the conserved meiotic recombination machinery of eukaryotic cells. The study indicated that the Glomus species contain 51 genes encoding all the tools necessary for meiotic recombination and associated DNA repair processes. In particular, these species have seven genes that encode proteins whose only known function is in meiosis, including Dmc1 that is a meiosis-specific recombinase. Since meiosis is considered to be a hallmark of sexual reproduction, it might be expected that a sexual stage or a sexual apparatus should be present. However, as yet, none has been identified. In addition, mating type gene homologues and a putative sex hormone-sensing pathway were detected in these fungi. Based on these findings it was suggested that Glomus species may be able to undergo a cryptic sexual cycle. The population structure of Glomus etunicatum suggests that clonal expansion plays an important role in the ecological success of Glomus species, and that gene exchanges are not completely absent, although likely very rare. Agricultural significance Several species of Glomus, including G. aggregatum, are cultured and sold as mycorrhizal inoculant for agricultural soils. One species, G. macrocarpum (and possibly also G. microcarpum), causes tobacco stunt disease. Species Glomus aggregatum Glomus albidum Glomus ambisporum Glomus brazillanum Glomus caledonium Glomus coremioides Glomus claroideum Glomus clarum Glomus clavisporum Glomus constrictum Glomus coronatum Glomus deserticola Glomus diaphanum Glomus eburneum Glomus etunicatum Glomus fasciculatum Glomus fistulosum Glomus fragilistratum Glomus geosporum Glomus globiferum Glomus heterosporum Glomus hoi Glomus intraradices Glomus lacteum Glomus lamellosum Glomus luteum Glomus manihotis Glomus microaggregatum Glomus monosporum Glomus mosseae Glomus multicaule Glomus pansihalos Glomus pustulatum Glomus sinuosum Glomus spurcum Glomus tortuosum Glomus trimurales Glomus verruculosum Glomus versiforme Glomus viscosum See also Glomalin Glomeromycota References "Genus Glomus" at the Catalogue of Life Checklist International Culture Collection of (Vesicular) Arbuscular Mycorrhizal Fungi Symbiotic Fungi Glomerales Fungus genera Taxa named by Edmond Tulasne