大狼毒对紫花苜蓿种子萌发及幼苗生长的化感效应研究

为探究大狼毒(Euphorbia jolkinii)是否会对其它物种产生化感作用，促进大狼毒蔓延区退化草地的恢复治理，本研究以紫花苜蓿(Medicago sativa)为受体材料，采用培养皿滤纸法和穴盘培养法，开展大狼毒对紫花苜蓿种子萌发及幼苗生长的化感效应研究，结果表明：大狼毒对紫花苜蓿种子萌发率和萌发进程体现为“化感抑制作用”,且抑制作用随浸提液浓度的增加而增强。大狼毒茎叶、根粉碎物在腐解过程中，会导致紫花苜蓿根系活力和可溶性糖含量降低，丙二醛(Malondialdehyde, MDA)含量升高，进而显著抑制紫花苜蓿幼苗的生长(P<0.05),且抑制作用随用量的增加而增强。大狼毒根部土壤对紫花苜蓿幼苗生长无显著影响。大狼毒根部土壤、根、茎叶对紫花苜蓿萌发生长的综合化感效应强弱顺序为：根>茎叶>根部土壤。

Allelopathic Effects of Euphorbia jolkinii on Seed Germination and Seedling Growth of Alfalfa

To explore whether Euphorbia jolkinii has an allelopathic effect on other species and promote the restoration and management of degraded grassland in the spreading area of E.jolkinii,the allelopathic effect of E.jolkinii on seed germination and seedling growth of alfalfa were studied by dish filter paper method and hole disc culture method.The results showed that the allelopathic effects of E.jolkinii on alfalfa seed germination rate and germination process were“inhibition”,and the inhibition intensity increased with the increase of extract concentration.During the decomposition process of stem,leaf,and root debris of E.jolkinii,the root activity and soluble sugar content of alfalfa decreased,and the MDA content increased,which significantly inhibited the growth of alfalfa seedlings(P<0.05),and the inhibition intensity increased with the increase of dosage.The root-soil treatment of E.jolkinii had no effect on the growth of alfalfa seedlings.The comprehensive allelopathic effects of root-soil,root,stem,and leaf of E.jolkinii on the germination and growth of alfalfa were in the order of root>stem and leaf>root soil.