多功能列当生防镰刀菌的筛选及种类鉴定

Isolation and Identification of Multifunction Bio-control Agent Fusarium against Orobanche cernua

从河北省张家口地区种植的烟草上采集的感病弯管列当植株,从中分离得到20株镰刀菌,采用孢子悬浮液浸根和灌根法对小麦、玉米、棉花、向日葵、番茄、烟草、辣椒、茄子、西瓜、甜瓜等作物和蔬菜进行了安全性检测,筛选出对主栽作物和蔬菜安全且具有促生作用的4个菌株。其中菌株Br-2对烟草、辣椒、西瓜有显著促生作用,且对弯管列当的防治效果最好:施用菌株Br-2后烟草、辣椒、西瓜增高分别为123.53%、62.16%、28.95%;其发酵上清液对弯管列当种子萌芽抑制率为71.79%;小区试验中对弯管列当的寄生率防效为50%,寄生度防效为79.38%;田间试验中对弯管列当的寄生率防效为58.27%,寄生度防效为75.70%。形态学和分子生物学鉴定结果表明菌株Br-2为尖孢镰刀菌。

Twenty Fusarium strains were isolated from the diseased Orobanche cernua in Zhangjiakou District, Hebei Province. Safety analysis with the root immersion and inoculation method demonstrated that four strains were relatively safe and had evident growth-promoting effect on the tested crops and vegetables（wheat, maize, cotton, sunflower, tomato, tobacco, pepper, eggplant, watermelon, melon）. Among all the four strains, strain Br-2 had significant effect on promoting the growth of tobacco, pepper and watermelon, and it also had the best control effect to O. cernua： The plant height of tobacco, pepper and watermelon increased 123.53%, 62.16% and 28.95%, respectively, after applying strain Br-2. The fermentation supernatant of strain Br-2 could inhibit seed germination of O. cernua by 71.79%. In plot experiments, the parasitic rate of strain Br-2 to O. cernua was 50% and the parasitic degree was 79.38% in field trials.