A temperature-dependent phenology model for Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae)

The sweetpotato whitefly, Bemisia tabaci (Gennadius) Middle East-Asia Minor 1 (MEAM1), is widespread across tropical and subtropical regions, affecting hundreds of cultivated and wild plant species. Because the species transmits a variety of viruses, the whitefly has become one of the most economically significant insect pests in the world. Determining a pest's population growth potential as a function of temperature is critical for understanding a species population dynamics, predicting the potential range of the species and its associated diseases, and designing adaptive pest management strategies. The life history of B. tabaci MEAM1 was studied in life-table experiments at 7 constant temperatures ranging from 12 to 35 °C. Nonlinear equations were fitted to development, mortality, and reproduction data and compiled into an overall phenology rate-summation model using Insect Life Cycle Modeling (ILCYM) software, to simulate life-table parameters based on temperature. Life tables of B. tabaci MEAM1 observed at naturally variable temperature in La Molina, Lima, during different seasons, covering the entire temperature range of the species' predicted performance curve, were used to validate the model. Simulations predicted population growth within temperature between 13.9 and 33.4 °C, revealing a maximum finite rate of population increase (λ = 1.163), with a generation time of 33.3 days at 26.4 °C. Predicted species performance agreed well when compared against observed life tables and published data. The process-based physiological model presented here for B. tabaci MEAM1 should prove useful to predict the potential spatial distribution of the species based on temperature and to adjust pest control measures taking different population growth potentials due to prevailing temperature regimes into account.