Abstract
The response of six groundnut cultivars to fungicidal control of leaf spots was examined at three different locations in 1987 and 1988 crop seasons in Niger. In 1987, leaf spots were not severe at Sadore and Maradi due to low rainfall conditions and the fungicidal control of these diseases resulted in only a marginal increase in pod (5%) and haulm (10%) yields. However, in 1988 leaf spots were severe, causing almost 100% defoliation and control of these diseases substantially increased the yields, at Sadore by 48% in pod yield and 53% in haulm yield, and at Maradi by 24% in pod yield and 21 % in haulm yields. In Bengou, leaf spots were destructive in both years and fungicidal control markedly increased the yields of pods by 44% in 1987 and 67% in 1988 and haulms by 31% in 1987 and 62% in 1988. Some cultivars responded more to leaf spot control than others and the response varied considerably between locations and years, suggesting that specific genotype × environment × disease interaction may have occurred. The cultivars ICGV 87123 (formerly ICGS 11) and 796 consistently out-yielded all other cultivars in both years and spray treatments at Bengou and Maradi, respectively.
