不同光照强度对银叶金合欢幼苗阶段生长的影响

Effects of Different Light Intensity on the Stage Growth of Acacia podalyriifolia Seedling

以银叶金合欢(Acacia podalyriifolia)幼苗为材料,设置3个不同光照处理(分别为林下全光照、70%光照和半光照),测定银叶金合欢的各项生长指标(苗高、地径)、叶片的叶绿素含量及其生物量。结果表明:全光照最有利于苗高和地径生长,在半光照的光照条件下,幼苗生长指标均极低,表明银叶金合欢不耐阴。随着光照强度的减弱,叶绿素含量逐渐增加,半光照的叶绿素含量最高,且与全光照、70%光照条件下的叶绿素含量差异显著。不同遮光度下的银叶金合欢的生物量随着遮光度的增加而降低,在强光照水平下,植株增加了对叶和枝条的生物量分配,在低光照水平下增加了对根的生物量分配,中度光照条件下植株对根和叶枝的分配则处于两者之间。综合各项生长指标(苗高、地径)、叶片的叶绿素含量及其生物量的结果,表明弱光极不利于银叶金合欢幼苗的生长。

Using Acacia podalyriifolia seedlings as the material,different illumination treatments(0%,30%and 50%respectively)were used to determine the growth indexes(seedling height,ground diameter),chlorophyll content and biomass of the leaves of the A.podalyriifolia.The results showed that under the condition of illumination of 50%,the seedling growth index was low under the conditions of 0%,which showed that the A.podalyriifolia was not tolerant to shade.With the decrease of light intensity,the content of chlorophyll increased gradually,the chlorophyll content of 50%under the forest was the highest,and the chlorophyll content was different under the condition of 0%and 30%shading of forest.The biomass of the A.podalyriifolia under different shading was decreased with the increase of shading,at the high light level,the plant increased the biomass distribution of the leaves and branches,and the distribution of the biomass of the roots under the low light level,and the distribution of the roots,leaves and shoots in the medium illumination was between the two.The results of various growth indexes(seedling height,ground diameter),chlorophyll content and biomass of leaves showed that the low light environment was not conducive to the growth of A.podalyriifolia seedlings.