外源水杨酸对喜树幼苗盐害胁迫缓解效应的生理机制初探  

Physiological Mechanism of Mitigative Effects of Salicylic Acid on Salt-Stressed Camptotheca acuminata Seedlings

作　　者：孟长军[1] 杜喜春[1] 赵银萍[1] MENG Changjun;DU Xichun;ZHAO Yinping(College of Biology and Environmental Engineering,Xi'an Art and Science University/Research Center of Wild Ornamental Plants in Qinling Mountains,Xi'an 710065,China)

机构地区：[1]西安文理学院生物与环境工程学院/秦岭野生观赏植物研究中心,西安710065

出　　处：《东北农业科学》2018年第3期23-27,共5页Journal of Northeast Agricultural Sciences

基　　金：西安市科技计划项目文理专项(CXY1352WL16);省级大学生创新创业训练计划(09009001065)

摘　　要：为了明确外源水杨酸对喜树幼苗盐害胁迫缓解效应的生理机制,以喜树幼苗为试验材料,以0.5%NaCl胁迫为对照,设4个处理:T1(0.5%NaCl+60 mg/L SA喷叶),T2(0.5%NaCl+60 mg/L SA灌根),T3(0.5%NaCl+120 mg/L SA喷叶),T4(0.5%NaCl+120 mg/L SA灌根)。通过比较不同处理间喜树幼苗的超氧化物歧化酶活性、过氧化物酶活性、可溶性蛋白含量、丙二醛含量以及干重发现:60 mg/L的水杨酸处理对喜树幼苗NaCl胁迫的缓解作用效果最佳,且喷叶处理的效果优于灌根处理。60 mg/L水杨酸喷叶处理盐胁迫下喜树幼苗叶片中的保护酶活性和渗透调节物质含量均显著增加,叶片中的丙二醛含量显著下降,喜树幼苗的干重则显著高于对照。表明外施适宜浓度的水杨酸可增强盐胁迫下喜树幼苗的抗氧化物酶活性并增加渗透调节物质含量,进而保护了植物光合膜的完整性,提高了细胞的保水能力,并最终促进了盐胁迫下喜树幼苗的生长。通过研究水杨酸缓解喜树幼苗盐害的生理机制,为喜树的抗盐栽培提供了一些理论依据和参考。To determine the physiological mechanism of mitigative effects of salicylic acid on salt-stressed Camptotheca acuminata seedlings,under the control of 0.5% NaCl stress,4 treatments were set up:T1(0.5% NaCl+60 mg/L SA foliar spray),T2(0.5% NaCl+60 mg/L SA root irrigation),T3(0.5% NaCl+120 mg/L SA foliar spray)and T4(0.5% NaCl+120 mg/L SA root irrigation).Through the comparison of Camptotheca acuminata seedlings′antioxidant enzyme activity,soluble protein content,MDA content as well as dry weight,we found that the mitigative effects of 60 mg/L SA was best,and the result of foliar spraying was better than that of root irrigating.Under the treatment of 60 mg/L SA foliar spraying,activity of protective enzymes in leaves of Camptotheca acuminata seedlingsand content of osmotic adjustment substances increased significantly,MDA content decreased significantly,the dryweights of seedlings were higher than those of control significantly.This showed that application of salicylic acid atsuitable concentration could enhance antioxidant enzyme activity,increase the content of osmotic adjustment substances,thus protecting the integrity of the photosynthetic membrane,increasing cell water retention capacity,andultimately promoting the growth of seedlings under salt stress.By studying the physiological mechanism of mitigative effects of salicylic acid on salt-stressed Camptotheca acuminata seedlings,theoretical basis was provided forsalt tolerance cultivation of Camptotheca acuminata.

关 键 词：水杨酸 喜树 抗氧化物酶 可溶性蛋白 干重 

分 类 号：S567.19[农业科学—中草药栽培]