福岡県内サラダナ産地で分離されたレタス根腐病菌レース3の体細胞和合性群

抄録

Fusarium oxysporum was isolated from farmers plastic houses, in which root rot of butter-head lettuce had spread, in Fukuoka prefecture. Eighty-seven isolates of F. oxysporum f. sp. lactucae race 3 were divided into four vegetative compatibility groups(VCGs). and all 119 isolates were obtained from diseased plants belonging to one of the four VCGs. VCG 1 was perfectly independent of the other VCGs. However, many isolates assigned into VCG 2, VCG 3. or VCG 4 formed not only strong heterokaryons with their own testers, but also strong or weak ones with testers of other VCGs. Some pathogenic isolates formed bluish-purple or bluish-brown colonies with dark gray aerial hyphae on a selective medium. Fo-W1. These isolates belonged to VCG 1. As a result, the pathogen could be distinguished from other F. oxysporum isolates by vegetative compatibility and the characteristics of colonies on Fo-W1.