Author
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KISS, LEVENTE - HUNGARY |
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Submitted to: BARC Poster Day
Publication Type: Abstract Only Publication Acceptance Date: 2/27/1999 Publication Date: N/A Citation: N/A Interpretive Summary: N.A. Technical Abstract: Pycnidial fungi belonging to the genus Ampelomyces are common intracellular hyperparasites and also the most studied biocontrol agents of powdery mildew fungi, biotrophic parasites of many plants. In spite of intensive studies, their systematics and ecology are still controversial. Firstly, they are generally considered as belonging to a single species, A. quisqualis. However, recent RFLP analysis of the nuclear rDNA ITS region in a worldwide collection of Ampelomyces isolates showed the existence of seven RFLP groups (1). Divergence values among ITS sequences suggested that isolates belonging to different RFLP groups may represent different taxa. When Ampelomyces ITS sequences were analyzed by cladistic methods with sequences of other ascomycetous fungi, they formed two clades in the Dothideales suggesting that the taxa in the two clades are not closely related and possibly not even congeneric (2). Secondly, although Ampelomyces spp. Are generally considered to be common hyperparasites of all species of the Erysiphaceae, they were not known on graminicolous powdery mildews until recently (3). Their natural occurrence in these fungi is rare compared with their incidence on powdery mildewed dicotyledons (4). These results refute two basic dogmas about the biology of Ampelomyces and could lead to the development of a new biofungicide against powdery mildews. |