Development and life table parameters of the Phytoseius corniger Wainstein (Acari: Phytoseiidae) feeding on the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions

Abstract

Phytoseiid mites are important for biological control of some pest species including phytophagous mites and small insects. The species, Phytoseius corniger Wainstein is one of the most abundant predatory mite in fruit orchards and urban green spaces in Razavi Khorasan province, Iran. Biological parameters of this predatory feeding on the two-spotted spider mite Tetranychus urticae Koch was studied for the first time under the laboratory conditions (25±2 ºC, 55±5 % RH and 16L: 8D photoperiod). The results indicated that the mean developmental periods for egg, larva, protonymph and deutonymph were 1.12±0.09, 0.73±0.03, 1.01±0.03, and 3.05±0.09 days for females, and 0.95±0.37, 0.67±0.39, 1.05±0.88, and 3.05±0.85 days for males, respectively. The pre-oviposition, oviposition, post-oviposition periods and adult longevity for females were 4.63±0.11, 11.63±0.16, 7.93±0.13 and 24.18±0.21 days, respectively. The females laid an average of 0.48 eggs per day, and 5.60 eggs during their life span. In addition, larvae of P. corniger may molt to the protonymph stage without feeding. Consumption rate during nymphal stage was 1.95 prey per day. The highest rate of prey consumption was recorded during the oviposition period, with an average of 3.35 prey items prey per day. Regarding life-history traits, the intrinsic rates of increase (rm) of this predatory mite 0.064±0.02 (♀♀/♀/day) and its finite rate of increase (λ), net reproduction rate (R0), generation time (T), and doubling time (DT) were 1.066±0.23 (day-1), 3±0.07 (♀♀/♀/generation), 17.14±0.11 (days), and 10.83±0.65 (days), respectively. Further laboratory and field studies regarding its diet preference and predation capacity are needed.