水杉苗期对氮素营养需求的研究

Study on Requirement for Nitrogen Nutrition by Seedling of Metasequoia Glyptostroboides

为研究水杉苗对氮素营养的需求 ,按 0 0 ,1 0 ,2 0 ,3 0 ,4 0和 5 0g氮 /盆 6个水平进行试验研究。结果表明 :水杉苗高、地径、分枝数、分枝总长等随着施氮量的增加而提高 ,但当施氮量超过 3 0 g/1 5kg土后 ,这些项目又随施氮量的继续增加而下降。水杉苗叶绿素的含量对氮素的反应亦与此类似 ;根、茎、叶的含氮量随施氮量的增加而增加。

In order to study requirement for nitrogen nutrition by seedling of Metasequoia glyptostroboides,a trial study was conducted according to six application levels of 0.0, 1.0,2.0,3.0,4.0 and 5.0 g nitrogen/pot, the result showed that: 1. seedling height, ground diameter, branching number and its total length raise along with increment in nitrogen application rate, however, these indexes fall down along with the continous increment in nitrogen application rate after excess of 3.0 g/15 kg soil in nitrogen application rate,reaction to nitrogen is similar to these by content of chlorophyll in seedling of Metasequoia glyptostroboides.2. The contents of nitrogen in root, stem and leaf rise along with increment in nitrogen-application rate.