Accelerating the Transfer of Improved Production Technologies: Controlling African Cassava Mosaic Virus Disease Epidemics in Uganda

Since 1988, epidemics of African cassava mosaic disease (ACMD) caused by a whitefly-transmitted geminivirus have caused severe devastation in Uganda resulting in food shortages and famine in some areas. In order to control the disease and restore food security in the country, appropriate technologies had to be developed and transferred quickly to farmers. A diagnostic survey was undertaken in areas severely affected by ACMD in order to understand farmers' knowledge and practices for controlling the disease. Results showed that farmers are aware of ACMD and use what they consider to be resistant varieties, select healthy planting material, rogue infected plants and change varieties in attempts at control. This information was used to develop control measures. Improved genotypes TMS 30572, TMS 60142 and TMS 30337 were compared with the local ones in multilocational and on-farm trials. The three genotypes proved superior and acceptable according to farmers' selection criteria and were released as Migyera, Nase 1 and Nase 2, respectively. A national network of cassava workers (NANEC) was created to address the problem of technology transfer. An integrated strategy for the multiplication and distribution of ‘clean' virus-free stocks of the improved varieties was developed and used by NANEC. Three approaches were used for multiplication:- at institutional farms, by farming groups and by individual farmers. By 1993, 466 ha of the improved varieties were available to supply cuttings that were distributed to farmers in 26 districts seriously affected by ACMD. The advantages and disadvantages of each multiplication strategy are discussed. It is concluded that indigenous knowledge must be acquired and utilized in order to accelerate transfer of agricultural production technologies. The value of such new technologies must be tested in different agroecological conditions and farmers' circumstances, and the best technologies selected based on farmers' criteria and priorities. Moreover, obstacles to adoption must be identified and overcome.

Keywords
Cassava, African cassava mosaic virus disease, control measures, farmers' indigenous knowledge, on-farm trials, technology transfer, propagation/distribution, virus-resistant varieties