Seasonal effects on potato production under conventional and small seed plot technologies in the Mt. Elgon zone

Abstract

Potato production in the Mt. Elgon zone of Uganda is constrained by seasonal variations, lack of clean seed and the challenges of pests and diseases. Consequently, yield hardly exceeds 2.9 t ha-1 yet a potential of 10 t ha-1 can be realised. This study was conducted to determine the effect of seasons and the small seed plot technology in enhancing seed potato production in the Mt. Elgon zone. On-farm trials were conducted in Bududa, Sironko, Manafwa, Kapchorwa and Kween districts in the first and second seasons of 2011. Results showed higher potato yield in Kapchorwa and Kween in the second season compared to the other districts. However, Bududa district has potential to achieve relatively higher potato yield in both seasons. Number of tubers were more in small seed plots than conventional potato planting with significant effects (P < 0.05) in Bududa and Kapchorwa. Number of tubers with bacterial wilt were higher in conventional potato planting than the small seed plots, with Manafwa and Sironko registering the highest incidence. Though bacterial wilt and late blight incidence was not significantly different in the two seasons, infected tubers for both pathogens were more in Manafwa and Sironko for bacterial wilt, and Bududa and Kapchorwa for late blight. Principal component analysis revealed that tuber numbers and potato tuber moth damage was more associated with environment in Kween. The results demonstrated that potato productivity in the Mt. Elgon zone is higher in the second season, with the small seed plot technology being favourable for small land holdings than conventional potato planting.