二甲戊灵对高粱种植土壤酶活性和微生物的影响

Impacts of pendimethalin on soil enzyme activity and microbial community in sorghum cultivation

[目的]本文旨在研究山西地区土壤施用二甲戊灵对土壤酶活性与微生物的影响,探究其影响的潜在机制,为科学使用二甲戊灵提供科学依据。[方法]以室内盆栽和大田栽培2种方式种植高粱后的土壤为研究对象,探究不同浓度二甲戊灵处理对4种土壤酶(蔗糖酶、脲酶、过氧化氢酶、多酚氧化酶)活性与土壤微生物的影响,并通过传统平板计数法和PCR‐DGGE相结合方式对细菌和真菌群落进行统计分析。[结果]盆栽和大田栽培2种方式下,施用二甲戊灵浓度在200~800 g·hm^(-2)范围内对蔗糖酶、脲酶、多酚氧化酶均呈激活作用,过氧化氢酶活性表现为不同程度的降低或无显著变化。在400 g·hm^(-2)时,蔗糖酶活性达到顶峰;浓度达到600 g·hm^(-2)时,过氧化氢酶的活性被显著抑制;而浓度达到800 g·hm^(-2)时,脲酶活性达到最大。二甲戊灵对土壤细菌和真菌呈现激活作用,该影响随二甲戊灵施用浓度变化而变化。细菌和真菌群落对二甲戊灵浓度变化较为敏感;施用二甲戊灵会导致土壤生物活性变化。[结论]不同浓度的二甲戊灵对土壤中的蔗糖酶、脲酶、多酚氧化酶活性均被一定程度的激活,同时影响微生物数量和群落多样性,尤其Myxococcus属细菌和Stigmalychus属真菌影响最为显著。

[Objective]The purpose of this study was to investigate the effect of pendimethalin on soil enzyme activity and micro⁃organism diversity in Shanxi region,and to explore the potential mechanism of its effects to provide scientific basis for the ratio⁃nal use of pendimethalin.[Methods]The study was conducted with indoor pots and field cultivation methods to investigate the effects of different concentrations of pendimethalin on the activity of four soil enzymes(sucrase,urease,catalase,and polyphe⁃nol oxidase)and the diversity of soil microorganisms after planting.The bacterial and fungal communities were statistically ana⁃lyzed using traditional plate counting and PCR-DGGE combined method.[Results]The results showed that under both indoor pot and field cultivation methods,the application of pendimethalin at concentrations of 200~800 g·hm^(-2) had a stimulating effect on sucrase,urease,and polyphenol oxidase,while the activity of peroxidase showed a varying degree of reduction or no signifi⁃cant change.The activity of sucrose and urease peaked at 400 g·hm^(-2)and 800 g·hm^(-2),respectively,while the peroxidase activi⁃ty was significantly inhibited at 600 g·hm^(-2).Pendimethalin showed an activating effect on soil bacteria and fungi,and this effect varied with the concentration of pendimethalin applied.The bacterial and fungal communities were more sensitive to changes in pendimethalin concentration,and the application of pendimethalin led to changes in soil biological activity.[Conclusion]Differ⁃ent concentrations of pendimethalin had a certain degree of activation on soil sucrase,urease,and polyphenol oxidase activity,while affecting the quantity and community diversity of microorganisms,especially the significant impact on Myxococcus bacte⁃ria and Stigmalys fungi.