外源脯氨酸对番茄体内残留百菌清降解的调控作用

Effect of exogenous proline on degradation of residual chlorothalonil in tomato

为探索外源脯氨酸(Pro)对番茄残留农药降解代谢的调控作用,以番茄浙杂205为供试植物,以杀菌剂百菌清为供试农药,研究外源Pro对番茄体内喷施百菌清后的农药残留量、活性氧含量、抗氧化酶和解毒酶的影响。研究表明,外源3 mmol·L^-1的Pro预处理显著降低了百菌清处理7 d后番茄体内的农药残留量。与对照相比,外源Pro预处理可显著提高百菌清处理后番茄过氧化物酶(POD)、超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、单脱氢抗坏血酸还原酶(MDAR)的活性,进一步提高农药处理后12~96 h的GSH/GSSG比值,及谷胱甘肽还原酶(GR)、谷胱甘肽S-转移酶(GST)活性和非蛋白结合态巯基化合物(NPT)含量。因此,外源喷施Pro可提高SOD、MDAR、CAT、POD等抗氧化酶活性,促进GSH的再生,提高GST等解毒酶活性,从而加速番茄体内百菌清的降解代谢,为促进蔬菜残留农药的降解提供一条新途径。

In order to explore the regulation of exogenous proline(Pro)on degradation of residual pesticide in tomato,Zheza 205 was taken as the tested plant and the fungicide chlorothalonil was applied to study the effect of exogenous Pro on pesticide residues.The content of reactive oxygen species(ROS),and the activity of antioxidant enzymes and detoxification enzymes after the application of chlorothalonil were investigated.The results showed that pretreatment of Pro(3 mmol·L-1)reduced the pesticide residue in tomato significantly after 7 days of chlorothalonil application.Compared with the control,exogenous Pro pretreatment could induce the activity of tomato peroxidase(POD),superoxide dismutase(SOD),ascorbate peroxidase(APX),monodehydroascorbic acid reductase(MDAR)significantly after the treatment of chlorothalonil,and increase the GSH/GSSG ratio during the 12-96 h period after pesticide treatment,as well as the activity of glutathione reductase(GR),glutathione S-transferase(GST),and the content of non protein bound thiols(NPT).Therefore,pretreatment of Pro could induce the activity of antioxidant enzymes and GST detoxification enzyme and improve the regeneration of GSH,and thus promote the degradation and metabolism of chlorothalonil in tomato.This study provided a new way to promote the degradation of pesticide residue in vegetables.