不同需冷量枣品种休眠期间糖组分含量及相关酶活性变化规律

Change Rule of Sugar Component Content and Related Enzymes Activities of Jujube Cultivars with Different Chilling Requirements during Dormancy

为探究不同需冷量枣品种休眠期间糖积累特性及代谢相关酶活性的变化规律,筛选出影响枣树休眠的关键物质以为枣树休眠生理机制研究提供理论依据,本试验以高需冷量品种‘胎里红’、中需冷量品种‘伏脆蜜’、低需冷量品种‘京枣39’共3个枣品种为材料,研究分析休眠过程中枣枝条碳水化合物含量、相关代谢酶活性的变化及其与休眠的关系。结果表明,枣树休眠期间枝条中可溶性糖含量最高,在0.40%~1.28%之间,其次是蔗糖、葡萄糖、果糖含量。3个不同需冷量枣品种中,京枣39枝条蔗糖含量于11月12日达到峰值,为0.63%,伏脆蜜、胎里红均于11月19日达到峰值,分别为0.45%、0.36%;京枣39于12月24日蔗糖含量下降到谷值,为0.11%,伏脆蜜于12月31日下降到谷值,为0.05%,胎里红于1月7日下降到谷值,为0.08%。蔗糖含量峰值和谷值对应着进入休眠和解除休眠的时间点,表明蔗糖含量随休眠的进程而变化。京枣39、伏脆蜜、胎里红中性转化酶(NI)活性均于11月19日升到峰值,分别为20.02、15.60、16.73μmol·g^(-1)·min^(-1);京枣39的NI活性于12月24日降到谷值,为12.60μmol·g^(-1)·min^(-1),伏脆蜜于12月31日降到谷值,为12.34μmol·g^(-1)·min^(-1),胎里红于1月7日降到谷值,为11.36μmol·g^(-1)·min^(-1)。与蔗糖含量变化趋势一致,休眠前NI活性呈上升趋势,进入休眠后开始下降,休眠解除后呈上升趋势并且产生的谷值对应着解除休眠的关键时间点。综上看出,枣树休眠过程中碳水化合物的积累以可溶性糖为主,蔗糖是影响枣树休眠的关键物质,其含量的变化会影响枣树休眠的进程,且中性转化酶是枣树休眠过程中糖分积累的关键酶。

In order to explore the change rule of sugar accumulation and metabolism-related enzymes ac-tivities during dormancy of different jujube varieties with different chilling requirement,screen out key substances affecting jujube tree dormancy and provide a theoretical basis for studying physiological mechanisms of jujube tree dormancy,this experiment was conducted using three jujube varieties of Tailihong with high chill-ing requirement,Fucuimi with medium chilling requirement,and Jingzao 39 with low chilling requirement as materials to analyze the changes of carbohydrate content and related metabolic enzymes activities of jujube shoots during dormancy and their relationship with dormancy.The results showed that the soluble sugar content in jujube branches during dormancy was the highest,ranging from 0.4%to 1.28%,followed by sucrose,glu-cose and fructose contents.Among the three jujube varieties,the sucrose content in Jingzao 39 branches reached the peak value of 0.63%on November 12,and that of Fucuimi and Tailihong reached the peak value on November 19,which was 0.45%and 0.36%,respectively.The sucrose content of Jingzao 39 dropped to the valley value of 0.11%on December 24,while that of Fucuimi dropped to the valley value of 0.05%on Decem-ber 31,and that of Tailihong dropped to the valley value of 0.08%on January 7.It could be seen that the peak and valley values of sucrose content corresponded to the time entering and releasing dormancy,which reflected that sucrose content changed with the process of dormancy.The neutral invertase(NI)activity of Jingzao 39,Fucuimi and Tailihong increased to the peak value on November 19,which were 20.02,15.60 and 16.73μmol􀅰g^(-1)·min^(-1),respectively.The NI activity of Jingzao 39 dropped to the valley value of 12.60μmol􀅰g^(-1)·min^(-1) on December 24,while that of Fucuimi decreased to the valley value of 12.34μmol􀅰g^(-1)·min^(-1) on De-cember 31,and that of Tailihong decreased to the valley value of 11.36μmol􀅰g^(-1)·min^(-1) on January 7.In line with the change trend of sucrose content,NI activity increased before dormancy,began to decline after ente-ring dormancy,and increased after dormancy was released;the generated valley value corresponded to the key time of dormancy release.In summary,the carbohydrates accumulation during the dormancy of jujube trees was mainly soluble sugar;sucrose was the key substance affecting jujube tree dormancy;the change of its con-tent would affect the process of jujube tree dormancy,and neutral invertase was the key enzyme for sugar accu-mulation during jujube tree dormancy.