Skip to main content
ARS Home » Research » Publications at this Location » Publication #235310

Title: Ulocladium cantlous sp. nov. isolated from Northwest China: morphology and molecular phylogenetic position

item Oneill, Nichole

Submitted to: Mycologia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/25/2009
Publication Date: 3/11/2010
Citation: Wang, Y., Pei, Y., Oneill, N.R., Zhang, X. 2010. Ulocladium cantlous sp. nov. isolated from Northwest China: morphology and molecular phylogenetic position. Mycologia. 102(2):374-383.

Interpretive Summary: Fungus diseases caused by species of Ulocladium and Stemphylium severely reduce yields and quality in important forage and food crops, including chickpea, clover, alfalfa, and vegetables. The fungi cause leaf, stem, and pod necrosis in humid climates throughout the world. It is important to know specifically which fungi are causing certain diseases so that control measures can be developed and quarantine procedures implemented when needed. Many of these fungi are difficult to distinguish from one another based on their morphology alone, as seen microscopically. We compared strains causing a disease in cucumber, using molecular DNA sequencing and morphology. The research resulted in the identification and characterization of a new pathogen species, closely related to but distinct from Stemphylium and other Ulocladium spp. The research will enable scientists, breeders, and industry to identify the specific causes of diseases in forage and vegetable crops, and lead to implementation of appropriate disease control strategies.

Technical Abstract: A new species of Ulocladium was isolated from diseased leaves from two Cucumis spp. growing in Sinkiang and Gansu Provinces of China. Conidia were isolated from diseased leaf areas, grown in single-spore pure culture, and conidia harvested 1, 3, and 7 days after incubation for morphological comparisons. The morphology of this species resembles that of U. botrytis, U. consortiale and U. cucurbitae. However it is distinguished from these three species by the size range of the obovoid or broadly ellipsoidal conidia, and the length of conidiophores. U. cantlous also exhibits the multiplex conidium morphology which is often associated with the U. atrum species group. A taxonomic description of U. cantlous, comparisons with related species in this genus, and a species phylogeny based on the partial nucleotide sequence of the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene are provided. The Alternaria alternata major allergen (Alt a 1) gene is also discussed.