The Effect of Exogenous Melatonin in the Regulation of the Degradation of Residual Fungicide in Tomato

Yu Gaobo,Zhou Xingang,Wu Fengzhi,Weijin Peng,Chen Runan,Chen Peng

doi:10.37358/rc.20.6.8214

Abstract

Fungicides are widely used to control pathogen in modern agriculture. In particular, in the process of vegetable production, the use of fungicides could control a variety of diseases to increase crop yield. However, it is common that excessive and unsuitable application of pesticide cause serious pesticide residue in vegetables, which leads to problems of food safety and environment pollution. Therefore, it should not be ignored to reduce fungicide residue in vegetable. In order to confirm the effect of exogenous melatonin on degradation of residual fungicide in plant and explore the mechanism of regulation, Chlorothalonil was taken as experiment material in the present study, and exogenous melatonin was applied as pretreatment to investigate the mechanism of the degradation of residual Chlorothalonil in tomato. It is demonstrated that exogenous melatonin pretreatment could promote the degradation and metabolism of CHT residue in tomato plants by inducing the redox signal, improving the antioxidant system, enhancing antioxidant enzymes and increasing the ratio of GSH/GSSG to scavenge reactive oxygen species. And the activity of GST and GR enzymes were also enhanced to conduct detoxification, which result in a pronounced decrease in the residue of CHT in tomato.

Highlights

Pesticides are widely used to control pathogen, pest and weed in modern agriculture, while the crop production may be lost by 80% without pesticides [1]
In order to confirm the effect of exogenous melatonin on degradation of residual fungicide in plant and explore the mechanism of regulation, Chlorothalonil was taken as experiment material in the present study, and exogenous melatonin was applied as treatment to investigate the mechanism of the degradation of residual Chlorothalonil in tomato
Chemical treatments and sample harvesting Tomato plants with 6 true leaves fully expanded were pretreated with melatonin (3 mM) as treatment (Sigma, USA), while deionized water was utilized as control to explore the effect of melatonin (MT) in the regulation of fungicide degradation. 24 h after pretreatment, tomato leaves were sprayed with chlorothalonil (CHT) at 11.2 mM with 30mL per plant

Summary

Introduction

Pesticides are widely used to control pathogen, pest and weed in modern agriculture, while the crop production may be lost by 80% without pesticides [1]. Problems of food safety and environment pollution could endanger human health directly or indirectly [4] It is mentioned that pesticide residual in vegetable could cause both acute and chronic poisoning, which may cause cancer and other chronic diseases. It has become an urgent problem to reduce pesticide residues in vegetables and explore the mechanism of degradation of residual pesticides in plants. Brassinosteroids has been demonstrated to be a positive regulation factor that promote the degradation of pesticides residue in vegetables in our previous study [1]. A great many studies indicate positive effects of exogenous melatonin on plant resistance to abiotic stresses, until now, little is known about the effect of exogenous melatonin in the regulation of the degradation of residual fungicide in vegetables [10,11,12]. In order to confirm the effect of exogenous melatonin on degradation of residual fungicide in plant and explore the mechanism of regulation, Chlorothalonil was taken as experiment material in the present study, and exogenous melatonin was applied as treatment to investigate the mechanism of the degradation of residual Chlorothalonil in tomato

Plant materials

Results and discussions

Conclusions