Model selection and averaging in the estimation of population parameters of Bemisia tabaci (Gennadius) from stage frequency data in sweet pepper plants

Abstract

Bemisia tabaci is a significant pest for many crops, but there are few population studies of this insect on sweet pepper (Capsicum annuum). In this study, stage frequency data were generated with B. tabaci in sweet pepper plants in various situations, and the Bellows and Birley method was used to obtain population parameters from the data. The Akaike Information Criterion (AIC) was used to select the best option of the Bellows and Birley method and, in some cases, to estimate the parameters of the population using model averaging. The ratios estimated/observed for each population parameter were calculated to assess bias and were used to correct the estimations if the ratios were different from 1. The effects of different factors on the estimations of population parameters were analysed. The total duration of development was affected by the experimental conditions (laboratory vs. greenhouse) and temperature, but it had the highest precision. The final survival rate was affected by temperature, and the estimation of individuals entering each stage was affected only by the options included in the Bellows and Birley method. AIC helped to detect differences in the daily survival rate among the different experiments between N1 (first instar) (range 0.842–0.923), and the egg (range 0.989–1.0) and N4 (fourth instar) (0.990). The methodology used can be employed in field population studies. For example, the final survival rate in the greenhouse experiments varied between 0.624 and 0.097, depending on if the parasitoids were present or not, and the total development varied between 420.6 and 440.7 degree days.