乙烯在杜鹃花耐热机制中的作用研究  

Research on the Effect of Ethylene in Heat Resistance Mechanism of Rhododendron

作　　者：赵晖 耿兴敏[1] 王露露 许世达 ZHAO Hui;GENG Xingmin;WANG Lulu;XU Shida(College of Landscape Architecture,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京林业大学风景园林学院,南京210037

出　　处：《园艺学报》2022年第3期561-570,共10页Acta Horticulturae Sinica

基　　金：江苏高校品牌专业建设工程项目(PPZY2015A063);贵州科技支撑项目([2020]4Y028)。

摘　　要：以2个杜鹃花品种‘胭脂蜜’和‘红月’为试验材料,分析了高温胁迫下杜鹃花乙烯释放速率的变化;通过叶面预喷施乙烯利和乙烯合成抑制剂(硝酸钴)溶液,分析预处理对杜鹃花在高温胁迫下的形态变化、叶片MDA、H2O2含量、超氧阴离子产生速率以及抗氧化酶(SOD、POD和CAT)活性等的影响。结果显示:高温胁迫下杜鹃花叶片乙烯合成关键酶ACS和ACO的活性增加,内源乙烯释放速率提高,并且耐热品种‘胭脂蜜’ACS和ACO酶活性和乙烯释放速率均高于热敏感品种‘红月’。100μmol·L^(-1)乙烯利喷施预处理提高了高温胁迫下杜鹃花叶片SOD、POD和CAT酶活性,降低了‘红月’H2O2含量和超氧阴离子产生速率,减轻了过氧化损伤程度;1 000μmol·L^(-1)硝酸钴预处理与100μmol·L^(-1)乙烯利预处理作用相反。结果表明,乙烯在杜鹃花耐热适应性中发挥着重要作用,外源乙烯和乙烯合成抑制剂可以通过调控抗氧化系统影响杜鹃花耐热性。In order to elucidate the heat resistance mechanism of rhododendron seedlings induced by ethylene,in this study two Rhododendron cultivars,’Yanzhimi’and’Hongyue’,were used as experimental materials to analyze the effects of heat stress on the ethylene biosynthesis,and the changes of MDA,H2O2content,the superoxide anion production rate and antioxidant enzyme(SOD,POD and CAT)activities in the leaves induced by spraying ethephon and ethylene synthesis inhibitor(cobalt nitrate).The results showed that the enzyme activities of ACC synthase(ACS)and ACC oxidase(ACO)and endogenous ethylene release rate increased in the leaves under heat stress.In addition,the enzyme activities of ACO,ACS and ethylene release rate in the heat-resistant cultivar’Yanzhimi’were higher than those in the heat-sensitive cultivar’Hongyue’.100 μmol·L^(-1) ethephon increased the enzyme activities of SOD,POD and CAT in the leaves under heat stress,reduced H2O2 content,the superoxide anion production rate of’Hongyue’and degree of lipid peroxidation indicated by MDA.The results of spraying 1 000 μmol·L^(-1)cobalt nitrate were contrary to those of spraying 100 μmol·L^(-1) ethephon.These results indicated that ethylene played an important role in the heat tolerance of rhododendron seedlings,and exogenous ethylene and ethylene synthesis inhibitors could affect the heat resistance of rhododendron by regulating antioxidant system.

关 键 词：杜鹃花 乙烯 高温胁迫 乙烯生物合成 抗氧化体系 

分 类 号：S685.21[农业科学—观赏园艺]