The maternal effect of temperature on diapause induction in Wolbachia-infected and uninfected Trichogramma brassicae

In present study, the maternal effect of temperature as an ecologic factor and the effect of Wolbachia infection as an inner-genetic factor on diapause percentage of Trichogramma brassicae Bezdenko (Hym.: Trichogrammatidae) were investigated. Maternal generation of both infected (asexual) and uninfected (sexual) populations were reared separately at 14 and 20°C. After maximum adult emergence (24 hours), asexual females and sexual-mated females (both 24h old) were separately selected and placed in glass test tubes. Each of them were supplied with a cardboard which included 100 eggs of Ephestia kuehniella Zeller (Lep.: Pyralidae) (6 hours old). The results revealed that Wolbachia infection and rearing temperature of maternal generation had significant effect on diapause percentage of T. brassicae. When rearing temperature increased, the diapause percentage had increased too. Diapause percentage in uninfected (sexual) population was higher than infected (asexual) ones which show the negative effect of Wolbachia infection. Probably, presence of Wolbachia causes energy reduction in facing low temperature.