5种植物对薇甘菊化感作用研究

用水作为溶剂对云南省薇甘菊发生地伴生的常见本地物种异型莎草(Cyperus difformis)、水蓼(Polygonum hydropiper)和外来物种空心莲子草(Alternanthera philoxcroides)、三叶鬼针草(Bidens pilosa L.)以及农粮作物红薯(Ipomoea batatas)地上部分进行提取,后将各提取液配制成一定质量浓度的营养液培养薇甘菊幼苗,12 d后测其对薇甘菊幼苗的生长抑制情况.结果表明,5种供试植物的水提取物均能抑制薇甘菊幼苗的生长,且彼此间存在一定的差异.5种植物化感作用的综合抑制效应总体表现为:空心莲子草＞异型莎草＞三叶鬼针草,水蓼和红薯对薇甘菊幼苗生长的抑制程度相似,但强度明显弱于前3种植物;不同供试植物的水提取物对薇甘菊幼苗新增质量的受抑制程度均大于茎长和根长的受抑制程度.说明入侵地许多与薇甘菊伴生的物种具有抑制薇甘菊幼苗生长的化感作用,其中外来种群的抑制作用总体强于本地种群.

Allelopathy of 5 Associated Species on Mikania micrantha H.B.K

Allelopathy of 5 associated species(Cyperus difformis, Polygonum hydropiper, Alternanthera philoxcroides, Bidens pilosa L.and Ipomoea batatas )on invasive plant Mikania micrantha H.B.K was studied. The bioactivity of aqueous extract from overground part of 5associated species was evaluated on the growth of Mikania micrantha H.B.K. seedling.The results showed that aqueous extract from 5 associated species inhibited growth of Mikania micrantha H.B.K. seedling and the inhibiting order was Alternanthera philoxcroides＞Cyperus difformis＞Bidens pilosa L., the Polygonum hydropiper and Ipomoea batatas had similar the inhibition rate but were obviously weak to others.The weight were inhibited more than stem and root. These results showed associated species had allelopathic to Mikania micrantha H.B.K. seedling and effects of alien populations were more than that of local species.