山桐子冬芽休眠过程及其生理生化特征

Dormancy Period of Winter Bud of Idesia Polycarpa and Its Physiological and Biochemical Characteristics

为探究山桐子冬芽休眠过程及其生理生化特征,以东京种源山桐子1年生枝条为材料,通过水培,观察不同时间冬芽在25℃条件下的萌发生长情况及可溶性糖、可溶性蛋白、过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)、生长素(IAA)、脱落酸(ABA)、反式玉米素(tZR)和赤霉素(GA_(3))的含量及活性的变化。结果表明:郑州气候条件下,9—10月为山桐子芽休眠导入期,11月进入深休眠期,12—2月为休眠解除期,3月进入内生长期。在山桐子冬芽休眠过程中,可溶性糖和可溶性蛋白含量从休眠导入期到深休眠期,不断累积随着温度的降低而积累,在深休眠期达到最大,可溶性糖含量在深休眠后期显著高于其他阶段,之后开始下降,而可溶性蛋白含量在进入深休眠期迅速下降,之后随着休眠的解除可溶性蛋白含量先上升再下降然后再上升;抗氧化酶POD和CAT活性呈“下降-上升”的变化趋势,POD活性在进入深休眠期时显著低于其他阶段,而CAT活性在进入深休眠期和休眠解除后期显著低于其他阶段;内源激素IAA和ABA含量在山桐子冬芽休眠导入期都从较低水平呈上升趋势,在进入深休眠期时含量显著高于其他阶段,之后IAA和ABA含量开始下降,而GA_(3)和tZR的含量在进入深休眠期和内生长后期含量显著高于其他阶段,GA_(3)和tZR的含量在深休眠期达到较高水平后开始下降,在12月15日降至最低后开始呈上升趋势。山桐子冬芽随着温度的降低,ABA的相对含量逐渐提高,促进了冬芽的休眠,而随着休眠的加深,冬芽的抗氧化能力逐渐减弱,进入休眠解除期,GA_(3)和tZR的相对含量逐渐提高,加速了芽休眠解除的进程,而随着休眠的解除,冬芽的抗氧化能力得到提升。

In order to investigate the dormancy process of Idesia polycarpa winter buds and its physiological and biochemical characteristics,we observed the sprouting growth of 1-year-old branches of Ⅰ.polycarpa from Tokyo povenance winter buds and the content and activity of physiological and biochemical substances through hydroponically dormant branches at 25℃ during different periods of time,including soluble sugar,soluble pro-tein,catalase(CAT),peroxidase(POD),superoxide dismutase(SOD),auxin(IAA),abscisic acid(ABA)and trans changes of content or activity of zeatin(tZR)and gibberellin(GA_(3)).The results showed that under the climatic conditions in Zhengzhou,the dormancy introduction period for the Ⅰ.polycarpa buds in September-October,the deep dormancy period in November,the dormancy release period in December-February,and the inner growth period in March.In the dormancy process of Ⅰ.polycarpa winter buds,the contents of soluble sugar and soluble protein accumulated from the dormancy introduction stage to the deep dormancy stage,and reached the maximum at the deep dormancy stage.The content of soluble sugar was significantly higher at the late stage of deep dormancy than at other stages,then began to decline,and the soluble protein content rapidly decreased after entering the deep dormancy period,and then the soluble protein content increased first,then decreased,and then increased with the release of dormancy;the activity of antioxidant enzymes POD and CAT showed a'decreasing-rising'trend.The activity of POD was significantly lower when entering the deep dormancy period,while the activity of CAT was significantly lower than that of other stages;the content of endogenous hormones IAA and ABA showed an upward trend from a lower level during the dormancy introduction period of Ⅰ.Polycarpa winter buds.When entering the deep dormancy period,the content was significantly higher than other stages,and then decreased.The content of GA_(3) and tZR were significantly higher than that of other stages during the deep dormancy period and the late ingrowth period.The content of GA_(3) and tZR began to decline after reaching a high level during the deep dormancy period,and then began to increase after reaching a minimum on December 15.With the decrease of temperature,the relative content of ABA in Ⅰ.polycarpa winter buds gradually increased,which promoted the dormancy of winter buds.With the deepening of dormancy,the antioxidant capacity of winter buds gradually decreased.The relative contents of GA_(3) and tZR increased gradually in dormancy release period,which accelerated the process of dormancy release.With the release of dormancy,the antioxidant capacity of winter buds was improved.