SUSCEPTIBILITY TO LEAF SILVERING IN THE CULTIVAR GROUPS OF SUMMER SQUASH

Summer squash (Cucurbita pepo) cultivars, three from each of the six c ultivar groups, were grown under field and greenhouse conditions at Fo rt Pierce, Florida, U.S.A. in the presence of sweetpotato whiteflies ( Bemisia tabaci) and observed for severity of leaf silvering. All culti vars were affected by leaf silvering, but some had less severe symptom s than others. The cocozelle group was the least susceptible to silver ing. There appeared to be an association between geographic origin of cultivars and their susceptibility to silvering.