Abstract:
Cowpea is one of the most important legume food crops in Uganda. However, grain yields as low as 400kg ha−1 have been recorded in farmers’ fields despite a grain yield potential of 3,000kg ha−1. Cowpea scab is a major production constraint, causing yield losses of up to 100%. The main interest of this study was to contribute to the management of cowpea scab disease in farmer’s field so as to enhance sustainable production of cowpea towards food security and poverty alleviation among the resource poor and small holder farmers in Uganda. It is on this account that a study was conducted for two seasons (2022B and 202BB) to test the efficacy of a new fungicide, Sulpow to determine its efficacy in controlling scab disease in cowpeas.
Experiments were set in a randomized complete block design with three replications and five treatments (Sulpow 1.5g/L, Sulpow 1g/L, Sulpow 0.5g/L, Ascosulfur (positive check and commonly used fungicide) and Non-treated plots (negative check). The analysis of variance showed significant differences (p < 0.05) for grain yield, scab severity, incidence, and area under disease progress curve (AUDPC) among treatments, seasons, and for treatment by season’s interactions. The meant grain yield of 865.16 kg/ha was recorded across all treatments. Sulpow 1.5g/L was ranked as the best performing with the grain yield of 1766.9 kg/ ha followed by Sulpow 1g/L with grain yield of 1757.9 kg/ha and 18.00g 100- seed weight, Ascosulfur with grain yield of 345.7 kg/ha and 15.82g 00- seed weight, Sulpow 0.5g/L with grain yield of 302kg/ha and 14.73g 100- seed weight while the negative control was the lowest performing with grain yield of 152kg/ha and 14.32g 100 seed weight. The season’s performance was as follows: the grain yield of 853 kg/ha was recorded in the first season and 877.6 kg/ha was recorded in the second season. The highest grain yield of 1746 kg/ha followed by 1730 kg/ha were recorded in Sulpow 1.5g/L and Sulpow 1g/L treatments respectively in the first season while the second season, the highest grain yield of 1787.8 kg/ha and 1785.2 kg/ha were recorded in sulpow 1.5g/L and Sulpow 1g/L treatments. I recommend the use of Sulpow as another fungicide for controlling scab disease of cowpea plants and to make economic sense and avoid wastage, the fungicide should be applied at 1g/L because it performed the same with 1.5g/l and was as well showed a significant difference in its performance with the already existing fungicide (Ascosulfur).
