甜瓜抗白粉病的苗期鉴定  

Identification method of resistance to powdery mildew in melon at seedling stage

作　　者：康保珊[1] 郝小苑 吴会杰[1] 彭斌[1] 刘莉铭[1] 古勤生[1] KANG Baoshan;HAO Xiaoyuan;WU Huijie;PENG Bin;LIU Liming;GU Qinsheng(Zhengzhou Fruit Research Institute,Chinese Academy of Agricultural Sciences,Zhengzhou 450009,Henan,China)

机构地区：[1]中国农业科学院郑州果树研究所,郑州450009

出　　处：《中国瓜菜》2022年第11期22-26,共5页China Cucurbits And Vegetables

基　　金：国家自然科学基金重点项目(U21A20229);财政部和农业农村部:国家现代农业产业技术体系(CARS-25);中国农业科学院科技创新工程(CAAS-ASTIP-2022-ZFRI-09);中央级公益性科研院所基本科研业务费专项(1610192022105)。

摘　　要：为筛选快速高效的甜瓜白粉病苗期人工接种鉴定方法,选择6个甜瓜品种作为试材,围绕接种苗龄、接种液浓度、调查时间点3个重要因素设置试验处理,筛选周期短且结果稳定的试验组合,确定甜瓜苗期室内最佳的鉴定方法。结果显示,部分甜瓜品种子叶期接种的病情指数与真叶期相比差异显著,表明子叶期不适合甜瓜白粉病接种;2叶1心期和4叶1心期接种的病情指数之间差异不显著,因此为缩短鉴定周期,2叶1心期为最佳接种时期;通过设置不同接种浓度发现,当孢子浓度为104个·mL^(-1)时,感病品种接种后12 d的病情指数无法达到感病级别,而当孢子浓度为107个·mL^(-1)时,供试品种的病情指数偏高,甜瓜白粉病菌适宜的接种浓度为105~106个孢子·mL^(-1)。综上所述,甜瓜白粉病抗性鉴定的最佳接种条件为:植株在2叶1心期接种浓度为105个·mL^(-1)的孢子悬浮液并于接种后12 d进行调查或接种浓度为106个·mL^(-1)的孢子悬浮液并于接种后8~12 d调查,其结果可充分展示不同品种间的抗性差异。In order to determine the rapid and efficient inoculation methods for powdery mildew on melon seedlings,in this study,we used six varieties of melon(Cucumis melo L.)to analyze the effect of spore suspension concentration,seedling age,and investigation time on disease indexes(DIs)of melon powdery mildew(Podosphaera xanthii).The method with time-saving and stable results was determined to be the optimal identification method for melon at seedling stage.The results showed that the DIs of some melon varieties inoculated at the cotyledon stage were significantly different compared to that at the true leaf stage,indicating the cotyledon stage was not optimal for inoculation.Compared DIs at two true leaves stage and four true leaves stage,no significant difference was displayed.Therefore,two true leaves stage was considered as the best inoculation period to shorten the identification time.In the test of spore concentration,it was found the DIs of the susceptible varieties at 12 day post-inoculation(dpi)could not reach the susceptible level when inoculation using 104 spores·mL^(-1).While the spore concentration was 107 spores·mL^(-1),the DIs of the tested varieties were higher than other concentrations,maybe leading to a big deviation from the field resistance.The results indicated that the appropriate inoculation concentrations for powdery mildew of melon range from 105 to 106 spores·ml^(-1).Taken together,the optimal inoculation conditions for the identification of melon powdery mildew resistance were determined as follows:at two true leaves stage the seedlings were inoculated with 105 spores·mL^(-1)and investigated at 12 day,or with 106 spores·ml^(-1)and investigated at 8-12 day.Under the conditions,the results can fully screen out the resistance among different varieties.

关 键 词：甜瓜 白粉病 苗期 抗性 

分 类 号：S652[农业科学—果树学]