Reinhardt Howeler, CIAT Regional Office Dept. Ag, Bangkok, 10900, Thailand
In order to enhance the adoption of soil conserving practices and improve the sustainability of cassava production under a wide range of socio-economic and bio-physical conditions, a farmer participatory research (FPR) approach was used to develop not only the most suitable soil conservation practices, but also to test new cassava varieties, fertilization practices and cropping systems that tend to produce greater short-term benefits. The FPR methodology was initially developed in 2-3 sites each in China, Indonesia, Thailand and Vietnam. The methodology includes the conducting of RRAs in each site, farmer evaluation of a wide range of practices shown in demonstration plots, FPR trials with farmer-selected treatments on their own fields, field days with discussions to select the best among the tested practices, scaling-up of selected practices to larger fields, and farmer participatory dissemination to neighbors and neighboring communities. Based on the results of these trials, farmers in the pilot sites have readily adopted better varieties, fertilization and intercropping practices, and many farmers have adopted the planting of contour hedgerows to control erosion. In the second phase of this Nippon Foundation supported project, the farmer participatory approach for technology development and dissemination was further developed in a total of 99 pilot sites in Thailand, Vietnam, and China. The testing by farmers on their own fields of new cassava varieties and fertilization practices in addition to soil conservation practices was found to be of crucial importance for the adoption of more sustainable production practices. The resulting increases in cassava yields over the past ten years have increased the annual gross income of cassava farmers in Asia by an estimated 325 million US dollars.