Allelopathy of methanol dissolved ingredient from garlic plant aqueous extracts

chinois. 为了解大蒜化感作用的机理，利用大蒜构建合理的栽培制度，以水浸提大蒜植株，XAD-4树脂吸附后用甲醇洗脱，真空浓缩至干,以蒸馏水溶解获得大蒜植株水浸液醇溶成分，在5种质量浓度梯度下，用蒸馏水为对照，对6种受体蔬菜进行发芽和幼苗生长生物测定，研究大蒜植株水浸液醇溶成分的化感作用。结果表明，0.04 g/mL大蒜植株水浸液醇溶成分对黄瓜、番茄、甜椒、甘蓝、茄子的发芽率、发芽指数及幼苗生长表现出抑制效应，对甜瓜的发芽和生长表现出促进效应。大蒜植株水浸液醇溶成分对番茄表现为低质量浓度促进和高质量浓度抑制的化感效应，0.005 g/mL低质量浓度对番茄苗高和根长分别有极显著和显著的促进作用；但从质量浓度0.01 g/mL开始，对番茄地上部鲜重、根长及根鲜重表现为抑制作用，根系活力高于对照且持续增加；从质量浓度0.02 g/mL开始，对番茄发芽率、发芽指数和苗高表现为抑制作用；从质量浓度0.02 g/mL或0.03 g/mL开始，番茄MDA含量、保护酶SOD和CAT的活性及非保护酶PAL和PPO的活性分别高于对照且持续增加，POD活性急剧降低。以上结果表明,番茄是大蒜植株水浸液醇溶成分的敏感受试作物，高质量浓度的大蒜植株水浸液醇溶成分破坏番茄膜系统，影响番茄植株正常生长。

anglais. In order to know the mechanism of galic allelopathy, and make use of galic to set up rational cropping system, the test used galic plant aqueous extracts adsorbed by XAD-4 resin and dissolved by methanol, then concentrated in vacuum, and dissolved in distilled water by using distilled water for control, to study the allelopathy of methanol dissolved ingredients from garlic plant aqueous extracts on six receiver vegetable crops through bio-assay of seed germination and seedling growth of the receiver crops. The results indicated that at the concentration of 0.04 g/mL 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, the crop length and root length of tomato increased most significantly and significantly, respecitively. However, starting from the concentration of garlic extracts increased to 0.01 g/mL, the top fresh weight, root length and root fresh weight of tomato were inhibited, and the content of MDA and the root vigor increased to the level higher than the control; starting from the concentration of garlic extracts increased to 0.02 g/mL, 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 or 0.03 g/mL, 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 showed gradually increasing trend. Tomato was proved the most sensitive crop among the six receiver crops; height mass of methanol dissolved ingredient from gaarlic plant aqueous extracts would destroy tomato film system under thickness, and therefore influence its normal growth.