The Impact Of The Coriaria Toxins On Insect Physiology And Anatomical Structure

Coriaria lactone is one of sequiterpenoid lactones from the plants of Coriaria genus and loranthus parcisiticus , which belong to picrotoxinin sequiterpenoid . There are four kinds of coriaria lactone, including Coriamyrtin,Tutin , Coriatin and corianin , which virulence had been recognized for long time . At the beginning, the domestic and external scholars studied it on the cattle, rat, lapin, fish , pig and cat etc , the result showed that the physiological effect of Coriaria lactone was similar to that of picrotoxinin , which effected nerve system , made the muscle and respiration exited and the vascular contracted , animated the heart restraint center so lead to the animal coma , startle , spasm etc symptom .Lately , Coriaria lactone was used to be the medicine of treating psychosis and the tool of nerve science study . Professor Menglou Li of Northwest forestry college applied it to control pest and found that Coriaria lactone can inhibit insect feeding and toxic it. Based on the above study, through biochemical analysis method and tissue pathological study, the physiological effect of Coriaria lactone oninsect was studied .The study result is as following:1.The effect of Coriaria lactone on amino acid nerve transmission substance: Coriaria lactone is a kind of nerve toxicant can made amino acid nerve transmission substance content of insect change and the content of GABA increase obviously, the content of Glu change little or decrease slightly. If Coriaria lactone was intruded to the pest body it can lead to the symptom of exiting-spitting out liquid-paralysis-coma-death, which indicted that Coriaria lactone is one special inhibiting matter of insect nerve transmission. 2.The effect of Coriaria lactone on physical and chemical quality of insect hemolymph : Coriaria lactone can effect the insect hemolymph and made the hemolymph content increase , the conductivity and acidity change in the same time.3.The effect of Coriaria lactone on the excretory system of insect: The insect excretory ability was effected by Coriaria lactone and the ability of excreting dye was decreased and at the same time the Malpighian tubules and kidney diameter was enlarged.4.The effect of Coriaria lactone on the midgut tissue: The insect digestion system was effected and the midgut peritrophic membrane was destroyed even disorganized and separated from the muscle layer and came from the midgut finally. At the same time, the microvilli of the column cell are confused and sloughed off. In conclusion, the effect of Coriaria lactone on insect is complex. Besides inhibiting feeding and poisoning stomach it can effect on nerve system of insect,which lead to GABA content increasing and the test insect had the symptom of exiting-spitting out liquid-paralysis-coma-death; at the same time, the digestive and excretory system were effected, the internal gut membrane was destroyed, the Malpighian tubules and kidney were enlarged.