Plant Preservative Mixture (PPM™)

• At optimum doses, PPM™, which stands for Plant Preservative Mixture™, is an extremely effective Preservative/Biocide, yet does not impair in vitro seed germination, callus proliferation and callus regeneration.
• PPM™ prevents the germination of both bacteria and fungi spores. It is heat stable and therefore can be autoclaved with the media.
• PPM™ can be, and should be used as a standard ingredient in plant tissue culture media, and is also substantially less expensive than commonly used antibiotics.
• While PPM™ was principally designed to inhibit airborne contamination, waterborne contamination, and contamination introduced from human contact, it can also -- in many cases -- be used to reduce endogenous contamination.
• PPM™ does not affect the genetic profile of the plants.

• Controller of microbial airborne contamination.
• Manager of microbial waterborne contamination.
• Inhibitor of endogenous contamination.
• Enhancer of the success of culture experiments.
• Maintainer of the viability of in vitro seed germination.
• Promoter of callus proliferation.
• Supporter of callus regeneration.
• Ensurer of the stability of tissue culture media.

General Dosage levels:

1. With the exception of endogenous contamination, the recommended dose range is 0.05%-0.2%. (For callus proliferation, organogenesis and embryogenesis, the recommended range is 0.05-0.075%.) To eliminate higher endogenous contamination densities, higher doses of PPM™ are needed.
2. (a) For explants: gently and routinely shake / stir 1 cm. long explants (or shorter) for 4-12 hours in 4-5% v/v PPM™ solution supplemented as above with 3x MS strength basal salts without Tween 20.Without rinsing, insert into a medium supplemented with 0.05 - 0.1% PPM™ for herbaceous plants and 0.2% PPM™ for woody plants.  (b) For ornamental plants only -- For tubers, bulbs and scales: shake / stir the entire tuber/ bulb / scale in bleach. Rinse with water (can be done under non-sterile conditions). Slice the tuber / bulb /scale to thin slices. Shake / stir for 12-24 hours in 4- 5% PPM™ solution supplemented with full strength basal salts without pH ing & Tween 20. Without rinsing, insert into a medium supplemented with 0.1 -0.2% PPM™.