Planococcus ficus (Signoret)'un parazitoitleri Anagyrus pseudococci (Girault) (Hymenoptera:Encyrtidae) ve Leptomastix dactylopii Howard (Hymenoptera:Encyrtidae) ile avcısı Nephus kreissli Fürsch&Uygun (coleoptera:Coccinellidae) arasındaki birlik içi avcılık
Abstract
The capacity of egg stage consumption and preference consumption of other stages of Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) by the adult and larval stages of Nephus kreissli Fürsch & Uygun (Coleoptera: Coccinellidae) were examined. It was determined Nephus kreissli, its 1st and 2nd larval stages more preferred the egg stage of Planococcus ficus while its 3rd and 4th larval stages more preferred the 2nd and 3rd nymphal stages and females of prey. The egg consumption of predator increased with increasing of its larval stages. The maximum egg consumption was found in its 4th larval stage while the predator fed on the adult stage of prey between its 3rd and 4th larval stages. Certain biological properties of N. kreissli; such as the developmental, preovipotion, ovipotion and postovipotion periods were also studied which made last in 31.5, 6.7, 51.5 and 8 days respectively. The longevity of female and male individuals were determined as 66.2 and 66.6 days; respectively. It was also observed that a single female laid 2.4 eggs daily but a total of 122.7 eggs throughout its life. Furthermore, the net reproductive power (R0) 45.2903 female/female/generation, hereditary reproductive capability (rm) 0.0680 female/female/day and average fecundity time (T0) 56.0398 days of predator was determined. The intraguild predation interactions between N. kreissli and two parasitoids; Anagyrus pseudococci (Girault) and Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae) was examined. It was also noted that whether the 4th larval and adult stages of N. kreissli fed only by one or both parasitoids. N. kreissli fed within the individuals of P. ficus until they turned to become in mummy form. In addition, it was also determined that the parasitized individuals generally preferred those of the unparasitized individuals. The emerging rates of L. dactylopii and A. pseudococci, from parasitized individuals of P. ficus, were determined as 68.63% and 31.37%; respectively. The competition between two parasites, namely A. pseudococci and L. dactylopii, was also examined simultaneously. The host was parasitized by the both parasitoids on different days, no difference were found between the emerging rate out of the parasitoids or the parasitoids which were parasitized before by winning the competition. Moreover, no difference was found in emergence periods of both parasitoids or the emergence periods of A. pseudococci was found shorter during whole experiments. The effects of three natural enemies within P. ficus populations was examined together, bilateral, or alone but on the other hand, a combination effects of three natural enemies was determined most successful among the experiments in population control of mealybug. All experiments were conducted under the conditions with the temperature was 28°C ± 1, humidty %60 ± 10 and the photoperiod was 16:8 hrs. (light: darkness).