The influence of photoperiod on development and population growth performance of the Phytoseiulus persimilis fed on Tetranychus urticae

Environmental factors, such as photoperiod, can play an important role in the development of mites. The influence of photoperiod (L:D = 4:20, 8:16, 12:12, 16:8 and 20:4) on the development and population parameters of the predatory mite, Phytoseiulus persimilis Athias-Henriot fed on two-spotted spider mite, Tetranychus urticae Koch was examined under laboratory conditions. Pre-adult development decreased with increasing photoperiod until 12 h, after which the development period progressively increased. Longevity of both sexes demonstrated significant differences throughout photoperiods, with the longest at 20:4 L:D and the shortest at 8:16 L:D. The highest value of mean total fecundity was 13.62 egg/female at 12:12 L:D photoperiod. The net reproductive rate (R0), the intrinsic rate of increase (r) and the finite rate of increase (lambda), showed the highest value at 12:12 L:D. The R0, r and lambda for P. persimilis increased with increasing photoperiod from 4:20 to 12:12 L:D, but decreased sharply at the 16:8 and 20:4 L:D treatments. Our findings indicate that photoperiod has a significant role in advancing the rate of development, survival rate, and reproduction for commercial production of P. persimilis, with a 12:12 photoperiod length recognized as the ideal period for commercial production in culture.