Flight activity of the lesser grain borer, Rhyzopertha dominica F. (Coleoptera: Bostrichidae), in relation to weather

Abstract

Seasonal flight activity of Rhyzopertha dominica near grain elevators and in forest habitats was monitored weekly in central Oklahoma from 2002 to 2005 using Lindgren four-unit multiple funnel traps baited with the synthetic pheromones Dominicalure-1 and Dominicalure-2. Response surface regression was used to model flight activity (R. dominica trap data) relative to weather variables (temperature, humidity, amount of rainfall, wind speed) and daylength. Overall, the results show more beetle flight activity near grain elevators than in forest sites. Among years, the earliest R. dominica flight activity was recorded from 20 to 27 March, and the yearly flight activity ended between 6 and 13 November. Seasonal flight activity patterns were similar among habitats; however, across years, the flight activity generally initiated at least 1-2 wk earlier in forest than at grain elevator sites in 2 of the 3 yr. R. dominica was most active during the warmer part of the year. No R. dominica were trapped from December through February. Approximately 80 and 86% of the variability in R. dominica trap catches were explained by weekly means of weather variables for grain storage elevators and forest sites, respectively. The weather-based flight activity models for both habitats were validated with independent data. © 2006 Entomological Society of America.