The Prediction of Selection Response in A Self-Fertilizing Species II. Family Selection

Abstract

The response to between-and within-family selection is considered for self-fertilizing populations. For a general genetic model involving m alleles at each of k loci the expected responses are written as the sum of (1) the natural change in mean due to decreasing heterozygosity, and (2) a component which is a function of the genetic and environmental variances within an unselected population. A single-locus model is then considered and the expected responses are written in terms of para-meters of the base population. General expressions are given for the ultimate response following relaxation of selection and these are interpreted in terms of the single-locus model. In the final section the efficiencies of the various methods are investigated. In general, within-family selection is relatively inefficient while between-family selection is usually to be preferred over the selection of individuals or the more complex method of combined selection.