Objective 1: Characterize the vulnerability of rice to MRB as a function of plant age/stage in three inbred varieties.Objective 1a. Characterize the relationship between rice plant age/stage on susceptibility to oviposition preference in three rice varieties.Objective 1b. Characterize the relationship between rice plant age/stage on susceptibility to losses in grain yield in three rice varieties.Objective 2: Develop new specialized rice phenology model to predict the timing of rice stages most vulnerable to MRB and verify the effectiveness of the model.Objective 2a. Develop specialized rice phenology model to predict the timing of vulnerable ontogenetic stages to MRB in three inbred varieties using data generated in Objective 1.Objective 2b. Assess the efficacy of the model by using it to time applications of foliar insecticides against MRB in field plots of rice.Objective 3: Characterize the relationship between incidence of MRB (deadhearts and whiteheads) and yield loss at a range of panicle densities in three inbred rice varieties.Objective 4: Develop decision tools for management of MRB including an online scouting guide and yield loss calculator.