嘉峪关市新城镇洋葱干腐病病原鉴定及致病性测定

对嘉峪关市新城镇中沟2队、中沟6队、新城4队、新城8队及长城2队的洋葱干腐病植株病原进行了分离,共获得89株镰刀菌单孢株系.依据Booth和Burgess分类系统,根据其形态特征鉴定为尖孢镰刀菌(Fusariumoxysporum)、茄病镰刀菌(Fusariumsolani)和串珠镰刀菌(Fusarium moniliforme),其中尖孢镰刀菌所占比例最大,为69.66%,茄病镰刀菌和串珠镰刀菌所占比例分别为21.99%和8.35%.室内平皿致病性测定结果表明,尖孢镰刀菌、茄病镰刀菌、串珠镰刀菌都有致病性,病情指数依次为60.2、20.4和20.1,其中尖孢镰刀菌的致病能力最强,是引起洋葱干腐病的主要病原菌,而茄病镰刀菌和串珠镰刀菌作为洋葱干腐病病原在国内属首次报道.

Pathogens identification and pathogenic testing of onion dry rot disease in Xincheng Town of Jiayuguan City

Eighty nine onion dry rot disease strains were obtained from Xinchen Town,Jiayuguan City,Gansu Province.Based on the morphological characters and the taxonomy systems of Booth C.& Lester.W.Burgess,3 species were found,including Fusarium oxysporum,Fusarium solani and Fusarium moniliforme.Among which F.oxysporum was widely spread and accounted for the highest percentage of 69.66 %,while F.solani and F.moniliforme took relatively lower percentage of 21.99 % and 8.35 %,respectively.Pathogenic testing results showed that all the 3 kinds of Fusarium strains had pathogenicity and the disease indexes were 60.2,20.4 and 20.1,respectively.F.oxysporum caused the strongest pathogenicity and acted as the main pathogen to onion dry rot disease.It was first report in China that the F.solani and F.moniliforme could cause onion dry rot disease.