PRECISION OF GENETIC-RELATIONSHIP ESTIMATES BASED ON MOLECULAR MARKERS

Genetic progress through selection is directly related to the amount o f variability present in the population and the quality of genes contr ibuted by the parents. Genetic relationships between lines were studie d using DNA marker-based estimates of genetic similarity. A statistica l methodology using the width of a confidence interval was developed t o determine the number of probes to be surveyed and the precision in t he estimation of genetic distance between pairs of cultivars. Precisio n was affected by type of genetic distance used, the number of cultiva rs, and amount of genetic diversity present in the studied group. The width of a (1-alpha)% confidence interval decreased as the number of R FLP fragments increased. Oat and wheat diversity studies were used to illustrate the methodology.