BIOLOGICAL AND MORPHOLOGICAL EFFECTS OF CHITINSYNTHESIS INHIBITOR (TRIFLUMURON) ON ANOPHELINE LARVAE

Abstract

Triflumuron (Bay sir 8514) is one of many benzoylated ureas, which inhibit chitin synthesis during insect molting and are commonly referred to as insect growth regulators or I. G. Rs. The post emergence efficacy of triflumuron (SC 48%) was evaluated against larvae of Anopheles stephensi. The first instar larvae were exposed to tirflumuron at LC50 level (0.0001 mg/l) in a continues exposure time. Among 1000 larvae listed 570 were passed to pupal stage (43% morality at the larvae of stage). The dead larvae generally showed different abnormalities, i.e. cuticle of these larvae was dark and thorax of them was inflated. 271 adults, off the pupae, emerged incompletely. At last, only 138 pupae developed completely to adults. It was noted that certain morphological abnormalities became evident in emerged adults. In the emerged adults, generally there were different abnormalities in wing or tarsus. They also showed some difficulties in mating or feeding behaviour in breeding cages. In the end of experiment, 3 out of 13 adults were oviposited. The effect of triflumuron on egg laying of adults was studied and the larvicid did not show any effect on egg laying of adults.