长白山不同针叶树耐阴性的形态适应及内源激素调控

在不同郁闭度的林分内,对红松、红皮云杉、长白落叶松的形态适应性和内源激素水平及其分布状况进行了研究。结果表明,红松耐阴性的形态适应方式主要为促进顶枝生长和增大比叶面积;红皮云杉耐阴性的形态适应方式主要为增加侧枝数量和比叶面积。在弱光条件下,红松顶枝生长旺盛、比叶面积增大与其相应部位内源激素Z含量增加有关;云杉顶叶内源激素ZR含量增加与比叶面积增大有关,侧枝数量增加与分杈部位ABA含量降低有关。3个树种中红松最适合弱光生长.

Morphological plasticity of shade-tolerance of three conifers in Changbai Mountain and regulation of hormone

The morphological plasticity of Pinus koraiensis, Picea koraiensis and Larix olgensis to shade tolerance, and the level and distribution of their endogenetic hormones were studied in forests with different canopy density. The morphological plasticity of Pinus koraiensis to shade-tolerance promoted the growth of apical branches and increased the specific leaf area (SLA); while that of Picea koraiensis benefited the number of lateral branches and SLA. Under low light intensity, the increasing growth of apical branches and the increasing SLA of Pinus korainensis were positively correlated to the content of endogenetic hormone Z in corresponding positions. The content of endogenetic hormone Z R in top leaves of Picea koraiensis was positively correlated with the SLA, and the number of lateral branches was negatively correlated with the content of ABA in bifurcated positions. Among the three conifers, Pinus korainensis was the most suitable to low light intensity.