白木香人工结香初期营养元素及叶片叶绿素含量的变化

为了探究白木香（ Aquilaria sinensis ）人工结香初期营养代谢变化规律，明确结香期白木香合理的施肥技术。以4年生白木香为研究对象，以未结香白木香植株为对照，进行人工打洞结香处理，分析结香初期白木香植株叶片、结香部位树皮以及木质部营养元素含量变化，同时测定叶片叶绿素含量变化。结果表明:1. 白木香结香初期叶片中大量元素氮、磷、钾和微量元素铁、锌养分含量呈现减少趋势，钙、镁、铜、锰元素含量上升，但只有锌、锰元素的变化达到差异显著水平；结香部位树皮氮、磷、钙、铁、锌、锰元素含量呈增加趋势，钾、镁、铜元素呈下降趋势，其中铜、铁、锌、锰元素含量变化显著；结香部位木质部氮、磷、钾、钙、镁、铜、铁、锌、锰全部呈现上升趋势，且钙、镁、铜、锰含量变化达到差异显著水平；说明结香初期植株营养元素含量变化与土壤养分相关性不显著。2. 与未结香白木香相比，结香后植株叶片营养元素含量/结香部位木质部营养元素含量比值中，氮、磷、钾、镁、铜、铁、锌元素比值显著下降，而钙、锰比值变化不显著，表明营养元素向结香部位迁移趋势明显。3. 白木香结香后叶片叶绿素含量呈上升趋势，但没有达到差异显著水平。

The Changes of Nutrient and Leaf Chlorophyll Contents of Aquilaria sinensis at the Early Agarwood Inducing Stage

An attempt was made to analyze the metabolic changes of nutrients in Aquilaria sincensis at the early agarwood inducing stage for the development of the fertilizer application method for A. sinensis at the agarwood inducing stage. A. sinensis trees at the age of 4 years old were holed on the stem manually to induce agarwood with the trees without stem holing as control. The nutrient contents of the leaves and the barks and the xylems of the holed stem at the early agarwood inducing stage were determined and the leaf chlorophyll content were measured. The results showed at the agarwood inducing stage the leaf contents of N, P, K, Fe and Zn in A. sinensis decreased, while the leaf contents of Ca, Mg, Cu and Mn increased. Only the leaf contents of Zn and Mn showed a significant change. The bark contents of N, P, Ca, Fe, Zn and Mn increased and the bark contents of K, Mg and Cu decreased, but the change was significant only in the bark contents of Cu, Fe, Zn and Mn. In the xylem the contents of N, P, K, Ca, Mg, Cu, Fe, Zn and Mn all showed an upward trend, of which the contents of Ca, Mg, Mn and Cu showed a significant change. Correlation analysis showed that there was no significant correlation between changes in plant nutrient contents and soil nutrient contents at the early agarwood inducing stage. The ratios of the leaves to the xylem of the trees treated with agarwood inducing were decreased significantly in the contents of N, P, K, Mg, Cu, Fe and Zn and were not significantly changed in the contents of Ca and Mn at the early agarwood inducing stage, as compared with those of the control without agarwood inducing. The leaf chlorophyll content was increased at the early agarwood inducing stage without any significance.