Changes of Endophyte Infection Frequency in Turf of Northeastern Honshu, Japan

Abstract

SAIGA, S., A.MAEJIMA, S.YOSHIDA and M.TSUIKI(2001):Changes of endophyte infection frequency in turf of northeastern Honshu, Japan. Grassland Science 47, 478-483. This study follows the change of endophyte infection frequency in turf sown with endophyte-infected perennial ryegrass and tall fescue seed from fall in 1998 to fall in 2000. Three golf courses (GC) and two sports grounds (SG) were selected for an investigation of the incidence of endophyte in Iwate prefecture. At each site 50 plants were taken along a 50m line transect and endophyte presence at the interior epidermis of a leaf sheath was determined microscopically. In perennial ryegrass, the incidence of endophyte infection varied greatly amongst the different sites. The incidence of endophyte infection at two sites did not change greatly and remained as low level. However, the incidence of infection at Mizusawa GC and Miyako SG increased rapidly up to 90% in 2000. The incidence of endophyte infection of tall fescue was lower than that of perennial ryegrass, but at Miyako SG the incidence of endophyte infection frequency increased in the fall of 2000. The difference in changing the incidence of infection among sites seems to have caused by soil structure. In conclusion, endophyte-infected plants can survive and retain a high incidence of endophyte in dry and hot conditions even in northeastern Honshu, Japan.