Estimation of the maximal population frequency of “alien” biotypes taking into account a priori data

A method is described for calculating the probability that the percentage of “alien” biotypes is higher than a specified threshold (e.g., 5%) in a population in which a certain number of “alien” biotypes has been found preliminarily. The method is based on the Bayesian approach; it assumes that the researcher has preliminary (a priori) information on the frequency of these biotypes. This a priori information makes it possible to estimate the aforementioned probability more accurately than is possible with the use of the standard binomial estimation. The method is illustrated by the results of the estimation of cultivar purity in batches of stock and foundation seeds of spring barley with the use of protein markers.