A Substantial Component in Sustainable Organic Agriculture

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Udhaya Nandhini and SomasundaramAvailable Ind. online J. Pure at App.www.ijpab.com Biosci. (2020 ) 8(2), 133-143 ISSN: 2582 – 2845

DOI: http://dx.doi.org/10.18782/2582-2845.8007 ISSN: 2582 – 2845 Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 Review Article

Intercropping – A Substantial Component in Sustainable Organic Agriculture

D. Udhaya Nandhini1* and E. Somasundaram2 1Post Doctoral Fellow, Centre of Excellence in sustaining Soil Health, Anbil Dharmalingam Agricultural College & Research Institute, Trichy-620 027 Tamil Nadu 2Professor and Head, Department of Sustainable Organic Agriculture, Tamil Nadu Agricultural University, Coimbatore-641 003, Tamil Nadu, India *Corresponding Author E-mail: [email protected] Received: 3.03.2020 | Revised: 7.04.2020 | Accepted: 11.04.2020

ABSTRACT st The greatest challenge of the 21 century in many developing countries are to produce more and more basic necessities namely food, fodder, fuel and fibre for ever increasing human and animal population from the limited available land. The availability of land for agriculture is shrinking every day as it is increasingly utilized for non-agricultural purposes. Under this situation, one of the important strategies to increase agricultural output is development of high intensity cropping systems including intercropping system which involves biotic and abiotic stress resistant, soil building, protein rich and oil producing crops. Intercropping is a ways to increase diversity in an agricultural ecosystem. This review summarizes the most important aspects of intercropping system in organic agriculture.

Keywords: Intercropping, Stress resistant, Agricultural ecosystem, Diversity

INTRODUCTION agricultural systems following objectives such Sustainable agriculture is a type of agriculture as: ecological balance, more utilization of that is more efficient in use of resources, for resources, increasing the quantity and quality the benefit of human, and is in balance with and reduce yield damage to pests, diseases and the environment. In other words, sustainable weeds. Restoring on-farm biodiversity through agriculture must be ecologically appropriate, diversified farming systems that mimic nature economically justified and socially desirable. is considered to be a key strategy for One of the key strategies in sustainable sustainable agriculture. On-farm biodiversity, agriculture is restoration diversity to if correctly assembled in time and space, can agricultural ecosystems, and its effective lead to agro-ecosystems capable of management. Intercropping is a ways to maintaining their own soil fertility, regulating increase diversity in an agricultural ecosystem. natural protection against pests, and sustaining Intercropping as an example of sustainable productivity.

Cite this article: Udhaya Nandhini, D., & Somasundaram, E. (2020). Intercropping – A Substantial Component in Sustainable Organic Agriculture, Ind. J. Pure App. Biosci. 8(2), 133-143. doi:

http://dx.doi.org/10.18782/2582-2845.8007

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 Intercropping is an age old practice of growing & Choubey, 1991). Best utilization of simultaneously two or more crops on the same nutrients, moisture, space and solar energy can field such that the period of overlap is long be derived through mixed/intercropping enough to include vegetative stage (Gomez & system. Gomez, 1983). Intercropping has been a Sarkar et al. (1995) reported that regular practice followed by the farmers of intercropping not only stabilizes crop India, Africa, Sri Lanka and Malaysia. production by reducing the impact of weather Intercropping is mainly practiced to cover the vagaries, but also increases cropping intensity risk of failure of one of the component crops considerably. due to vagaries of weather or pest and disease An enormous variety of intercropping incidence. Yield advantages in intercropping systems exists, reflecting the range of crops system are mainly because of differential use and management practices farmers throughout of growth resources by component crops. The the world use to meet their requirements for complementarity will occur when the growth food, fiber, medicine, fuel, building materials, patterns of component crops differ in time. forage, and cash. Intercropping systems may Intercropping of legumes in involve mixtures of annual crops with other association with non-legumes helps in annuals, annuals with perennials, or perennials utilization of nitrogen being fixed by legumes growing together and coexisting for a time in the current growing season, but also helps in (figure 1). residual build up of nutrients in soil (Sharma

Fig. 1: Depending on the degree of both the spatial and temporal dimension of two (or more) crop species

Intercropping input, risk reducing under dry farming Growing two or more crops simultaneously on situations for crop diversification and ful the same field; crop intensification is in both fillment of subsistence objectives. At higher temporal and spatial dimensions; there is input levels it will be able to necessary to re intercrop competition during all or part o crop evaluate and recombine various activities. growth. Intercropping systems tend to be low Eg. Groundnut + Redgram + Castor

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 Cotton + Black gram/green gram where capital can be one ofthe major Sorghum + Redgram constraints in agricultural production, Types of intercropping microclimate modifications that require high Mixed Intercropping inputs such as theuse of synthetic shade Growing two or more crops simultaneously materials are not feasible (Jaya et al., 2001). with no distinct row arrangement. Also Microclimate modification by cheap and referred to as mixed cropping. The seeds of the simple means, such as intercropping might be crop varieties are mixed in desired proposition, acceptable as well as affordable. Maize is one sown and incorporated. of the row crops often selected for Eg. Grass legume mixture; Mixing the intercropping to provide shelter to understory seeds of sorghum and cowpea in 5:1 ratio and crops because of its wide adaptation over a broad casted. rangeof climates. Row Intercropping Insurance against crop failure Growing two or more crops simultaneously One important reason for which intercropping where one or more crops are planted in rows; is popular in the developing world is that it is often referred to as intercropping. more stable than monocropping. The stability Eg. Sorghum in paired rows under intercropping can be attributed to the intercropped with one row of cowpea partial restoration of diversity that is lost under Planting 1 row of red gram for monocropping. For farmers who have limited every 10 rows of groundnut sources, income and stability yield of Strip Intercropping agricultural systems is very important. From Growing two or more crops simultaneously in this point of view, intercropping provides high different strips wide enough to permit insurance against crop failure, especially in independent cultivation but narrow enough for areas subject to extreme weather conditions the crops to interact agronomically. Normally such as frost, drought, flood, and overall followed in sloppy lands and in soils prone for provides greater financial stability for farmers, erosion. making the system particularly suitable for Eg. Wheat and Bengal gram in labor-intensive small farms. When several alternate strips of 5-10 m crops can be grown together, fail to produce a Relay Cropping product, could be compensated by other crop, Growing two or more crops simultaneously and thereby reduces the risk. Risk of during the part of the life cycle of each. A agronomy failure in multi cropping systems is second crop is planted after the first crop has lower than pure cropping systems. It may be reached its reproductive stage of growth but an appropriate growth condition for a species before it is ready for harvest. and inappropriate for other species (Eskandari Eg. Broad casting black gram or green et al., 2009). gram in the standing rice crop about 7-10 days Increasing production before its harvest. One of the main reasons for the use of Advantages of intercropping in sustainable intercropping around the world is produced organic agriculture more than a pure cropping of same land Modification of microclimate amount (Caballero & Goicoechea, 1995). Intercropping practice could modify the Ghanbari and Lee (2002) reported that dry microclimate by reducing light intensity, air matter production in wheat and beans temperature, desiccating wind and other intercrops had been more than their pure climatic components. The emphasis of much cropping. Odhiambo & Ariga, (2001) with previous work on intercropping temperate maize and beans intercrops in different ratios crops in the tropics was mainly on soil found that production increased due to reduced microclimate characterization and not on competition between species compared within-canopy microclimate. In the tropics, competition within species. Wiley (1990) Copyright © March-April, 2020; IJPAB 135

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 considers intercropping as an economic decrease dry bulk density and soil resistance to method for higher production with lower root penetration (Latif et al., 1992). Studies levels of external inputs. This increasing use conducted by Carof (2006) revealed the role of efficiency is important, especially for small- a living cover crop root in maintaining soil scale farmers and also in areas where growing structure and hydraulic conductivity over time. season is short (Altieri, 1995). Production This author suggested that it can even provide more in intercropping can be attributed to the long-term benefits. Even if explicit data on soil higher growth rate, reduction of weeds, water content in cereal/legume intercropping is reducing the pests and diseases and more extremely rare, studies conducted by Celette et effective use of resources due to differences in al. (2008) on intercropped vineyards showed resource consumption (Eskandari, 2012). In that the soil water profile could be improved addition, if there are "complementary effects" by reduced run-off and enhanced soil between the components of intercropping, infiltration. The same results are assumed production increases due to reducing the under cereal/legume intercropping. competition between them (Mahapatra, 2011). Soil moisture Udhaya Nandhini and Latha (2014) reported Water use efficiency is also another that pigeonpea + greengram intercropping with importance of intercropping system. different row ratios were found to increase the Integration of legume either in sole or in the production. Pigeonpea + greengram with 1:3 intercropping systems hasthe potentiality to row proportion gives 29% higher economic extract more moisture from deeper soilsurface. advantage over pure stands due to high Intercropping with legumes is an excellent resource use efficicney (Udhaya Nandhini & practice for controlling soil erosion and Latha, 2015). sustaining crop production. Sorghum-cowpea Soil structure intercropping reduced runoff by 20-30% Increased belowground biomass and root compared with sorghum sole crop and by 45- activity have a major impact on soil properties 55% compared with cowpea monoculture. and on the soil solution. In maize/legume Moreover, soil loss was reduced with intercropping experiments, increased root intercropping by more than 50% compared activity has been shown to have positive with sorghum and cowpea monocultures. effects on soil aggregation and to significantly

Fig. 2: Live mulch for moisture conservation

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 Soil erosion control attributable to subsequent disease infections Plant cover in intercropping plays an important and mechanical damage, whereas loss of plant role in stopping energy from rainfall and height reduces efficiency of light interception. prevent runoff which could cause soil erosion. Intercropping can provide better lodging Kariaga (2004) showed that in maize-cowpea resistance for some crops highly susceptible to cropping system, cowpea acts as a good cover lodging. The introduction of legumes and decreases run off than maize-bean system. intercropped with non-legumes has drawn Rana and Rana (2011) found that taller crops considerable interest because not only is there act as wind barrier for short crops, in the ability to improve cash returns by intercrops of taller cereals with short legume increasing land use efficiency, but the crops. However, sorghum+cowpea cropping inclusion of component crops such as canola system decreases erosion by 20-30% than or mustard as an intercrop will also greatly sorghum mono crop by 45-55% compared to improve lodging resistance of grain legumes, cowpea monocrop. However, Kinama et al. thereby increasing yield, product quality, and (2007), Kinama et al. (2011) found that, harvest efficiency. intercropping maize senna and senna-cowpea Soil fertility reduced soil erosion compared to Conservation of soil fertility in intercropping monocropped plots. Chen et al. (2010) is a form of rotation that each season is done observed that intercropping of wheat and on land. Cereal– grain legume intercropping potato grown in strips up to 5m can reduce has potential to address the soil nutrient wind erosion, soil desertification and depletion on smallholder farms. The legumes degradation effectively. Deep roots penetrate play an important role in nitrogen fixation far into the soil breaking up hardpans and use (Peoples and Craswell, 1992), and are moisture and nutrients from deeper down in important source of nutrition for both humans the soil. Shallow roots bind the soil at the and livestock. Rhizobium bacteria are able to surface and thereby help to reduce erosion and have a symbiotic relationship with plants of help to aerate the soil. leguminosae family and thereby can fixation Canopy and relative humidity of atmospheric nitrogen into available nitrogen Intercropping composed of different patterns for plants uptake and the result nitrogen (as an of canopy development and different essential element for soil fertility and plant maturation times can display a greater amount growth) is added to the soil. There are several of leaf area over the course of the growing reports indicating that increasing the nitrogen season and intercept more total light energy content in non-legume plants, due to the than monocultures. Where polycultures intercrops of these plants with plants of produce earlier or later canopy, evaporation of leguminosae family (Eskandari et al., 2009).In soil moisture is reduced, weeds suffer from addition, the green parts and roots of the light and moisture competition, and there is legume component can decompose and release decreased rain impact erosion through canopy nitrogen into the soil where it may be made filtering and greater root structures. Wilson available to subsequent crops. In particular, and Ludlow (1991) reported soil temperatures under low soil N conditions the advantages of up to 10oC cooler on forage under tree legumes in an intercrop are greater (Lunnan, plantations in the tropics, assisting seedling 1989). The benefits of a legume intercrop with survival, soil-water relations and possibly respect to nitrogen are direct transfer of affecting the rate of litter breakdown and nitrogen from the legume to the cereal during nitrogen mineralization. the current intercrop and residual effects when Lodging resistance to prone crops the fixed nitrogen becomes available on the Lodging, which is commonly observed in sequential crops after the senescence of the some crops, frequently can reduce plant legume and the decomposition of residues. growth severely. Some of the damage is often The direct transfer of nitrogen to companion Copyright © March-April, 2020; IJPAB 137

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 crops occurs mainly by excretion of nitrogen greater interception of solar radiation, higher from the legume nodules, representing an light use efficiency or a combination of the immediate source of nitrogen to the cereal. two (Willey,1990).When total crop densities Thus, the use of legumes in mixtures are higher in intercrops, they can intercept contributes some nitrogen to the cereal more light especially early in the growing component and some residual nitrogen to the season. Intercrops composed of non- following crops. After the intercrop is synchronous patterns of canopy development harvested, decaying roots and fallen leaves and different maturation times can display a provide nitrogen and other nutrients for the greater amount of leaf area over the course of next crop (Lithourgidis et al., 2011). This the growing season and intercept more total residual effect of the pulse crop on the next light energy than monocultures. crop is largest when the remains of the pulse Biru Amedie Yimam (2002) reported are left on the field and ploughed after harvest that higher light transmission ratio was (Rahman et al., 2009). observed in sole sorghum as compared to Legume Effect sorghum intercropped with legumes. The beneficial effects of the legumes in any Significantly lower light transmission was crop rotation and intensive cropping system is noticed in sorghum + groundnut system. termed as legume effect. N fixed by the Mohan (2003) reported that the performance intercrop of legume may be available to the of cropping system was enhanced when maize associated cereal in the current growing season and legumes were intercropped as compared to or as a residual N for the benefit of a their sole performance in study. Maize succeeding cereal crop. Inclusion of legumes intercropped with legumes in 1:2 row in the cropping systems is beneficial in many proportion was superior in utilizing natural ways: resources like light and moisture content. 1. Legumes fix atmospheric nitrogen in root Patil (2003) reported that the LTR and nodules and thus improve the nitrogen light interception differed significantly due to status of the soil. cropping system but not due to row 2. It saves up to 25% of recommended level proportions of little millet and pigeonpea. of nitrogen application to the associated Significantly higher LTR and light cereals when grown as intercrop. interception values were recorded with sole 3. The crop residues and root nodules of pigeonpea in recommended spacing of 60 x 30 legumes release nitrogen during cm (40.18 and 59.82 per cent, respectively) decomposition for the use of the and sole pigeonpea with 90 x 20 cm geometry succeeding crop. (42.06 and 57.94 per cent, respectively) over 4. Legumes absorb soil phosphorus more sole little millet, little millet + relay horse efficiently and part of this mobilized gram and intercropped treatments mean. phosphorus in organic form is available to Sarika Jena et al. (2010) declared that the the succeeding crop. It means legumes interception of PAR in sesame canopy was covert inorganic phosphorus into organic maximum in 4:1 row ratio of sesame + form of phosphorus and thus is able to greengram intercropping. Utilisation of light extract insoluble forms of soil phosphorus. use efficiency was highest in pigenopea + 5. Many of legumes can tolerate some greengram with 1:3 proportion (Udhaya amount of shading and drought. Nandhini & Latha, 2015). Light interception/Light transmission ratio Pest control Light interception and light use efficiency are Compared with monoculture, adding more powerful concepts for characterizing the plant species to a cropping system can affect resource capture and use efficiency of herbivores in two ways. Firstly, the cropping systems, including intercrops. environment of the host plants, e.g. Improved productivity can result from either neighbouring plants and microclimatic Copyright © March-April, 2020; IJPAB 138

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 conditions, is altered and secondly, the host cotton (Rabindra, 1985) and Lablab bean in plant quality, e.g. morphology and chemical sorghum reduced the sorghum stem borer content, is altered (Langer et al., 2007). incidence. Intercropping upland rice with Habitat diversification makes the agricultural groundnut at low and medium populations of environment unfavourable for growth, groundnut resulted in lower green stink bug multiplication and establishment of insect pest (Nezara viridula) and stem borer (Chilo populations. The following are some zacconius) infestations in rice compared with approaches by which the pest population can rice monoculture. This demonstrates that be brought down. Intercropping or trap careful selection of crop combination and plant cropping system has been found favourable in population could lead to reduced pest reducing the population and damage caused by incidence in upland rice. Also, intercropping many insect pests due to one or more of the cowpea with cotton proved the best in following reasons. suppressing the population of thrips and  Pest outbreak less in mixed stands due whiteflies, produced high yield, and was at par to crop diversity than in sole stands with the intercrops of cotton with marigold  Availability of alternate prey and cotton with sorghum. Hence it is highly  Decreased colonization and important that appropriate intercropping reproduction in pests systems have to be evolved where reduction in  Chemical repellency, masking, pest level occurs. feeding inhibition by odours from Weed control non-host plants. Traditionally intercrops have been practiced to  Act as physical barrier to plants. smother the weeds which depends manily on  Trap crops attract insects and prevent crop behaviour and weed growth. Liebman the pests from reaching the target crop and Dyck (1993) indicated that weed concentrating them in a particular area population density and biomass production where they can be economically may be markedly reduced using intercropping destroyed (spatial diversification). Intercrops may Hence it is highly important that demonstrate weed control advantages over appropriate inter/trap cropping systems have to sole crops in two ways. First, greater crop be evolved where reduction in pest level yield and less weed growth may be achieved if occurs. Sustainable systems of agricultural intercrops are more effective than sole crops in production are seen in areas where suitable usurping resources from weeds or by crop rotation i.e. proper mixtures of crops and suppressing weed growth through alleopathy. varieties are adopted in a given agro- Alternatively, intercrops may provide yield ecosystem. For example growing rice after advantages without suppressing weed growth groundnut in garden land in puddled condition if intercrops use resources that are not eliminates white grub. exploitable by weeds or convert resources to Intercropping systems with greater harvestable material more efficiently than sole diversity have the potential to reduce crop crops (Geno & Geno, 2001). pests and increase the diversity of pollinators Lawson et al. (2006) reported that in and natural enemies of crop pests. maize-legume intercropping system, legume Intercropping maize in cotton fields increased crops are generally suppressed by weeds and the population of Araneae, coccinellidae and shade effect of corresponding maize crop Chrysopidae by 62.8-115.7% compared with which cause difference in photosynthetic control fields. Maize also acted as a trap crop efficiency of the two intercropped crops. for H. armigera reducing the second Intercropping also encourages efficient generation eggs and damage to cotton (Wu et utilization of the environmental resources al., 1991). Intercropping pulses in cotton (Egbe & Adeyemo, 2007); thus, the growths of reduced the population of leaf hopper on weeds are decreased, depending on the Copyright © March-April, 2020; IJPAB 139

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 availability of environmental resources. Maize parasite infections (Fenandez et al., 2007) + legume intercropping is advocated because which ultimately may improve the soil of the control of weeds and legume root fertility, crop yield and farmer’s income.

Fig. 3: Calapogonium intercropping for weed control

Promotion of biodiversity land resources and farming inputs including Intercropping is one way of introducing more labour etc., Intercropping allows effective biodiversity into agro-ecosystems and results utilization of growth resources through crop from intercropping studies indicate that intensification both in space and time increased crop diversity may increase the dimensions. The conventional ways of number of ecosystem services provided. intensifying crop production are vertical and Higher species richness may be associated horizontal expansions. Intercropping offers with nutrient cycling characteristics that often two additional dimensions, time and space. can regulate soil fertility. Intercropping of Space dimension compatible plants promotes biodiversity by The canopies of component crops may occupy providing a habitat for a variety of insects and different vertical layers with taller component soil organisms that would not be present in a tolerant to strong light and high evaporative single crop environment. Stable natural demand and the shorter component favouring systems are typically diverse, containing shade and high relative humidity Multi-storied numerous different kinds of plant species, cropping in coconut and planting shade trees arthropods, mammals, birds, and in cocoa and tea plantations use this principle. microorganisms. As a result, in stable systems, Similarly, root systems of component crops serious pest outbreaks are rare because natural may exploit the nutrients in different layers of pest control can automatically bring soil and hence utilize the resources in a better populations back into balance (Altieri, 1995). way with much less competition. Therefore, on-farm biodiversity can lead to Time dimension agro ecosystems capable of maintaining their When component crops of widely varying own soil fertility. duration are planted, their peak demand for Resource use efficiency light and nutrients are likely to occur at The main aim of intercropping is to augment different periods, thus reducing competition. the total productivity per unit area and time, In a combination having early and late besides judicious and equitable utilization of maturing crops (sorghum + red gram), when

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 early maturing crops are harvested, conditions and oat sown varing seeding ratiosand become favourable for the late maturing crop seeding rates of vetch. Field Crops (red gram) to put forth its full vigour. Research, 41, 135-140. Thus, selection of crops that differ in Carof, M. (2006). Fonctionnement de competitive ability in time or space is essential peuplements en semis direct associant for an efficient intercropping system as well as du blé tendre d'hiver (Triticum decisions on when to plant, at what density, aestivum L.) à différentes plantes de and in what arrangement. Although in this way couverture en climat tempéré. cropping management decisions specify the domain_other. INAPG design of intercropping systems, intercrop (AgroParisTech), Français. performance is governed largely by the Celette, F., Gaudin, R., & Gary, C. (2008). availability of and the competition for the Spatial and temporal changes to the environmental resources. water regime of a Mediterranean Other complementary effects vineyard due to the adoption of cover In an intercropping system involving a legume cropping. European Journal of and a non-legume, part of the N fixed in the Agronomy, 29(4), 153-162 root nodule of the legume may become Chen, Z., Cui, H., Wu, P., Zhao, Y., & Sun Y., available to the non-legume component. With (2010). Study on optimal the presence of rhizosphere microflora and intercropping width to control wind mycorrhiza, one species may lead to erosion in North China. Soil Till. Res. mobilization and greater availability of 110, 230-235. nutrients not only to the species concerned but Egbe, O.M., & Adeyemo, M.O., (2007). also to the associated species. Provision of Estimation of the effect of physical support by one species to the intercropped pigeon pea on the yield intercropped climbing species may improve and yield components of maize in the yield of the climber. Examples are coconut southern Guinea Savannah of Nigeria. + pepper and maize + beans. The taller African Journal of Agricultural component acts as wind barrier protecting the Research, 2(12), 667-677. shorter components from lodging. Eskandari, H., Ghanbari, A., & Javanmard, A., (2009). Intercropping of cereals and CONCLUSION legumes for forage production. From this review point of view it is very Notulae Scientia Biologicae.1, 7-13. important to include intercropping systems Eskandari, H., (2012). Yield and quality of with appropriate agronomic practices such as forage produced in intercropping of timely irrigation, pest protection and the likes maize (Zea mays) with cowpea(Vigna to sustain the organic system. sinensis) and mungbean (Vigna radiate) as double cropped. Journal of REFERENCES Basic and Applied Scientific Research. Altieri, M. A. (1995). Agroecology: the 2, 93-97. science of sustainable agriculture, Fenandez, M., Josefina, C., & Sillero, D.R., second edition. Publisher: Westview (2007). Intercropping with cereals Press. reduces infection by Biru Amedie Yimam. (2002). Intercropping of Orobanchecrenata in legumes. grain legumes in sorghum (Sorghum Journal of Crop Protection. 26, 1166- bicolor). M. Sc. (Agri.) Thesis, 1172. University of Agricultural Sciences, Geno, L., & Geno, B., (2001). Polyculture Dharwad. Production: Principle, benefits and Caballero, R., & Goicoechea, E.L. (1995). risk of multiple cropping. A reportfor Forage yield quality of common vetch the Rural Industry Research and Copyright © March-April, 2020; IJPAB 141

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 Development Corporation (RIRDC), of legumes on soil physical quality in Publication, No. 01134. a maize crop. Plant soil. 140, 15-23. Ghanbari, A., & Lee, H.C., (2002). Lawson, Y.D.I., Dzomeku, I.K., Asempa, R., Intercropped field beans (Vicia faba) & Benson, S., (2006). Weed control in and wheat (Triticum aestivum) for maize using Mucuna and Canavalia as whole crop forage: effect of nitrogen intercrops in the Northern Guinea on forage yield and quality. The Savanna zone of Ghana. Journal of Journal of Agricultural Science. 138, Agronomy. 5, 621-625. 311-314. Liebman, M., & Dyck, E., (1993). Crop Gomez, A.A., & Gomez, K.A., (1983). rotation and intercropping strategies Multiple Cropping in the Humid for weed management. Ecological Tropics of Asia, IDRC Ottawa, Applications. 3(1), 92-122. Canada, p. 248 (Palaniappan P and Lithourgidis, A.S., Vasilakoglou, I.B., Dhima, SivaramanK. Ed.). In: Cropping K.V., Dordas, C.A., & Yiakoulaki, Systems in the Tropics- Principles and M.D., (2011). Annual intercrops: an Management 2nd Edition. New Age alternative pathway for sustainable International (P) Ltd. Publishers, New agriculture. Review article. AJCS. Delhi. 5(4), 396-410 Jaya, I.K.D., Bell, C.J., & Sale, P.W., (2001). Mahapatra, S.C., (2011). Study of grass- Modification of within- microclimate legume intercropping system in terms in maize for intercroppingin the of competition indices and lowland tropics. In: Proceedings of the monetaryadvantage index under acid Australian Agronomy lateritic soil of India. American Conference.AustraliaSociety of Journal of Experimental Agriculture. Agronomy, Australia. p123-133. 1(1), 1-6. Kariaga, B.M., (2004). Intercropping Maize Mohan, H.M., (2003). Maize based With Cowpeas and Beans for Soil and intercropping studies with grain Water Management in Western legumes in Vertisols. M. Sc. (Agri.) Kenya. In: ISCO 213th International Thesis, University of Agricultural Soil Conservation Organisation Sciences, Dharwad. Conference, Brisbane, Conserving Odhiambo, G.D., & Ariga, ES., (2001). Effect 993, 1-5. of intercropping maize and beans on Kinama, J.M., Ong, C.K., Stigter, C.J., & Ng, striga incidence and grain yield. In: J.K., (2011). Hedgerow Intercropping Seventh Eastern and Southern Africa Maize or Cowpea/Senna for Drymatter Regional Maize Conference. 183-186. Production in Semi-Arid Eastern Patil, N.B., (2003). Studies on intercropping of Kenya. Journal of Agricultural little millet with pigeonpea on Alfisols Science and Technology, 1, 372-384. of Dharwad. M. Sc. (Agri.) Thesis. Kinama, J.M., Stigter, C.J., Ong, C.K., & Ng, Univ. Agric. Sci., Dharwad, J.K., (2007). Arid Land Research and Karnataka, India. Management Contour Hedgerows and Peoples, M.B., & Craswell, E.T., (1992). Grass Strips in Erosion and Runoff Biological nitrogenfixation: Control on Sloping Land in Semi-Arid Investments, Expectations and Kenya Contour Hedgerows and Grass ActualContributions to Agriculture. Strips in Erosion and Runoff Control Plant Soil. 141, 13-39 on Sloping Land in Semi-Arid Kenya Rabindra, R.J., (1985). Transfer of Plant 21, 1-19. Protection Technology in Dry crops. Latif, M.A., Mehuys, G.R., Mackenzie, A.F., In: Integrated Pest and Disease Alli, I., & Faris, M.A., (1992). Effects Management (Ed) S. Jayaraj. Proc. Copyright © March-April, 2020; IJPAB 142

Udhaya Nandhini and Somasundaram Ind. J. Pure App. Biosci. (2020) 8(2), 133-143 ISSN: 2582 – 2845 Natl. Seminar, Tamil Nadu intercropping under different cropping Agricultural University, Coimbatore. geometries. Agriculture for 337-383. Sustainable Development. 2(2), 169- Rahman, M.M., Amano, T., & Shiraiwa, T., 171. (2009). Nitrogen use efficiency and Udhaya Nandhini, D., & Latha, K.R., (2015). recovery from N fertilizer under rice Analysis of light transmission ratio based cropping systems. Aust J. Crop and yield advantages of medium Sci., 3, 336-351. duration pigeonpea in relation to Rana, S.S., & Rana, M.C., (2011). Cropping intercrop and different plant System. Book 1-92. population. African Journal of Sarika Jena, N., Rajib, D., Mazumdar, P., Agricultural Research, 10(8), 731- Bandyopadhyay, & Chakraborty, P.K.. 736. (2010). Pattern of Absorption and Willey, R.W., (1990). Resource use in Interception of Photosynthetically intercropping systems. Journal of Active Radiation in Sesamum- Agriculture and Water Management Greengram Intercropping System. 17, 215-231. Research Journal of Agronomy. 4, 1-9. Wilson, J.R., & Ludlow, MM., (1991). The Sarkar, R.K., & Shit Dand Chakraborthy, A., environment and potential growth of (1995). Yield and economics of herbage under plantations. pp.10-24. pigeonpea based intercropping system In: H. M. Shelton and W. W. Stur on rainfed upland of Chotanagpur (eds.). Forages for Plantation Crops, plateau. Indian Journal of Agronomy. Proceedings No. 32, June 1990, 40, 30-34. Australian Centre for International Sharma, R.S., & Choubey, S.D., (1991). Effect Agricultural Research, Bali. of maize legume intercropping Wu, G., Chen, Z., Dong, M.S., Ji, L.H., & Shi. systems on nitrogen economy and J., (1991). Influence of interplanting nutrient status of soil. Indian Journal corn in cotton fields on natural enemy of Agronomy. 36, 60-63. population and its effect on pest Udhaya Nandhini, D., & Latha, K.R., (2014). control in Southern Shaanxi, Chinese Yield and biological potential indices Journal of Bio Control 73, 101-104. of cajanuscajan + vignaradiata