Variation and Distribution of Endophytic Fungus, Neotyphodium typhinum, Isolated from Agropyron ciliare var. minus (Aokamojigusa) around the Coast Land of Lake Biwa

Abstract

Seeds of Agropyron ciliare var. minus (=Elymus racemifer) were collected at the coast land around Lake Biwa, and tested for mycelial infection of the aleurone layer with Aniline Blue staining method. Most of seed samples showed high infection levels (more than 50% in fected), except for four samples from Adogawa and Wanigawa (west coast), Anegawa (north coast), and Serikawa (east coast). When fungal endophytes were isolated on PDA medium, some developed straight-type mycelia, while others developed waved-type mycelia. Because both types of mycelium produced Acremonium-type conidia, they could be Neotyphodium endophytes. Waved-type endophyte prevailed over straight-type in the coastal distribution. Straight-type endophyte could not be detected on west coast land and Okishima Island. Plants harboured with each type of endophyte, i.e. straight-type or waved-type, developed choke symptoms in spring.