments also showed higher productivity in when ducks were included in the rice fields. In Bangladesh, adding ducks to rice fields can increase grain yields by 20%, compared with traditional systems (Hossain et al. 2005). In China, raising the ducks in rice fields produced 1.9 times higher grain yields, compared with non-duck treatments in organic systems (Teng et al. 2016). The existence of ducks also resulted in higher grain yields compare with non-duck treatments in Indonesia (Khumairoh et al. 2012). The experimental treatments produced different main products from each system. While CRS produced various main products, CON and ORR only produced a single main product. Besides producing rice grains, CRS also produced long bean grains, fish, and ducks. The other systems such as ORB, ORF, and ORD produced additional main products depending on the integrated systems. The increasing complexity of the systems also increased the costs, revenues and gross margins of the systems. While the CRS required higher costs, CON and ORR required less costs. In labour costs, CRS were slightly higher than CON and ORR because of the additional costs for the management of long beans, fish, and ducks. However, the labour costs for pest and weed managements in CRS were lower than CON and ORR. CON and ORR, which only produced rice grain, resulted in lower revenue compared to other treatments. Therefore, CRS with its complexity, produced greater revenue due to many products produced from this system. For gross margin calculation in these experiments, ORD and CRS produced higher gross margin than other systems. Though ORD and CRS had greater costs, these two systems produced more revenue than the other systems. In rice grain yields, these two systems produced more than the other experiments. Also, the higher price of the ducks helped these two systems to get more

20 revenue. The benefit from the duck sales and the higher yields of grain produced led to higher gross margin in ORD and CRS. The results in this experiment were also supported by previous experiments. Khumairoh et al (2012) showed higher gross margin in complex rice systems that involved ducks, fish, and azolla compared to rice and compost treatments. In these experiments, Khumairoh et al. (2012) showed twice the return on investment in CRS than in the rice system with compost treatments. The treatments which including ducks in rice fields (CRS and ORD) resulted in better plant performances and yields, weed and pest suppression, and higher gross margin than the other treatments. It is concluded that ducks have a significant role to increase the current rice productivity in the Lima Puluh Kota regency.

Conclusion and Recommendation

The increased complexity of the systems of rice cultivation affect the growth, development, and yield of rice plants. CRS showed the best growth, development, and yields compared to CON, ORR, ORB, and ORF. However, this result is similar to the ORD treatment results. This condition happened due to the inclusion of ducks in the rice fields. The activity and behaviour of the ducks lead to the better growth and development of rice plants, resulting in better yields. The treatment of CRS and ORD showed effectiveness in pest and weed suppression. Many treatment systems were tested in these experiments: rice-border plants, rice-fish, rice-ducks, and rice-border plants-fish-ducks to investigate suppression of pests and weeds. The result showed that the existence of border plants, fish, and ducks had an effect in reducing pest and weeds compared to control systems. However, the best pest and weed suppression was found in ORD and CRS. The presence of border plants and fish can reduce the pest and weed population, but they were not as effective compared to the existence ducks in the rice fields. Economically, the increasing of complexity of the systems increased the costs for that system. However, this investment resulted in a considerably higher revenue from the more complex systems. In the end, CRS produced the higher gross margin than other treatments except the ORD treatments. The higher rice productivity and the sales of ducks supported the ORD treatments to reach the same gross margin as the CRS treatments. All in all, the integration of organic rice with ducks or in complex systems is recommended in rice farming systems in Lima Puluh Kota regions. This recommendation is due to the better performance of growth, development, and yields of rice plants and the better pest and weed suppression in ORD and CRS treatments. Also, the increase of the gross margin from these two systems supports this recommendation.

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Supplementary Material

Table S 1. Rainfall Data in Guguak Sub District (mm) Augustus September October November Month July 2017 2017 2017 2017 2017 Amount (mm) 104 190 293 190 257 Source: Climatology Station Padang Pariaman

Table S 2. Composition of Compost (%) pH N C-Org C/N ratio P2O availability K-dd (cmol(+)kg-1 (%) (%) (ppm) 7.24 1.26 25.36 20.12 564.92 14.74

Table S 3. Data of Plant Height (cm) Treatment Plant Height 28 DAT 49 DAT 70 DAT 84 DAT CON 47.8±2.42 a 70.1±6.61 a 106.5±1.25 a 111.2±1.78 a ORR 50.7±2.95 a 86.5±6.89 b 115.9±1.26 a 119.0±3.02 a ORB 46.3±0.65 a 81.4±4.79 ab 111.2±5.26 a 111.4±7.64 a ORF 47.1±2.53 a 78.3±6.16 ab 110.2±9.24 a 114.5±5.67 a ORD 44.4±1.04 a 78.3±5.81 ab 114.2±9.98 a 117.9±9.78 a CRS 49.9±2.51 a 83.1±7.04 ab 115.8±7.64 a 119.5±9.28 a

Table S 4. Data of Tiller Number (per plant) Treatment Tiller Number 28 DAT 49 DAT 70 DAT 84 DAT CON 15.2±2.68 a 20.9±4.84 a 19.9±1.57 a 15.3±0.15 a ORR 18.2±2.36 a 26.4±5.82 ab 20.2±1.88 a 18.1±0.82 b ORB 18.8±1.50 a 26.7±4.50 abc 23.7±3.00 b 18.8±0.62 b ORF 21.8±5.25 a 31.2±2.92 bc 24.6±1.70 b 20.5±1.06 c ORD 14.8±0.67 a 33.1±1.64 bc 25.5±0.54 bc 22.8±1.03 d CRS 20.1±4.18 a 35.6±5.82 c 28.3±1.98 c 23.4±0.34 d

Table S 5. Data of Leaf Area Index (cm2 cm-2) Treatment Leaf Area Index 28 DAT 49 DAT 70 DAT 84 DAT CON 0.82±0.17 a 2.30±0.94 a 2.51±0.24 a 2.08±0.33 a ORR 1.08±0.26 a 3.31±1.00 b 3.01±0.13 ab 2.73±0.29 ab ORB 1.02±0.16 a 2.64±0.78 ab 2.90±0.59 a 2.58±0.48 ab ORF 1.02±0.28 a 2.73±0.63 ab 3.13±0.67 abc 2.70±0.26 ab ORD 0.66±0.05 a 2.98±0.52 ab 3.99±0.68 bc 3.18±0.44 b CRS 1.07±0.18 a 3.40±0.80 b 4.12±0.17 c 3.02±0.23 b

Table S 6. Data of Specific Leaf Area (cm2 g-1) Treatment Specific Leaf Area 28 DAT 49 DAT 70 DAT 84 DAT CON 329.6±10.83 b 216.0±18.17 a 172.0±2.02 b 176.9±2.62 b ORR 295.3±13.62 ab 195.1±3.82 a 169.3±2.17 b 172.8±1.42 ab ORB 316.5±31.95 b 191.7±10.21 a 168.8±0.64 b 173.0±1.92 ab ORF 262.8±6.98 a 199.6±3.94 a 162.7±0.53 a 169.3±2.77 a ORD 294.7±12.89 ab 200.6±20.34 a 161.5±3.76 a 170.3±1.07 a CRS 269.2±20.77 a 194.6±7.06 a 159.2±1.26 a 168.8±0.16 a

Table S 7. Data of Total Dry Matter (Above and below Ground) of Rice Plant (g/plant) Treatment Total Dry Matter 28 DAT 49 DAT 70 DAT 84 DAT 105 DAT CON 4.73±0.82 a 25.1±6.63 a 42.03±3.23 a 55.80±2.78 a 86.53±2.22 a ORR 7.07±1.44 ab 41.83±10.41 55.40±3.17 b 68.77±2.56 b 91.13±3.17 ab b ORB 9.20±1.99 ab 31.9±3.46 ab 59.57±3.48 b 68.93±3.41 b 95.17±1.21 bc ORF 10.73±2.66 b 33.13±3.85 62.40±4.48 b 70.67±5.11 b 99.90±2.02 c ab ORD 5.70±0.24 ab 35.47±5.00 79.40±7.62 c 79.57±5.71 c 122.33±4.29 d ab CRS 1.80±1.06 ab 37.60±6.52 b 78.50±4.16 c 82.50±2.38 c 121.57±4.12 d

Table S 8. Total Dry Matter Above-Ground and Below-Ground (g/plant) Treatment Dry Matter Above-Ground Dry Matter Below-Ground CON 74.93±2.94 a 11.60±1.40 a ORR 81.03±4.68 ab 10.10±1.59 a ORB 84.27±2.63 b 10.87±2.07 a ORF 85.60±3.86 b 14.27±2.29 ab ORD 104.27±2.50 c 18.06±1.82 b CRS 103.73±3.24 c 17.87±3.18 b

Table S 9. N, P, and K composition (%) and N, P, and K uptake (kg/ha) on rice grain Treatment Composition Uptake N (%) P (%) K (%) N (kg/ha) P (kg/ha) K (kg/ha) CON 1.90±0.20 0.48±0.03 0.35±0.04 66.5±3.66 16.8±1.27 12.4±1.26 ab a a a a a ORR 1.84±0.12 0.52±0.03 0.40±0.03 84.2±5.67 23.7±2.10 18.3±1.69 ab a ab ab ab ab ORB 1.91±0.19 0.48±0.02 0.39±0.01 86.2±12.50 21.6±1.29 17.4±1.50 ab a a ab ab ab ORF 2.11±0.07 0.49±0.02 0.42±0.02 108.2±5.75 25.3±1.61 21.7±1.52 b a ab b abc bc ORD 1.60±0.19 0.44±0.05 0.41±0.02 98.7±14.69 27.3±3.96 25.4±2.29 a a ab b bc cd CRS 1.74±0.05 0.53±0.05 0.47±0.04 107.1±5.75 32.5±3.40 29.0±3.38 ab a a b c d

Table S 10. Stem Borer (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 3.0±3.00 a 4.0±1.53 a 2.0±1.00 c 0.0 a ORR 0.7±0.33 a 7.0±3.21 a 1.3±0.33 bc 0.3±0.33 a ORB 0.3±0.33 a 3.3±1.45 a 1.0±0.58 abc 0.0 a ORF 0.3±0.33 a 2.0±0.58 a 0.3±0.33 abc 0.0 a ORD 0.0 a 3.0±2.52 a 0.0 a 0.0 a CRS 0.7±0.67 a 1.0±0.58 a 0.0 a 0.0 a

25 Table S 11. Green Leafhopper (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 3.0±1.15 a 3.0±0.58 ab 1.3±1.33 a 1.0±1.00 a ORR 1.7±0.67 a 4.3±0.33 b 0.0 a 0.0 a ORB 0.7±0.67 a 2.7±0.33 ab 2.0±1.00 a 1.0±0.58 a ORF 0.3±0.33 a 2.0±0.58 a 1.0±0.58 a 1.0±0.58 a ORD 1.7±1.67 a 1.7±0.33 a 1.0±0.00 a 1.3±0.33 a CRS 0.3±0.33 a 2.0±0.00 a 0.3±0.33 a 2.0±1.00 a

Table S 12. Other Leaf Hopper (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 70.0±14.64 b 20.0±4.04 ab 5.0±1.73 ab 2.0±0.58 ab ORR 56.0±15.52 b 26.3±8.37 b 4.7±1.33 ab 2.3±0.67 b ORB 67.0±20.50 b 19.3±3.18 ab 5.0±2.52 ab 0.3±0.33 a ORF 74.0±17.00 b 24.0±4.51 ab 9.7±2.85 b 2.7±0.88 b ORD 26.7±7.80 a 14.0±1.53 ab 3.3±1.86 a 0.3±0.33 a CRS 19.3±6.57 a 9.7±0.88 a 2.7±0.33 a 0.3±0.33 a

Table S 13. Flies (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 32.7±14.88 a 23.3±3.76 ab 27.0±3.06 c 9.0±1.00 c ORR 10.7±5.61 a 38.3±7.22 b 14.0±1.15 ab 6.7±1.45 bc ORB 30.7±16.91 a 29.0±8.14 ab 12.0±3.00 ab 6.7±2.33 bc ORF 14.7±6.17 a 26.7±7.13 ab 19.0±7.57 bc 8.7±0.88 c ORD 7.7±3.18 a 18.7±7.17 a 8.3±3.06 a 4.7±1.33 b CRS 3.3±0.88 a 11.3±2.40 a 8.0±2.03 a 2.0±0.58 a

Table S 14. Rice Bugs (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 4.7±1.67 b 8.7±4.26 b 3.3±0.33 b 4.3±0.33 a ORR 0.7±0.67 a 9.3±2.96 b 0.3±0.33 a 2.3±1.20 a ORB 0.7±0.33 a 5.7±2.60 ab 0.0 a 2.0±0.58 a ORF 0.0 a 2.3±0.33 ab 0.3±0.33 a 2.7±0.67 a ORD 0.0 a 0.3±0.33 a 1.0±1.00 a 3.0±1.15 a CRS 0.3±0.33 a 1.3±1.33 a 0.3±0.33 a 2.3±1.20 a

Table S 15. Snails (per plot) Treatment Stem Borer 28 DAT 49 DAT 70 DAT 84 DAT CON 11.7±1.86 b 26.7±0.88 ab 57.3±6.69 c 16.3±1.20 c ORR 14.3±2.73 bc 17.3±2.40 a 22.0±4.58 ab 12.0±1.15 b ORB 25.3±5.24 cd 26.0±7.81 ab 32.0±4.51 b 14.7±0.33 b ORF 32.7±7.88 d 53.0±18.01 b 62.3±17.85 c 16.7±0.88 b ORD 0.3±0.33 a 0.0 a 0.0 a 0.0 a CRS 0.0 a 0.0 a 0.0 a 0.0 a

Table S 16. Dry Matter Total of Weed (g/m2) Treatment Dry Matter Total of Weeds 21 DAT 42 DAT CON 20.7±3.59 b 89.9±21.17 c ORR 14.5±1.77 ab 50.6±20.60 b ORB 8.9±0.67 a 15.7±3.31 ab ORF 7.9±1.24 a 32.1±8.44 ab ORD 9.9±1.85 a 8.7±4.44 a CRS 8.1±2.39 a 6.6±2.06 a

Table S 17. Abundance Total of Weeds Treatment Dry Matter Total of Weeds 21 DAT 42 DAT CON 506±108.97 c 432±187.78b ORR 316±75.57 bc 149±44.08 a ORB 69±22.00 a 27±3.51 a ORF 126±40.08 ab 83±18.41 a ORD 160±70.26 ab 28±12.55 a CRS 123±21.59 ab 15±1.15 a

Table S 18. Dry matter of weed species at 21 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops Weeds Species Treatments CON ORR ORB ORF ORD CRS Globe fringe rush 6.3±2.57 b 2±1.18 ab 1.5±0.45 a 3.5±0.56 ab 2.2±0.96 ab 1.5±0.18 a (Fimbristylis miliacea L.) Purple nutsedge (Cyperus 5.9±2.95 a 2±1.18 a 0.9±0.27 a 3.5±0.56 a 4±1.87 a 3.2±1.59 a rotundus L.) False daisy (Eclipta 2.1±0.62 b 0.7±0.27 a 0.1±0.03 a 0.3±0.25 a 0.4±0.44 a 0.2±0.10 a prostrata L.) Jungle rice (Echinochloa 0.5±0.30 a 0.6±0.33 a 3.5±1.87 a 1.3±0.63 a 2.3±1.71 a 2.1±1.51 a colona L.) Seedbox 1.38±0.52 b 0.02±0.02 b 0.37±0.19 ab 0.53±0.33 ab 0.36±0.26 ab 0.97±0.44 ab (Ludwigia hyssopifolia) Smallflower umbrella sedge 1.3±0.59 a 0.7±0.11 a 1.3±1.16 a 0.4±0.24 a 1.7±1.25 a 0.5±0.27 a (Cyperus difformis L.) Rice flat sedge (Cyperus 2.1±1.11 b 1.7±0.38 b 0 a 0.3±0.22 ab 0.2±0.17 ab 0.6±0.36 ab iria L.) Southern cutgrass (Leersia 3.5±1.76 a 2.9±1.70 a 1.0±1.01 a 0.2±0.22 a 0.2±0.11 a 0 a hexandra Sw.) Goosegrass (Eleusine 0.72±0.42 b 0.17±0.17 ab 0.03±0.03 ab 0 a 0.08±0.08 ab 0.18±0.14 ab indica L.) Water lettuce (Pistia 0 a 0 a 0.03±0.03 a 0 a 0.08±0.00 a 0 a stratiotes) Knotgrass (Paspalum 0.5±0.52 a 0.8±0.76 a 0 a 0.4±0.24 a 0.9±0.90 a 0.2±0.21 a distichum L.) Oval-leafed pondweed 0 a 0.02±0.02 a 0 a 0.01±0.01 a 0.02±0.02 a 0 a (Monochoria vaginalis)

27 Table S 19. Weed species’ abundance at 21 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops Weeds Species Treatments CON ORR ORB ORF ORD CRS Globe fringe rush 186.3±64.72 85.7±49.65 22.3±6.49 a 55.3±12.25 a 52.7±24.69 a 53.7±18.78 a (Fimbristylis miliacea L.) b ab

Purple nutsedge 159.3±84.50 85.7±49.65 14.7±5.17 a 55.3±12.25 a 78±38.57 a 90±22.85 a (Cyperus rotundus L.) a a False daisy (Eclipta 93±41.04 b 47.3±19.94 4±1.15 a 16.3±13.38 a 13±13.00 a 14±8.50 a prostrata L.) ab Jungle rice (Echinochloa 3±2.52 a 3±1.53 a 7±2.08 a 3.7±1.20 a 4.7±2.40 a 6±1.00 a colona L.) Seedbox 32.7±15.07 0.7±0.67 a 3±1.53 a 6.7±2.33 a 5±3.61 a 7.3±0.88 a (Ludwigia hyssopifolia) b Smallflower umbrella 55.3±30.55 41.3±6.36 a 15.7±15.17 a 18±15.00 a 51±41.51 a 14.3±3.28 a sedge a (Cyperus difformis L.) Rice flat sedge (Cyperus 49.7±29.17 31.7±24.77 0 a 9.3±7.42 ab 1±1.00 ab 8.7±5.55 ab iria L.) b ab Southern cutgrass 19.7±10.33 33.3±18.27 8±8.00 ab 3.3±2.40 ab 2.7±1.45 ab 0 a (Leersia hexandra Sw.) ab b Goosegrass (Eleusine 8±4.16 a 2.7±2.67 a 0.3±0.33 a 0 a 4±4.00 a 1±0.58 a indica L.) Water lettuce (Pistia 0 a 0 a 0.3±0.33 a 0 a 1±1.00 a 0 a stratiotes) Knotgrass (Paspalum 20.7±20.67 7.3±7.33 a 0 a 3.3±2.03 a 4.3±4.33 a 2±2.00 a distichum L.) a Oval-leafed pondweed 0 a 0.7±0.67 a 0 a 0.3±0.33 a 0.7±0.67 a 0 a (Monochoria vaginalis)

Table S 20. Dry matter of weeds species at 42 day after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops Weeds Species Treatments CON ORR ORB ORF ORD CRS Globe fringe rush 15.2±4.97 18.5±2.46 7.8±1.08 ab 7.2±1.57 ab 3.4±1.72 a 3.4±0.84 a (Fimbristylis miliacea L.) bc c

Purple nutsedge 9.2±3.82 c 2.1±1.16 1.7±1.23 ab 5.2±2.33 bc 1.3±1.27 a 1.4±1.33 a (Cyperus rotundus L.) ab False daisy (Eclipta 8.16±4.67 b 0.80±0.55 0 a 0.50±0.50 a 0.74±0.74 a 0.03±0.03 a prostrata L.) a Jungle rice (Echinochloa 36.6±19.13 19.1±16.66 4.4±4.39 a 8.8±4.50 ab 0.9±0.47 a 0.4±0.34 a colona L.) b ab Seedbox 6.9±1.85 c 6.1±3.87 1.8±1.83 ab 3.4±2.33 abc 1.1±0.41 ab 0.3±0.20 a (Ludwigia hyssopifolia) bc Smallflower umbrella 6.0±3.02 a 1.5±0.79 a 0 a 5.3±4.74 a 0 a 0 a sedge (Cyperus difformis L.) Rice flat sedge (Cyperus 1.7±1.71 a 0 a 0 a 0 a 0 a 0 a iria L.) Southern cutgrass 4.2±2.20 b 2.7±2.66 0 a 0.2±0.25 ab 0 a 0 a (Leersia hexandra Sw.) ab Goosegrass (Eleusine 0 a 0.63±0.39 0 a 0.05±0.05 ab 0 a 0.26±0.26 indica L.) b ab Water lettuce (Pistia 0.2±0.20 a 0.04±0.04 0 a 0 a 0 a 0 a stratiotes) a Goat weed 0 a 0.61±0.31 0 a 0 a 0.05±0.05 a 0 a (Ageratum conyzoides) b Saltmarsh bulrush 1.9±1.66 a 1.2±0.73 a 0 a 0.7±0.73 a 1.0±1.04 a 0.5±0.48 a (Bolboschoenus maritimus)

28 Table S 21. Weed species abundance at 42 days after transplanting. CON, conventional rice system; ORR, organic rice system; ORB, organic rice with border crops; ORF, organic rice with fish; ORD, organic rice with ducks; CRS, organic complex rice system with ducks, fish, and border crops Weeds Species Treatments CON ORR ORB ORF ORD CRS Globe fringe rush 115.7±38.75 c 67.7±14.89 bc 20±7.09 a 34±15.89 ab 10±6.11 a 9.3±0.33 a (Fimbristylis miliacea L.) Purple nutsedge 16±8.00 b 7±6.03 ab 1.7±1.20 a 6.3±2.67 ab 1±1.00 a 1.3±0.88 a (Cyperus rotundus L.) False daisy 180.3±93.30 b 21±16.26 a 0 a 2.7±2.67 a 10.3±10.33 a 1±1.00 a (Eclipta prostrata L.) Jungle rice 32.7±22.17 b 15±12.53 ab 4±4.00 a 7±1.53 ab 1±0.58 a 1±0.58 a (Echinochloa colona L.) Seedbox 18.3±7.45 bc 21.7±8.67 c 1.3±1.33 a 11.3±7.97 abc 2±1.00 ab 0.7±0.33 a (Ludwigia hyssopifolia) Smallflower 27±22.65 a 11.7±7.62 a 0 a 7.7±3.93 a 0 a 0 a umbrella sedge (Cyperus difformis L.) Rice flat sedge 9.3±9.33 a 0 a 0 a 0 a 0 a 0 a (Cyperus iria L.) Southern 19.3±9.74 b 5.3±5.33 ab 0 a 0.3±0.33 a 0 a 0 a cutgrass (Leersia hexandra Sw.) Goosegrass 0 a 2±1.15 b 0 a 0.3±0.33 ab 0 a 0.3±0.33 ab (Eleusine indica L.) Water lettuce 2.3±2.33 a 2.3±2.33 a 0 a 0 a 0 a 0 a (Pistia stratiotes) Goat weed 0 a 1±0.58 b 0 a 0 a 0.3±0.33 ab 0 a (Ageratum conyzoides) Saltmarsh 11.3±8.09 a 3.3±2.40 a 0 a 5.3±5.33 a 2.7±2.67 a 1.3±1.33 a bulrush (Bolboschoenus maritimus)

Table S 22. Weight of Ducks (kg/ha), Fish (kg/ha), and Long Beans (Mg/ha) ORB ORF ORD CRS Long Beans 5.1±0.39 - - 6.6±0.14 Nile Fish - 282±38.43 - 332±19.70 Golden Fish - 119±8.93 - 126±7.50 Ducks - - 472±43.29 523±41.31

Table S 23. Cost, Revenue, and Gross Margin of the farm (million rupiah) Treatment Cost (million rupiah) Revenue (million Gross Margin (million rupiah) rupiah) CON 12.3±0.18 a 19.2±1.19 a 6.9±1.17 a ORR 18.0±0.13 b 25.2±0.82 b 7.2±0.95 a ORB 20.2±0.07 c 28.3±2.30 b 8.1±2.24 ab ORF 22.9±0.00 d 35.4±1.22 c 12.4±1.22 b ORD 37.6±0.29 e 59.3±1.58 d 21.6±1.36 c CRS 45.3±0.13 f 71.2±1.59 e 25.8±1.70 c

29 Table S 24. Distribution of Cost, Revenue, and Gross Margin of the farm (million rupiah) Treatment Cost (million rupiah) Revenue (million rupiah) Gross Margin (million rupiah) Rice Long Duck Fish Rice Long Duck Fish Rice Long Duck Fish bean bean bean CON 12.3 0.0 0.0 0.0 19.2 0.0 0.0 0.0 6.9 0.0 0.0 0.0 ORR 18 0.0 0.0 0.0 25.2 0.0 0.0 0.0 7.2 0.0 0.0 0.0 ORB 17.9 2.3 0.0 0.0 24.9 3.4 0.0 0.0 7.0 1.1 0.0 0.0 ORF 17.7 0.0 0.0 5.2 28.2 0.0 0.0 7.2 10.5 0.0 0.0 2.0 ORD 17.4 0.0 20.2 0.0 34.1 0.0 25.2 0.0 16.7 0.0 5.0 0.0 CRS 17.3 2.3 20.2 5.2 33.9 4.4 25.2 7.8 16.3 2.1 5.0 2.5

Table S 25. N Soil Analysis (%) Treatment Before Treatment After Treatment CON 0.176 0.249±0.01 bc ORR 0.270±0.01 c ORB 0.224±0.01 ab ORF 0.207±0.01 a ORD 0.271±0.01 c CRS 0.246±0.02 abc