黄淮海地区夏玉米灰斑病病原菌鉴定及主栽品种抗性分析

 为明确黄淮海夏玉米区玉米灰斑病的病原菌种类,于2017年从河北、河南、山东、安徽、天津五省市疑似发生玉米灰斑病的76个市县采集样本,采用组织分离法和显微单孢分离法获得病原菌,通过形态与分子生物学手段进行病原菌种类鉴定,并对黄淮海地区、陕西、辽宁、黑龙江的37个菌株进行ISSR聚类分析。结果表明,引起黄淮海地区玉米灰斑病的病原菌为玉蜀黍尾孢(Cercospora zeae-maydis),玉蜀黍尾孢的变异具有地理种群特征。同时对黄淮海夏玉米区主栽品种进行人工接种鉴定,结果显示6个主栽品种中郑单958、登海605、先玉335、浚单20等4个品种对玉米灰斑病抗性较差,玉米灰斑病在本区域具有大面积发生和流行的风险。本研究为黄淮海夏玉米区灰斑病的综合防控提供支撑和理论依据。

Identification of causal agent of gray leaf spot and resistance of important hybrids in Huanghuaihai summer maize region

In order to clarify the pathogen of maize gray leaf spot disease in the Huanghuaihai summer maize region, samples were gathered from 76 counties suspected to have this disease in Hebei, Henan, Shandong, Anhui and Tianjin in 2017. Isolates were obtained by tissue separation and single spore isolation and were identified by morphological and molecular methods. ISSR clustering analysis performed on 37 isolates from Huanghuaihai region, Shaanxi, Liaoning and Heilongjiang. The results showed that Cercospora zeae-maydis was the pathogen of maize gray leaf spot disease in Huanghuaihai region, and the variation of C. zeae-maydis had geographical population characteristics. Moreover, artificial inoculation identification of maize main cultivars in Huanghuaihai summer maize region showed that four of the six main cultivars (Zhengdan 958, Denghai 605, Xianyu 335, and Xundan 20) exhibited low resistances to gray leaf spot, so this disease had a large risk of occurrence and prevalence in this region. This study provided a theoretical basis for comprehensive prevention and control of gray leaf spot disease in Huanghuaihai summer maize region.