杨为海　曾辉　万继锋　张汉周　陆超忠

摘  要：為探明高温条件下澳洲坚果叶片黄化的生理特性，以澳洲坚果品种‘HAES344的叶片为试材，对湛江地区2019年6月份的气温进行调查，初步研究叶片的一些生理生化指标的变化。结果表明：湛江地区6月份的昼/夜平均温度高达33.6 ℃/28.5 ℃，特别是遭遇了3次较长时间的温度高峰期，其每日的昼/夜平均温度均超过35 ℃/29 ℃，可能导致了黄化叶片发生。随着叶片黄化程度的加深，叶片的SPAD值、SOD活性以及叶绿素（Chla+Chlb、Chla与Chlb）含量及其荧光参数（Fo、Fm与Fv / Fm）均显著下降，而丙二醛（MDA）和过氧化氢（H2O2）含量以及POD活性均显著升高，CAT活性则保持相对稳定。但同正常叶片相比，黄化叶片的SPAD值、叶绿素含量及其荧光参数均显著降低，而MDA和H2O2含量以及POD与CAT活性却显著升高。相关性分析结果表明，Fo、Fm、Fv / Fm、MDA、Chla、CAT、SOD、POD等8个指标间存在一定的显著相关性。该结果对于了解澳洲坚果叶片黄化具有参考价值，为进一步开展相关分子机理研究奠定了基础。

关键词：澳洲坚果;高温;叶片黄化;叶绿素荧光

中图分类号：S667.9      文献标识码：A

Preliminary Study on Physiological Characteristics of Macadamia Leaf Etiolation under High Temperature

YANG Weihai1， ZENG Hui2，3， WAN Jifeng2，3， ZHANG Hanzhou2，3， LU Chaozhong2，3*

1. College of Life Science and Resources and Environment， Yichun University， Yichun， Jiangxi 336000， China; 2. South Subtropical Crops Research Institute， Chinese Academy of Tropical Agricultural Sciences， Zhanjiang， Guangdong 524091， China; 3. Key Laboratory of Tropical Fruit Biology， Ministry of Agriculture and Rural Affairs， Zhanjiang， Guangdong 524091， China

Abstract： In order to find the physiological characteristics of macadamia leaf etiolation under high temperature， taking the leaves of ‘HAES344 macadamia as the test materials， the trial studied the temperature of June， 2019 in Zhanjiang area， and the changes of several related physiological indexes in the leaves were preliminarily investigated. The results showed that the average day/night temperature in June was as high as 33.6 ℃/28.5 ℃， especially the three long temperature peaks whose daily day/night average temperature exceeded 35 ℃/29 ℃， which probably caused the yellowing of the leaves. With the intensification of leaf etiolation， the SPAD value， SOD activity， chlorophyll （Chla+Chlab， Chla and Chlb） content and its fluorescence parameters （Fo， Fm and Fv / Fm） of the leaves decreased significantly， while the contents of malondialdehyde （MDA） and H2O2 and the activity of POD increased obviously， but the CAT activity remained relatively stable. However， compared with normal leaves， the SPAD value， chlorophyll content and fluorescence parameters of the etiolation leaves were significantly reduced， while MDA and H2O2 contents and POD and CAT activities significantly increased. The correlation analysis showed that there was a certain significant correlation among Fo， Fm， Fv/Fm， MDA， Chla， CAT， SOD and POD. The results would provide the reference value in understanding the yellowing leaves of macadamia and establishing a foundation for further research on relevant molecular mechanism.

Keywords： macadamia; high temperature; leaf etiolation; chlorophyll fluorescence

DOI： 10.3969/j.issn.1000-2561.2021.03.031

澳洲坚果（Macadamia integrifolia，M. tetraphylla）是我国南亚热带地区新兴的常绿乔木果树，已在我国云南、广西、广东、贵州等省（区）推广种植约200 000 hm2，成为了一个经济与生态效益俱佳的新兴特色产业。然而，随着全球气候变暖，高温对作物生育和产量的威胁已是一个全球性的热点问题[1]。经调查发现，在夏季持续的高温条件下，广东与广西的坚果园中一些耐热性较差的澳洲坚果品种（如‘HAES344‘桂热1号等）的新梢叶片容易发生黄化，甚至失水干枯，影响果实产量，而在贵州与云南产区则少见此类现象。……