The impact of participatory plant breeding (PPB) on landrace diversity: A case study for high-altitude rice in Nepal

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1 Euphytica 134: , Kluwer Academic Publishers. Printed in the Netherlands. 117 The impact of participatory plant breeding (PPB) on landrace diversity: A case study for high-altitude rice in Nepal K.D. Joshi 1 & J.R. Witcombe 2, 1 Local Initiatives for Biodiversity, Research and Development (LI-BIRD), Pokhara (Present address: DFID Plant Sciences Research Programme, CIMMYT South Asia Regional Office, P. O. Box 5186, Kathmandu Nepal); 2 Centre for Arid Zone Studies, University of Wales, Bangor, Gwynedd LL57 2UW, U.K.; ( author for correspondence; j.r.witcombe@bangor.ac.uk) Received 1 November 2001; accepted 18 July 2003 Key words: adoption, diversity, genetic resources, landraces, participatory plant breeding (PPB) Summary Participatory plant breeding (PPB) methods were used to develop two farmer-accepted, cold-tolerant rice varieties in Nepal Machhapuchhre-3 (M-3) and Machhapuchhre-9 (M-9). Both were derived from the cross Fuji 102/Chhomrong Dhan. Following the introduction of these varieties, the changes in the rice landraces and varieties that farmers grew were studied in ten villages. In seven of them for which data were analysed for both 1996 and 1999, adopting farmers grew 18 landraces and four modern varieties of which three, M-3, M-9 and Lumle-2, were the products of PPB. These three varieties covered 10% of the total rice area and 33% of the rice area of the adopting farmers in the seven study villages in the 1999 survey. The adoption of the PPB varieties impacted most on the more commonly grown landraces. With the exception of two villages, the varietal richness among adopting farmers was either static or increased, and there was an overall increase in allelic diversity. However, in future, the increasing adoption of M-3 and M-9 could result in significant reductions in varietal richness, although, allelic diversity may not be greatly reduced. Introduction Participatory plant breeding (PPB) is increasingly being used for decentralised crop improvement (IPGRI, 1996; Sthapit et al., 1996; Witcombe et al., 1996; Weltzein et al., 2000; Witcombe, 2001). Important elements of PPB are, commonly, screening of segregating materials in the target environment, and the participation of farmers in goal setting, selection and evaluation. PPB typically uses a local landrace or a locally adopted variety as a parent in the breeding programme. The use of landraces has not been common in conventional breeding in Nepal. Including Machhapuchhre-3 (M-3), a product of PPB, only five out of the 48 rice varieties (8%) released from 1959 to 2002 have a Nepalese landrace as one of the parents. In these five varieties, only three landraces, Chhomrong Dhan, Jarneli, and Pokhreli Masino, have been utilized and Pokhreli Masino was a parent in three of them. A sixth variety had the Nepalese landrace Jumli Marsi as a grand parent. This compares to the 2500 rice landraces that have been collected in Nepal, although some of them are likely to be duplicates (Gupta et al., 1996). Nepal is a small country with highly diverse agroecological conditions, and socio-economic and cultural settings, which favour the use of many, diverse varieties and crop species. Hill agriculture, in particular, relies on indigenous knowledge, local inputs and resources and a diverse range of crop landraces. In spite of much investment in agricultural research and extension, the adoption of modern varieties is relatively low in the hills and the mountains of Nepal (LARC, 1995; Chemjong et al., 1995). Centralised plant breeding has had little success in providing a choice of varieties to these areas and, particularly in higher altitude regions, local landraces are widely cultivated.

2 118 Table 1. Households and rice area in the seven study villages. Mid-hill = m altitude; high-hill = m; mountain = >2000 m Zone Village Households (number) Rice area (ha) in the surveyed data for all sampled village in village households Mid-hill Patlikhet Marangche Kande High-hill Chane-Kimche & Landruk-Tolka Chipleti Mountain Chhomrong & Ghandruk Bhakimle Total The use of decentralised, participatory methods could remove this constraint to the adoption of new rice varieties. However, the products of PPB, if highly preferred by farmers, could have a considerable impact on local agro-biodiversity. A wide diversity of rice landraces are grown under varying soil types, moisture regimes and fertility levels and under adverse conditions such as land with cold water irrigation and shaded areas. In recent years, there has been a growing awareness of the value and utility of agro-biodiversity and local non-governmental organisations and international organisations are concerned about their conservation and utilisation. One of the various possible impacts that modern varieties, from whatever source, could have on landrace diversity is on varietal richness (the number of landraces and varieties grown) and allelic diversity (the genetic diversity of the landraces and varieties grown). This paper examines the possible impact of PPB varieties on the diversity of rice landraces in high altitude villages in western Nepal. Materials and methods Participatory plant breeding of high-altitude rice was initiated in 1993 by the Lumle Agricultural Research Centre (LARC) in the villages of Chhomrong and Ghandruk, (both at 2000 m altitude) of Kaski district, Nepal to develop farmer acceptable rice varieties from crosses between a local landrace and cold tolerant exotic parents with disease resistance and white grains. Scientists from the Nepal Agricultural Research Council (NARC) chose the exotic parents from the International Rice Cold Tolerant Nursery (IRCTN) at Khumaltar (1350 m). Eighteen farmers collaborated in selecting between, and sometimes within, ten F 5 bulk lines derived from three crosses made by the Agricultural Botany Division of NARC (Sthapit et al., 1996). As a result of this programme, in June 1996, the Variety Release and Registration Committee (VRRC) of Nepal made the first release of a variety produced with the extensive use of participatory methods Machhapuchhre-3 (Joshi et al., 1996). In 1995, Machhapuchhre-9 (M-9), a sister line of M-3, was identified as an acceptable variety by farmers at Chhomrong from the National Rice Cold Tolerant Nursery (NRCTN) and in 1996, by farmers at Marangche from participatory varietal selection (PVS). From 1996, M-3 and M-9 were introduced into villages situated between 1300 m and 2300 m altitude by non-governmental organisations (NGOs) such as the Local Initiatives for Biodiversity Research and Development (LI-BIRD), CARE Nepal, the Annapurna Conservation Area Project (ACAP) and by the government organisation LARC. The adoption and spread of M-3 and M-9 were monitored from 1996 to The farmers were considered as adopters if they had grown the variety for at least two seasons, or had deliberately obtained the seeds from another farmer and grown the variety in Surveys in five villages in 1996 (listed in Table 1 except Chipleti and Bhakimle), eight villages in 1997 (the 1996 villages plus Bangsing Deurali, Bagephadke and Khanigaon Lwang) and 10 villages in 1998 (additionally Chipleti and Bhakimle) were used to identify farmers who were adopting either M-3 or M-9 by tra-

3 119 Table 2. Varietal richness in 100 sampled households in the seven study villages, 1996 and 1999 Zone Village Adoption of PPB Varietal richness in varieties (% area) surveyed households of households of village change (%) Mid-hill Patlikhet Marangche Kande High-hill Chane-Kimche & Landruk-Tolka Chipleti Mountain Chhomrong & Ghandruk Bhakimle Total Table 3. Adoption of Machhapuchhre-3 and Machhapuchhre-9 in the seven study villages by altitudinal zone in 1999 Zone Adoption Overall adoption (% of household area) (% of total area) M-3 M-9 M-3 and M-9 Mid-hill High-hill Mountain All zones cing the spread of seed from farmer to farmer across these three years. Further information on all 10 villages is given in Joshi et al. (2001). We report on the seven villages for which data were obtained in the 1999 survey for both 1996 and Farmers adoption intentions, to assess the possible impact of PPB products on rice landrace diversity, were collected during the 1998 surveys. The 138 farmers who were known to be possible adopters from the 1996, 1997 and 1998 surveys were then included in a survey covering 10 villages in 1999 and 127 of them proved to be adopters. The adoption data in the 1999 surveys are reported here for the 100 farmers from the seven villages for which 1996 data were also obtained (Tables 1 and 2). Hence, sampling was purposive (only those households were surveyed who were known to have been given seed of M-3 or M-9 by the project or had received seed from other farmers from within the village or outside). The survey covered about 30% of the rice growing area in the surveyed villages (Table 1). Information was collected from the surveyed households using semi-structured interviews. The 1999 survey also collected information on the landraces farmers grew in In the 1999 survey, for each household, the total area of khet land (irrigated and bunded terraces of land where rice is grown) was determined from the land ownership certificates and a total inventory of rice landraces and modern varieties, with the area that each variety occupied, was compiled. Sometimes the same landraces were known by more than one name. For example Maisare was also known as Takmare, Raksali as Galaiya, Rakse as Rause or Bhalu and Tarkaya as Tarkange. Landraces with synonyms were combined in the analysis of landrace diversity. The rice varieties and landraces were analysed by the area in which they were grown and the number of households that grew them. Changes between 1996 and 1999 were assessed for area and household number for the more common landraces. The statistical significance of change in area was determined by a two-tailed paired Student s t test between the areas reported for each household for 1996 and Results and discussion Adoption of M-3 and M-9 in 1999 The extent of adoption was determined by altitude and time of entry into the village. M-3 was introduced to all the ten study villages and was adopted in all of them, while M-9 was introduced to seven of the villages, but was adopted in only three mid-hill villages. Hence, there was a clear trend for M-3 to be adopted more than M-9 in higher-altitude villages (Tables 2

4 120 Figure 1. The study villages (solid circles) in Kaski, Myagdi and Syangja districts, Nepal.

5 121 and 3). The lower average adoption in the high-altitude villages was mainly because of the low adoption in Chipleti where the new varieties were not introduced until 1998, only one year before the survey. The adoption of varieties at high altitudes is determined by their cold tolerance and disease resistance. Cold air and water cause high levels of spikelet sterility and blast and sheath brown rot is endemic at higher elevations. Farmers in Chhomrong and Ghandruk villages reported that M-3 was less cold tolerant than Chhomrong Dhan (Joshi et al., 2001). They also reported that M-9 was even less cold tolerant than M-3 and hence more specifically adapted to mid-altitude villages. By 1999, six years after the commencement of the PPB programme the products of PPB occupied about 10% of the total rice area of all 7 villages (Table 2) some of which did not receive seed until There is a continuing trend of increasing adoption of M-3 and M-9 in both area and household number. In the past, in spite of concerted efforts by Government extension agencies to promote modern rice varieties their adoption was very poor. For example, only 10 11% of all farming households were growing improved rice cultivars in a survey of 1688 households in 11 districts of Eastern and Western Nepal nearly three decades after the intervention of improved varieties (Chemjong et al., 1995; LARC, 1995). Impact of M-3 and M-9 on varietal richness Even if the genetic relationships between all of the varieties were known, an analysis of change in weighted diversity, from 1996 to 1999 would reveal little change as a result of the 10% adoption of M-3, M-9 and Lumle-2 in 1999 since these varieties would only contribute 10% of the weighted diversity. However, varietal richness, the total number of genotypes present in an area (Frankel et al., 1995), was examined (Table 2). The total number of rice cultivars decreased little in the adopting households despite the adoption of varieties produced by PPB that might have been expected to replace several of the landraces. The number of rice cultivars grown by the adopting farmers in 1999 increased in four of the study villages, decreased in two, while in one of the villages there was no change (Table 2). The decrease in varietal richness for the adopting farmers in Chhomrong and Ghandruk is unsurprising since the initial PPB programme was conducted in these villages. In the early stages of PPB programme, as many as nine PPB lines were grown in 1996 at Chhomrong alone, but by 1999 the undesirable lines had been dropped. In Chane-Kimche the decrease was because households adopting M-3 increased area under it (34% of the area of the area at the adopting household level) dropping the landraces Tairige and Takmare, even though M-3 covered only 6% of the total rice area. For adopting households the rice area that was under landraces in 1996 had to decline by 1999 because of the adoption of M-3 and M-9. Although this did not usually result in a decrease in varietal richness (Figure 2), allelic diversity has probably increased. M-3 and M-9 have exotic variety Fuji-102 as a parent. Many of the alleles of Fuji-102 have been inherited by M-3 and M-9 rather than from the other, locally-grown, parent Chhomrong Dhan; molecular diversity studies (Steele, Bajracharya and Edwards, pers comm.) on simple sequence repeats (SSR) show that for 12 polymorphic loci M-3 and M-9 were 42% dissimilar to Chhomrong Dhan. Impact of M-3 and M-9 on landrace replacement Varietal portfolio There was a good varietal diversity in both 1996 and 1999 (Table 2, Figure 2). In the ten study villages, rather than just the seven considered in more detail, there was just one more landrace and the same 5 modern varieties. Of the five modern varieties, three were the products of PPB (M-3, M-9 and Lumle-2). In 1996, four landraces and two modern varieties were grown by more than 10% of the sampled households and about half of the varieties and landraces were rare, being grown by only (1%) of the sampled households (Table 4). The average area devoted to any landrace by the households in the study villages averaged over 1996 and 1999 was quite small (<0.3 ha) (Figure 2). Joshi et al. (1999), while studying the occurrence and diversity of local landraces in Kaski (a low to mid hill site, 750 m to 1300 m) and Bara ( m) found that only a few landraces were widely grown. The great majority of landraces or varieties were less common and had either, or both, a small area and few households growing them. Farmers perceptions on landrace change in 1998 In 1998, the farmers perceptions on the impact that PPB products would have on local landrace diversity were recorded. Most of the respondents reported that they would increase the area under M-3 or M-9. About 24% of the respondents reported that the adoption

6 122 Figure 2. Area per household, and number of adopting households of rice landraces and varieties in the seven study villages. Average of 1996 and of M-3 or M-9 would either reduce the area under landrace Kathe or entirely replace it. A similar situation was perceived for landraces Kalopatle (8% of respondents), Maisare (6%), Raksali (3%) and Darmali (3%). A further 10% of the surveyed households also mentioned the possible partial replacement of eight other landraces and one modern variety. No households reported they would entirely replace the landrace Chhomrong Dhan or the modern variety Khumal 4, even though for the remaining 17 landraces at least one household mentioned the complete replacement of at least one of these in the near future. Changes from 1996 to 1999 in landrace adoption The 1999 survey confirmed the major perceptions identified in the 1998 survey. The area and number of adopting households increased significantly for M-3 and M-9 (Figures 2 and 3) and Kathe reduced in aver-

7 123 Table 4. Summary of the relative abundance of the landraces and varieties in the 100 sampled households in the seven study villages, 1996 Description Number Names of common varieties and landraces Total landraces 18 Total varieties 5 Landraces grown by >10% households 4 Chhomrong Dhan, Kathe, Darmali, and Sinjale Varieties grown by >10% households 2 Machhapuchhre-3 and Machhapuchhre-9 Landraces grown by only 1% households 8 Varieties grown by only 1% households 3 Figure 3. Area and household adoption of rice landraces and varieties in the seven study villages that significantly changed in average area of adoption from The significance of the change in area is indicated = p 0.05; = p 0.01; = p Arrows indicate the direction of change from 1996 to 1999.

8 124 age area and was grown by fewer households. Despite this increase in M-3 and M-9, most of the landraces showed no significant change in area from 1996 to This was particularly true of the least common landraces that were grown by fewest households. The number of households remained static, and the area remained the same or did not change significantly, for 12 of the rice landraces and varieties (indicated by open circles in Figure 2). The change in area from 1996 to 1999 was statistically significant for eight of the twelve most common landraces i.e., Chhomrong Dhan, Kathe, Kalopatle and Sinjali (p 0.001), Raksali and Rakse (p 0.01), and Darmali and Maisare (p 0.05) (Figure 3). These included the three landraces grown by most households (Chhomrong Dhan, Kathe and Kalopatle). Hence, it was mainly the most common landraces that had declined in area from 1996, and the less common landraces were the most buffered against change (Figures 2 and 3). In all cases, this decrease was largely accounted for by a compensating increase in M-3 and M-9. Of these eight landraces, for five of them farmers had mentioned in the 1998 surveys that their area would be reduced. However, the decline in the popularity of Raksali and Kalopatle was more complex. The number of households growing Kalopatle declined greatly, but those farmers that continued to grow it did so on a larger average area. This was because the households that no longer grew it had only done so on a small area. For Raksali, the decline in average area per household was accompanied by an increase in the number of households that grew it so the new adopters only grew it on a very small area. Varietal change is a common and continuing process in most subsistence farming where farmers allocate different proportions of their land to a cultivar from one season to another. Landraces that most closely matched the new varieties, but had a lower yield or other undesirable traits, were replaced first. The landraces with the greatest reduction in area and adopting households were Chhomrong Dhan, Kathe and Kalopatle. The niches of these varieties closely match those of M-3 and M-9 and farmers reported that they had more stable grain and straw yields under varying fertility and moisture levels and other stress conditions such as under shade. Most of the landraces matured later than the Machhapuchhre lines. The duration of a variety is very important in higher elevations to allow a succeeding crop to be sown in time. The decrease in area and number of growers of red-grained Chhomrong Dhan may have been influenced by the preference of farmers for white-grained M-3 and M-9. Farmers management of on-farm biodiversity is a very dynamic process. Farmers rarely use new varieties to replace their existing crop genetic resources altogether, particularly in risky marginal areas; rather, they add new materials to their existing varieties portfolio. So the likelihood that, apriori, formal-sector seed supply to farmers in marginal areas would result in large-scale replacement of existing local crop genetic resources base is remote (Cromwell & Almekinders, 2000; Smale et al., 1995; Bellon & Brush, 1994). Brush (1995) reported that farmers maintain local varieties even while adopting modern varieties and modern agricultural technologies. Lohar & Rana (1998) reported that commercialisation does not always lead to genetic erosion in either subsistence or in commercial hill farming systems. They found that the introduction of modern varieties increased varietal richness in some villages. To conserve landraces, maintaining diversity at the community level should be sufficient. Although there was an overall loss in landrace richness in the sample it was not severe because farmers preferentially retained rare landraces that had specific adaptations and uses. M-3 and M-9 added to genetic diversity as they had inherited alleles from a genetically-distinct, exotic parent. Landraces found to be most at risk could be utilised in participatory plant breeding so that their useful alleles, which may impart specific adaptation to local conditions, are incorporated in more productive genotypes and hence conserved. For example M-3 and M-9 combined cold tolerance with higher yield and white grain while retaining the adaptability and other agronomic traits of Chhomrong Dhan. When farmers add M-3 or M-9 to the varietal portfolios they increase the food security of their households and conserve diversity. An important finding was that the adoption of PPB varieties was part of a dynamic process with overall losses or gains in varietal richness at the village level and in the areas of adoption of landraces and varieties. Ex situ conservation is simply a snapshot of a situation in the year in which the collection was made. PPB, by producing varieties that farmers like, contributes to the dynamism. It accelerates change by introducing genes and genotypes but may not be fundamentally changing the age-old processes of varietal adoption and loss. Indeed, as argued by Witcombe et al. (1996), PPB in its collaborative form

9 125 in farmers fields is a dynamic form of in situ genetic conservation. Acknowledgements This work was carried out with the joint funding from the Department for International Development (DFID), Plant Sciences Research Programme, UK and the International Development Research Centre (IDRC), Ottawa, Canada for the benefit of developing countries. The views expressed are not necessarily those of the DFID and IDRC. The authors wish to thank all the farmers who collaborated with the project and all of the LI-BIRD staff who helped conduct the research described in this paper. The authors are grateful to Dr Paul Hanacziwskyj for critical review and suggestions. References Bellon, M.R. & S.B. Brush, Keepers of maize in Chiapas. Econ Bot 48: Brush, S., In situ conservation of landraces in centres of crop diversity. Crop Sci 35: Chemjong, P.B., B.H. Baral, K.C. Thakuri, P.R. Neupane, R.K. Neupane & M.P. Upadhaya, The impact of Pakhribas Agricultural Centre research in the Eastern Hills of Nepal: Farmer adoption of nine agricultural technologies. Pakhribas Agricultural Centre, Dhankuta, Nepal. Cromwell, E. & C. Almekinders, The impact of seed supply interventions on the use of crop genetic diversity. In: C. Almekinders & W. De Boef (Eds.), Encouraging Diversity, pp Intermediate Technology Publications, London. Frankel, O.H., A.H.D. Brown & J.J. Burdon, The Conservation of Plant Biodiversity. Cambridge University Press, Cambridge, Great Britain, pp Gupta, S.R., M.P. Upadhaya & T. Katsumoto, Status of Plant Genetic Resources in Nepal. Paper presented at the 19th summer crops workshop, held at National Rice Research Programme, Parwanipur, Bara, Nepal, February Parwanipur, Nepal: National Rice Research Programme. IPGRI, Proceedings of the IDRC/IPGRI Workshop on Participatory Plant Breeding, July, International Agricultural Research Centre, Wageningen. P. Eyzaguirre & M. Iwanaga (Eds.), IPGRI, Rome, Italy. Joshi, K.D., B.R. Sthapit, R.B. Gurung, M.P. Gurung & J.R. Witcombe, Proposal for release of rice variety Machhapuchre- 3. Lumle Agricultural Research Centre, Kaski, Nepal. Joshi, K.D., D.K. Rijal, R.B. Rana, S.P. Khatiwada, P. Chaudhary, K.P. Shrestha, A. Mudawari, A. Subedi & B.R. Sthapit, Adding benefits I. Through participatory plant breeding (PPB), seed networks and grassroots strengthening. In: D. Jarvis, B. Sthapit & L. Sears (Eds.), Conserving Agricultural Biodiversity In Situ: A Scientific Basis for Sustainable Agriculture. Proc 3rd Global Meeting of in situ Crop Conservation Project, 5 12 July 1999, Pokhara, Nepal. Joshi, K.D., B.R. Sthapit & J.R. Witcombe, How narrowly adapted are the products of decentralised breeding? The spread of rice varieties from participatory plant breeding programme in Nepal. Euphytica 122: LARC, The adoption and diffusion and incremental benefits of fifteen technologies for crops, horticulture, livestock and forestry in the Western Hills of Nepal. LARC Occasional Paper 95/1. Lumle Agricultural Research Centre, Pokhara, Nepal. Lohar, D.P. & R.B. Rana, The dichotomy of crop diversity management issues in subsistence and commercial hill farming systems in Nepal. In: Tej Pratap & B. Sthapit (Eds.), Managing Agrobiodiversity-Farmers Changing Perspectives and Institutional Responses in the Hindu-Kush-Himalayan Region, pp International Centre for Integrated Mountain Development (ICIMOD), Kathmandu, Nepal and International Plant Genetic Resources Institute (IPGRI) Rome. Smale, M., P.W. Heisey & M.D. Leather, Maize of the ancestors and modern varieties: the microeconomics of high yielding variety adoption in Malawi. Econ Devel Cult Change 43: Sthapit, B.R., K.D. Joshi & J.R. Witcombe, Farmer participatory crop improvement. III. Participatory plant breeding, A case study for high altitude rice in Nepal. Expl Agric 32: Weltzein, E., M. Smith, L.S. Meitzner & L. Sperling, Technical issues in participatory plant breeding from the perspective of formal plant breeding. A global analysis of issues, results and current experiences. Working Document no. 3. CGIAR, Systemwide Program on Participatory Research and Gender Analysis for Technology Development and Institutional Innovation. Witcombe, J.R., A. Joshi, K.D. Joshi & B.R., Sthapit, Farmer participatory crop improvement. I. Methods for varietal selection and breeding and their impact on biodiversity. Expl Agric 32: Witcombe, J.R., The impact of decentralised and participatory plant breeding on the genetic base of crops. In: H.D. Cooper, C. Spillane & T. Hodgkin (Eds.), Broadening the Genetic Base of Crop Production, pp CABI Publishing, Wallingford, Oxon, UK.

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