Study On Cold Hardiness Of Sclerodermus Pupariae Yang Et Yao And Its Parasitism On Melanophila Picta Pallas

Karamayis a typical desert oasis city, whose ecological stability is relatively fragile and poor. Enhancing the ecological stability has been an important subject of the economic construction and social development in Karamay agricultural development zone. In this paper, to research the comprehensive control of main trunk pests in Karama, the hardiness of Sclewdermus pupariae Yang et Yao and the Parasitism of Melanophila picta Pallas were studied.1.The flight capacity of Melanophila picta Pallas and the influences of gender and light on it were studied by using the flight mill for the first time in China in this paper. The results showed that Melanophila picta Pallas had strong flight capacity. And the flight capacity was much stronger in the white light than in the dark.2. Supercooling points and freezing points of Sclerodermus pupariae Yang et Yao, Sclerodermus harmandi Buysson and Sclerodermus sp.2 were determined in this study. The results showed that supercooling points of these three species of Parasitoids were different, and there were also differences of different degrees among individuals of the same species. The mean supercooling point of Sclerodermus pupariae Yang et Yao were was-24.81℃ and the mean freezing point was -23.20℃. The mean supercooling point of Sclerodermus harmandi Buysson was -25.48℃ and the mean freezing point was -23.99℃. The mean supercooling point of Sclerodermus sp.2 was -25.81℃ and the mean freezing point was-24.49℃. It was presented that the cold hardiness of the three species of Parasitoids was great, which has important significance for pest prediction and control of Melanophila picta Pallas.3.The parasitism of Sclerodermus pupariae Yang et Yao on Melanophila picta Pallas was measured at different host instar conditions, whose aim was to master the key time for controlling Melanophila picta Pallas using Sclerodermus pupariae Yang et Yao in Karamay district. The results showed significant differences between parasitic rate of the second and third instar larvaes of Melanophila picta Pallas and parasitic rate of the first instar and overwintering larvaes, which indicted the second and third instars were the key time for controlling Melanophila picta Pallas. Sampling fields outdoors with the same damage degree of Melanophila picta Pallas were selected as well, at the different sections, with a distance of more than 100 meters to each other, in which 500,1000, and 2000 Sclewdermus pupariae Yang et Yao were respectively placed per mu. It was presented that with the increase of Sclerodermus pupariae Yang et Yao the parasitism of Melanophila picta Pallas was higher. In addtion, Sclerodermus pupariae Yang et Yao was found in the sampling fields the next year, which showed the introduction of Sclerodermus pupariae Yang et Yao for Melanophila picta Pallas control in Karamay has great extend value.