The Bacteria screening medium is a rich medium containing sucrose as the energy source, vitamins from yeast extract, and amino acids from hydrolyzed casein. This medium is used to identify contamination in plant tissue cultures that may otherwise go unnoticed. The bacteria screening medium is not intended to support the growth of plant tissues, therefore tissue inoculation is not suggested. Simply stab plant tissues into medium or swipe across the surface of the medium.

The bacteria screening medium is also called Phyto Casein Hydrolysate Sucrose Agar.