D3080: Finding rice varietal resistance to rice water weevil and fall armyworm

Texas rice production is threatened by many insect pests. Historically, the most destructive of these is the rice water weevil, Lissorhoptrus oryzophilus. An occasional pest is the fall armyworm, Spodoptera frugiperda. Both pests are generally managed by insecticides which can cause adverse effects on the environment. The goal of this study is to identify varieties with natural resistance to these insect pests by assessing differences in pest density, larval growth, and plant growth. Field experiments were conducted in Beaumont and Eagle Lake, Texas and established according to a randomized block design. Five commonly grown rice varieties in Texas were planted in the field and were either treated with chlorantraniliprole seed treatment or untreated plants. Weevil density and plant growth of each treatment/variety will be assessed once per week for three weeks, starting three weeks after flooding. A greenhouse experiment with the same varieties, all untreated, will be infested with fall armyworm larvae. After one week, plant response and larval growth will be assessed. Expected results are that treated plants in the field will have lower weevil densities and more favorable plant response compared to untreated varieties, and certain untreated varieties will perform better than others. It is expected the varieties that performed best in the field will perform best in greenhouse conditions. This study will further our knowledge on varietal resistance to insect stress and allow us to work with plant breeders to develop resistant varieties to these pests.