Impact of irradiation on some biological aspects of the mite Tyrophagus putrescentiae (Schrank), (Acari: Acaridae)

The effect of 50, 100, 150 and 200Gy on some biological aspects of newly emerged Tyrophagus putrescentiae adults (male and female) were studied. 4 different mating crosses were placed “1-irradiated ♀ X normal (unirradiated) ♂, 2-irradiated ♂ Χ normal ♀, 3-both were irradiated and 4-both were normal as control”. Results revealed that increasing gamma radiation led to increase the longevity of irradiated male or female. In contrast, the raise of radiation doses resulted in negative relationship in the hatchability percentage of eggs. Consequently, the sterility in the 3 mating models was in parallel to the radiation dose raise, since there was no any hatchability in 150 and 200 Gy in comparing with the control. Furthermore, the irradiation of one or both parents caused elongation in egg incubation period, life cycle and life span periods of the produced generation (F1). The results were more obvious in the group of both males and females were irradiated, than when only one of them was irradiated. In addition, when examine the susceptibility different eggs ages’ (0-12h., 12-24h., 24-36h and 36-48h.) were irradiated with the same doses, the results exposed that the oldest eggs were the most resistant to gamma rays than the other ages that recorded the higher percentages of hatchability Generally, gamma radiation affects the production and progeny of T. putrescentiae. Finished to, that applying a dose of 50 Gy on one of couple (male or female) before mating; or on both of them, was enough to control it and could be used as an ecofriendly control tool in stores.