【摘要】 <正> 七星瓢虫(Coccinella septempunctata)是蚜虫的重要天敌。1970年以来,在我国北方棉区大面积利用七星瓢虫防治棉蚜已取得优良成绩。为了确保瓢虫的来源以满足冶蚜在时间和数量上的要求,需要研究代饲料来维持越冬瓢虫的种群或进行人工繁殖。我们在1975年冬开始瓢虫代饲料的研究,证明以鲜猪肝、蜂蜜等配制的饲料能使成虫存活并产卵(动物所昆虫生理室,1977;动物所昆虫生理室等,1977)。我们注意到不同食料对成虫体重和产卵量均有明显影响;并认为取食量是一个主要问题,要提高以代饲料饲养瓢虫的工作,须先设法增加瓢虫对代饲料的取食量。更多还原

【Abstract】 Food specificity and nutrition of entomophagous insects form an important area in entomological research. Their voracity and food utilization, together with the specialities in dietary requirements and reproductive activities would give the indispensable knowledge in the task of augmentation of natural enemies to control insect pests. The present work deals with the influence of different diets on the feeding and fecundity of Coccinella scptempunctata L. on a quantitive basis.Our results show that the adults of this species display a marked difference in food ingestion when feeding on aphide or on artificial diet composed of fresh porcine liver homogenate and honey (in 5:1w/w). When feeding on aphids each female would consume 20 mg of food daily and a peak of ingestion appeared about 3-5 days after adult emergence, which amounted to 30% of the total food ingested in a rearing period of 22 days. When feeding on the artificial diet, food intake was low in the early stage and would increase in the latter dates. This phenomenon perhaps shows the adaptive course which is usually followed when an insect is feeding on a suboptimal diet. The artificial diet consumed by a female beetle in 24 hours weighed only about one-fifth of the aphids consumed during the same duration.Food intake was closely related to the changes in body weight and fecundity and the quality of diets had conspicuous influence on the ovarian development and thus the fecundity of the beetle. When feeding on the artificial diet, the preovipo-sitional period of the female beetle was prolonged and the percentage of ovipositing individuals and the number of eggs laid were low, due to the smaller food intake and the slow accumulation of reserve materials in the fat body. Our results also show a difference in the efficiency of food utilization and food conversion when different diets are used in the rearing work.更多还原