Toxic Effect And Biochemical Mechanisms Of Porphyrin Insecticides On Oxya Chinensis

Oxya chinensis (Thunberg) (Orthoptera: Acridoidea) is a commonspecies of Oxya Serville and widely and abundantly distributes in mostregions of China. This grasshopper species represents an importantagriculture pest to rice and other gramineous crops. Due to the extendedhigh temperature, long-lasting drought and the consequent altemations ingrasshopper breeding environment, the destructive outbreaks of Oxyachinensis had been increasing in China since 1990s. Traditionally, chemicalcontrol has been a major method for protecting rice from damage by Oxyachinensis and is likely to remain an important component of controlstrategies for the foreseeable future. But a great deal of usage chemistryagrochemical to the human body health and the ecosystem environment allresulted in huge of endanger. So we studied a new photosensitiveinsecticide—porphyrin insecticides to control the mortality of Oxyachinensis and we study the biochemical mechanism of it.Oxya chinensis are from Jinyuan district of Taiyuan, Shanxi province,which was sprayed with 5-aminolevulinic acid (ALA) and protoporphyrinⅨ(PpⅨ). The treated Oxya chinensis with ALA occurred to dead at the firstday, and on the second day with the third day try insect death to attain highpeak, and stopped at the fifth day. At the same time, we measured theactivities of the Acetylcholinesterase and the Glutathione S-transferase inOxya chinensis exposed to different concentrations of 5-aminolevulinic acid,distilled water was used as control. The results showed the activities of theAcetylcholinesterase were enhanced and the activities of the GlutathioneS-transferase were decreased compared with control, which suggested5-aminolevulinic acid could activate Acetylcholinesterase and inhibitGlutathione S-transferase, this two enzymes might be involved in themechanism of action mode of 5-aminolevulinic acid. Further studies arenecessary to elucidate relationship between activities ofAcetylcholinesterase, Glutathione S-transferase and 5-aminolevulinic acid in order to explore target of action of 5-aminolevulinic acid.Oxya chinensis that treated with PpⅨstars a great deal of death at thefirst day after use insecticides, and hereafter reduce gradually, the deathstopped and the fifth day. PpⅨpoisons to mortality effect to the Oxyachinensis with the amount of that it use to present relativity. At the sametime, we studied the influence of the PpⅨto the antioxidative enzymes, wemeasured the activities of Hydrogen Peroxidase(CAT), GlutathioneReductase(GR), Glutathione S-transferase(GST), Glutathioneperoxidase(GSH-PX) and Superoxide Dismutase(SOD) exposed to differentconcentrations of PpⅨ, distilled water was used as control. The result showsthat PpⅨCould activate Hydrogen Peroxidase, Glutathione S-transferaseand Glutathione peroxidase of the Oxya chinensis, and PpⅨmay inhibitGlutathione Reductase of the Oxya chinensis.Through the study of the effect and biochemical influence of theporphyrin insecticides to the Oxya chinensis, we can see that usingporphyrin insecticides to manage Oxya chinensis is a potential, viablemethod. But if the real application wanted to chase it in actual, we need todo more investigation to seek suitable dosage, treated time and biochemicalmechanism.