银胶菊根际土壤化感作用的初步研究

研究银胶菊根际土壤浸提液对蔬菜种子和幼苗的化感作用。采用水浸提法制备不同浓度的银胶菊根际土壤浸提液，用生物测定法测定其对上海青、甜菜、苋菜种子萌发和幼苗生长的化感效应。银胶菊不同浓度土壤浸提液对3种植物种子萌发总体具有抑制作用，但对甜菜的GI表现为促进作用，同一浓度的土壤浸提液对3种植物种子发芽率的抑制作用大小顺序为苋菜>上海青>甜菜。与对照相比，幼苗根长和苗高发生明显变化；游离脯氨酸含量均高于对照，且随浸提液处理浓度的增加呈现升高趋势，而可溶性糖含量变化的趋势不一致。银胶菊根际土壤浸提液具有一定的的化感效应，且对不同植物及不同生长特性的化感效应具有选择性。

Allelopathic Effects of Water Extract from Rhizosphere Soil of Parthenium Hysterophorus

The aim was to study the allelopathic effect of aqueous extracts from rhizosphere soil of Parthenium hysterophorus on seed and seedling of vegetables. Aqueous extracts with different concentrations of rhizosphere soil of Parthenium hysterophorus were prepared to study their allelopathic effects on seed germination and seedling growth of three plant acceptors （Brassica chinensis, Beta vulgaris and Amaranthus tricolor）. The results showed that the water extracts with different concentration had inhibitory effects on the rate of germination of three plants in general, but it increased the seed germination index of Beta vulgaris. The order of restraining effect from strong to weak was Amaranthus tricolor, Brassica chinensis, Beta vulgaris. Compared with contract, the root length and the seedling height changed significantly; the free proline contents were all higher than those in control and the promotion became stronger as the concentration of aqueous extract increased; while the contents of soluble sugar changed differently. The aqueous extracts from rhizosphere soil of Parthenium hysterophorus had certain allelopathic effects with different selectivity on different plants and different growth characters.