核桃主要器官氮素含量及分配的动态变化规律

对核桃主要器官中氮素含量及器官间氮素的分配比例的动态变化规律进行了研究。结果表明:氮素在核桃各器官中的变化规律与其自身的生长规律相吻合,在整个生育期中,以树体萌芽期各营养器官的氮素含量最高,雌花或幼果的氮素含量也相对较高;在枝条旺盛生长及果实的速长期,各主要器官的氮素含量呈下降趋势;在核桃种仁充实期,果实中的氮素含量急剧上升,而叶片和枝条中的氮素含量继续下降。不同生育期主要器官间氮素的分配比例有差异,5月中旬至7月上旬氮素的分配比例排序为叶片>果实 >果枝>营养枝;7月中旬至9月上旬氮素的分配比例排序为果实>叶片>果枝>营养枝。

Dynamic Change Laws of the Content and Distribution of Nitrogen in the Main Organs of Walnut

The change laws of the contents of nitrogen in main organs of walnut and the distribution of nitrogen in the organs at different growth and development stages were studied. The results showed that the change laws of the contents of nitrogen in the main organs were corresponded with the annual growth and development cycle of walnut tree. The contents of nitrogen in nutritive organs were the highest, and that in female flowers or young fruits was also higher in all organs researched in the whole growth and development stage. The contents of nitrogen in all organs were decreased during the rapid growth phase of neonatal branches and fruit. In the rapid growth phase of nucleolus, the contents of nitrogen in fruit were increased sharply, while that in leaves and shoots kept on being decreased. The distribution ratio of nitrogen in main organs were different in the different growth and development phases, for example, the order of the distribution ratio of nitrogen among the organs was leaf>fruit>fruit shoot> vegetative branch from the middle ten days of May to the first ten days of July, and the order was fruit>leaf>fruit shoot>vegetative branch from the middle ten days of July to the first ten days of September.