title: Occurrence of Leaf Blight on Cosmos Caused by Alternaria cosmosa in Korea.
abstract: In 2011, a leaf blight disease was observed on cosmos (Cosmos bipinnatus) leaves in Nonsan, Korea. The causal pathogen was isolated and identified based on morphological and molecular approaches. Morphological characteristics of the pathogen matched well with the Alternaria cosmosa and also easily distinguishable from Alternaria zinniae reported from cosmos seeds by producing branched beak. Phylogenetically, the pathogen could not be distinguished from A. passiflorae based on the sequence analysis of a combined data set of Alt a1 and gpd genes. However, A. passiflorae was distinguished from the present species by having conidiophores with 4 to 5 conidiogenous loci. The results indicate that the present Alternaria species is A. cosmosa. Pathogenicity tests revealed that the isolate was pathogenic to the leaves of Cosmos bipinnatus. This is the first report of Alternaria blight disease caused by A. cosmosa on cosmos in Korea.
authors.affiliation: Department of Plant Protection, College of Agriculture, Yangtze University, Jingzhou 434025, China.
authors.forename: Jian Xin
authors.initials: JX
authors.lastname: Deng
authors.affiliation: Department of Applied Biology, College of Agriculture and Life Sciences, Chungnam National University, Daejeon 305-764, Korea.
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Division of Applied Bioscience & Biotechnology, College of Agriculture & Life Sciences, Chonnam National University, Gwangju 500-757, Korea.
authors.forename: Narayan Chandra
authors.initials: NC
authors.lastname: Paul
authors.affiliation: Ginseng Resources Institute, Korea Ginseng Corp., Daejeon 305-805, Korea.
authors.forename: Hye Sun
authors.initials: HS
authors.lastname: Cho
authors.affiliation: Division of Applied Bioscience & Biotechnology, College of Agriculture & Life Sciences, Chonnam National University, Gwangju 500-757, Korea.
authors.forename: Hyang Burm
authors.initials: HB
authors.lastname: Lee
authors.affiliation: Department of Applied Biology, College of Agriculture and Life Sciences, Chungnam National University, Daejeon 305-764, Korea.
authors.forename: Seung Hun
authors.initials: SH
authors.lastname: Yu
keywords: asteraceae; morphology; pathogenicity; phylogenetic analysis