Host Specificity and Resistance of Cowpea and Common Bean to Elsinoë spp. isolated from cowpea

Cowpea, a crucial legume crop in Kenya, suffers from significant yield losses due to scab disease induced by Elsinoe pathogens. This research examined scab under controlled settings, pinpointing the pathogen's identity as Elsinoe, distinct from Elsinoe phaseoli, which affects common bean. By isolating the fungus from infected cowpea plants and using DNA barcoding, scientists confirmed its specificity to cowpea.

Tests demonstrated that cowpea varieties Kunde Tamu and Kunde Soko were highly susceptible, with extensive lesions appearing by flowering and pods turning into mummies in the pod-filling stage. One variety, Kat Kunde, showed partial tolerance, only suffering minor symptoms. In contrast, common bean varieties tested displayed no signs of the disease, confirming the scab pathogen's strict host specificity for cowpea and providing insights into suitable resistant plant material for combating the disease.