经定点调查测定,山楂叶螨在苹果树上的空间分布型为聚集分布,四个方位上的螨量,以南方、东方为最多,同方位上下两层的螨量差异不大。据此,提出山楂叶螨的田间调查方法为:取苹果树5株,从东下或南下方位,每株随机取样5点,每点查10只叶片。 According to the site survey, the spatial distribution patterns of hawthorn spider mites on apple trees were aggregated. The mites on the four orientations were the largest in the south and the east, with little difference in the mites between the upper and lower layers. Accordingly, the field investigation method of hawthorn spider mite was proposed: 5 apple trees were taken from the east or the south, 5 plants were randomly sampled from each plant and 10 leaves were screened.