1种食用菌细菌隐性污染栽培种的菌种分离研究

研究1种以木屑为主要配方的食用菌细菌隐性污染栽培种的菌种分离。稀释涂布平板法分析细菌总数。栽培种捣碎后悬于无菌水，分别以短时(5 min)涡漩振荡、摇床振荡(180 r/min)、低温静置(4℃) 3种方式处理；灭菌纱布过滤收集、无菌水淋洗木屑接种至PDA斜面，培养使其生长。以未经处理木屑为接种物作为对照。结果显示栽培种细菌数为15500 cfu/g；对照（30支）以及采用短时涡漩振荡处理所接30支斜面全部细菌污染；摇床振荡1、2、3、4天纯化率分别为20%、30%、46.67%及63.3%；低温静置1、2、3、4天纯化率分别为3.3%、10%、46.67%和60%。以木屑为主要配方的细菌隐性污染栽培种悬于无菌水经1~4天振荡或浸湿再分离的基内菌丝分离法可有效分离纯化菌种。

Investigation on the Isolation of Pleurotus sp. from a Bacteria Contamination Sawdust-based Production Spawn

The work aimed to isolate the Pleurotus sp. from a bacteria contamination sawdust-based spawn. The number of bacteria was determined with the plate count assay. For the isolation of Pleurotus sp., the spawn was initially suspended in sterile water and then treated as follows: (1) vigorously mixed on a vortex mixer within five minutes; (2) kept continuously shaking at 180 r/min for 1-4 days; (3) kept to be static at 4℃ for 1-4 days. Next, the suspended spawn was collected by filtering using sterile gauze, and washed with sterile water. Finally, each slant was inoculated with a sawdust, allowing for growth at 25℃. As the control, the sawdust was directly inoculated into slants with one piece of sawdust per slant. The bacteria in the spawn determined were 15500 cfu/g. All the slants were found to be contaminated in the control. With the spawn vigorously mixed for 5 minutes before the isolation, no purified slants were observed. With shaking of 1, 2, 3 and 4 days, the success rate was 20%, 30%, 46.67%, and 63.3%, respectively. With kept to be static at 4℃ for 1, 2, 3 and 4 days, the success rate was 3.3%, 10%, 46.67%, and 60%, respectively. We conclude that mushroom strain can be effectively isolated and purified from bacteria contamination sawdust-based spawn using sawdust as inoculums by keeping spawn static or shaking in sterile water for 1-4 days before the isolation with the method of substrate mycelium isolation.