Fitness Enhancement by Crosses between Two Populations of Trissolcus vassilievi (Hymenoptera: Scelionidae)

Trissolcus vassilievi (Mayr) (Hymenoptera: Scelionidae) is one of the most important egg parasitoids of the Common Sunn Pest (CSP), Eurygaster integriceps Puton (Hemiptera: Scutelleridae) in Iran. In this study, the fitness of two populations of T. vassilievi was studied on two populations of hosts in terms of life history parameters. Two populations of both T. vassilievi and the host, CSP were selected: (۱) Tabriz (as a temperate area), and (۲) Varamin (as a subtropical area), for CSP. Moreover, regarding that outcrossing between populations can produce progeny with superior characteristics, the progeny of reciprocal crosses between original populations also were examined on a single host. The crosses between the two populations caused ۱۳.۹-۱۸.۵% higher net fecundity than maternal populations, which suggests fecundity to be a function of maternal phenotype. The intrinsic rate of increase showed minor differences among treatments, which varied between ۰.۲۹۱±۰.۰۰۳ to ۰.۳۰۵±۰.۰۰۳. The partial advantage of Varamin wasps over Tabriz, and the crosses over the original populations was obvious. Such differences may be used to obtain more efficient parasitoids in augmentation programs.

کلیدواژه ها:

Intrinsic rate of increase ، Life expectancy ، Net reproduction rate ، Parasitoid wasp ، Reciprocal crosses