狼毒水浸液对山韭种子发芽及幼苗生长的化感作用

The Allelopathic Effect of Aqueous Extracts of Stellera chamaejasme on Seed Germination and Seedling Growth of Allium senescens

本文以狼毒(Stellera chamaejasme)为供体植物,探讨其根、茎叶水浸液对草原伴生种山韭(Allium senescens)种子发芽与幼苗生长的影响,为狼毒对牧草化感作用的研究提供新材料,并为揭示其对山韭的化感作用机制提供理论参考。结果表明:狼毒根、茎叶水浸液对山韭种子发芽具有抑制作用,且随浓度的增加逐渐增强,发芽率分别降低了43.94%和87.13%;狼毒根、茎叶水浸液对山韭种子胚根、胚芽及幼苗的生长具有“低促高抑”的化感作用,即低浓度(0.5,5和10mg·mL^(-1))促进,高浓度(20和50mg·mL^(-1))抑制;化感效应指数表明,狼毒茎叶水浸液对山韭种子发芽的化感抑制作用强于根水浸液;对山韭种子胚根、胚芽及幼苗生长的化感作用表明,低浓度根水浸液的化感促进作用强于茎叶水浸液,而高浓度茎叶水浸液的化感抑制作用强于根水浸液。研究说明了狼毒对山韭不同的生长阶段均存在一定的化感作用,且与其部位的化感效应存在规律性变化。

In this paper,Stellera chamajasme was taken as the donor plant to study the allelopathic effects of aqueous extracts from root,stem,and leaf on seed germination and seedling growth of the accompanying species,Allium senescens,in grassland.This study provided new materials for revealing allelopathy of herbage by S.chamaejasme and provided a theoretical reference for exploring the allelopathic mechanism of S.chamaejasme to A.senescens.The results showed that:(1)The aqueous extracts of the root,stem,and leaf of S.chamajasme had inhibitory effect on seed germination of A.senescens,and the germination rate decreased by 43.94%and 87.13%with the increase of the concentration.(2)The aqueous extracts of the root,stem,and leaf of S.chamajasme had allelopathic effect on the growth of the radicle,plumule,and seedling of A.senescens,i.e.low concentration(0.5,5,and 10mg·mL^(-1))aqueous extracts promoted them,while high concentration(20and 50mg·mL^(-1))aqueous extracts inhibited them.(3)The allelopathy intensity of different parts of S.chamajasme showed that the aqueous extracts from stem and leaf had stronger inhibition on seed germination than that from the root.In the same way,the allelopathic effects of different aqueous extracts on the growth of radicle,plumule,and seedling of A.senescens showed that the promotion effect of low concentration of aqueous extracts from the root was stronger than that from stem and leaf,while the inhibition effect of high concentration of aqueous extracts from stem and leaf was stronger than that from the root.Therefore,we concluded that the allelopathic effects of S.chamaejasme on different growth stages of A.senescens were observed,and which of its different parts varied regularly.