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A MODEL FOR FINDING THE RELATIVE WEIGHTS OF TRAITS USED IN SIMULTANEOUS MULTI-TRAIT SELECTION (PLANT BREEDING)
Abstract
When plant breeders must simultaneously select among genotypes on the basis of more than one trait, tradeoffs must be made so that all traits are improved to acceptable levels. Breeders usually have an intuitive feel for acceptable tradeoffs for a particular selection experiment, and when working with relatively few genotypes they can subjectively rank or order the selected genotypes in a manner that will reflect the intuitive tradeoffs. Since it has been difficult for breeders to numerically quantify their acceptable tradeoffs, or relative weights, the weights remain subjective in nature and as a result errors and inconsistencies occur when selections are made. A method has been developed which uses a breeder's subjective ranking of selected genotypes to quantify the breeder's intuitive relative weights. Using existing linear optimization techniques and computer programs, the method is simple to use. It is not dependent upon a consistent ranking by the breeder, and will point out where such inconsistencies exist. Appropriate corrections can then be made. Use of the procedure on data sets provided by two applied plant breeders resulted in relative weights, or trait coefficients, which were consistent with the general goals of the breeders. The derived coefficients represented quantification of the relative emphasis the two breeders were placing on the traits considered in the selection and ranking procedure, and thus provided a means of quantitatively comparing the selection goals and criteria of the two breeders. The derived coefficients can be used as the relative weights of a linear selection utility function. The selection function serves as a selection index and can be used to check for errors in the data set from which the original rankings were made, or it can be used in other selection experiments where the objectives and materials are consistent with the objectives and materials of the original experiment.
Subject Area
Agronomy
Recommended Citation
JOHNSON, BLAINE EARL, "A MODEL FOR FINDING THE RELATIVE WEIGHTS OF TRAITS USED IN SIMULTANEOUS MULTI-TRAIT SELECTION (PLANT BREEDING)" (1986). ETD collection for University of Nebraska-Lincoln. AAI8629534.
https://digitalcommons.unl.edu/dissertations/AAI8629534