THE REVIEW OF VARIETAL RESPONSE TO BEAN COMMON MOSAIC POTYVIRUS IN PHASEOLUS-VULGARIS

Bean Common Mosaic Potyvirus is the most serious and wide spread seed borne virus pathogen of common bean. Disease epidemics can be minimize d through cultural practices, and seed certification programmes, but t he only effective control is through the use of genetic resistance. Fi ve independent genes controlling resistance to different strains of th e virus have been identified and their inheritance characterized. Two distinct types of resistance mechanisms are recognized. One type is in duced after virus invasion while the other is constitutive. The develo pment of specific host symptoms after inoculation with the NL 3 strain of bean common mosaic potyvirus indicated which type of resistance me chanism is operating. The opportunity to recognize and combine resista nce mechanisms in common bean is discussed.