January 2006

ADAPTING CROP VARIETIES TO ENVIRONMENTS AND CLIENTS THROUGH DECENTRALIZED - PARTICIPATORY APPROACH

M.T.K.Gunasekare 1

ABSTRACT

Since 1990s, participatory approaches have became a driving force for agricultural research and rural development. The participatory approach in crop improvement involves the client-farmer in the selection or breeding and highly appropriate for increasing food security and improving livelihoods of subsistence farmers in developing countries. This has developed over the past decades as an alternative and complementary breeding approach to formal to effectively address the needs of the farmers, especially in marginal or resource poor areas. In pursuit of this concept, this paper discusses the trends, advantages and challenges in this approach highlighting the contemporary evidence of success case studies commissioned by various authorities worldwide. While successful experiences are evident, the potential of such applications are still to be explored. Among the key challenges to the approach, this article pays attentions especially to technical, economic and institutional challenges that need to be overcome to integrate end-users based participatory approaches into the formal plant breeding systems. The paper concludes by describing synergies that can potentially be achieved by linking centralized and decentralized plant breeding models over biotechnological methods.

Key words : Formal plant breeding, Participatory plant breeding, Participatory Vareital Selection, marginal environments, decentralized testing, modern varieties

INTRODUCTION south Asia and sub-Saharan Africa (Pinstrup-Andersen et al., 1999). The Crop improvement plays an important necessary increase in agricultural role in the development and production represents a huge challenge strengthening of local agricultural to the local farming systems and must systems. The Green Revolution based come mainly from increased yield per on introduction of improved varieties unit area, given the limited scope for with high yield potential, together with expanding cultivated land worldwide. technological packages (inorganic fertilizer, pesticides, irrigation etc.) The present approach to agricultural have greatly contributed to the increase research and development however, is in agricultural production in several to improve crop, and produce food of regions worldwide. quality for all, while reducing environmental degradation and United Nations projections estimate depletion of natural resources base and that the world population will continue conserving agricultural diversity. In to grow from the current 6 billion to addition, the priority has now become about 10 billion by 2050 (FAO, 1996). not just sustainable agriculture, but The increase in population and sustainable livelihoods based on subsequent rise in the demand for agriculture too. If the modern agricultural products are expected to be agriculture to be sustainable, it is greater in regions where the production expected to contribute towards these is already insufficient, particularly in goals.

1Plant Breeding Division, Tea Research Institute of Sri Lanka, Talawakelle, Sri Lanka . 34

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DISCUSSION 2004). Hence, it has been realized that further expansion of this high-input Farmers’ adoption and perception of model of agriculture would not be modern varieties sustainable, due to the high cost entailed and the negative impact on Since the first modern varieties (MVs) natural resources (Conway, 1998; were released during the late 1960s Singh, 2000). and early 1970s, the area planted with MVs has continued to expand. While it Limitations in formal plant breeding is clear that MVs developed through systems plant breeding programs (the characters of MVs are determined by Despite many advantages towards the objectives of ) have contributing to crop variety brought benefits to millions of development, the formal or producers and consumers, over time, conventional plant breeding (FPB) the adoption of MVs has lagged in programs also have some some areas, including many “marginal shortcomings. environments” (Almekinder & Louwaars, 1999). “ Marginal In conventional crop improvement environments” are defined as areas process, which is highly centralized, where agriculture is dominated by researchers make all decisions in variation in agro-ecological and socio- breeding varieties and verifying their economic conditions, resulting in performances. Most breeding programs complex stress and high production identify a core set of priority traits (by risk or low production potential . the scientists) and work to incorporate Among the factors that have those traits into the new varieties. The contributed for slow spread of MVs high-yielding varieties developed by into marginal environments has been the formal research system or FPB are the unsuitability of many MVs for often high-maintenance varieties and specialized production and have largely been suitable for resource consumption requirements of people rich and HPPSs. For many farmers who live in these environments, such conditions simply do not exist, especially the resource poor-farmers and as a result they obtain poor results (Elings et al., 2001). from high-tech varieties offered by the formal research systems. Many of It is commonly assumed that farmers these farmers reject the plant breeders’ in high potential production systems offerings simply because they were not (HPPSs) have much better access to designed for marginal farmlands; they modern technologies than in marginal meet neither the farmer’s needs nor environments. In many instances, plant local preferences (Almekinders & breeding has been beneficial to farmers Louwaars, 1999). As a result, old who enjoy favorable environments or varieties still dominate cultivation in those who could profitably modify those marginal environments, their environment to suit new , suggesting that farmers are failing to especially the MVs. These constraints benefit from modern plant breeding effectively put the MVs beyond the products. reach of millions of small-scale/ subsistence farmers who cannot afford In addition, in the varietal evaluation the high-priced inputs to get the process, after conducting on-station desired output (Morris & Bellon, evaluation (often under optimum input

35 M.T.K. Gunasekare conditions), better varieties are and develop a new paradigm that is identified by the /researcher need-oriented and address diverse and made them available for the socio-economic conditions, production farmers to test their preferences using environments and management only a limited number of varieties practices. merely selected to meet the objectives of the breeder. As a result only few The emerging local approach to plant “best” varieties are finally developed breeding and disseminated as a blanket recommendation in response to the In an effort to overcome some of the varied needs of farmers. This is mainly limitations in formal traditional because national plant breeding approach to plant genetic programs do not always have sufficient improvement, there is a growing resources to do extensive multi- recognition and interest in farmer location testing of varieties, covering participatory approaches in response to all possible variable environments. the challenge of making agriculture Hence, this kind of a formal approach more sustainable (Witcombe et al., poorly addressed the actual needs and 1996). Although the social distance of preferences of farmers since they only scientists from farmers varies from had the options to accept or reject a crop to crop, there is a possibility of few finished crop varieties at a very considering farmers as partners in crop later stage in the crop improvement improvement programs from the initial program. This so-called cultivar stages of breeding and selections development work is justified when a (Witcombe, 1996). crop is grown in large, ecologically homogenous production environments. There are many variants of farmer Although it may be possible to participatory approaches in crop overcome some of the related problems improvement. These approaches based by conducting on-farm varietal testing, on the local crop improvement that that also tends to be very resource benefit from contribution by both plant intensive, especially in developing breeder and farmer (Soleri et al., country setting. For this reason, most 2000). This can potentially result in plant breeding programs base their varieties adapted to the needs of selection decisions on data generated farmers with low resources in highly through on-station trials. This can lead stress- prone environments, and lead to to problems, because research has enhanced on-farm ( in-situ ) shown that varieties often perform conservation of crop genetic resources differently under farmers’ management (Almekinders & Louwaars, 1999). practices than they do under researchers’ management practices Definitions and Strategies (Almerkinders & Louwaars, 1999). The lack of consensus about Faced with the evidence that MVs terminology is common when a new developed for favorable production science is at its early stages, and conditions have not always diffused Participatory Plant Breeding (PPB) is readily into marginal environments, no exception (Sperling et al., 2001). plant breeders started searching Terms commonly used include, strategies to overcome the problems Informal Research & Development related to varietal development. These (IRD); Collaborative Plant Breeding issues forced the scientists to rethink (CPB); Farmer Participatory Breeding

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(FPB); and Participatory Crop Rationale for PCI- Farmers’ agendas Improvement (PCI). According to first Witcombe et al., (1996), PCI can be categorized into participatory varietal According to Weltzien et al., (2000), selection (PVS) and participatory plant PCI is expected to produce more breeding (PPB); farmer selection of benefits than the formal or finished or near-finished varieties is conventional crop improvement known as PVS, while farmer selection models in situation where a highly with unfinished material with a high centralized approach is inappropriate. degree of genetic variability is know as It is also evident that PCI is the only PPB. The degree of farmer possible approach to crops participation is another dimension for grown in unfavorable conditions or classifying PPB (Sperling et al., 2001). remote regions, in areas not large All such terminologies presently use enough to justify the interest of large describe broadly the same activities of breeding programs, and to breed for multifaceted technical and minor crops neglected by both private organizational collaboration in plant and public plant-breeding programs breeding by scientists and users of (Ceccarelli, et al, 2001). their results (Sperling et al., 2001). The principal reasons for increasing Moreover, the term PPB does not refer the involvement of farmers in crop to a single, well defined method for improvement programs can be outlined plant genetic improvement; rather, it as follows: refers to a set of breeding methods characterized by many different (1) Different expectations - Different potential forms of interaction between criteria – Addressing divers needs farmers and breeders. It has been identified that end-users (stakeholders) participation is essential PCI concept builds on the recognition in developing varieties acceptable to of farmers’ capacity to select what best them (i.e. farmer-preferred varieties), fits for their environment and the as their selection desires may be quite fundamental rationale for the different to breeders’ acceptability approaches is that joint effort can criteria (Soleri et al., 2000; Courtois et deliver more than when each actor al, 2001). It is apparent that the work alone (Witcombe et al., 1996). It farmers’ selection criteria, largely does not suggest that this approach is based on environment factors, were an alternative or complete substitute quite different from those used by the for conventional on-station and in- formal breeding programs laboratory agricultural research. The (Almekinders & Louwaars, 1999). The essential advantage of PCI over diversity of needs of end-users in terms conventional breeding is that it of food, beverages and other purposes involves farmers in developing, highlights the fact that crop varieties adapting and adopting new varieties; often have multiple uses and can only setting breeding goals according to be met by planting and maintaining a their requirements. Farmers become portfolio of crops and varieties (Atlin increasingly involved in the generation et al, 2001). Yield is not only defined of technology rather than being simple by the grain, root or tuber production, recipients of new agricultural but rather is an optimum function of technology. production of different plant parts and uses, eg: young leaves as vegetables, grains for seed and food, dried stalks

37 M.T.K. Gunasekare for fodder/animal feed etc), (Smale & breeding line (Banziger & Cooper, Bellon, 1999). The absence of these 2001). characteristics in varieties would lead to a rejection by small-scale farmers, Falconer (1989) pointed out, direct even if they were high yielding. It selection in the target environment (or appears that in these cases non-yield in an environment identical to the requirements are much more important target) is always the most efficient. than breeders anticipated, and hence be This can be achieved by selecting crucial for the adoption or rejection of directly in each target environment, a new crop varieties (Ceccarelli, et al., type of selection defined by 2001). This suggests that with the PPB Simmonds, (1984) as decentralized approach breeders should be opened to selection. In PCI approach, GEI is unexpected and unplanned selection greatly reduced since selection is criteria. always done in the target (production) environment. In this situation farmer- Another aspect of PPB is that it driven trials become important to provides a means of assessing develop cultivars to suit their needs “subjective traits” such as taste, aroma, since targeting heterogeneous and appearance, texture and other remote environments are difficult to characteristics that determine the address through a centralized formal suitability of a particular variety for (Almekinders & culinary use. These traits are difficult Elings, 2001). Almekinders & Elings, to measure quantitatively, because they (1999) acknowledge GE interaction as are a function of human perceptions. an important issue and justification for Identification and evaluation of PCI or PPB. subjective traits require close collaboration between plant breeders, (3) Supporting genetic diversity social scientists, and farmers. Bellon Today’s agriculture is like a huge (2001) has reviewed methods being inverted pyramid. Globally it rests on a developed by PPB practitioners to help precariously narrow base. Less than in identifying and analyzing subjective 3% of the 250 000 plant varieties traits. available to agriculture are in use today (www.idrc.ca/seeds). The top-down (2) Evaluation directly on target system of agricultural research, where (production) environment farmers are seen merely as recipients A fundamental problem in plant of research rather than as participants breeding is the relationship between in it, has contributed to this selection environment and target dependence on a relatively few plant environment. The selection efficiency varieties. This trend and the increasing decreases as the selection environment industrialization of agriculture are key becomes increasingly different from factors that can be describe as “genetic the target environment in terms of erosion”. However, the breeding model climate, soil and agronomic based on PPB methods encourages the management etc. (Altin at al., 2001). maintenance of more diverse, locally When the selection environments are adapted plant populations while very different from the target promoting cultivar development environments, genotype – environment (Ceccarelli et al., 1997; Joshi & (GE) interaction usually gain Witcombe, 1996). Witcombe et al importance because they change the (2001) discussed increasing genetic relative ranking of the performances of diversity by PVS in HPPSs too.

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(4) Speedy varietal adoption rate 2001). Hence, in PPB approach, Farmer participation in selection under farmers are free to practice the same their own environmental and level of management in the trial as they agronomic conditions not only benefits had previously. The idea is that if the the selection process but also speeds new variety developed through PPB up the transfer and adoption of new can really provide better yield under varieties (Sperling, et al., 2001) the existing conditions, no additional without the involvement of complex expenditure need to be involved in mechanisms of variety release, adopting the new variety. extension services etc.. Although relatively little work has been done to Applications in modern plant document the speed of PPB compared breeding programs to conventional breeding, recently evidence has started to emerge There is a belief that PPB is only suggesting that PPB and PVS can lead feasible and work particularly well to earlier adoption of new varieties with subsistence farming with minor (Joshi & Witcombe, 1996; Ceccarelli, crops or under marginal conditions. et al, 2001), with no major additional However, there are contemporary cost (Witcombe et al., 2003). evidences where PPB approach was According to Joshi et al., (2001) a found successful in applying in modern variety breed by PPB showed steady plant breeding programs too. A classic increase in adoption and its spread example of such participatory commenced 5-6 years earlier than approach relates to Dutch would have been the case in a breeding (Almekinders & Louwaars, conventional system. 1999). Breeders in potato breeding companies in the Netherlands, make (5) New varieties to grow with the the crosses between particular parents. existing package Seeds of those crosses are given to The current agricultural production farmers who perform the main practices are highly dependent on selection work over a number of expensive technology, and chemical seasons. The farmers subsequently inputs, and are simply not sustainable send the selected tubers back to the in the long run. However, any new company for screening for pests and agricultural technology should bring diseases, after which the farmer and economic benefits to be adopted and breeder discuss the commercial accepted by farmer. In many instances prospects of the new selection. although farmers are interested in Promising varieties are registered and using recommended inputs, these are commercial revenues for the sale of the often not available timely in sufficient variety are shared between the farmer quantity to meet their demands to and the breeding company. PPB realize the potential of the new variety methods have been applied in Nepal (Courtois et al., 2001). With the for developing farmer-preferred rice outcome of the formal plant breeding varieties to HPPSs with few production products, farmers need to manage and constraints (Joshi, 2000). Hence, it is control the environment to fit the evident that the PPB is suitable not genotype. In contrast, with PPB only for marginal but also for HPPSs approach, the genotypes suitable are and in modern plant breeding identified to fit existing environment programs. rather than changing the environment to fit the genotype (Ceccarelli, et al.,

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Criticism of the approach evaluation trials. However, there are strategies adopted to overcome this Despite the advantages discussed issue, which include tools to aid above, there are number of criticism discussions with farmers, proffered by scientists due to modifications in field layout and misconception of the approach design of on-farm testing and use of (Witcombe, 1996), which are outlined participatory evaluation methodologies below: (Almekinders & Louwaars, 1999). During the testing period, farmers and (1) Transfer of technology vs PCI breeders have the opportunity to Some scientists claim that the discuss the merits of each material participatory approaches by extension amongst themselves. Joint evaluation services are already being used. also involves the breeder/scientists Although traditional extension visiting the farmers at different stages methods can involve farmers, they of crop development to discuss the often rely on demonstration of a few performances hence, confirm the recommended varieties, grown by validity of the data and their reliability. extension workers with a recommended package of practices. In (4) Cost effectiveness contrast, with PCI, the main objective Another criticism over the approach is is not to transfer technology, but to that the products of the PPB will not be empower farmers to learn, decide, cost effective as they are meant for adapt and do better with the assistance niche environment hence, cannot be of scientists and extension agents cultivated on a wide range of rather than just testing the technology, environment. Another issue is that which clarifies the distinction between without a formal release, the spread of participatory approach and transfer of varieties will be too limited to justify technology (Witcombe, 1996). the cost, which is however not the case (Joshi, et al., 2001; Witcombe et al., (2) Risk to farmer 2003). Morris & Bellon, (2004) It is believed that PPB entails an suggest that return to investment will unnecessary risk to the farmers. increase if use of PPB methods Breeders however, can help reducing increases variety adoption level. the risk by providing farmers with Similarly, economic benefits will be advanced lines/breeding material. created if use of PPB methods Farmers manage risk exceptionally accelerates adoption of new varieties well with the fewer resources they by reducing the time required to have. They never grow a new variety develop them (Pandey & on a large area for the first time they Rajataserrekul, 1999). cultivate it, unless they are sure of the performances of the new variety Key challenges (Witcombe, 1996). While the opportunity seems very (3) Reliability of results promising, there are likely to be some Some may question about the bottlenecks in the PPB. The increase in reliability of the results/ data generated participatory plant breeding and other from on-farm trials since breeders and collaborative programs involving varietal release committee would like farmers, their communities and formal to have data generated from sector scientists raise new questions statistically or formally designed and challenges for recognizing

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collaborative innovation in plant varietal approval guidelines (Morris & breeding: Bellon, 2004), suggesting that existing regulatory procedures may have to (1) Implications for institutions and undergo major revisions to technical challenges accommodate benefits realized through The institutional changes required PPB. Policy changes arising from such include transformation of attitudes and initiatives will take time, but the case behavior and linking informal with will be strengthen by exposing more formal research and development. The and more organization to the benefits difficulty of effecting major changes of PPB/PVS and building their and reversals in large organizations capacities to participation. underline the importance of seeing what changes of behaviors and (3) Intellectual property right (IPR) attitudes are required, what IPR and related issues are among the institutional conditions are needed for many challenges ahead for PPB. When them to be sustained and spread, and the system alters to suit the needs for how these might be achieved carrying out PCI, such as considering the nature of the crop decentralization of testing to off- handled. station sites, farm-trial design which Another key challenge is to set up the farmers are able to interpret for organizational models that allow the themselves, and which are conducted devolution of decision-making and on- under “real farmer” input levels, raises farm testing to the local level. It is the issue of IPR. If a farmer develops necessary to develop better strategies an improved variety in collaboration for supporting particularly, minor with the formal research system, who crops and those that do not come owns the right to that variety? who within the mandate of the formal access and can distribute it? and how research system. will the various benefits be shared? Currently in most countries, IPR (2) Variety registration systems offer little recognition to the A clear constraint to PCI approach is role played by farmers in plant the current regulatory framework that breeding (Morris & Bellon, 2004). makes it practically impossible to gain Some agencies believe that it is official recognition of the suitability of important to establish revised IPR a variety for cultivation. Regulatory regimes capable of equitably assigning authorities in many countries are still credit to both farmer and the breeder not willing to consider data generated (www.idrc.ca/seeds ). using participatory methods when they evaluate varieties for registration and (4) Economic challenges release (Morris & Bellon, 2004). In a world of limited resources, Results of on-farm trials are seldom research must be cost effective. taken into consideration in official Numerous case studies have estimated varietal release procedure (Virk, 1998). the returns to investment in In most countries, new plant varieties conventional plant breeding programs, are approved for release only if they but the results tend to be specific to a differ in some significant way from particular location, organization, and varieties that have already been crop (Morris & Bellon, 2004; Pandey released. “ Subjective trait” & Rajataserrekul, 1999). Much less performance data generated through empirical work has been done to assess PPB are usually not recognized in the returns to investment in PPB

41 M.T.K. Gunasekare programs, which is not surprising that Success stories: Contemporary PPB methods are still new. Despite evidence several technical reports on the success of PPB, more analysis is required to Some preliminary reports indicated the assess its economic impact. Economic positive impact of various forms of evaluations of PPB continues to be participatory approaches in increasing limited by methodical problems, biodiversity and adoption of varieties especially when it comes to estimating both in favorable and less favorable the benefits resulting from environments (Witcombe, et al., 2001). improvements of “subjective traits”, Successful experiences which one of the key advantages associated illustrated the potential of farmer with PPB approach (Almekinders & participation in breeding include, Elings, 2001). Hence, it has become incorporation of cold resistance in necessary to generate improved local rice varieties in Nepal, addressing knowledge about the economics of a need of a group of farmers which plant breeding so that the integration of was considered too small or too little formal and participatory plant breeding importance for FPB to be addressed approaches could be based more (Sthapit et al, 1996); experiences with explicitly on economic considerations. pearl millet in Rajastan, India (Weltzien, et al., 1996) and the On the cutting edge - selection of bean varieties for complex vs PPB and marginal conditions in Ruwanda (Sperling & Scheidegger, 1995). It is worth noting that the potential Ceccarelli et al. (2000) demonstrated extensive application of genetic farmers’ capacity in handling engineering techniques does not segregated population and in selecting eliminate the need for breeding high yielding barley entries under programs to cope with GE interaction harsh and marginal environments because almost no cultivar can compared to breeders in Syria. assemble genes conferring superior Likewise, in Jordan it was reported that performance in all environment types under farmers’ local conditions, the within a relatively large region efficiency of farmers in identifying and (Witcombe, 1996). Also the possible selecting high yielding barley selection for yield based on molecular genotypes was found to be better than markers may require preliminary the efficiency of the plant breeders definition of adaptation and yield (Bishaw, 2004). In Colombia, a stability targets, since a remarkable comparison has been made between portion of useful markers are farmers’ and breeders’ selection for environment-specific (Hayes et al., cassava. It was concluded that breeders 1993). In a wide adaptation prospect, tend to select for yield and stress marker-assisted selection (MAS) may tolerance while farmers place greater prove distinctly less effective than emphasis on quality traits (Witcombe, multi-environment, phenotypic 1996). Understanding the complexity selection for yield in the presence of of the local farming system, farmers’ relatively large GE interaction (Cooper seed management and the value of et al, 1999). The evidence presented characteristics of local materials was a indicates that these new approaches key to the success of millet work in and methods involving participatory Rajastan (Weltzein, 2000). Significant tools could serve the complex, divers genetic progress has been made for and risk-prone agriculture. grain yield of while providing

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sources of tolerance to the set a new pace in crop improvement environmental stresses in the low input programs worldwide. However, due to rain fed production system in Australia various challenges related to the (Basford & Cooper, 1998). Over 70 approach, the potential applications cases of PPB are documented, and their implications are still to be involving a range of crops and explored. Although much of the geographic regions (McGuire et al., emphasis has been placed on 1999). developing new varieties for marginal areas, PCI approach has proved its The few examples highlighted here and application in modern plant breeding the other successful examples programs too. Developments in this convinced that the PPB approaches area also suggest that PCI could were simple, effective and worthy of equally be applied to develop varieties wide adaptation. Therefore, for HPPSs. As the participatory participatory approaches appeared to method in crop improvement is an be useful in developing varieties that emerging new concept, some criticism are more likely to adopted by farmers over the approach and some than conventional plant breeding for controversial arguments still exist. niche environments; i.e. “Adapting While the opportunity seems very crops to environments and clients”. promising, this approach in plant breeding raises new questions and CONCLUSIONS challenges in relation to institution and economical aspects. The prediction is The aim of the PPB is to ensure that that PCI could offer tremendous the research undertaken is relevant to opportunity to increase agricultural the farmers’ needs. The success stories production, perhaps not less than that of generating farmer-preferred offered by biotechnology, to improve varieties through PCI approaches have the food security.

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