24小时热门版块排行榜    

查看: 790  |  回复: 5
当前只显示满足指定条件的回帖,点击这里查看本话题的所有回帖

zhangjingwjs

新虫 (小有名气)

[交流] 问题 已有2人参与

Nowadays, I used the diluted spreading method to evaluate the density\population of the soil.
Firstly, 0.5 g of fresh soil was collected and put in a triangular flask with some glass beads.
Then shaking for 15 min, subsequently cooling down about 2 min, next smoking 10 ml into the 15 ml tubes, which was treated as 10-dilution solution.
then i ml from the 10-1 was taken and transferred to another 9 ml sterile water, which was as 10-2.
In a similar way, I got 10-3, 10-4, 10-5, 10-6, 10-7, 10-8, 10-9.
Finally, 1 ml of each diluted solution was spreading on the R2A plates, then put in the stove at 37 degree temperature for two days. three replicates of each treatment.
Now, my question is that why I found there was nothing on some plates but not all, for example one of the 10-6 and 10-5.
while on the 10-9 plates, there were much bacteria colonies, which was so strange.
Now i am wondering What happened during the operation <>
who knows ? please share your experiences here, thanks in advance!

[ Last edited by zhangjingwjs on 2016-6-20 at 00:39 ]
回复此楼

» 本帖已获得的红花(最新10朵)

» 猜你喜欢

已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
4楼2016-05-28 21:28:07
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
查看全部 6 个回答

yangli_sisi

铜虫 (小有名气)


小木虫: 金币+0.5, 给个红包,谢谢回帖
maby your dilution is not enough, the density of each planet is not proportional

发自小木虫Android客户端
2楼2016-05-27 18:46:13
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

yangli_sisi

铜虫 (小有名气)


小木虫: 金币+0.5, 给个红包,谢谢回帖
when you make a new solution ,you should shake for a while

发自小木虫Android客户端
3楼2016-05-27 18:51:31
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

zhangjingwjs

新虫 (小有名气)

引用回帖:
3楼: Originally posted by yangli_sisi at 2016-05-27 18:51:31
when you make a new solution ,you should shake for a while

I did a second time, of course each dilution three replicates, but the new problem is in the same dilution, some of the plates can grow bacteria , but some can not, what's the reason >? thanks YangLi
5楼2016-05-30 16:10:40
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖
普通表情 高级回复 (可上传附件)
信息提示
请填处理意见