紫茎泽兰对桉树的化感作用

Allelopathic Effects of Eupatorium adenophorum(Spreng.) on Eucalyptus

为了探索紫茎泽兰对桉树的化感作用,研究分析了紫茎泽兰叶片浸出液及枯落物对直杆桉苗生长的影响,同时结合紫茎泽兰对桉树人工林的入侵情况,初步研究了紫茎泽兰对桉树的化感作用。结果表明:紫茎泽兰可以成为桉树人工林地上的单优势种群,提高桉树人工林地的土壤含水率,但会影响到桉树的健康状况。紫茎泽兰叶片浸出液对直杆桉苗地上部分和地下部分化感作用相反,对地上部分表现出一定的抑制作用,对地下部分根系表现出较好的促进作用,提高了根系的恢复能力,而枯落物基质浇浸出液对根系的促进效果最佳。在红壤和枯落物基质中,浸出液处理次数与根系生长均呈极显著正相关。

The allelopathic effects of Eupatorium adenophorum （Spreng.） leaf extract and litter on Eucalyptus maidenii seedling growth were examined in this study. This was complemented by field studies on the allelopathic effects of E. adenophorum intrusions in Eucalyptus plantations. The results showed that the E. adenophorum can become the single dominant understory species in Eucalyptus plantations, and whilst it can improve soil moisture content it does adversely affect the health of Eucalyptus. E. adenophorum leaf extracts were found to have contrary effects on the above-ground and under-ground parts of eucalypt trees;in situ leachate from the leaf litter was similarly found to improve the resiliency of eucalypt roots. In both red soil and litter matrix, the leachate processing time and root growth showed a highly significant, positive correlation.