Bragard C., Verdier Valérie, Maraite H. (1995). Genetic diversity among Xanthomonas campestris strains pathogenic for small grains. Applied and Environmental Microbiology, 61 (3), p. 1020-1026. ISSN 0099-2240.
Titre du document
Genetic diversity among Xanthomonas campestris strains pathogenic for small grains
Année de publication
1995
Type de document
Article
Auteurs
Bragard C., Verdier Valérie, Maraite H.
Source
Applied and Environmental Microbiology, 1995,
61 (3), p. 1020-1026 ISSN 0099-2240
A collection of 51 Xanthiomonas campestris strains from throughout the world was studied to detect and assess genetic diversity among pathogens of small grains. Isolates from barley, bread wheat, bromegrass, canary grass, cassava, maize, orchard grass, rice, rough stalked meadow grass, rye, timothy, and triticale were analyzed by pathogenicity tests on bread wheat cv. Alondra and barley cv. Corona, indirect immunofluores cence, and restriction fragment length polymorphism (RFLP)). Three probes were used for the RFLP analysis. They were an acetylaminofluorene labelled 16S+23S rRNA probe from Escherichia coli and two 32P labelled restriction fragments from either piashidic (pBSF2) or chromosomal (pBSS) DNA of X campestris pv. manihotis. Strains clustered in 9 and 20 groups with the rRNA probe and the pBSF2 DNA probe, respectively. Strains of X. campestris pv. graminis, X. campestris pv. phleipratensis, and X. campestris pv. poae are shown to be related but are also distinguishable by RF'LP patterns, serolog, and pathogenicity on bread wheat. Strains pathogenic only for barley and not for wheat grouped together. Another group is temporarily designated deviant X. campestris pv. undulosa. These South American isolates from bread wheat did not react by indirect immunofiuorescence and produced atypical lesions in pathogenicity tests. The results stress the need to perform pathogenicity tests before strains are named at the pathovar level. The importance of the different probes used for epidemiological studies or phylogenetic studies of closely related strains is underlined.
