The Study On Allelopathy And Its Mechanism Of The Parsley Dried Roots Extract On Fusarium Oxysporiumf. Sp. Cucumeris

It was conduced that the allelopathic of the extract of the dried root parsley on Fusarium oxysporum.sp.cucumeris by growth rate method, and gives the primary research on the allelopathic senses and allelopathic mechanism through the determination of Fusarium oxysporum.sp.cucumeris bacterium body protect enzymes and MDA, hydrogen peroxide, soluble protein content. Experimental results show that the extract of dried root parsley solution concentration (water in leaching solution concentration for 100% - 50% ethanol and acetone extraction liquid density is 100%-40%)to Fusarium oxysporum.sp.cucumeris has inhibitory effect, low concentration has simulative effect. As the extension of time and concentration, the allelopathy of the extract of dried root parsley solution to Fusarium oxysporum.sp.cucumeris reduces. In which it includes ethanol extraction inhibitory effect for optimal is 77.02%, water and acetone extraction inhibition rate are 20.74% and 19.32% respectively, and the best allelopathic effects among them is the ethanol extraction. The later growth situation on the three extract after the role of Fusarium oxysporum.sp.cucumeris of parsley dried root: colony contrast blank > colony diameter > with 100% colonies diameter. In 24h-120h, hyphae after ethanol extraction still has the allelopathy effect; in 24h-96h, hyphae after acetone extraction has the allelopathy; in 24h-72h, hyphae after water extraction has the allelopathic effects, the growth of hyphae of allelopathy after the three extract solution have been suppressing continuously, but as time increases, their inhibitory effects are descending. Fusarium oxysporum.sp.cucumeris mycelium protect enzymes inside overall trends is reduced, the three kinds of extract after treatment of the protection of the enzyme activity reduced, SOD reduced 16% - 40%, POD dropped 31%-34%, and CAT reduced 37%-38%.Fusarium oxysporum.sp.cucumeris mycelium of SOD and POD and CAT's activity are reduced, damaging the plasma membrane's defense mechanism and losing the protection function, thus inhibiting the hyphae growth. Compared with controls, the Fusarium oxysporum.sp.cucumeris mycelium of MDA has increased 10%-16%; hydrogen peroxide content has increased 20%-30%; soluble protein content has increased 21%-34%.