The Plate Count in Aquatic Microbiology

The application and inherent difficulties of the traditional plate count technique and its variations are presented. While the plate count has been, and continues to be, used for enumeration of microorganisms in natural waters, recent criticisms of the technique appear increasingly in the literature. Accordingly, the quantitative nature of the plate count is discussed in relation to limitations of the procedure and current alternatives for microbial enumeration. Constant evaluation of newly evolving quantitative procedures for the determination of microbial numbers, biomass, and activity is recommended to prevent the "standardization" of techniques which, like the plate count, subsequently become subject to debate as to their appropriateness in ecological studies. The plate count is still seen as a valuable tool for its originally intended purpose and should be supplemented and reevaluated in conjunction with contemporary quantitative methods.