Submitted to: Mycological Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/8/1997
Publication Date: N/A
Interpretive Summary: There are several species of grasses that live with molds. The mold lives inside the grass where it obtains nourishment; the grass receives benefits from the fungus such as protection from insect and cattle grazing. These relationships are referred to as mutualistic since both organisms benefit from living together. Usually the mold lives throughout the inside of the grass and is referred to as an endophyte. The nature of these relationships, especially to cattle, was established by scientists at RRC. This research provided the focus of several important technological uses of infected grasses and their molds. This technology is referred to as endophyte-enhanced grasses. We describe here an association by the mold Myriogenospora atramentosa with several grasses that differ from the basic endophytes in that they live in very localized areas of the plant. This localizing habit is referred to as epibiotic. The mold lives in association with the grass but prevents it from producing seed. We also report that these associations are apparently associated with tropical grasses, particularly sugarcane and its relatives. This is important because it indicates that this mold is not an endophyte, and that this mold induces grass sterility and should not be used for grass breeding programs. Thus, this relationship is referred to as pathogenic, which indicates that Myriogenospora and other such molds should not be used in programs of endophyte-enhanced grasses.
Technical Abstract: The epibiotic fungus Myriogenospora atramentosa belongs to the ergot alkaloid producing tribe Balansieae (Clavicipitaceae). This parasite produces partial to complete sterility of host plants. In South Carolina, it is reported for the first time growing on Paspalum notatum (bahiagrass), Panicun hemitomon, and on two unreported host species, Panicum scoparium and Paspalum urvillei. It is also reported for the first time o Erianthus brevibarbis, E. contortus, and E. giganteus, and on hybrids produced by crosses with Erianthus spp. during a current sugarcane breeding program. An updated host and geographic range are compiled for M. atramentosa. Two related species of Balansieae and their host species are also reported occurring in several counties of South Carolina and states in the Southeast.