برازش مدل‌های غیرخطی با نرخ ذاتی افزایش جمعیت سوسکCallosobruchus maculatus (Col.: Chrysomelidae) در زمان‌های مختلف تابش مایکروویو

Cowpea seed beetle, Callosobruchus maculatus (F.), is considered as one of the most important pests of stored legumes worldwide. In the last decades, fumigation has been the most effective management tool for control of this pest. Since injudicious applications of these chemicals in the stored products has several restrictions, explorations for reliable control methods such as physical tactics (extreme temperatures, vacuum, Co2 and irradiation) are urgently needed. In the present study, effects of different exposure times to microwave radiation (0, 10, 30, 50, 70, 90, 130 and 170 seconds) on biological traits of C. maculatus were investigated at laboratory conditions with temperature of 25 ± 1°C, relative humidity of 65 ± 5% and a photoperiod of 16L: 8D h. Data analysis was performed according to the age-stage two sex life table theory. Our results confirmed that radiations had significant effects on intrinsic rate of increase (r). In addition, stimulant impact of lower radiation times (up to 130 seconds) on this parameter was noticeable (0.053, 0.055, 0.057, 0.060, 0.076, 0.079, 0.080 and 0.071 day-1, respectively). This evidence revealed that C. maculatus could compensate negative effects of microwave at low radiation times. Furthermore, six non-linear models (Holling Type III, Lactin-1, Logan-10, Polynomial, Pradhan-Taylor and Stinner) were fitted to describe potential of population increase of C. maculatus as a function of radiation time. Regarding the calculated value of R2adj, SSE and AIC coefficients, the Polynomial was found to be the best for modeling intrinsic rate of increase and Holling Type III had the lower fit (Holling Type III: R2adj = 0.803, SSE = 0.00015, AIC = -82.835; Lactin-1: R2adj = 0.909, SSE = 0.00007, AIC = -88.985; Logan-10: R2adj = 0.906, SSE = 0.00007, AIC = -88.734; Polynomial: R2adj = 0.934, SSE = 0.00005, AIC = -91.624; Pradhan-Taylor: R2adj = 0.894 , SSE = 0.00008, AIC = -87.775 and Stinner: R2adj = 0.916, SSE = 0.00006, AIC = -89.645). According to the Polynomial simulations, intrinsic rate of increase of C. maculatus will reach zero at 228 seconds of radiation. This time for the Logan-10 and Lactin-1 models was calculated as 238 and 224 seconds, respectively. Other models could not predict this critical time. These observations underline the importance of considering the role of microwave in management programs of C. maculatus and can be used for further assessment of radiation as a method for controlling stored product pests.