Inheritance of resistance to Fusarium wilt in some sesame crosses under field conditions

Lines of two generations (F3 and F4) from 15 crosses were screened for two successive seasons (2004 and 2005) for their reaction to Fusarium wilt disease under natural infection by Fusarium oxysporum f.sp. sesami. There was sufficient variability among all crosses and some lines could be valuable for further breeding programs for wilt disease resistance. Offspring of the crosses P1 × P6, P2 × P4 and P3 × P6 seem to be stable in their reaction to the disease in the years of evaluation, though with some segregation from one generation to another. The crosses P1 × P5, P2 × P6, P3 × P4 and P3 × P6 showed a resistant reaction through both generations as well as both seasons. They might be helpful and utilised for large scale cultivation or/and in hybridisation programs to develop resistant varieties with good yield potential. Heritability estimates were very high (more than 95%) in both generations during the two seasons, except for seed yield/plant in the F3 in the first season. This indicated that selection for both Fusarium wilt resistance and seed yield from these lines could be feasible and lead to resistant cultivars with seed yield potential. The results showed highly significant and positive correlations between lower infection in the F4's and in F3's through the two seasons. The highest significant correlation of the evaluated traits allowed the selection of some lines to be used in breeding programs. Also, highly significant positive correlations were detected between seed yield/plot of the F4's in 2004 and the seed yield/plot of F4's in 2005, but did not reach the significant level in the F3's.