Gene Flow Analysis of Phytophthora porriReveals a New Species: Phytophthora brassicaeSp. Nov.
In: European Journal of Plant Pathology, Jg. 108 (2002), Heft 1, S. 51-62
Online
serialPeriodical
Zugriff:
Isozyme analysis and sequence analysis of the internal transcribed spacer regions (ITS-1 and ITS-2) and the 5.8S subunit of the ribosomal DNA gene repeat were used to examine whether isolates of Phytophthora porrifrom Alliumand Brassicarepresent a single homogeneous species. Twenty-six strains of P. porri, 16 strains isolated from the genus Allium, and 10 strains isolated from the genus Brassica, were analyzed using malate dehydrogenase (MDH), isocitrate dehydrogenase (IDH) and lactate dehydrogenase (LDH), represented altogether by four putative loci (Mdh-2, Idh-1, Idh-2, and Ldh-2). Isozyme analysis revealed that strains isolated from Alliumcontained five private alleles at three isozyme loci (Ldh-283, Ldh-2104, Idh-1108, Idh-1112, and Idh-298), whereas six different alleles were observed at four isozyme loci (Ldh-285, Ldh-2100, Ldh-2114, Idh-1100, Idh-2100, and Mdh-2111) in strains obtained from Brassica. The heterozygosity at the Ldh-2locus, differing in allele composition, however, between strains from Alliumand Brassica,was present in all strains, indicating that it is probably fixed. Sequence analysis of the ITS regions and the 5.8S subunit showed consistent differences between isolates from Alliumand isolates from Brassica. Based on isozyme data, ITS sequence analysis and formerly published differences in restriction enzyme patterns of mitochondrial DNA, morphology and pathogenicity, it was concluded that the isolates of P. porriFoister did not represent a homogeneous species. Isolates from Brassicaconstitute a distinct species which is described here as P. brassicaesp. nov. It was inferred from isozyme patterns, which were in no case intermediate between the two species, that P. porriand P. brassicaedo not hybridize and are reproductively isolated by barriers to gene flow.
Titel: |
Gene Flow Analysis of Phytophthora porriReveals a New Species: Phytophthora brassicaeSp. Nov.
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Autor/in / Beteiligte Person: | Man in 't Veld, Willem ; de Cock, Arthur ; Ilieva, Elena ; André Lévesque, C. |
Link: | |
Zeitschrift: | European Journal of Plant Pathology, Jg. 108 (2002), Heft 1, S. 51-62 |
Veröffentlichung: | 2002 |
Medientyp: | serialPeriodical |
ISSN: | 0929-1873 (print) ; 1573-8469 (print) |
DOI: | 10.1023/A:1013929110325 |
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