农药施用浓度对油桐幼苗生长及土壤酶活性、有效养分含量的影响  

Effects of pesticides on soil enzyme activities,available nutrients and growth of Vernicia fordii seedlings

作　　者：万盼[1,2] 黄小辉[1] 熊兴政[1] 刘芸[1] 

机构地区：[1]西南大学资源环境学院林学系,重庆400716 [2]中国林业科学研究院林业研究所,国家林业局林木培育重点实验室,北京100091

出　　处：《南京林业大学学报（自然科学版）》2018年第1期73-80,共8页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家自然科学基金项目(31370602)

摘　　要：【目的】通过研究施用不同浓度百草枯和氰戊·乐果对油桐幼苗土壤酶活性和养分含量的影响,为在三峡库区实施油桐科学种植、减少库区面源污染提供参考。【方法】以盆栽油桐幼苗为材料,对其土壤喷施不同浓度百草枯(原药与水体积比为1/50、1/100、1/200、1/400和1/800)和氰戊·乐果(原药与水体积比为1/125、1/250、1/500、1/1 000和1/2 000),以喷施清水(放置6 h的自来水)作为对照,分别在处理后的第30天和第60天测定油桐幼苗土壤酶活性、有效养分含量和幼苗生长状况。【结果】百草枯和氰戊·乐果处理下,土壤pH与对照无显著差异(P>0.05)。高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理下,土壤脲酶、蛋白酶、过氧化氢酶和碱性磷酸酶活性在处理后30和60 d均低于对照,且在处理30 d后差异达显著水平(P<0.05);商品规定施用浓度百草枯(1/400)和氰戊·乐果(1/1 000)处理30和60 d后,土壤脲酶和碱性磷酸酶活性高于对照(除氰戊·乐果处理的土壤碱性磷酸酶活性低于对照),而土壤蛋白酶和过氧化氢酶却低于对照,但它们的差异均未达显著水平(P>0.05)。在高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理30和60 d后均显著降低了土壤碱解氮含量(P<0.05);在商品规定施用浓度百草枯(1/400)和氰戊·乐果(1/1 000)处理30和60 d后,土壤碱解氮含量略微上升,但差异不显著(P>0.05)。同样,高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理下土壤有效磷和速效钾含量在30和60 d均显著高于对照(P>0.05);而商品规定施用浓度处理下(百草枯(1/400),氰戊·乐果(1/1 000))的土壤有效磷和速效钾含量则低于对照,但差异不显著(P>0.05)。相关性分析表明,有效磷和速效钾均与脲酶、蛋白酶和过氧化氢酶呈极显著负相关。高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理对油桐幼苗株高、地径和单株生物量的生长均有显著抑制作用(【Objective】The study aimed to provide a scientific guidance for the timing of planting oil tree and a theoretical reference to reducing non-point source pollution in the Three Gorges Reservoir Region.【Method 】Vernicia fordii（Hemsl.） Airy Shaw seedlings were grown in pot soil under different concentrations of paraquat（volume ratio of the original medicine and water of 1/50,1/100,1/200,1/400,and 1/800） and dimerthoate（volume ratio of the original medicine and water of 1/125,1/250,1/500,1/1 000,and 1/2 000）,with water as a control（CK）,and the soil enzyme activities,efficiency nutrient content,and growth of seedlings were measured after 30 and 60 days,respectively.【Result】The p H was not significantly difference among pesticides treatments and CK（P 0.05）.The soil urease,protease,catalase,and alkaline phosphatase of soil had lower activity than that of CK,30 or 60 days after treatment with high concentrations（paraquat ≥1/200,fenvalerate-dimerthoate≥1/500）,and the differences between them were significant in 30 days（P 0.05）.However,the urease and alkaline phosphatase of soil had slightly higher activity than that of CK（alkaline phosphatasewas excluded）,the protease and catalase of soil had slightly lower activity than CK had,all of them were studied 30 and 60 days after treatment with conventional concentrations（paraquat = 1/400,fenvaleratedimerthoate = 1/1 000）,but the differences between them were not significant in 30 or 60 days（P 0.05）.The nitrogen content was significantly decreased 30 or 60 days after treatment with high concentrations（paraquat ≥ 1/200,fenvalerate-dimerthoate ≥ 1/500）,but the nitrogen content was not significantly different between the CK and the pesticide treatment with conventional concentration（paraquat,1/400; fenvalerate-dimerthoate,1/1 000）（P 0.05）.Similarly,the available P and available K contents were higher than that in CK,30 and 60 days after treatment with concentrations（paraquat ≥ 1/200,fenvalerate-dimerthoate

关 键 词：百草枯 氰戊·乐果 土壤酶活性 有效养分含量 油桐苗 三峡库区 

分 类 号：S714.2[农业科学—林学]