Glomus aurantium and G. xanthium, new species in Glomeromycota.

摘要

This paper describes 2 new ectocarpic arbuscular mycorrhizal fungal species, Glomus aurantium and G. xanthium (Glomeromycota), discovered in the Mediterranean Sea dunes located in Israel, Greece, Italy, and Majorca, Spain. Mature spores of G. aurantium are deep orange, globose to subglobose, (70-)98(-120) micro m diameter, or ovoid, 80-120x110-150 micro m. Their wall consists of a permanent, flexible to semiflexible, hyaline outermost layer, easily separated from a laminate, deep orange middle layer, and a flexible hyaline innermost layer. Spores of G. xanthium usually are tightly adherent to the roots and frequently occur within the roots. They are light yellow to ochre, globose to subglobose, (23-)50(-70) micro m diameter or ovoid, 20-55x45-100 micro m, and have a spore wall with a rigid, semi-permanent, hyaline to light yellow outermost layer adherent to a rigid, permanent, hyaline middle layer, and a laminate, light yellow to yellow ochre innermost layer. Both species form vesicular arbuscular mycorrhizas in single species cultures with Zea mays. Analysis of ITS and LSU nuclear rDNA in spores placed G. aurantium sequences in the G. versiforme group, while G. xanthium sequences were aligned with those in Glomus Group A.