BIOLOGY AND PREDATORY POTENTIAL OF COCCINELLA SEPTEMPUNCTATA LINN. ON SCHIZAPHIS GRAMINUM APHID UNDER CONTROLLED CONDITIONS
Maria Rauf*, Ehsan-ul-Haq**, Javed Khan**, Abdul Rehman***, Waseem Ahmad Gillani* and Asrar Ali**
The biology and predatory potential of Coccinella septempunctata (Linn.) were studied on aphid, Schizaphis graminum (Rondani) at three constant temperatures 20±1 °C, 25±1 °C and 30±1 °C in Insectary-Bio Control Laboratories, National Agricultural Research Centre (NARC), Islamabad. The results revealed that incubation period of C. septempunctata was 5.12, 3.62 and 3.20 days with 75.6%, 82.0% and 71.2% hatchability, respectively. The larval durations were 29.5, 15.9 and 8.1 days with predatory potential of 573.7, 575.0 and 667.8 aphids per larvae. The results indicated that with increasing temperature, developmental duration decreases significantly. The pupal developmental duration was 14.0, 9.2 and 5.2 days, respectively which are significantly different from each other. The adult male and female longevity were 44.7, 37.7, 30.0 and 60.3, 58.9 and 43.7 days. Fecundity rate of females were 123.5, 251.5 and 293.2 eggs per female, respectively. This indicates that adult male and female developmental duration, female fecundity rate were significantly different from each other at three constant temperatures. Maximum female and male predatory potential was 3262.8 and 2571.7 aphids at 25 ±1 °C while minimum was 2276.8 and 1890.6 aphids, respectively.