Simulation model of brown planthoppers, Nilaparvata lugens stal. (Homoptera: Delphacidae)

Abstract

Brown planthoppers (BPH) were reared on TN1 rice variety in an artificial climate incubator at temperatures of 20, 25 and 30 degrees Celsius. The time to complete life cycle was shorter at lower temperatures and longer at higher temperatures. At temperatures of20 and 25°C, eggs hatched at ranges of 14-19 and 7-8 days, respectively. The duration of development of all immature and mature stages (nymph and adult) in any temperatureregime was not different. The thermal constant for the stage from egg to adult was 356.40 degree days. Population dynamics of brown planthoppers (BPH) were simulated based on insect life cycle and weather data. The computer model followed the state-variable approach by using thermal requirements of each insect stage as driving variables. Then, stages and numbers of insect were predicted. Simulated nymphs and adults of BPH were compared with survey data from the field. The model had reasonable predictive value (70.70%). Timely forecasting of BPH population may help farmers in their decision-making processes. Simulation using future weather can also predict the influence of weather on population dynamics of BPH.