Endophytes of annual and hybrid ryegrasses

Abstract

Endophytes of Lolium spp. were studied, with particular emphasis on those in annual and hybrid ryegrasses. A previously undescribed Acremonium-like species of endophyte has been isolated from Lolium multiflorum, Lolium .times. hybridum cv. Grasslands Manawa, and six species and varieties of annual Lolium spp. This fungus has been cultured and successfully inoculated into seedlings of L. multiflorum. Mycelium occurs in nodes, leaf sheath bases, culms, and seeds of infected plants. It is common in most New Zealand cultivars and ecotypes of L. multiflorum but not in cultivars from overseas. Mycelium and a second endophyte, a Gliocladium-like sp., occurred in plants of L. multiflorum, L. .times. hybridum, and L. perenne, but mycelium of a third endophyte, A. lolii, was found only in L. perenne and L. .times. hybridum cv. Grasslands Ariki. Seedings of L. multiflorum, L. temulentum, and ''Grasslands Manawa'' were artificially infected with A. lolii. Mycelium of this fungus was not confined to the base of leaf sheaths of these plants but grew throughout the sheath.