低温胁迫下8种柑橘的生理响应与抗寒性评价

本研究比较了8个柑橘品种的抗寒性并对其进行综合评价,以期了解这8种柑橘的抗寒能力差异并筛选评价柑橘抗寒能力差异的关键指标,这不仅为评价柑橘抗寒性提供了重要参考指标,也为柑橘的扩大引种和栽培提供了依据。以8种柑橘离体枝条为材料,分析0℃、-2℃和-4℃时柑橘的形态和生理生化指标的变化,通过隶属函数综合比较8种柑橘的抗寒能力,同时利用主成分分析法筛选评价柑橘抗寒能力差异的关键指标。结果表明:随着处理温度的逐渐降低,8种柑橘叶片均出现了卷曲、失水、冻斑的现象,同时最大光化学效率(F_v/F_m)、叶绿素a(Chl a)、叶绿素b(Chl b)、类胡萝卜素、丙二醛(MDA)含量和相对含水量均呈现显著降低趋势,相对电导率(REC)值呈显著升高趋势,脯氨酸(Pro)和可溶性糖含量呈先升高后降低趋势。隶属函数分析表明,8种柑橘的抗寒能力大小依次为‘南丰蜜桔’>‘华农冰糖’>‘朱红桔’>‘日南1号’>‘椪柑’>‘本地早’>‘千山红’>‘温州蜜柑’。主成分分析表明,REC与主成分的相关系数达到了0.931,可以作为今后评价柑橘抗寒性的主要参考指标。

Physiological Response and Cold Resistance Evaluation of Eight Species of Citrus under Low Temperature Stress

In this study,the cold resistance of eight Citrus varieties was compared and comprehensively evaluated,in order to understand the differences of cold resistance of these eight Citrus varieties and to screen the key indexes for evaluating the differences of cold resistance of Citrus.This not only provides important reference indexes for evaluating the cold resistance of Citrus,but provides a basis for expanding the introduction and cultivation of Citrus.Eight kinds of Citrus were used as experimental materials,and their detached branches were treated at 0℃,-2℃and-4℃to analyze changes of the morphological,physiological and biochemical indexes of Citrus.Meanwhile the method of subordinate function was used to comprehensive compare the cold resistance abilities of eight kinds of Citrus and meanwhile the principal components analysis was also chosen to screen the key indexes to evaluate the difference of Citrus cold resistance.The results showed that eight varieties of Citrus leaves exhibited different degree leaf curl,water loss and frost spots phenomenon with the gradual decrease of treatment temperature.The indexes of maximum photochemical efficiency(F_v/F_m),chlorophyll a(Chl a),chlorophyll b(Chl b),carotenoids,malondialdehyde(MDA)and relative water content all showed a significant decrease trend in eight varieties of Citrus with the gradual decrease of treatment temperature.Relative electric conductivity(REC)value showed a significant increase trend and proline(Pro)and soluble sugar contents both showed an increasing trend at first and then decreasing compared with the control groups.The analysis of the subordinate function showed that the orders of the cold resistance of Citrus from strength to weakness were’Nanfengmiju’>’Huanongbingtang’>’Zhuhongju’>’Nichinan1’>’Ponkan mandarin’>’Bendizao’>’Qianshanhong’>’Satsuma orange’.Principal component analysis showed that the correlation coefficient between REC and principal component reached 0.931,which can be used as the main reference index for evaluating the cold resistance of Citrus in the future.