INFLUENCE OF CERTAIN PREY TYPES ON SOME BIOLOGICAL CHARACTERISTICS OF Chrysoperla carnea (STEPH.) UNDER CONSTANT TEMPERATURE AND RELATIVE HUMIDITY.

Abstract

Laboratory experiments were carried out in Economic Entomology Department, Faculty of Agriculture , Mansoura University under constant temperature of 28 ± 2° c and relative humidity of 70 ± 5 % to investigate the influence of some prey types on certain biological aspects of Chrysoperla carnea (Steph.) . These prey types were Aphis gossypii Glover, Macrosiphum rosae (L.), Aphis nerii Boyer and Gynikothrips ficorum Marchal . The obtained results indicated that the shortest developmental time was obtained when the larvae of C. carnea reared on M. rosae (12.07±0.53days), while the longest developmental time was recorded when the larvae of this predator fed on A. gossypii ( 15.46 ± 0.8 days ). The results showed that, the numbers of the insect species as prey consumed by a predator larval stage varied according to insect species as it averaged 194.20± 9.75; 129.28±7.56; 80.58± 4.78 and 132.33±8.42 individuals when fed on A. gossypii; M. rosae ;A. nerii and G. ficorum, respectively. The data cleared that, the second and third larval instar were the most efficient in predation. The variation in the prey typs also showed difference in the duration of the larval stage as it averaged 15.46 ± 0.86; 12.07± 0.53; 12.8±0.85 and 11.74 ±1.86 days for previously mentioned species, respectively. Female fecundity also varied from 423.2±7.86; 340.20 ± 5.32; 188.40±2.46 and 423.2±8.42 eggs for A. gossypii ; M. rosae ; A. nerii and G. ficorum, respectively. The obtained results assured the effect of prey kinds on the developmental time, consumpation rate of larval stage and the longevity of male and longevity and fecundity of C. carnea female. The highest number of eggs obtained when the females (which their larvae) reared on G. ficorum , while the lowest number of eggs were achieved when they reared on A. nerii .