title: Morphological and molecular characterization, sexual reproduction, and pathogenicity of Setosphaeria rostrata isolates from rice leaf spot.
abstract: Setosphaeria rostrata, a common plant pathogen causing leaf spot disease, affects a wide range of plant species, mainly grasses. Fungi were isolated from brown spots on rice leaves throughout Peninsular Malaysia, and 45 isolates were identified as Setosphaeria rostrata The isolates were then characterized using morphological and molecular approaches. The mating type was determined using PCR amplification of the mating type alleles, and isolates of opposite mating types were crossed to examine sexual reproduction. Based on nuclear ribosomal DNA ITS1-5.8S-ITS2 region (ITS) and beta-tubulin (BT2) sequences, two phylogenetic trees were constructed using the maximum likelihood method; S. rostrata was clustered in one well-supported clade. Pathogenicity tests showed that S. rostrata isolates are pathogenic, suggesting that it is the cause of the symptoms. Mating-type analyses indicated that three isolates carried the MAT1-1 allele, and the other 42 isolates carried MAT1-2 After isolates with opposite mating types were crossed on Sach's medium and incubated for 3 wk, six crosses produced pseudothecia that contained eight mature ascospores, and 12 other crosses produced numerous pseudothecia with no ascospores. To our knowledge, this is the first report on S. rostrata isolated from leaf spots on rice.
authors.affiliation: Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Nor Azizah
authors.initials: NA
authors.lastname: Kusai
authors.affiliation: Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Madihah Mior Zakuan
authors.initials: MM
authors.lastname: Azmi
authors.affiliation: Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia ainizzati@upm.edu.my.
authors.forename: Nur Ain Izzati Mohd
authors.initials: NA
authors.lastname: Zainudin
authors.affiliation: Department of Microbiology, Faculty of Biotechnology, and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors.forename: Mohd Termizi
authors.initials: MT
authors.lastname: Yusof
authors.affiliation: Malaysian Agricultural Research and Development Institute Seberang Perai, 13200 Kepala Batas, Pulau Pinang, Malaysia.
authors.forename: Azmi Abd
authors.initials: AA
authors.lastname: Razak
mesh_terms: D001203:Ascomycota / Q000145:classification* / Q000166:cytology / Q000235:genetics / Q000302:isolation & purification*; D016000:Cluster Analysis; D003433:Crosses, Genetic; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D049770:Genes, Mating Type, Fungal; D008296:Malaysia; D012275:Oryza / Q000382:microbiology*; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000382:microbiology; D012340:RNA, Ribosomal, 5.8S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014404:Tubulin / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D012340:RNA, Ribosomal, 5.8S; D014404:Tubulin
keywords: Oryza sativa; Pleosporaceae; mating type; phylogeny; teleomorph stage