超敏蛋白对低温胁迫下核桃生理特性的影响  

Effect of harpin on physiological characteristics of walnut under low temperature stress

作　　者：刘杜玲[1] 彭少兵[1] 张博勇[1] 刘朝斌[1] LIU Duling PENG Shaobing ZHANG Boyong LIU Chaobin(Key Laboratory of Silviculture on the Loess Plateau State Forestry Administration, Northwest A ＆ F University, Yangling 712100, Shaanxi, China)

机构地区：[1]西北农林科技大学黄土高原林木培育重点开放实验室,陕西杨凌712100

出　　处：《果树学报》2017年第6期698-705,共8页Journal of Fruit Science

基　　金：陕西省农业攻关项目(2014K01-10-01)

摘　　要：【目的】研究超敏蛋白对低温胁迫下核桃生理特性的影响,探讨其提高核桃抗寒性可能的作用机制,为超敏蛋白在核桃抗逆生产中的应用提供理论依据。【方法】以抗寒力较弱的早实核桃品种‘香玲’为试材,采用大田喷施与室内模拟低温环境处理相结合的方法,测定低温(2、0、-2、-4、-6℃)胁迫下核桃叶片的相对电导率、丙二醛(MDA)含量、可溶性蛋白含量、可溶性糖含量、脯氨酸含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性,探究超敏蛋白在核桃响应低温胁迫中的作用。【结果】随着温度的降低,核桃叶片相对电导率、丙二醛含量、可溶性蛋白含量、脯氨酸含量及超氧化物岐化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性均升高,可溶性糖含量降低;喷施超敏蛋白可显著降低0℃以下低温胁迫核桃叶片的相对电导率、丙二醛含量,显著提高可溶性蛋白含量、脯氨酸含量和超氧化物岐化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性,对可溶性糖含量影响不大。【结论】喷施超敏蛋白可以提高低温胁迫下核桃叶片脯氨酸含量和可溶性蛋白含量,增强抗氧化酶活性,降低相对电导率和MDA含量,以维持细胞正常的生理代谢,防止膜脂过氧化和保护细胞膜结构的稳定性,增强核桃的抗寒性。[Objective] ＇Xiangling＇ is an early fruiting walnut cultivar widely cultivated in north China, but it is susceptible to cold and often damaged by late frost, which results in significant decline in yield or even total crop failure. Harpin is a stable polypeptide isolated from Erwinia amylovory, and has been used as a pure biopesticide that induce resistance in plants. In this study, the effect of harpin on physiological characteristics of walnut under low temperature stress was studied in order to explore the mechanism of harpin improving cold resistance of walnut and to provide theoretical basis for the application of harpin in walnut production. [ Methods ] 1.5 g· L^-1 of harpin was sprayed to 6-year-old trees of walnut cultivar ＇ Xiangling＇ prior to female flower stage with distilled water spray as the control. The experiment was conducted with a random block design, with 5 trees in each of 3 blocks. 7 d after spraying, shoots of the same diameter and length were sampled from the same direction of the canopy of each treated walnut tree and placed into a phytotron （RXZ-0288）and exposed to different low temperatures （2, 0, -2, -4 and -6 ℃）. The temperature in the phytotron was initially set at 10 ℃ and programmed to decrease at a rate of 4 ℃ · h^-1 and maintained at each target low temperature for 8 h, and then the temperature was set to 10 ℃ again. The third leaf from the top was taken from the young sprout after 5 h at 10 ℃. The samples were frozen in liquid nitrogen and stored under -70 ℃. The relative electricity conductivity was determined using an electricity conductivity meter. Soluble protein was determined with coomassie brilliant blue. Soluble sugars were determined with anthrone colorimetric method, proline content with acidic-ninhydrin reaction method, and malondialdehyde （MDA） with thiobarbituric acid method. The superoxide dismutase （SOD） activi- ty was determined with the method of Xue Guoxi, peroxidase （POD） with the method of guaiacol, and catalase （CA

关 键 词：核桃 超敏蛋白 低温胁迫 生理指标 

分 类 号：S664.1[农业科学—果树学]