Studies On Antioxidant Defense Response Of Four Types Of Pesticides Stress In Brassica Chinensis

The more vegetable fields were used, the more pests and diseases were occurrenced,pesticides were applied frequently in order to control them, so pesticide residue exceededstandard in vegetables. The pesticide residue on vegetables has been paid more and moreattention by people, but it has relatively few researches that pesticide stresses were affected inphysiology and biochemistry in vegetables. In order to search for biomarkers that it is moresensitive of pesticides stress, and study in depth the response mechanism about plant in differentkinds of pesticides stress. Pyrethroids, organophosphorus, antibioties and botanical insecticideare used to study on antioxidant defense responses of four types of pesticides stress in Brassicachinensi indoor growing. Exogenous salicylic acid has an effect on antioxidant defense of fourtypes of pesticides stress in Brassica chinensi.In study, recommended dose and over lambda-cyhalothrin and chlorpyifos are sprayed inBrassica chinensis, SOD and CAT are inhibited, the activities are lowered significantly. Afterapplying6-8days, SOD activities are close to the control. After applying6-8days, CATactivities are lowered significantly, after applying6-8days, the activities are close to the control.Recommended dose and4times recommended doses emamectin benzoate and matrine aresprayed in Brassica chinensis, SOD and CAT are induced, the activities rose. After applying6-8days, SOD activities are close to the control. After applying2-4days, CAT activities rosesignificantly, after applying6-8days, the activities are close to the control.10timesrecommended doses emamectin benzoate and matrine are sprayed in Brassica chinensis, SODand CAT are inhibited, the activities are lowered. After applying6-8days, SOD activities areclose to the control. After applying2-4days, CAT activities lowered significantly, after applying6-8days, it is close to the control. Recommended dose and over lambda-cyhalothrin, chlorpyifos,emamectin benzoate, and matrine are sprayed in Brassica chinensis, POD is induced, theactivities rose. After applying2days, the activities are greater than the control bylambda-cyhalothrin and chlorpyifos, after applying8days, it is close to the control. Afterapplying2days, the activities are greater than the control by emamectin benzoate and matrine,after applying8days, the activities are still greater than the control.Recommended dose and over lambda-cyhalothrin, chlorpyifos, emamectin benzoate andmatrine were sprayed in Brassica chinensis, after applying2days, the MDA content increased,after applying8days, it was close to the control; after applying2days, the Pro content increased, after applying8days, it was close to the control; after applying2days, the GSH contentincreased, after applying4days, the GSH content was maximum, after applying8days, it wasclose to the control.In short, Brassica chinensis is stressed by pesticide. Its antioxidant system is destroyed,MDA content rose, its result in Brassica chinensis is hurt.Brassica chinensis, is stressed by exogenous salicylic acid, SOD and CAT activities rose,and it was close to the control in short time. The low concentration salicylic acid have no effecton Brassica chinensis stressed by lambda-cyhalothrin, chlorpyifos, emamectin benzoate and matrine.SOD activities rose by exogenous high concentration salicylic acid in Brassica chinensis stressedby10times recommended doses lambda-cyhalothrin and3times recommended doses chlorpyifos.After applying2days, SOD activities had a rising trend. After applying4-6days, it is close to thecontrol. SOD activities lowered by exogenous high concentration salicylic acid in Brassicachinensis stressed by4times recommended doses emamectin benzoate and matrine, after applying4-6days, it was close to the control. After applying2days, CAT activities rose by exogenoushigh concentration salicylic acid in Brassica chinensis stressed by10times recommended doseslambda-cyhalothrin, after applying8days, it was close to the control. After applying8days, CATactivities rose by exogenous high concentration salicylic acid in Brassica chinensis stressed by3times recommended doses chlorpyifos, and it was close to the control. After applying6days, CATactivities lowered by exogenous high concentration salicylic acid in Brassica chinensis stressedby4times recommended doses emamectin benzoate, after applying8days, and it was close to thecontrol. It turned out that SOD and CAT activities rise by exogenous high concentration salicylicacid. In a certain extent it can relieve stress by sprayed four types of pesticides. But the highconcentration salicylic acid has no effect on POD activities, MDA, Pro and GSH content. Theinfluence of salicylic acid in plant stress physiology is complex, it is connected withconcentration. The concentration we used has a little influence on pesticide stress.