| Phthalate esters,which called PAEs,are a typical endocrine disruptor.Due to the widely used of PAEs and the combination with plastic products,it was extremely easy to release them into the water,atmosphere and soil,causing pollution to the environment.At present,there have been a lot of researches on PAEs,but most of them focus on animals,microorganisms,and relatively few studies on crops.Therefore,it has received widespread attention from world to understand the toxic effects of PAEs on crops and their effects on human health.As a typical phthalate,it can not ignore the toxic effect of DEHP on the ecological environment.In this study,we used typical phthalate DEHP as a pollutant and wheat seedlings as model organisms.The soil was exposed to four concentrations(CK,1 mg·kg-1,10 mg·kg-1,100 mg·kg-1),and wheat was cultured for 30 days with the soil.The growth parameters?the height plant,the length of root?,germination rate,chlorophyll content,internal antioxidant enzyme system of wheat seedlings,soluble sugar,and malondialdehyde content in wheat were cultivated for 10th,20th,and 30th days,respectively.And the expressions of genes were measured and comprehensively analyzed.The research studied the ecotoxic effects of DEHP on wheat,and the mechanism of action of DEHP on wheat was researched in depth to provide a basis for improving the safe production of agricultural products.The main results of this study are as follows:?1?In terms of growth indicators,DEHP had certain inhibitory effects on the germination rate of wheat.In the early stage of the test,the inhibitory effect of DEHP on the germination rate of wheat was 5.3%,9.2%,and 13.7%at concentrations of 1 mg·kg-1,10 mg·kg-1,and 100mg·kg-1,respectively.And there was no obvious inhibitory effect on the plant height of wheat.In the later stage of the experiment,it showed an inhibitory effect on the root length of wheat.When the concentration was 100 mg·kg-1,the inhibitory rate reached 20.44%.?2?In terms of physiological indicators,the contents of chlorophyll and soluble sugar in wheat seedlings changed significantly after being exposed to DEHP.DEHP showed a promotion effect first and then showed an inhibition effect on the three chlorophyll contents.The content of soluble sugar showed a tendency to inhibit first and then promote the last inhibition.?3?After DEHP poisoning,oxidative damage has been occurred in wheat.The content of MDA has been inhibited.The antioxidant enzyme activity of wheat has been promoted or inhibited to varying degrees,and the content of GSH has also been inhibited to varying degrees,indicating that the presence of DEHP had negative effects on wheat.?4?The calculation of six indicators of wheat and the comprehensive analysis of IBR showed that the order of toxic effects of different concentrations of DEHP was:100 mg·kg-1>10 mg·kg-1>1 mg·kg-1,which was consistent with the analysis of the ecotoxic effects on enzyme activity.?5?The analysis of the relative expression levels of the antioxidant enzyme genes and heat shock protein genes in wheat showed that DEHP promoted the expression of anti-oxidase genes,and had a certain inhibitory effect on the expression of heat shock protein genes.In summary,in this study,DEHP was used as pollutant to comprehensively measure and analyze the growth indicators,physiological indicators,oxidative damage,gene expression and other indicators of wheat seedlings.The research results showed that the presence of DEHP had toxic effects on wheat. |
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