Abstract:

It was studied that the biology, effective accumulate temperature and population dynamics of Euteranychus orientalis. The results showed that in 18～30℃, the development duration decreased and the development rate increased with temperature increasing; in 22.5～27.5℃, the life-span of female adult mite was 8～10 d and the life-span of the male adult was 4～6 d. The females have significant behavior of “protecting their eggs". The development zero(C), effective accumulate temperature (K) and generation number in a year were calculated by least square method, linear regression method, least variation coefficient method and directed optimization method. Results of the four methods had no significant different. Amount of the mite appeared 2 peaks in a year. The first peak was from the last ten-day period of May to the middle ten-day period of June; the second peak was from the middle ten-day period to the last ten_day of September. In the first peak the amount of the mite appeared largely and injuring was serious.

Key words: Eutetranychus orientalis, biological characteristics, habit of &ldquo, protecting eggs", effective accumulate temperature