苗期喷施钾离子对小麦条锈病的影响

Effects of Spraying Potassium Ion on Wheat Stripe Rust in Seedling Stage

[目的]为钾离子在作物抗病中的应用提供参考。[方法]以小麦品种铭贤169为材料,对其1叶1心期的幼苗接种条锈病菌,分别在接菌前24 h、接菌后24 h和接菌后3、7 d对其喷洒1.75、3.50、5.25、7.00 mmol/L氯化钾,接菌12 d后调查发病情况。[结果]接菌前24 h喷氯化钾的处理小麦幼苗的病情指数极显著高于对照（P〈0.01）;接菌后24 h,3.50、5.25、7.00 mmol/L氯化钾处理的小麦幼苗病情指数比对照低18.73%-25.25%,对条锈病的防效为30.30%-40.69%;接菌后3 d,1.75、3.50 mmol/L氯化钾处理的小麦幼苗病情指数极显著低于对照（P〈0.01）,对条锈病的防效为17.14%-18.57%;接菌后7 d,1.75、3.50、5.25 mmol/L氯化钾处理的小麦幼苗病情指数显著低于对照（P〈0.05）,对条锈病的防效为20.25%-39.48%。[结论]钾离子抑制小麦条锈病的最佳浓度为1.75-5.25mmol/L。

[ Objective ] The aim was to provide the reference for application of potassium ion in crop disease-resistant. [ Method ] With wheat variety Mingxian 169 as the material, its seedling was inoculated stripe rust pathogen in a-leaf-a-heart stage, and then the seedling were treated with potassium chloride （ 1.75, 3.50, 5.25, 7.00 mmol/L ） at 24 h before pathogen inoculation, 24 h after pathogen inoculation, 3, 7 d after pathogen inoculation resp. and then the prevalence situation were investigated after 12 d of pathogen inoculation. [ Result] The disease index of wheat seedling in the treatment of spraying potassium chloride at 24 h before pathogen inoculation was very significantly higher than that of CK（P 〈 0.0l ）. The disease indices of wheat seedling in the treatments of spraying potassium chloride （3.50, 5.25, 7.00 mmol/L） at 24 h after pathogen inoculation were 18.73% -25.25% lower than that of CK, and the control efficacy on stripe rust was 30.30% -40.69%. The disease indexes of wheat seedling in the treatments of spraying potassium chloride （ 1.75, 3.50 mmol/L） at 3 d after pathogen inoculation were very significantly lower than that of CK（P 〈0.01 ）, and the control efficacy on stripe rust was 17.14% - 18.57%. The disease indices of wheat seedling in the treatments of spraying potassium chloride （ 1.75, 3.50, 5.25 mmol/L） at 7 d after pathogen inoculation were very significantly lower than that of CK（ P 〈 0.05 ）, and the control efficacy on stripe rust was 20.25% - 39.48%. [ Conclusion] The best concn. of potassium ion on inhibiting wheat stripe rust was 1.75 - 5.25 mmol/L.