Degree Type

Dissertation

Date of Award

1985

Degree Name

Doctor of Philosophy

Department

Agronomy

Abstract

A population of 179 random oat (Avena sativa L.) lines was tested in Iowa in natural environments with capacities to produce high, medium, and low grain yields. The data were used to evaluate the worth of these environments for selection for grain yield;The relative efficiencies of the productivity environments for selection were computed by using seven statistical approaches, some of them based on the grain yield (GYLD) genotypic values of the lines obtained from data collected in previous experiments;Nearly all statistical criteria indicated that success from selection was greater in the high productivity environment. Some criteria did not discriminate between high and medium productivity environments, but all criteria demonstrated that the low productivity environment was the least efficient for selection. The economic evaluation of the cost per unit of genetic gain indicated that the high productivity environment was the less expensive for selection;A critical evaluation of the methodologies used to assess the worth of the productivity environments for grain yield selection indicated that expected genetic gain, heritability percentage estimated from variance-component analysis, and differences between expected and actual gain from selection were rather inefficient statistics to evaluate environments for selection where the environments had marked differences in the productivity levels. The most effective one was actual genetic gain.

DOI

https://doi.org/10.31274/rtd-180813-8678

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Luis R. Barrales

Language

en

Proquest ID

AAI8604445

File Format

application/pdf

File Size

71 pages

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