[Drosophila] Re: culture problems

Mark Thorson via dros%40net.bio.net (by nospam from sonic.net)
Fri Aug 17 14:34:57 EST 2012

dr julien colomb wrote:
> you are using a very complicated food, why not using standard corn meal
> medium?

Standard media are cooked and have a mold inhibitor.
I want an uncooked medium to save time (I'm making a
batch every day, and cooking would probably double the
time making a batch) and for my application I don't
want any mold inhibitor.

> The fact that the adults die and not the larvae is peculiar.
> I never had that before, but it reminds me of a story with pesticides.
> In my former labs, we had to change the corn because the one we used was
> not produced anymore. We took bio-cornmeal and flies started to die: the
> corn was not insecticides free... Maybe you have such a problem?

Early death of the adults is a sporadic problem.
It will affect some culture vessels in a batch but
not others.  If my medium was contaminated with
insecticide, I'd expect every vessel to be affected.

> We also have problems sometimes with the food, but then the larvae are
> dying not the adults. It normally disappear after some time without us
> knowing why the problem was there...

I certainly know what that feels like.  This isn't
like chemistry, where you mix the chemicals and they
always do the same thing every time.

> I hope it can help.

Thanks, I need all the ideas I can get.  My latest
attempts to solve the problems have been to reduce
the amount of food by half and to cut the bananas
into smaller pieces.  The last six batches look good,
with few adult early deaths, but it will be another
week or more before I know how well they produce.

More information about the Dros mailing list