核桃凋落叶分解对莴笋抗氧化系统及光合特性的影响  

Effects of Decomposing Walnut Leaf Litter on Antioxidant Systems,Photosynthetic Characteristics and Growth of Lettuce

作　　者：丁伟[1] 胡庭兴[1] 李仲彬[1] 陈洪[1] 贺维[1] 史洪洲 王茜[1] 胡红玲[1] 

机构地区：[1]四川农业大学林学院四川省林业生态工程重点实验室,四川雅安625014

出　　处：《西北植物学报》2014年第4期769-777,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家“十二五”科技支撑计划(2011BAC09B05);四川省“十二五”农作物育种攻关课题(2011NZ0098-10)

摘　　要：为探讨核桃对农作物的化感作用,该试验采用盆栽法,设置4个凋落叶施用量水平(0、30、60、90g/盆),研究了核桃凋落叶在土壤中自然分解过程中对莴笋(播种后80、100、120和140d)抗氧化系统、光合生理特征及其生长的影响。结果显示:(1)核桃凋落叶处理的莴笋叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性在播种80d时得到促进,在100d时受到抑制,而在120d之后基本恢复至正常水平,并以SOD表现最为敏感。(2)核桃凋落叶处理100和120d时,莴笋叶片可溶性蛋白(SP)含量显著降低,而可溶性糖(SS)含量显著增加。(3)核桃凋落叶处理100、120d时,莴笋叶片净光合速率(Pn)受到显著抑制,各处理气孔导度(Gs)和蒸腾速率(Tr)显著低于对照。(4)核桃凋落叶处理的莴笋株高、地上部分生物量及地上部分占总生物量比重在处理120d时均显著低于对照,在140d时基本恢复正常。研究表明,核桃凋落叶在土壤中分解对莴笋产生的化感作用强度随分解时间延长呈现出逐渐增强后再减弱的变化趋势;莴笋可以通过调控自身的保护酶活性和渗透调节物质含量在一定程度上缓解化感物质伤害,对核桃凋落叶的化感作用有较强的耐受能力,生产中可以在核桃林下进行间作或者套作莴笋。In order to investigate the allelopathic effect of walnut （Juglans regia） on crops,we conducted a pot experiment to study the impacts of naturally decomposing walnut leaf litter in soil on the resistance physiology,photosynthetic parameters and growth traits of lettuce （Lactuca sativa）. The present experi- ment included a control （CK,without leaf litter addition in soil） and three treatments （with 30,60,90 g pot- leaf litter fragments, respectively, correspondingly denoted as T1, T2, T3 ）. In each treatment the cor- responding amount of leaf litter fragments were mixed with pre-weighed soil （8 kg pot-） ,and lettuce seeds were sowed. The indexes related to morphology,resistance and photosynthesis of lettuce were meas-ured at 80,100,120,and 140 d after sowing. The results showed that： （1）The activities of superoxide dis- mutase （SOD） ,peroxidase （POD） and catalase （CAT） in leaves of lettuce treated with leaf litter were pro- moted at 80 d,but were restrained at 100 d,then recovered to the control level at 120 d. SOD was the most sensitive enzyme to the allelopathic effect of walnut leaf litter. At 100 d of sowing, the malondialdehyde （MDA） content in leaves of lettuce was significantly enhanced by each leaf litter treatment compared to CK; （2）Treated with the leaf litter,the content of soluble protein （SP） decreased,while soluble sugar （SS） increased obviously at 100 d and 120 d; （3）At 100 d and 120 d,the net photosynthetic rate （Pn） was inhibi- ted by each leaf litter treatment,accompanied with the decrease of stomatal conductance （Gs） and transpi- ration rate （Tr）; （4）Height, aboveground biomass and its proportion in total biomass were significantly lower than that in CK after 120 d of treatment,while the suppression compromised at 140 d （without sig- nificant differenees between any leaf litter treatment and CK）. In the present research, the allelopathic effect of decomposing walnut leaf litter exhibited an up-down trend with the pro

关 键 词：核桃 凋落叶 农林复合 化感作用 抗性生理 

分 类 号：Q945.79[生物学—植物学]