发光杆菌Photorhabdus sp.HBgy13菌株对4种蔬菜病原菌的抑菌活性

Inhibiting effect of Photorhabdus sp. HBgy13 against four vegetable pathogenic fungi

测定了发光杆菌属Photorhabdussp.HBgy13菌株对番茄菌核病菌(Sclerotiniasclerotiorum),冬瓜枯萎病菌(Fusariumoxysporum)、萝卜褐腐病菌(Rhizoctoniasolani)、黄瓜灰霉病菌(Botrytiscinerea)等4种蔬菜病原真菌的抑制作用,并对该菌株发酵液中抑菌活性成分的理化特性及滤液活性进行了研究。结果表明:该菌株对黄瓜灰霉病菌和萝卜褐腐病菌有较好的抑制作用;该菌株在200r/min,28℃,96h发酵后,抑菌活性达到最大,抑菌圈分别达到2 28cm和2 74cm;发酵液经50℃处理10min后,对黄瓜灰霉病菌和萝卜褐腐病菌抑制活性分别下降34 2%、43 7%,经80℃处理10min后,对这2种病菌的抑菌活性消失,说明发酵液中的抑菌活性成分不耐高温;发酵液经紫外线处理30min后抑菌活性完全消失;发酵液pH值为7时,抑菌活性最强。滤液对黄瓜灰霉病菌和萝卜褐腐病菌的抑制活性分别为原液的33 0%和33 2%。

The Photorhabdus sp. HBgy13 associated with entomopathogenic nematodes was isolated from Heterorhaditis sp. HBgy.The inhibiting effect of the bacterium isolate on four species of vegetable pathogenic fungi was tested. The result showed that this isolate appeared antibiotic activity against Botrytis cinerea and Rhizoctonia solani. The culture broth has the highest effect in fermenting at 200 r/min,28℃, 96 h in this experiment. The factors of influencing antibiotic activity of the isolate HBgy13 was tested too.The results appeared that the antibiotic substances against Botrytis cinerea and Rhizoctonia solani were susceptible to high temperature(℃) and ultraviolet. The pH =7 is optimal. The antibiotic activity of filtrate was only 330% of the fermented broth.