Inherritance of growth and other agronomic traits in two oat (avena sativa l.) Crosses

Abstract

Evaluating the inheritance of growth traits should assist plant breeders in determining its usefulness as a selection criterion for grain yield improvement. Three oat cultivars, 'Stout', 'Lodi' and 'Marathon' were chosen as parents on the basis of dry matter accumulation. Stout was early and produced high postheading dry matter. Lodi and Marathon were late anf produced high dry before heading, but were not high in postheding dry matter production. Two oat crosses (Lodi x Stout and Maarathon x Stout) were made in 1983 to study heritabilities of growth rate and other agronomic traits.

The experimental design was a nested split-split plot. Crosses were considered whole plots, families were sub-plots nested within crosses, and lines (4F 4 progeny lines and an F3 parent line) were sub-sub plots. Heritability estimates were calculated by the standard-unit and parent-offspring regression methods. Heritability values were adjusted for degree of inbreeding in both methods.

Heritabilities of growth rate at heading and growth rate at maturity were relatively low. Days to heading and maturity had moderate heritability values that are considered sufficient enough to expect good progress from selection in early generations of oat breeding programs. Phenotypic correlations for growth rate at maturity and dry matter at maturity with grain yield were highly significant. After adjusting for degree of inbreeding, the standard-unit method had higher heritability estimates than parent-offspring method. However, both methods showed similar trends in the estimation of heritabilities.