Impact of a new source of resistance to fusarium wilt in pigeonpea

Pigeonpea is an important grain legume grown by smallholder farmers in Southern Africa. Fusarium wilt, caused by the fungal pathogen Fusarium udum Butler, is the major disease limiting pigeonpea production in the region. This study was designed to evaluate the reaction to fusarium wilt as well as agronomic performance of new elite pigeonpea germplasm in three different countries during the 2001/2002 cropping season using wilt-sick plots. Per cent incidence of fusarium wilt (%FW), grain size and yield, were measured. The genotype ICEAP 00040 consistently showed a high (< 20.0%) level of resistance to the disease in all three countries. In contrast, %FW score for the susceptible genotype ICEAP 00068 was 87.5, 92.0 and 90.9% in Kenya, Malawi and Tanzania, respectively. The grain size obtained for ICEAP 00040 at Ngabu (Malawi) was 25.0% larger than that at each of the remaining locations indicating environmental influence on this trait. At all the three locations, >= 1.5 ton/Ha of grain yield was obtained for ICEAP 00040 compared with < 1.0 ton/Ha for ICEAP 00068. In 2003, this improved resistant genotype (ICEAP 00040) was released for commercial production and will be useful as a good source of resistance in pigeonpea genetic improvement programs in the region.