【摘要】 <正> 蛴螬为主要农作物苗期害虫之一,在华北地区发生极广,为害严重,在全国范围内发生亦相当普遍。华北各省如山西、河北、山东、河南及内蒙古自治区,一般大都发生于灌溉地或较潮湿的地区。如据山东 1953年 45县不完全统针,因被害严重而改种的就有一万余亩,诸城县有一万余亩花生,因受害而严重减产。菏泽1951年在18个村调查被害面积,更多还原

【Abstract】 The scarabeid larvae are extremely important pests of crops in North China. Five species arecommonly found in the fields. Of these Holotrichia diomphalia Bates is the most abundant andinjurious. The other four species, Holotrichia morosa Waterhouse, Anomala corpulenta Motsch.,Anomala sp. and Pentodon patruelis Frivaldsky while not as widespread as the preceding one, arenevertheless injurious in many grain-producing areas. The vertical distribution of the grub populations in the soil was studied. The results indicatedthat the grubs descend deep into the soil to pass the winter in early November, and begin to ascendto the surface and feed on the young plants until October. Some of the grubs descend deep into thesoil when the surface layer of the soil is too dry. The adults of H. diomphalia begin to emerge in early April, flying in maximum numbers dur-ing the middle of May to early June in the Peking area. Holotrichia sp. emerge early in May, andthe flight period extends to late June. Adults of Anomala sp. always appear as early as April butthe maximium population occurs in late May to end of June. The adults of Anomala corpulentaemerge early in May, flying in maximum numbers during June and July. Pentodon patruelis beginto emerge early in May and the flight period extends to July. Field collections indicate that thepreferred food plants of the adults are soybean, hemp, clm, walnut, pear) horsebean, sunflower,wheat, weeds and some shrubs. The seasonal history of H. diomphalia requires about 430 days for its completion in thePeking area, and about 360 days in the southern part of Shantung and Honan provinces. The lifehistories of the other Scarabeids were also discussed. Adults feed on leaves and mate at night. Ovipo-sition starts after mating. Eggs are laid in separate cavities in the soil at a depth of about 5--10 cm.around the infected crop especially in the soybean field. The duration of the egg stage is about10--12 days. The larvae hatch and feed on the roots of the plants. The total larval period ofH. diomphalia is about 340--360 days. Pupae of all the species are commomly present from Mayuntil August and about two to three weeks are required for transformation to the adult stage.更多还原