玉米灰斑病菌致病性分化的寄主鉴定方法

玉米灰斑病现已严重威胁中国北方玉米生产的可持续发展。本研究采用苗期鉴定、成株期鉴定、温室鉴定和田间鉴定等方法，利用玉米自交系和品种对玉米灰斑病菌致病性分化鉴定方法进行了研究。结果表明：玉米苗期和成株期均可用于玉米灰斑病的抗性鉴定，两者鉴定结果有一定的相似性，但利用成株期进行鉴定比较好，因为接种比较容易；利用自交系或品种均可进行抗性鉴定，从效果上看，利用自交系较好，因为利用成株期自交系鉴定法，不同自交系一菌株组合间病级差异较明显，变异系数为47．32％，能有效地区分不同菌株间致病性分化的程度，但是由于成株期品种鉴定法与成株期白交系鉴定法比较。变异系数差异很小，所以成株期品种鉴定法可以作为抗性鉴定的辅助方法。

Identification Method of Pathogenicity Differentiation of Gray Leaf Spot Pathogen

The gray leaf spot(GLS) disease threatens seriously the sustainable development of maize production in recent years in North China.The identification methods of pathogenicity differentiation of GLS pathogen were studied.The seedling and,adult identifications,greenhouse and field identifications were used to examine the pathogenicity differentiation of GLS pathogen in maize inbreds and hybrids.The results showed that the resistance identification could be done at both seedling and adult plant stages.The result of the adult plant identification was better because of easier inoculation.The resistance identification using maize inbreds was superior to that of maize bybrids,because the differences of different inbred-isolate groups could be evidently examined using inbred identification of adult plants.Coefficient of variability was 47.32%.Therefore,this method can effectively examine the degree of pathogenicity differentiation of different isolates.Because of the lower coefficient of variability of hybrids identification than inbred identification in adult approach,hybrids identification in adult can be an auxiliary method of resistance identification.