Inheritance of resistance to Fusarium wilt and yield traits in pigeonpea

Fusarium wilt is the main pigeonpea production constraint in Malawi. The purpose of the study was to understand the nature and mechanism of inheritance of F. wilt resistance, yield and secondary traits in pigeonpea. 48 crosses were generated in a 12 lines x 4 testers mating scheme. Some F-1 plants were selfed for segregation analysis for inheritance pattern of resistance, while others were evaluated for resistance, yield and secondary traits. There were significant variations among F-1 plants for F. wilt, days to 50 % flowering, seed/pod, and number of secondary branches. Specific combining ability (SCA) effects were predominant for F. wilt, days to 50 % flowering and number of secondary branches. The general combining ability (GCA) effects, mainly due to maternal genotypes, were preponderant for yield and other secondary traits. The significance of GCA and SCA effects suggested that variations were due to additive gene action in both the testers and parental lines arising from their interactions, and the dominance effects due to interactions of the parental lines. The chi(2) analysis suggested dominant patterns of inheritance for wilt in most of the F-2 populations. The segregation ratios of 3:1, 15:1, and 9:7 suggested the involvement of single or two independent/complementary dominant genes in the test donors. Involvement of a few genes governing wilt resistance suggested the ease of breeding for this trait. Pedigree breeding method would be recommended for incorporating various traits in pigeonpea.