短枝木麻黄小枝单宁对其幼苗生长及单宁含量的效应

Effects of Tannin Extracted from Casuarina equisetifolia Branchlets on the Growth and Tannin Contents of Its Seedlings

摘要:

以短枝木麻黄(Casuarina equisetifolia)小枝中提取的单宁处理其幼苗，探讨其化感作用及其对幼苗单宁含量的影响。结果表明，单宁对木麻黄幼苗的生长有显著抑制作用，且随着处理浓度的升高，抑制作用逐渐增强，处理15 d后，单宁的化感作用对芽长的抑制程度显著高于根长。单宁处理后，幼苗体内单宁含量也发生显著变化，随着处理浓度的升高而逐渐降低，尤其是总酚和可溶性缩合单宁的含量，单宁溶液的浓度与被处理幼苗体内单宁含量间有显著的线性负相关。因此，短枝木麻黄体内的单宁会对同种的幼苗产生化感作用，这种化感作用不仅影响幼苗的生长和发育，也会通过影响幼苗体内次生代谢物质的形成而影响幼苗对食草动物和其他不利因素的抵抗能力。

Abstract:

Effects of tannin extracted from Casuarina equisetifolia branchlets on the growth and tannin contents of its seedlings were studied. The tannins extracted from C. equisetifolia branchlets significantly inhibited the seedling growth, and the inhibition enhanced with increasing of tannin concentration. Under the same concentrations of tannins, sprout growth was inhibited more significantly than root growth treated after 15 days. The contents of tannins, especially total phenolics and extractable condensed tannins in seedlings decreased with increasing of extracted tannin concentrations. The significant linear negative correlation between them demonstrated that tannins extracted from C. equisetifolia branchlets had significant allelophthic effects on the seedlings. The allelophthic effects impacted not only the growth of C. equisetifolia seedlings, but also resistance against herbivore and other detrimental factors through impacting the formation of secondary metabolites in seedlings.