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期 刊 ：植物保护学报 2006年

关键词：白三叶草；化感作用；杂草；生理生化机制；

Keywords:White clover, allelopathy, weeds, physiological and biochemical mechanism,

摘 要 ：为进一步明确白三叶草对杂草的化感作用,研究了不同浓度的白三叶草地上部分水浸液和根部水浸液对苘麻和稗草种子发芽率和种子萌发过程中生理生化机制的影响。结果表明,白三叶草地上部分水浸液和根部水浸液显著抑制苘麻和稗草种子的发芽率,降低了杂草种子萌发过程中超氧化物歧化酶、过氧化氢酶的活性,抑制了杂草种子萌发过程中的呼吸速率、根系活力,明显提高了杂草种子过氧化物酶活性和丙二醛的含量。用浓度0.1 g/mL的地上部分水浸液处理稗草种子后,最终发芽率降低56%,稗草种子萌发过程中超氧化物歧化酶、过氧化氢酶的活性分别降低24.78%、48.69%,呼吸速率和根系活力分别降低40.63%、36.28%,过氧化物酶活性和丙二醛的含量分别提高32.30%、87.40%。随着水浸液浓度的提高,化感作用增强,地上部分水浸液对杂草的化感作用大于根部水浸液,对稗草的抑制作用大于苘麻的化感作用。

Abstract:In order to ascertain the allelopathy activity of Trifolium repens on weeds, the allelopathic effect of aqueous extract from the aerial part and root of T.repens under different concentrations on the germination rate, physiological and biochemical mechanism of germinating seeds of Abutilon theophrasti Medic. and Echinochloa crusgalli L. were studied. Both of the aqueous extract from aerial part and root of T.repens inhibited the germination rate of weed seeds, root activity and respiratory rate, and the activities of superoxide dismutase peroxidase and catalase of germinating seeds; enhanced the activity of peroxidase and the content of malondialdehyde. The germination rate reduced by 56% when barnyardgrass seed was treated with 0.1 g/mL aqueous extract from the aerial part, the activities of superoxide dismutase peroxidase and catalase of germinating seeds were reduced by 24.78%, 48.69%, the root activity and respiratory rate were reduced by 40.63%, 36.28%, the activity of peroxidase and the content of malondialdehyde were enhanced by 32.30%, 87.40% at the same time. The allelopathic effect became stronger along with the increase of concentration of aqueous extract, the allelopathy of aqueous extract from the aerial part of T.repens on two weeds is higher than that of the aqueous extract from the root, the allelopathy on E.crusgalli is higher than that on A.theophrasti.

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