Biological and ecological studies of the parasitoidChelonus inanitus [Hym.: Braconidae] in Israel

The effects of certain environmental conditions on the survival ofChelonus inanitus (L.) adults were studied in the laboratory. The longevity of the adults decreased with increase in temperature. The survival of males and females under extreme conditions of temperature and humidity was negatively correlated with the duration of exposure. For short periods of exposure the survival ofC. inanitus adults was influenced by high temperatures, the lethal exposure time decreased when the parasitoids had been exposed to high temperatures. Change in the saturation deficit did not affect the survival rate. Different kinds of food available in the field such as flowers of cotton and alfalfa, cotton nectars and excretion of common aphids, did not prolong the life span ofC. inanitus adults in comparison with parasitoids that had not received food or water. The 50% mortality of males that had been fed on cane-sugar with water, honey, flowers of alfalfa or flowers of cotton, was 15, 23, 5 and 5 days respectively, while these values for females that had been fed on the same type of food were 23, 35, 5 and 3 days respectively.