The response of two legume crops (hyacinth bean and Kidney bean) to the parasitism of field dodder (Cuscuta campestris)

Microscopic examinations and chemical studies were performed to study the response of two legume crops, hyacinth bean ( Lablab purpureus L. ) Sweet and kidney bean ( phaseolus vulgaris L. ) to the filed dodder (FD) ( Cuscuta campestris Yuncker ) parasitism. Hyacinth bean, showing no effective resistance mechanisms,was found to be a highly susceptible host to FD. However, kidney bean, displaying resistant reactions towards the parasitism of FD,was found to be an incompatible host.The possible reasons for the resistance of kidney bean to FD were anatomical (hypersensitivity) and chemical (high contents of phenolic acids and lignin) stimulated defence mechanisms, which developed during the actual intrusion of FD haustorial cells inside its tissues.