Estimation of heritability and prediction of selection response in plant populations

A unified presentation, a synthesis, and an evaluation of the methods employed in the estimation of heritability in plants are presented. Asexual, cross‐fertilizing, and self‐fertilizing diploid species, as well as annual and perennial ones, are considered. All broad‐ and narrow‐sense heritabilities are defined on individual and family bases for prediction of response to selection for a target population of environments in space and time. Narrow‐sense heritabilities are defined in cross‐fertilizing species for expected response to variations of mass, half‐sib, and full‐sib family selection for the next generation and the long term, and similarly in self‐fertilizing species. The use of both collateral and lineal relatives to estimate heritability is discussed, and the biases present in the estimators are given. Many departures and variations of the common procedures are discussed. The standard errors of heritability estimators and confidence intervals are presented.