褪黑素预处理对高温下猕猴桃幼苗抗氧化能力的影响  

Effects of Melatonin Application on Antioxidant Capacity in Kiwifruit Seedlings under High Temperature Stress

作　　者：夏惠[1,2] 高帆[1] 胡荣平[3] 吕秀兰[1,2] 梁东[1,2] XIA Hui;GAO Fan;HU Rongping;L Xiulan;LIANG Dong(College of Horticulture,Sichuan Agricultural University,Chengdu 611130,China;Institute of Pomology and Olericulture,Sichuan Agricultural University,Chengdu 611130,China;Institute of Plant Protection,Sichuan Academy of Agricultural Sciences,Chengdu 610066,China)

机构地区：[1]四川农业大学园艺学院,成都611130 [2]四川农业大学果蔬研究所,成都611130 [3]四川省农业科学院植物保护研究所,成都610066

出　　处：《西北植物学报》2019年第8期1425-1433,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：四川省科技支撑计划(2016NZ0105)

摘　　要：为了探明外源褪黑素对高温胁迫下猕猴桃幼苗耐热性的影响,以盆栽‘秦美’猕猴桃幼苗为材料,进行根灌褪黑素溶液和45℃高温胁迫处理,并测定相关抗逆生理指标。结果表明:(1)与高温对照相比,褪黑素预处理显著降低了猕猴桃幼苗叶片相对电导率和丙二醛含量,提高了脯氨酸含量以及过氧化氢酶和过氧化物酶活性,且褪黑素溶液浓度在100~200μmol·L^-1时效果较好。(2)褪黑素预处理显著增加了叶片中总酚、总黄酮和总黄烷醇含量,且幼苗的抗氧化能力(ABTS法、FRAP法和DPPH法)在胁迫过程中显著高于高温对照。研究认为,外源褪黑素可以通过提高植株体内抗氧化酶活性,非酶抗氧化物质如酚类物质和类黄酮物质含量以及渗透调节物质含量来增强植物的抗氧化能力,从而有效缓解高温对于猕猴桃幼苗的伤害,增强猕猴桃幼苗的耐热性。To investigate the effect of exogenous melatonin on heat tolerance in kiwifruit seedlings under high temperature stress,we used the potted seedlings of Actinidia deliciosa cv.Qinmei as materials pretreated with melatonin solution by root irrigating,then under 45℃ heat treatment to determine the physiological indexes of resistance.Results showed that:(1)melatonin pretreatment significantly reduced the relative electrical conductivity level and malondialdehyde content in the leaves of the kiwifruit seedling,and significantly increased the proline content,catalase activity and peroxidase activity when compared with high temperature control.And the best effect was observed when the concentration of melatonin solution was at 100~200μmol·L^-1.(2)Melatonin pretreatment significantly increased the contents of total phenols,total flavonoids and total flavanols,and improved antioxidant capacity assayed by three methods(ABTS,FRAP,DPPH).In summary,melatonin can improve the antioxidant capacity of plants by increasing the contents of phenols and flavonoids,so as to effectively alleviate the damage of high temperature to kiwi seedlings and improve the heat resistance.

关 键 词：褪黑素 猕猴桃 高温胁迫 酚类 类黄酮 抗氧化能力 

分 类 号：Q945.79[生物学—植物学]