Modeling Demographic Response to Constant Temperature in Hypera postica (Coleoptera: Curculionidae)

Alfalfa weevil, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), is among the most destructive pests of alfalfa, Medicago sativa L., in the world. Survivorship and fecundity schedules of H. postica were investigated to characterize the population growth potential of the weevil at six constant temperatures: 11.5, 14.0, 19.0, 24.0, 29.0, and 31.5°C. Preoviposition period, oviposition period and female longevity significantly decreased with rising temperature within the temperature range tested, At the respective temperatures adult female lived an average of 294.2, 230.2, 163.6, 141.0, 84.10, and 32.9 d, with average lifetime progeny production of 470, 814, 2,209, 3,619, 2,656, and 338 eggs per female, The net reproductive rates (R0) were 86.9, 288.0, 869.7, 1,479.7, 989.8, and 107.8 females per female, respectively. Mean daily fecundity (Mx) was modeled as a function of time by using both Enkegaard and Analytis models. Survivorship data (Ix) of adult females were summarized and compared using the shape and scale parameters of the Weibull frequency distribution model across the temperature range tested. Life table entropy values within the range 14.0–31.5°C (H