The antifungal activity of secondary metabolic products from Xenorhabdus nematophilus YL001

This study investigated the antifungal activity of secondary metabolic products from Xenorhabdus nematophilus YL001 in vitro and in vivo. The results indicated that the supernatant of the bacteria broth inhibited mycelial growth of 15-species plant-pathogenic fungal in vitro. It especially could markedly inhibited the mycelial growth to Botrytis cinerea and Phytophthora capsici. Their EC_ 50 value against Botrytis cinerea and Phytophthora capsici were 53.54 mg·L~ -1 and 90.39mg·L~ -1 , respectively. The spore germination EC_ 50 value against Botrytis cinerea and Alternaria alternata were 16.97mg·L~ -1 and 21.87 mg·L~ -1 , respectively. In addition,protective effect and therapeutic effect of the fermentation products diluted 10 times against the Botrytis cinerea were 74.98% and 63.50% on tomato, respectively. Finally protective effect and therapeutic effect of the fermentation products against the Botrytis cinerea were 65.11% and 54.64% on cucumber in potted, respectively. The decrease of spore germination rate and the abnormal hyphal growth was observed under microscope.