Isolation and Identification of Plantain(Musa paradisiaca Linn.) Fusarium Wilt Disease Pathogen and Pathogenicity Test

Plantain(Musa paradisiaca Linn.)is an edible banana,and the causal agent of plantain wilt disease hasn't been reported until now.In this study,ten isolates(DJ1-10)from the corms of the plantains that showed wilt symptoms were isolated.These isolates were preliminarily identified as Fusarium oxysporm based on their morphological characteristics.Then phylogenetic analysis based on the sequences of rDNA-ITS and intergenic spacer(IGS)regions added proof that the isolate DJ1 was F.oxysporum.The pathogenicity assays showed that DJ1 was able to infect 5 varieties of the genus Musa including Fenjiao(Musa sp.ABB),Hangdijiao(Musa sp.AA),Taijiao(Musa sp.AAA),Tewei(Musa sp.AAA)and Brazilian(Musa sp.AAA),but it was most pathogenic to Fenjiao,then Tewei,Taijiao and Bazilian,and it was less pathogenic to Huangdijiao.These results imply that DJ1 might be an isolate from race 4 of Fusarium oxysporum f.sp.cubense(Foc).