【摘要】 枝顶孢霉（Acremonium sp.）BH0531已被证实是一株对根结线虫具有较好防治效果的海洋真菌。为探究其对根结线虫和黄瓜的作用机制,以根结线虫侵染后的黄瓜为材料,在土壤中分别加入质量浓度为5、10、20、40 mg·m L^-1的BH0531发酵液40 m L,用等量清水作对照,测定了丙二醛、脯氨酸含量以及保护酶SOD、POD、CAT、PAL、PPO的比活力。结果表明,接种根结线虫30 d后,黄瓜叶片丙二醛和脯氨酸含量增加,发酵滤液能够显著降低其含量,能够有效缓解根结线虫对黄瓜植株造成的危害。SOD比活力显著提高,能够抵御活性氧带来的伤害;防御酶活力随时间动态变化,先升高后降低,POD、CAT、PAL和PPO比活力与未受根结线虫感染组对比均降低,但施用发酵液时,酶活力均显著提高,能够有效增强植株的抗性。更多还原

【Abstract】 Acremonium sp. BH0531, a marine fungus, has been proved with definite control efficiency on root-knot nematode. To explore the mechanisms in nematode control and growth improvement of cucumbers, pot experiments were conducted indoors to assess the effect of metabolites from BH0531 on physiological indexes and defense enzymes of cucumbers infected by root-knot nematode. Each pot was handled with 40 m L fermentation broth of BH0531 in different concentrations:5, 10, 20, 40 mg·m L^-1, and the control was treated with water instead. Then the amounts of malondialdehyde（MDA） and proline were measured, so were the specific activities of SOD, POD, CAT, PAL and PPO. The results showed that nematode infection increased MDA and proline contents and caused damage in cucumbers, whereas the metabolites effectively reduced the amount of MDA and proline and nearly alleviated the damage. On the other hand, the significant improvement in specific activity of SOD offset the damage of active-oxygen. In short, compared to the control, root-knot nematode infection leads to remarkable decrease in specific activities of POD, CAT, PAL and PPO in cucumbers, but the metabolites of BH0531 can enhance both the specific activities of these defense enzymes and the resistant level of the plants.更多还原