越冬期软枣猕猴桃田间冻害调查及抗寒生理

Field Freezing Injury Investigation and Physiological Characteristics of Cold Resistance of Actinidia arguta During Overwintering

以五年生软枣猕猴桃品种‘魁绿’‘丰绿’和‘96-6’为试材,采用田间调查和比较分析的方法,研究了自然越冬期间3种软枣猕猴桃的田间冻害情况及其一年生枝条含水量、渗透调节物质含量及保护酶活性的变化,明确不同品种软枣猕猴桃对低温的适应能力及其内在的生理机制,以期为东北地区软枣猕猴桃抗寒品种的选育提供参考依据。结果表明:根据田间冻害调查和冻害指数可以判断出,3种软枣猕猴桃的抗寒性强弱顺序依次为‘魁绿’>‘96-6’>‘丰绿’。随着冬春季节气温的先降低后升高,软枣猕猴桃一年生枝条内的组织含水量呈先降低后升高的趋势,束缚水/自由水比值、可溶性糖含量、可溶性蛋白质含量、游离脯氨酸含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性均表现出不同程度的先升高后降低。综上所述,在自然越冬的各个时期,‘魁绿’的各项生理指标值在3个供试品种中最高,‘丰绿’的最低,‘96-6’处于二者之间,这与各品种的抗寒性强弱顺序一致。

The 5-year-old Actinidia arguta varieties ‘Kuilyu’ ‘Fenglyu’ and ‘96-6’ were used as the test materials to study the effects of cold stress on the internal physiological mechanism of different varieties of Actinidia arguta during the overwintering through field investigation and comparative analysis.The field freezing injury was investigated and the changes of the water content, osmotic adjustment substances content and protective enzymes activities of the annual branches were determined, in order to provide a theoretical reference for the selection and breeding of cold-resistant Actinidia arguta varieties in the Northeast of China.The results showed that the cold resistance capacity of the three Actinidia arguta varieties was as followed, ‘Kuilyu’>‘96-6’>‘Fenglyu’,according to the field freezing injury investigation and the freezing injury index.As the temperature decreased first and then increased during the overwintering period, the tissue water content in the annual branches decreased first and then increased.Bound water/free water rate, soluble sugar content, soluble protein content, proline content, superoxide dismutase(SOD) activity, peroxidase(POD) activity and catalase(CAT) activity showed a trend of first rising and then falling in varying degrees.The study found that, every physiological characteristic of ‘Kuilyu’ was the highest among the three varieties during the whole overwintering period.‘Fenglyu’ was the lowest one and ‘96-6’ was in between.It was consistent with the order of cold resistance capacity of these three Actinidia arguta varieties.