毛竹实生苗氮素吸收与分配利用特征研究

[Objective]To explore the distribution and utilization of nutrients in the growth process of Phyllostachys pubescens(Phyllostachys edulis)at seedling stage,so as to provide scientific basis for guiding precise fertilization and sustainable management of Moso bamboo forest.[Methods]Under the condition of nitrogen starvation,the clonal ramet(one year plant)and clonal ramet(2-year-old plant)of Phyllostachys pubescens seedlings were labeled with urea-15N respectively,and the nitrogen heterogeneity treatment was carried out by 15N isotope tracer technique.the distribution and utilization of N among clonal ramets were analyzed.[Results]The absorption,distribution and utilization of 15 N in the clone system of Phyllostachys pubescens seedlings were consistent.1)When the annual bamboo was labeled with 15N,the absorption,distribution and utilization of nitrogen in each organ of the cloning system were 15N bamboo whip root>15N mother bamboo whip root>15N bamboo leaf>15N bamboo whip = 15N bamboo whip>15N bamboo branch>15N bamboo culm>mother bamboo leaf>mother bamboo branch>mother bamboo stalk>bamboo leaf = bamboo whip = gt Bamboo branch = bamboo stalk>bamboo whip root>mother bamboo whip root>mother bamboo whip root 2)When the biennial mother bamboo was labeled with 15N,the absorption,distribution and utilization of nitrogen in each organ of the clone were as follows:15N mother bamboo whip>15N mother bamboo whip root>15N mother bamboo leaf>leaf>15N mother bamboo whip root>bamboo whip>15N mother bamboo culm>bamboo whip root>bamboo branch>bamboo stem.[Conclusion]The clonal integration of Phyllostachys pubescens had obvious law of"transport to the top"and age effect.the absorption,distribution and utilization of nitrogen in the whole clonal system of 1-year-old daughter bamboo was higher than that of 2-year-old mother bamboo only,and both of them were more beneficial to the absorption,distribution and utilization of nitrogen than uniform fertilization in the whole clonal system.Therefore,in real life,we can choose to spray leaf fertilizer to weaken the law of"Transport to the top"and enhance the nutrient absorption of bamboo culms;at the same time,only fertilizing 1-year-old son bamboo can most effectively reduce the amount of fertilizer use.improve the fertilizer utilization rate of the whole cloning system.