Date: Fri, 19 Sep 1997 16:52:54 -0700 From: Rick Walker <walker@cutter.hpl.hp.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg3608$foo@default> Subject: RE: CP TC media problems
> OK all you TC type folks, I'm looking for help :-)
>
> The last 3 batches of media I have made have had the consistancy of runny
> pea soup when cooled. I'm not sure what I'm doing wrong.
Agar is a natural product extracted from seaweed. It varies in gel
strength from batch to batch. It can be expected that you will need
somewhere between 6-8 g/L to achieve proper gelling. Many CP TC recipes
specify 6g, but the real guideline is to use the *minimum* concentration
that will give you good gelling. If you've got some weak agar, you'll
likely need to increase the agar concentration to 7 or 8g/L.
You could avoid this by using some of the synthetic media formulas
(Phytomax, et al.)... Alternatively, you could just make a few trial
runs when you buy agar from a new manufacturing lot.
If you really don't want to be bothered, then just use 8g/L all the
time. The down side will be a firmer gel that will be harder for the
roots to penetrate into. You might also have less free diffusion of
metabolic waste products into the gel, so your plants might not grow
as quickly.
Best regards,
-- Rick Walker
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:31:10 PST