外源MeJA对大白菜根肿病的诱导作用及机制初探  

Preliminary Study on the Mechanism and Induction Effects of Exogenous MeJA on Chinese Cabbage Under the Stress of Clubroot

作　　者：王雅 肖晨 董军[1] 李慧楠 赵利民[1] WANG Ya;XIAO Chen;DONG Jun;LI Huinan;ZHAO Limin(College of Horticulture,Northwest A&F University,Yangling,Shaanxi 712100)

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《北方园艺》2022年第3期1-8,共8页Northern Horticulture

基　　金：财政部和农业农村部:国家现代农业产业技术体系资助项目(CARS-23-G22);陕西省重点研发计划资助项目(2021ZDLNY03-10)。

摘　　要：以大白菜品种"金冠"为试材,采用在根肿病菌胁迫下大白菜根部灌施不同浓度(50~250μmol·L^(-1))茉莉酸甲酯(MeJA)的处理方法,研究MeJA对幼苗生长状况、防御酶、渗透调节物质及相关防御基因表达的影响,以期为外源MeJA防治大白菜根肿病提供参考依据。结果表明:外源MeJA浓度为100μmol·L^(-1)及以上可显著降低根肿病病情指数且根肿病的病情指数与浓度呈负相关;当MeJA浓度为100μmol·L^(-1)时,显著降低了丙二醛(MDA)含量与渗透调节物质。当MeJA浓度大于150μmol·L^(-1)时,抑制白菜幼苗的生长。外源MeJA提高了白菜叶片中叶绿素含量和抗氧化酶活性,诱导PR-1、PR-3病程相关蛋白基因上调表达,从而提高大白菜幼苗对根肿病的抗性。综上所述,在根部灌施100μmol·L^(-1)MeJA时,大白菜幼苗对根肿病的综合抗性效果最佳。Taking Chinese cabbage ‘Jinguan’ as the test material, the different concentrations(50-250 μmol·L^(-1)) of MeJA were applied to the roots of Chinese cabbage under clubroot stress, the effects of MeJA on seedlings growth, defense enzymes, osmoregulation substances and related defense gene expression were studied, in order to provide reference basis for the prevention and treatment of Chinese cabbage clubroot by exogenous MeJA.The results showed that exogenous MeJA could significantly reduce the disease index which was negatively correlated with MeJA concentration, and also significantly decrease MDA and osmoregulation substances contents, especially at the concentration of 100 μmol·L^(-1).While, the growth of cabbage seedlings was inhibited when applying more than 150 μmol·L^(-1)MeJA.Additionally, exogenous MeJA application increased chlorophyll content and antioxidant enzyme activity in Chinese cabbage leaves, as well as up-regulated disease-related protein genes PR-1 and PR-3,so that the resistance of Chinese cabbage seedlings to clubroot was improved.Through comprehensive analysis, application of 100 μmol·L^(-1)MeJA could effectively promote the resistance of Chinese cabbage seedlings to clubroot most.

关 键 词：茉莉酸甲酯 大白菜 根肿病 诱导抗性 

分 类 号：S436.34[农业科学—农业昆虫与害虫防治]