Farm-level Evaluation of Monocropping and Intercropping Impacts and Maize yields and Returns in Iganga District-Uganda

Abstract

During the 1997-99 period of IPM CRSP on-farm trials in Iganga district, it was determined that grain yield of maize was higher for Longe 1 variety than the local maize irrespective of cropping system. Grain yield was higher in the monoculture system than in intercropping with beans irrespective of maize variety. Stalkborers and maize streak virus were the main pest and disease respectively which caused maize grain yield losses which were, on average, higher for the local than the improved variety in monoculture. Intercropping with beans had an insignificant retarding effect on stalkborer and streak virus damage on maize. In biophysical terms, therefore, the recommendation would be to grow Longe 1 maize in monoculture. The economic component of the study sought to determine the relative economic benefit of growing Longe 1 maize compared to the local variety and the optimal mix of maize and beans in monoculture. Partial budget analysis and linear programming were used. Data on differences in grain yields, yield losses, farm input quantities, resource limitations and corresponding returns associated with the various field trials were collected. Important links existed between biophysical indicators and economic indicators. Even in terms of economics, in the absence of risk considerations, the adoption of the Longe 1 maize variety in monoculture would be the approach of choice because it could increase maize yields and ensure supply for both farm household food needs and cash income. If the small-holder farmers in the trial area grew Longe 1 maize and beans as sole crops in a season, the optimal combination would be 0.5 ha maize and 0.24 ha beans. The analytical framework outlined in this study that links partial budget analysis to farm enterprise mix optimization should prove useful for future farm level evaluation of cropping systems.




Key words: Crop variety, enterprise mix optimization, objective and subjective strategies, partial budget, stalkborer, streakvirus,.




Eastern Africa Journal of Rural Development (2001) 17, 18-24