Rapid method for selecting appropriate solid media for the enumeration of aerobic micro-organisms.

A quick and cheap method for selecting appropriate solid culture media has been devised. It consists in the rapid picking of fragments of test colonies with the aid of a rubber strip in which pins are fixed in parallel, dispensing up to 8 colonies simultaneously in the wells of a Microtiter plate and streaking 4 strains at the same time on square Petri dishes containing the media under comparison. The approximate diameters of well-isolated colonies are measured with the aid of a series of calibrated spots. The results corresponded with those given by the spiral plate method used as a reference for colony count and diameter measure.