Graduate Thesis Or Dissertation
 

Evaluation of three methods of selection in relation to yield and yield stability in winter wheat (Triticum aestivum Vill., Host)

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/c534fr460

Descriptions

Attribute NameValues
Creator
Abstract
  • The effectiveness of early generation selection for yield and yield stability and the possible identification of superior parental combinations were studied in winter wheat populations representing different levels of genetic diversity. Experimental material for evaluating yield stability consisted of nine bulk and seven modified bulk populations derived from nine parental combinations which represented the F₈, F₉, and F₁₀ generations. The F₉ and F₁₀ generations of nine bulk, nine modified bulk and two modified pedigree populations along with the respective parental populations were studied to determine the relationship of yield to genetic diversity. Linear regression of the mean yield of individual entries on the mean yield of all entries for each year was used to describe yield stability. Grain yield differences among populations and crosses were analyzed by a functional analysis of variance. The modified bulk populations were found to be superior to their respective parents in yield and to the bulk populations in yield and yield stability. The modified pedigree populations had the highest yield of all populations measured. It was concluded that populations with high genetic diversity not only do not produce the highest yield but may not provide the greatest stability of yield. Selection for grain yield in the F₄ generation was effective in identifying superior segregates. It was also possible to develop populations which had more yield stability. The highest yielding progeny were obtained from crosses between the medium yielding parents rather than between the highest yielding parents. This suggested that parental performance was of limited value in predicting the yielding ability of their resulting progeny. Therefore, selection for suitable parental combinations could not be based on their individual performance in the present study. It appeared that genetic factors for adaptability are as important as the level of genetic diversity in determining yield stability. A breeding system that allows the breeder to identify and incorporate genetic factors for adaptability and still maintain some genetic diversity in a new variety is suggested. Such a breeding system would prolong the length of time a variety could remain in commercial production and would allow such a variety to be grown over a more extensive range of environments.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome) using Capture Perfect 3.0.82 on a Canon DR-9080C in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items