赤霞珠葡萄休眠及萌发过程中的氮素代谢

 【目的】探索赤霞珠葡萄在自然休眠期间不同部位不同器官的氮素代谢规律。【方法】以杨凌地区酿酒葡萄品种赤霞珠为试材，对其自然休眠及萌发过程中冬芽、韧皮部、木质部和根部中含氮化合物及氮素代谢相关酶活性的变化进行研究，测定氮化物、总氮含量、总蛋白含量、可溶性蛋白质含量、氮素代谢相关酶活性、硝酸还原酶活性、蛋白酶活性等指标，并对葡萄各器官休眠期的蛋白质进行SDS-PAGE电泳分析。【结果】总氮、总蛋白和可溶性蛋白质在葡萄不同部位的含量高低为：冬芽＞根＞韧皮部＞木质部，冬芽中的总氮和总蛋白在萌芽时显著上升；可溶性蛋白质在葡萄不同部位的趋势为休眠期逐渐下降，萌发期渐渐上升。葡萄休眠过程中，不同器官的硝酸还原酶（NR）活性为冬芽＞根部＞韧皮部＞木质部，从休眠期到萌发期，各部位的硝酸还原酶活性均呈现下降趋势。在葡萄各器官中，冬芽的谷氨酰胺合成酶（GS）活性最高，在生理休眠期活性降到最低；冬芽中谷氨酰胺合成酶的活性变化的总趋势为上升，并出现了两个峰值。在休眠初期，蛋白酶的活性随休眠的加深而降低，随休眠的解除和萌发的进行而升高（除冬芽外）；在葡萄休眠期检测到大量蛋白质。【结论】在赤霞珠葡萄自然休眠和萌发过程中，冬芽、一年生枝韧皮部、木质部及根系中的含氮化合物含量、种类和酶活性在休眠前后发生变化。

Studies on the Nitrogen Metabolism in the Process of Dormancy and Germinating of Cabernet Sauvignon Grapevine

【Objective】 The research is to study the nitrogen metabolism in Cabernet Sauvignon during the period of dormancy. 【Method】Taking Cabernet Sauvignon as experimental materials, this research was conducted to investigate the variation of nitrogenous compounds and relative enzymatic activity in the buds, phloem and xylem of one-year-old cane, and roots during the period of dormancy induction and release in Yangling region. Measure the indexes of the nitrides, total nitrogen, total protein, soluble protein content, nitrogen metabolism-related enzyme activity, nitrate reductase activity, protease activity were determined, and the proteins in various grape organs at dormant phase were analyzed by using SDS-polyacrylamide gel electrophoresis.【Result】The contents of total nitrogen , protein and soluble protein in different parts of grape from high to low were buds＞roots＞phloem＞xylem，especially total nitrogen and protein in buds increased obviously. Contents of soluble proteins decreased gradually during the dormant induction, and increased gradually during the dormant release. Nitrate reductase activity of different dormant organs or tissues from high to low were buds＞roots＞phloem＞xylem. From dormancy to germinating stage, nitrate reductase（NR）activity generally decreased. In different organs of grapevine, glutamine synzyme activity in buds was maximal, during the period of deep dormancy, the glutamine synzyme activity was lowered to a minimum, the general trend of glutamine synzyme activity in buds was rising with two peaks during the dormant period. In the early dormancy, protease activity decreased with the deepening of sleep, and increased with the lifting of dormancy and germination (except buds). A large number of proteins emerged in the period of grape dormancy.【Conclusion】The buds, one-year old canes phloem, xylem and nitrogen compounds content, type and enzyme activity of the root changed before and after dormancy in the natural process of dormancy and germination.