アズキに対するアズキ萎凋病菌胞子発芽液の毒素活性
2000 年 2000 巻 51 号 p. 40-43
詳細
2000 年 2000 巻 51 号 p. 40-43
Fusarium oxysporum f. sp. adzukicola, the causal agent of adzuki bean (Vigna angulari) wilt, produced phytotoxic substances to azuki bean in spore germination fluid (SGF). Stem cuttings of susceptible cultivar“Hayate-shozu” treated with 20-fold concentrated SGF showed symptoms similar to the diseased azuki bean, i.e., vein necrosis and vascular browning. Growth of treated stem cuttings was also inhibited. Symptoms induced by SGF differed from chlorosis induced by 100 ppm fusaric acid. SGF toxic activity remained after heat treatment at 60°C for 2 hr or at 100°C for 30 min. SGF induced symptoms in both susceptible cultivar “Erimo-shozu” and resistant cultivar “Kitano-otome”. We surmise that toxic substances are not major pathogenesis determinants in F. oxysporum f. sp. adzukicola.
