Acta Horticulturae Sinica ›› 2022, Vol. 49 ›› Issue (3): 561-570.doi: 10.16420/j.issn.0513-353x.2021-0013

• Research Papers • Previous Articles     Next Articles

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

ZHAO Hui, GENG Xingmin*(), WANG Lulu, XU Shida   

  1. College of Landscape Architecture,Nanjing Forestry University,Nanjing 210037,China
  • Received:2021-05-07 Revised:2021-12-17 Online:2022-03-25 Published:2022-03-25
  • Contact: GENG Xingmin


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,H2O2 content,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-1ethephon. 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.

Key words: Rhododendron, ethylene, high temperature stress, ethylene biosynthesis, antioxidant systems

CLC Number: