Characterizing variation in resistance among commonly grown rice cultivars in Louisiana against sugarcane borer, Diatraea saccharalis

Rice is grown over an area of approximately 455,000 acres in Louisiana. The stem borer complex attacking rice in the Southern U.S includes stalk borer, Chilo plejadellus, sugarcane borer (SCB) Diatraea saccharalis, and Mexican rice borer, Eoreuma loftini (Dyar). With the increasing impact of stem borers on rice production and the arrival of Mexican rice borer in Louisiana, an urgent need exists to develop strategies for managing borers that includes multiple tactics such a plant resistance and chemical control. Currently, no IPM program is in place for SCB in Louisiana rice. The primary goal of this study is to develop an IPM program for SCB. Greenhouse and lab studies were undertaken to characterize variation in resistance among commonly grown cultivars in Louisiana that may help in development of resistant varieties. In these experiments, compensation, larval weight gains and boring success of larvae in eight commonly grown cultivars were studied. Results revealed significant differences among varieties for these three parameters. The hybrid XL723, Clearfield varieties and the medium grain Bengal showed lower larval weight gains and boring success than Priscilla, Cocodrie, Cheniere and Jazzman. In the compensation experiments, infested plants produced more number of tillers and more seeds per panicle as compared to the control plants and also there were differences among varieties for compensation.