胡桃长足象研究初报

胡桃长足象是核桃果实的大害虫,为害损失很大。1975年以来,我们在四川平武地区进行了生活习性观察和防治试验,初步明确了以下几个问题。1.胡桃长足象一年一代。11月份以成虫越冬,次年4月上旬开始活动,为害果、芽、嫩枝、叶柄,5月上旬交尾产卵于果中,一般一果一粒,8月中旬产卵结束,10月陆续死亡。当年成虫6月中旬羽化,进行为害。2.成虫有假死性和向阳性,飞翔力弱,具有与核桃树芽苞相似的保护色。3.防治胡桃长足象,应抓住越冬成虫大量出现和卵孵化盛期时进行。用每毫升含孢量二至五亿的白僵菌液或50%的三硫磷乳油、50%速灭松乳剂、82%磷胺乳剂加水一千倍喷雾,效果良好。

A PRELIMINARY STUDY ON THE LONG-LEGGED WALNUT WEEVIL,Alcidodes sp

The Long-legged walnut weevil,Alcidodes sp.is an important pest and causes serious damage to walnut fruits.Since 1975,biological observations and control tests have been conducted at Pingwu county of Sichuan province.The results obtained during 1975-1977 are herewith summarized:1.The weevil completed life cycle for one generation a year,and over wintered in the adult stage.After hibernation,the weevil became active in April,and began to injure the walnut fruits,buds,young shoots and petioles.Mating and oviposition took place in May,and the oviposition period was quite long,usually lasted until mid August.Eggs were laid in fruitS,and usually only a single egg was laid in each fruit.After the end of oviposition period,the overwintered weevils died away in October.The first appearance of new adults was in mid June.Hibernation took place in November.2.The weevil was a weak flier,and had "death-feigning habit", heliotropism and protective coloration.3.Control measures were tested effectively with a spray of sporesuspension(2-5×10⁸/ml.)of Beauveria bassiana,or 50% trithion,or 50% sumithion,or 82% phosphamiden,the 3 insecticides being applied at a dilution of 1:1000.the proper time for control was suggested atthe peak of the appearance of the overwintered weevil,or of the egghatching period.