Predicting the population growth potential of Bactrocera zonata (Saunders) (Diptera: Tephritidae) using temperature development growth models and their validation in fluctuating temperature condition

Bactrocera zonata (Saunders), a serious polyphagous pest of horticultural crops, was studied for temperature based growth potential at ecologically relevant constant temperatures (15, 20, 25, 30 and 35 °C; relative humidity of 60 ± 10% and a photoperiod of 12:12 h L:D) and simulated growth potential parameters were validated with fluctuating temperatures life cycle data under laboratory conditions on artificial diet. Rate summation and cohort updating approaches were used for simulating development and estimating life-table parameters of B. zonata. The results revealed that lower development thresholds as 11.9, 12.7, and 13.6 °C and optimum temperature for survival as 26.01 °C, 26.2 °C and 25.5 °C determined for eggs, larvae and pupae, respectively. Reduction in mean development time of all immature stages occurred with increase in temperature. The highest net reproductive rate (77.64 ± 2.59 females/female/generation), total fecundity (260.20 ± 6.37 individuals/female/generation), intrinsic rate of increase (0.10 ± 0.000 females/female/day) and finite rate of increase (1.10 ± 0.000 females/female/day) were obtained maximum at 30 °C. At lowest extreme temperature (15 °C) tested in present study, females were not able to lay eggs. The temperature between 25 and 28 °C was the most suitable range for B. zonata reproduction and development. This shows that temperature has significant role in determining the climatic suitability for B. zonata in reproduction.