自然越冬期软枣猕猴桃枝条组织结构及内源激素的变化特征

该试验以抗寒性不同的5年生软枣猕猴桃品种‘魁绿’、‘丰绿’和‘96-6’为试验材料,测定分析自然越冬期间枝条组织解剖结构、细胞膜透性和内源激素GA3、ABA、IAA含量水平的变化,以明确不同品种软枣猕猴桃越冬期间对低温的适应能力及其内在生理机制,为软枣猕猴桃抗寒品种的选育及鉴别提供理论依据。结果表明:(1)软枣猕猴桃枝条木质部比率大小依次为‘魁绿’>‘96-6’>‘丰绿’,皮层比率依次为‘丰绿’>96-6’>魁绿’,二者表现趋势相反,且‘魁绿’枝条的解剖结构与其他两品种差异显著。(2)在自然越冬期间,各品种软枣猕猴桃枝条相对电导率和MDA含量随温度变化均呈先升后降的趋势,在温度最低的1月份达到最高,其中‘魁绿’枝条的相对电导率和MDA含量变化幅度最小,而‘丰绿’受低温影响较大。(3)在11月份至2月份,随自然温度的变化,各品种软枣猕猴桃枝条的GA3和IAA含量均呈先降低后升高的变化趋势,ABA含量则呈先升后降的趋势,且都在1月份分别达到最低或最高值。研究发现,在自然越冬期间,低温对3个软枣猕猴桃品种的组织解剖结构、膜透性及内源激素含量均都造成较大的影响,品种‘魁绿’枝条的木质部比率最大、皮层比率最小,相对电导率和MDA含量变化幅度最小,内源激素含量GA3和ABA/GA3变化趋势较小,故其抗寒性比‘丰绿’和‘96-6’更强。

Changes in Tissue Structure and Endogenous Hormones of Actinidia arguta Branches during Over wintering Period

By comparing the differences in tissue anatomy,membrane permeability,and endogenous hormones of different varieties of jujube kiwifruit during the natural wintering period,we investigated the adaptability of kiwifruit to low temperature in order to provide a theoretical reference for the selection and identification of cold-resistant kiwifruit varieties.The five-year-old kiwifruit cultivars‘Kuilv’,‘Fenglv’and‘96-6’were used to determine the changes in anatomical structure of shoot tissue,cell membrane permeability and endogenous hormones such as GA3,ABA,and IAA during the winter.We hope to determine the low-temperature adaptability and its underlying mechanism of different varieties of kiwifruit.The result shows:(1)the xylem ratio from big to small is:‘Kuilv’,‘96-6’and‘Fenglv’,and the cortex ratio is‘Fenglv’,‘96-6’and‘Kuilv’.The anatomy of‘Kuilv’is significantly different from the other two varieties.(2)The relative electrical conductivity and MDA content of kiwifruit showed a trend that firstly increased and then decreased when temperature changes,and reached the highest in January that the temperature was the lowest.Among them,‘Kuilv’has the smallest change,and‘Fenglv’is affected by low temperature.(3)As the temperature dropped,GA3 and IAA content gradually decreased,and ABA content gradually increased from November to January.With the change of natural temperature from November to February,the contents of GA3 and IAA both decreased firstly and then increased,reaching the lowest value in January,and the ABA content increased firstly and then decreased,reaching a peak in January.Low temperature has a significant impact on the tissue anatomy,membrane permeability and endogenous hormones of three A.arguta varieties.Variety‘Kuilv’has the largest ratio of xylem and smallest ratio of cortex,and the smallest change in relative conductivity and MDA content.The endogenous hormone content GA3 and ABA/GA3 have a smaller change trend,so their cold resistance is stronger than that of‘Fenglv’and‘96-6’.