川北地区花生蛴螬的发生和防治

川北地区花生蛴螬以暗黑齿爪鳃金龟为优势种群，占蛴螬总虫量的８４．４％，平均果荚被害率２０％以上。蛴螬在花生地呈聚集分布型。越冬蛴螬化蛹盛期为４月中旬至５月下旬，５月中旬至６月上旬为羽化盛期，田间卵盛期出现在６月下旬至７月上旬末，低龄蛴螬发生在７月份。发生轻重与土壤质地，花生播期和７月上中旬降雨量，连续降雨日数密切相关。

THE OCCURANCE AND CONTROL OF PEANUT WHITE GRUB IN THE NORTH OF SICHUAN PROVINCE

Among the peanut white grubs in the northern part of Sichuan, Holotrichia morosa Watcrhous is the dominant population, which accounts for 84.4% of the total white grubs. And the percentage of the affected fruit hulls reaches over 20%. The white grubs present an aggregate distribution in the peanut fields. The period from the second ten days of April to the last ten days of May is the full pupation stage for overwintering white grubs, and the period from the second ten days of May to the first ten days of June is the full feathering stage. The full ovulation in the field occurs during the last ten days of June to the late first ten days of July. Early instar grubs appear during the first to the last days of July. The degree of occurance is closely related with the soil quality, the sowing time of peanut, the rainfall in the first and second ten days of July and the continuous rainy days. The effective measures to control white grubs are to adjust sowing time, catch imagoes by hand and use pestcide at and approprate time.