I was going to wait on posting this data for another couple of weeks. However, in response to someone's faith, I thought it better to share the positive results thus far. Lest he break out the votive candles and start praying over cultures.....
Currently, I have been using PPM very liberally - like water - and I refilter after each use with 0.2uM sterile filters (which are more expensive than the PPM itself). What I found when I searched for "methylisothiazolinone" is Dow Kathon CG/ICP (formulations I and II). And then we return to where I was months ago before ever embarking on plant TC: printing out patents, journal articles, and reading everyone's post on the forums. I have to agree PPM is not cheap, but it is not that expensive either. Still, my 30ml bottle is dwindling down so I set off to make some in house with off the shelf items. This is not to take business away from the parent company, it is just my nature.
The formulation can be found from the patent in the examples section: http://www.google.com/patents/US5750402
My homebrew is based off of Kathon CG/ICP I (in the ratio from the product insert and not the patent) and the two preservative listed (at 1/4 concentration listed on the patent). If you know chemistry and can find the solubility curves online, the pka of both preservatives is low and they both diassociate at lower pH. In order for it to be stable at 4C for long term storage, the preservatives need to be diluted.
PPM Tx: Sarracenia seeds were pretreated with H2O for 24 hrs and then subject to a 500ppm gibberlic acid treatment for 49 hours. Darlingtonia seeds were treated as the Sarracenia seeds minus the 24 hr H2O treatment. The seeds were sterilised in 1/3MS salts + 8% PPM (homebrew or commericial) for 3 hours on a orbital shaker.
Germination: Jen ppm germination occured 1-2 days faster than commercial PPM seeds. The germination rate thus far is in the table below:
There appears to be a table function missing here. The original post is on TF under the same title, if you would like to see the numbers.
Sarracenia Oreophilia Jen PPM
Sarracenia Alabamensis Jen PPM
Sarracenia Alabamensis Reg PPM
Darlingtonia Californica Siskiyou Jen PPM
Darlingtonia Californica Siskiyou Reg PPM
Darlingtonia Californica Del Norte Jen PPM
That's all kiddies