在不同条件下杉木伐桩萌芽中几种有机物含量的变异

<正>在南京林业大学下蜀实验林场,按杉木伐桩的全光、半荫、全荫处理,以及林木的环割、不割处理,春季分别取休眠芽(前三者)或侧枝顶芽(后二者)样品,进行有机物含量分析。结果表明,各处理样品中水溶性蛋白质含量差别不大,叶绿素含量亦都很低,但休眠芽中的水溶性糖含量比顶芽中要低得多。伐桩萌芽的含糖量并不与各处理条件下的光照和温度呈正相关关系;但伐桩上萌芽数目增多,则含糖量相应下降,表现为幂函数曲线关系。考虑到这种情况,以及幼芽内叶绿素含量水平很低,因此,可以认为萌芽的糖分主要来自根桩本身的碳水化合物贮藏物,而并非来自光合作用。因此,控制一个代桩上的萌芽数目,是获得健壮萌条的关键措施之一。

VARIATION OF SOME ORGANIC COMPONENTS IN DEVELOPING BUDS FROM CUTTING STOCKS OF CHINESE FIR UNDER VARIOUS TREATMENTS

In Xiashu Forestry Experimental Centre of Nanjing Forestry University, treatments of full illumination,half shade and full shade upon cutting stocks,and of ringing and non-ringing upon tree stems of Chinese fir were assigned, and from which developing bud samples were collected during the spring for analysing the contents of organic components. The results showed that the contents of water-soluble protein in the samples from various treatments were only a little different, and all their contents of chlorophyll were very small,but the contents of water-soluble sugar in the developing buds from the cutting stocks were far lower than those from the terminal buds of lateral shoots within the tree crowns. The sugar content in the developing buds from the cutting stocks did not positively correlate with the intensity of illumination and the temperature at ground surface under various shading treatments; but it decreased with the increase of budding number from the stocks, showing a relation of the power function. With these relationships and also the very low level of the chlorophyll content in the developing buds, it was deemed that the sugar content in the developing buds derived from the earbohydrate storage in the cutting stocks, but not from the photosynthesis of the buds. Therefore to control the budding number from a cutting stock was one of the important measures for obtaining healthy and strong sproutings.