岩生植物金发草对作物的化感效应

采用生物测定法研究金发草根、茎、叶水浸提液对水稻、小麦、油菜和莴苣等4种受体植物的化感作用。结果表明,金发草根、茎、叶水浸提液对4种受体植物种子萌发和幼苗生长均具化感作用,且随着水浸提液浓度的增高而增强。除水稻外,小麦、油菜、莴苣的发芽速率均受金发草水浸提液的显著抑制,但对最终发芽率影响不显著,说明金发草对植物种子萌发的化感作用主要是延迟种子发芽时间;金发草对作物幼苗生长的化感作用总体上表现为促进地上部分生长而抑制地下部分的生长。受体植物不同发育期对金发草化感作用的敏感程度不同,幼苗期高于萌发期;金发草叶的化感作用最强,其综合效应分别为根与茎的2.14倍和2.56倍。

Allelopathic effects of rock plant Pogonatherum paniceum on crops

In the present study,the allelopathic effects of root,stem and leaf aqueous extracts of Pogonatherum paniceum on seed germination and seedling growth in Oryza sativa,Triticum aestivum,Brassica campestris and Lactuca sactiva by the methods of bioassay were tested.The results showed that all aqueous extracts have allelopathy on four receptor plants,increasing with the increase of concentration.The aqueous extracts of P.paniceum inhibited seed germination and root length,and promoted seedling height in principle.The germination speeds of T.aestivum,B.campestris and L.sactiva were significantly inhibited except O.sativa.No significant effects of aqueous extracts on final germination of receptor plants showed that the allelopathy of P.paniceum delayed seed germination of receptor plants.Sensitivity to aqueous extracts was different between development periods in this study,and seedling period was sensitive than germination period.The leaf allelopathy was 2.14 times of root and 2.57 times of stem of P.paniceum,respectively.