Variable Resistance to Homopterans in Rice Cultivars

Rice-breeding programs in Asia have successfully provided farmers with cultivars that have genetic resistance to the major insect pests, including the leafhoppers and planthoppers. The widespread planting of resistant cultivars has resulted in the selection of hopper populations that have overcome the resistance factor(s) in the plant. Procedures to measure the degree and rate of selection for virulence on resistant cultivars have been developed, and rice-breeding strategies to increase the stability of hopper-resistant cultivars have been implemented. Resistant cultivars have been widely and successfully used in Asia and Central and South America in the management of certain rice homopterans. Rice-breeding lines with resistance to additional homopteran species are in the pipeline. To most successfully utilize the diversity of insect-resistant germplasm requires novel rice-breeding techniques and the integration of the resistant cultivars into rice insect management programs so as to provide an increased level of stability