Enhancing on-farm conservation of traditional rice varieties in situ through participatory plant breeding at three contrasting sites in Nepal

摘要

Participatory plant breeding (PPB) is one of the strategies employed for on-farm management of traditional rice varieties in three contrasting in situ conservation villages of Nepal. PPB programmes in Nepal were designed to investigate whether: 1. Traditional farmers' cultivars can be conserved per se; 2. PPB contributes to the enhancement of biodiversity by broadening the genetic base that provides benefits to community; 3. The PPB process encourages farmers to maintain the evolutionary processes that allow the crop to evolve over time, while remaining adapted to diverse, local production niches; 4. Landraces can be conserved by improving them for traits that farmers consider important to make them more competitive against alternative varieties. This paper describes the processes of PPB that encourages farmers to locate rice diversity and their custodians; understand the amount of rice diversity (the number of local and modern varieties at both the household and community level) and its distribution (the frequency of households growing each variety); analyse the preferred traits of rare, endangered and locally common farmers' varieties; and develop options for adding benefits to cultivating local landraces. It describes preliminary results on understanding genetic diversity in terms of its value to local communities and the participatory methods used to select landrace parents for PPB. Participatory methods, such as biodiversity fairs, diversity blocks, diversity kits and community biodiversityregisters, were integrated to sensitise the local community to varietal diversity issues, to understand the value of local crop diversity, and to strengthen the roles of farmers and the informal sector in the local crop development process.