David E. Bragg, braggd@wsu.edu1, Patricia A. Carr, murphyp@wsu.edu, Kurt Tetrick, cffarm@hughes.net2, and Diana Elizabeth Roberts, robertsd@wsu.edu3. (1) Washington State University, Extension Entomology, P O Box 190, Pomeroy, WA, (2) USDA ARS, Plant Introduction Center, 639 Hastings Hill Rd, Pomeroy, WA, (3) Washington State University, Extension Agronomy, 222 N Havana, Spokane, WA
Studies of Cereal Leaf Beetle adult and larval feeding were conducted in the spring of 2007. Winter and spring wheat varieties were seeded adjacent to an established field insectary located at Central Ferry WA. The adult beetles emerged and began feeding on winter wheat in late April. Egg deposition began at this time and continued to the early flag leaf stage in mid June. Parasitoidism by T. julius was 0% May 24, 38% June 4, and 93% June 14. Ladybird beetles were active predators of eggs and small CLB larvae. The CLB adults from this generation moved to the spring wheat trial by June 20. Ladybird beetle and parasitoid activity continued to hold the population of CLB to 20% infested tillers in the spring wheat. Flag leaf damage studies were made to evaluate economic threshold.
Species 1: Coleoptera Chrysomelidae
Oulema melanoplus (cereal leaf beetle)
Species 2: Coleoptera Coccinellidae
Hippodamia convergens (convergent ladybird beetle)
Species 3: Hymenoptera Eulophidae
Tetrastichus julis (cereal leaf beetle parasitoid)