2种农药胁迫对油桐幼苗叶绿素荧光特性及生长的影响  

Effects of Pesticides Stress on the Chlorophyll Fluorescence Characteristics and Growth of Vernicia fordii Seedlings

作　　者：万盼[1] 熊兴政[1] 黄小辉[1] 邬静淳 欧阳[1] 邓雪梅[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

出　　处：《林业科学》2016年第7期22-29,共8页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目"木本植物对三峡库区消落带异质生境的响应及其适应性"(31370602)

摘　　要：【目的】探讨农药胁迫对油桐幼苗叶绿素荧光特性及生长的影响,为科学指导三峡库区油桐种植、减少库区面源污染提供理论参考。【方法】以盆栽油桐幼苗为材料,在其土壤中喷施不同浓度百草枯(原药/水=1/50,1/100,1/200,1/400和1/800)和氰戊·乐果(原药/水=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)为对照,并分别在处理后第30天测定幼苗叶绿素含量和荧光特性,第60天测定其生长指标。【结果】百草枯和氰戊·乐果处理均可降低油桐幼苗叶绿素含量,其浓度越高叶绿素含量越低,且高浓度(百草枯≥1/200,氰戊·乐果≥1/500)处理下差异均达到显著水平(P<0.05)。高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理下,油桐幼苗的PSⅡ最大光化学效率(Fv/Fm)、光化学猝灭系数(qP)和电子传递速率(ETR)均显著低于对照(P<0.05),而非光化学淬灭系数(NPQ)则显著高于对照(P<0.05);商品规定施用浓度(百草枯=1/400,氰戊·乐果=1/1 000)处理下,油桐幼苗的Fv/Fm,qP,ETR和NPQ均低于对照(CK),但差异未达显著水平(P>0.05)(氰戊·乐果处理下油桐幼苗的ETR显著低于对照除外)。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(P<0.05),且浓度越高抑制作用越强;商品规定施用浓度处理下,百草枯(1/400)可促进油桐幼苗株高、地径和单株生物量的生长,氰戊·乐果(1/1 000)则抑制油桐幼苗株高和单株生物量的生长,却可促进幼苗地径的生长,但这些差异均未达显著水平(P>0.05)。高浓度百草枯(≥1/200)和氰戊·乐果(≥1/500)处理均显著抑制油桐幼苗的根冠比生长(P<0.05);商品规定施用浓度百草枯(1/400)和氰戊·乐果(1/1 000)分别促进和抑制油桐幼苗根冠比的生长,但差异均未达到显著水平(P>0.05)。【结论】高浓度百草枯和氰戊·乐果能够显著降低油桐幼苗叶�【Objective】In this study,the chlorophyll fluorescence characteristics and growth of Vernicia fordii（ tung-oil） seedlings under pesticides stress were analyzed in order to guide tung oil cultivation and provide theoretical references for reducing non- point source pollution in the Three Gorges Reservoir Area. 【Method】A pot experiment was conducted to study and compare the chlorophyll contents,chlorophyll fluorescence and growth of tung-oil seedlings under different concentrations of paraquat and fenvalerate-dimerthoate. Levels of paraquat and fenvalerate-dimerthoate were technical /water = 1 /50,1 /100,1 /200,1 /400 and 1 /800 and technical / water = 1 /125,1 /250,1 /500,1 /1 000 and 1 /2 000,respectively. Water treatment served as control. 【Results】Results showed that the chlorophyll content differed under different concentrations of paraquat and fenvalerate-dimerthoate and the chlorophyll content decreased with increasing concentration. These differences were significant in the high concentrations treatment（ paraquat≥1 /200 and fenvaleratedimerthoate≥1 /500）. The（ Fv/ Fm） of PSⅡ,qPand ETR of tung-oil seedlings under high concentrations of paraquat（ ≥1 /200） and fenvalerate-dimerthoate（ ≥1 /500） were significantly lower than the CK（ P〈0. 05）,but the NPQ wasobviously higher than the CK（ P〈0. 05）. The（ Fv/ Fm）,（ qP）,（ ETR） and（ NPQ） of tung-oil seedlings under the commodity provision concentration of paraquat（ 1 /400） and fenvalerate-dimerthoate（ 1 /1 000） were lower than CK with an exception of ETR under the treatment of fenvalerate-dimerthoate,but the differences were not statistically significant.High concentration of paraquat（ ≥1 /200） and fenvalerate-dimerthoate（ ≥1 /500） inhibited the growth of plant height,diameter and biomass per plant of tung-oil seedlings（ P〈0. 05）,and the higher the concentration was used the stronger inhibition effect can be detected. Paraquat in the commodity provision concentration（ 1 /40

关 键 词：油桐 农药胁迫 叶绿素荧光特性 生长量 

分 类 号：Q948.1[生物学—植物学] S714.2[农业科学—林学]