Modelling development time of Myzus persicae (Hemiptera : Aphididae) at constant and natural temperatures

Abstract

The development period from birth to adult of alate and apterous virginoparae of the green peach aphid, Myzus persicae (Sulzer), reared on Brassica campestrisssp. chinensis, was measured at 13 constant and five natural temperature regimes. The day–degree model, the logistic equation, and the Wang model were used to describe the relationships between temperature and development rate at constant conditions. The constant temperature–development curves derived from the three models were used with a Weibull function describing the distribution of development times, to simulate the development of individuals of cohorts reared at natural temperature regimes. Comparison of the observed with simulated distributions of adult emergence indicates that all three models can simulate the development of M. persicaevery well when the temperature does not go below 4°C, the notional low temperature threshold of the day–degree model. When accumulation of temperatures below 4°C becomes substantial, only the logistic curve with a low temperature threshold of 0°C can offer accurate simulations; the other two models give falsely longer durations of development. Methods for accurately simulating the development of M. persicae in the field are suggested. The significance of modelling insect development at low temperatures by nonlinear models is discussed.