Submitted to: Mycologia
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 2, 1996
Publication Date: N/A
Interpretive Summary: Grasses evolved with one large group of fungi. Each species of fungus is associated with a grass species, and the survival and other ecological features of grasses are enhanced. These fungi are referred to as endophytic since they live within the plant. This group of fungi consists of several subgroups, and each subgroup shares certain characteristics in common. These subgroups appear to form a natural grouping but there are several inconsistencies using only classical morphological features. One of the major desires is to transfer an endophyte to an uninfected grass species for enhanced grass performance, especially in turf grasses. Scientists at RRC and Rutgers collaborated to determine if these subgroups can be defined at the molecular level. RRC scientists provided most of the molecular data used to support and clarify the traditional morphological studies. It was established that one subgroup studied actually consisted of at least two subgroups, while other fungi within this subgroup may not belong to either. It was also established that fungi that are endophytic are more highly evolved than those that are found localized in areas of leaves. It suggests that these fungi evolved with their hosts and host compatability may make it impossible to transfer lower evolved endophytic fungi to highly evolved grasses.
Technical Abstract: Balansia subgenus Dothichloe is defined to include only species of graminicolous Clavicipitaceae that are endophytic, form stromata on leaves or culms, and produce nonstipitate black ascomata. B. epichloe, B. gaduae, B. henningsiana, B. nigricans, and B. strangulans. Phylogenetic relationships in Dothichloe are evaluated through examination of ribosomal DNA ITS (internal transcribed spacer) sequence data. It is concluded that at least two subclades are evident in the subgenus, including the B. gaduae B. nigricans subclade and the B. henningsiana/B. strangulans subclade. Sequence divergence of B. epichloe and variable placement of B. aristidae between the two subclades in different analysis make it difficult to confidently assign them to either subclade. A dichotomous key to Dothichloe is included along with descriptions of B. aristidae, B. epichloe B. gaduae, and B. henningsiana.