EFFECTS OF CHLORFLUAZURON ON THE REPRODUCTION OF SPODOPTERA LITURA

Lethal doses of chlorfluazuron, when applied topically to 5th instars or pupae of S. litura, caused toxicity & malformations, which ultimately lead to the death of organism. Sublethal doses of it, when applied to fifth-instars or pupae, caused significant reduction in reproduction and effects on viability. Sublethal-doses were topically applied to 5th instars, significantly reduced ovarian and testicular development. The same doses also significantly reduced number of inseminated sperm. Interference bychlorfluazuron, transferred by copulation through sperm fluids or ova, appears improbable. The significant variations in the egg contents were observed during embryogenesis. Morphological characteristics were divided into eight embryonic developmental stages during 0-84 h of development onthe basis of microscopic examinations. Sublethal-doses of chlorfluazuron reduced the fecundity, fertility and hatchability which were caused by direct effects on reproductive organs. This is an important discovery, as it provides an important clue to the mechanism of chlorfluazuron action, which has great impact on insect physiology and toxicology.