吉林省玉米根腐镰孢菌种类鉴定和防治药剂筛选

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

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。

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.