吉林省玉米根腐镰孢菌种类鉴定和防治药剂筛选

通过形态学和分子生物学方法对2016年采自吉林省36个村镇的玉米根腐病样品进行镰孢菌分离和鉴定,并通过田间试验筛选有效药剂。结果发现,共分离获得84株镰孢菌,主要包括尖孢镰孢、禾谷镰孢、拟轮枝镰孢、层出镰孢、三线镰孢等11种镰孢菌,其中尖孢镰孢平均分离频率最高,为45.2%;其次是禾谷镰孢,平均分离频率为20.2%。从分布区域看,尖孢镰孢是白城、吉林、辽源和通化地区玉米根腐病的主要致病菌,分离频率分别为75%、54.5%、85.7%和45.5%;禾谷镰孢是松原和四平地区玉米根腐病的主要致病菌,分离频率分别为41.7%和41.7%。田间试验表明,5种药剂的防治效果为16.35%～81.26%,药种比为10 g/kg的10%咯菌腈悬浮种衣剂对玉米根腐病防治效果最好,防效达81.26%。吉林省玉米根腐病的主要病原菌为尖孢镰孢,药种比为10 g/kg的10%咯菌腈悬浮种衣剂可用于玉米根腐病的田间防治。

Identification of Fusarium Species causing Maize Root Rot in Jilin Province and Screening of Fungicides

To clarify the population structure characteristics of Fusarium species causing maize root rot in 36 counties of Jilin province and effective seed-coating fungicides, the pathogenic fungus of maize root rot was identified with the method of isolation and sequence of rDNA-ITS, CL and efficacy of the used fungicides were evaluated in the field. The results showed 11 species were identified among the 84 isolates of Fusarium, including F. oxysporum, F. graminearum, F. verticillioides, F. proliferatum, Fusarium tricinatum and so on. The isolation frequency of F. oxysporum was the highest, accounted for 45.2%. The next isolation frequency of F. graminearum is 20.2%. Fusarium oxysporum was the dominant species causing maize root rot in Baicheng, Jilin, Liaoyuan and Tonghua with frequencies of 75%, 54.5%, 85.7% and 45.5%, respectively. Fusarium graminearum was the dominant species in Songyuan and Siping city with frequencies of 41.7% and 41.7%, respectively. Field trials showed that the control effect of 5 fungicides on maize root rot was 16.35%-81.26%, and among them, 10 g/kg of 10% fludioxoni FSC had the greatest control effect with control efficacy up to 81.26%. The results indicated that the main pathogen of maize root rot was F. oxysporum in Jilin province, 10 g/kg of 10% Fludioxoni FSC could be used to control maize root rot.