Abstract: Progress achieved in the past two decades is reviewed in terms of following 5 aspects:①endocrine regulation of reproduction and development,②sensory functions and behavioral specialization,③dispersal and migration,④mechanism of insecticide resistance,and ⑤insect immunity.Reproductive diapause in 3 species of lady beetles due to deficiency in feeding on artificial diets,was partly mended by adding JH analogue ZR512 into the diets,which would promote vilellogenesis and ovary development.In eri silkworm it was found that both PTTH from the brain and ecdysone secreted by prothoracic glands were indispensable for normal development of the ovaries in pupal stage.In Bombyx mori,it was revealed that addition of phytogenous ecdysone into the food would promote RNA synthesis in the silk gland.The induction of trimolters by applying imidazole compounds such as KK-42 to the 3_rd instar larvae of tetramolters,was investigated in the light of the altered action between corpora allata and PTTH secretion in the brain.Delay of MH peak and deficiency of JH were regarded as the cause resulting in trimolter formation.Progress in the studies on sensory function of chemical and visual receptors was achieved in the application of sex pheromones and plant secondary substances for pest control and to unveil the effect of periodic light change on behavioral response.Dispersal capacity of natural enemies of pest insects was studied for biological control,and migration of some mobile insects such as the moths of armyworm and rice leaf roller was studied to reveal the cause of their seasonal occurrence and damages to crops in different regions of the country.The resistance of some medical and agricultural insects to organic phosphorus and pyrethroid insecticides related to gene amplification and changes in sensitivity of the neural target sites to the insecticides,has been investigated and confirmatory results have been obtained.Due attention has been paid to insect immunity in relation to their organic adaptation to harsh environmental elements.

Key words: reproduction, development, endocrine regulation, sensory function, behavioral specialization, dispersal, migration, insecticide resistance, insect immunity