月桂醇对黄瓜生长和抗霜霉病及其生理指标的影响

摘要

以黄瓜霜霉病为研究对象，用浓度分别为0.00(CK)，0.05，0.10，0.50，1.00，2.00 mmol·L-1的月桂醇处理黄瓜幼苗，探讨其对接种黄瓜霜霉菌后黄瓜植株生长状况、发病情况和相关防御酶活性的影响。结果表明：0.05~1.00 mmol·L-1月桂醇处理，降低了黄瓜霜霉病的发病率和病情指数，其中以0.10 mmol·L-1处理效果最好，对照严重发病时，其发病率仅为44.44%，病情指数为15.87，防治效果达63.53%；低浓度月桂醇对黄瓜植株的株高、茎粗、鲜质量、根系活力及苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)活性均表现为促进作用，0.10 mmol·L-1月桂醇处理的促进作用最大；而低浓度月桂醇降低了脯氨酸含量和相对电导率,0.10 mmol·L-1月桂醇处理的抑制作用最大。说明0.10 mmol·L-1月桂醇处理效果最佳。%The cucumber downy mildew(Pseudoperonospora cubensis) was adopted as the experimental object. Cucumber seedlings were treated with six concentrations of dodecanol, 0.00 (CK), 0.05, 0.10, 0.50, 1.00 and 2.00 mmol·L-1, then tested the incidence of cucumber plants inoculated with Pseudoperonospora cubensis, cucumber seedling growth, physiological and biochemical indicators, in order to determine its effect on cucumber growth. The results of field investigation indicated that dodecanol enhanced the downy mildew disease resistance of cucumber at the concentrations of 0.05-1.00 mmol·L-1, the best effect was observed at 0.10 mmol·L-1,the incidence was only 44.44%, the disease index was 15.87, the disease control effect reached 63.53%. Dodecanol at low concentration promoted the cucumber stem height, stem diameter, fresh matter, root vigor, PAL activity, POD activity and PPO activity,at 0.10 mmol·L-1 it has the bigggest promotion. But it decreased proline content, relative electricity conductivity. Up to 0.1mmol·L-1, dodecanol presented the strongest inhibition .It was concluded that 0.10 mmol·L-1 treatment has the biggest allelopathic promtion.