The Allelopathy And Inhibitory Effect Of Garlic Plant Aquepus Extracts

Be knowing the galic allelopathy and the mechanism, used galic plant aqueous extracts, methanol dissolved after XAD-4 resin adsorpt, than vacuum concentrated to distilled water dissolved again,used under five concentration and distilled water for control, studied the allelopathy of methanol dissolved ingredients from garlic plant aqueous extracts.The results indicated that at the concentration of 0.04 g·mL-1 garlic extracts showed inhibitory effects on seed germination rate, germination index and seedling growth of cucumber, tomato, sweet pepper, cabbage and eggplant, but promotion effect on melon. Garlic extracts showed double allelopathic concentration effects on tomato,suppression at low concentration and promotion at high concentration.At the low concentration of 0.005 g·mL-1,the crop length and root length of tomato were most signisicantly and signisicantly increased,respecitively.However,starting from the concentration of garlic extracts increased to 0.01 g·mL-1, the top fresh weight, root length and root fresh weight of tomato were inhibited,and the content of MDA and the root vigor were increased to the level higher than the control. starting from the concentration of garlic extracts increased to 0.02 g·mL-1,the germination rate, germination index and top length of tomato were inhibited. starting from the concentration of garlic extracts increased to 0.02 g·mL-1or 0.03 g·mL-1,the activities of protective enzymes SOD and CAT,and the non-protective enzyme PAL and PPO of tomato were also increased to the level higher than the control and appeared the standing increasing trend. So the methanol dissolved ingredients from garlic plant aqueous extracts had allelopathy to the six receiver crops ,and tomato was the most sensitive crop, tomato membrane system was destroyed under the high concentration, influenced the normal growth of test crop.Through hydroponics test,the allelopathy of garlic on tomato was studied through investigating the effects of garlic plant aqueous extracts on seedling growth.The results indicated that the activities of protective enzymes SOD,CAT,POD and the root vigor decreased firstly and increased and then rapid decreased again at the concentration of 0.02 g·mL-1,the non-protective enzyme PAL,PPO activity and the MDA content were higher than control and kept increasing at the concentration of 0.02 g·mL-1. Under the high concentration, the normal growth of tomato was influenced.The suppression circle resulted from different concentration of garlic straw aqueous extracts to Fusarium oxysporum (Schl.)f.sp. cucumerinum Owen, Fusarium oxysporum (Schl.) f. sp. niveum (E. F. Smith) Snyderet Hansen, Phytophthora capsici Leonian was measured.Garlic straw aqueous extracts had inhibitory activity,and the most effective concentration was 0.10 g·mL-1. All the three organic solvent extracts of garlic straw aqueous extracts showed highest inhibitive effect on the pathogens at the concentration of 0.10 g·mL-1.Among them,the ethyl acetate extracts showed the highest inhibitive effect on the pathogens,which reached 100%.By means of GC-MS analysis, the major allelochemicals in garlic straw aqueous extracts were preliminarily determined to be the ester like compounds such as dimethyl 2-methoxyhexane-1,6-dioate and dibutyl phthalate, the organic acid like compounds such as 4-hydroxy-3-methoxy benzoic acid and 4-hydroxy-benzoic acid, and the phenol like compounds such as mequinol.The pathogen inhibitive ingredients in garlic straw aqueous extracts were preliminarily determinated to be phenol like substances.