›› 2009, Vol. 52 ›› Issue (6): 640-650.

• RESEARCH PAPERS •

### Estimating developmental rates of Helicoverpa armigera (Lepidoptera: Noctuidae) pupae at constant and alternating temperatures by nonlinear models

• Online:2009-06-20 Published:2009-06-20

Abstract: Developmental durations (d) of Helicoverpa armigera (Hübner) pupae were determined at constant temperatures from 15 to 37℃ and alternating temperatures from 12/18 to 34/40℃ for comprehensive analyses on insect development in relation to temperature. Both linear model and nonlinear models (Logan model, Lactin model and Wang model) were used to fit the observed data, and these nonlinear models gave a more accurate description of temperature-dependent developmental rates with the coefficients of determination (R2) ranging from 0.9878 to 0.9991. Further fitting various numbers of the observed data showed that so long as six cases of them distributed in the proper way， these nonlinear models could estimate pupal developmental rate with high satisfaction. On the other hand， lack of the data at high temperature would give a false prediction. A possible cause for difference between developmental rates of the pupae at constant and alternating temperatures is illustrated. The strong and weak points of the three nonlinear models when applied to estimate the pupal developmental rate are commented. The results suggest that the nonlinear models may be of significant value in improving prediction of insect pest occurrence as well as rearing and management of beneficial insects as alternative to linear degree-day model.