Graduate Thesis Or Dissertation
 

Estimation of genetic-parameters in the Oregon State University Hazelnut (Corylus avellana L.) breeding population

Pubblico Deposited

Contenuto scaricabile

Scarica il pdf
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/8336h460g

Descriptions

Attribute NameValues
Creator
Abstract
  • Heritability in the narrow sense and in the broad sense, variance components and correlation coefficients are important genetic parameters in a breeding program. The estimates of these parameters can provide important information for a breeder in the selection of parents, the most efficient design for evaluation of seedlings and advanced selections and the choice of selection strategy to improve many target traits simultaneously. In addition, histograms showing the distributions of the traits in offspring may provide additional information about parent combinations for the improvement of target traits. The Oregon State University hazelnut breeding program is developing improved varieties for the kernel market. Estimates of genetic parameters for most traits of interest are not available. Seventy seven trees representing 41 genotypes and 35 progenies were used to investigate midparent values and progeny means for 17 traits, including 13 kernel and nut traits, and 4 phenological traits, for three years. Estimates for heritability in the narrow sense are all high, ranging from 0.56 for amount of kernel fiber, and 0.58 for date of opening of female flowers to 0.87 for percent kernel, 0.88 for nut compression index and 0.89 for nut depth. Therefore, progeny means can be predicted from mid-parent values and response to selection is expected to be rapid for the improvement of all traits. The analysis of variance components revealed that genotypic variance accounted for most of the phenotypic variance. Although significant, the genotype X year interaction only accounted for a very small part of the phenotypic variance. It suggested one year's evaluation of genotypes for all traits should be sufficient except for nut weight, kernel weight, number of nuts per cluster, fiber amount, nut maturity, time of catkin elongation, and time of opening of female flowers. Genetic and phenotypic correlation coeficients were large and positive for nut size traits (nut length, width, depth, nut weight and kernel weight). Phenological traits (date of opening of female flowers, time of catkin elongation and time of leafing out) were also highly and positively correlated. But most other traits were uncorrelated with each other. Therefore, selection of parents with round nuts of medium size, high % kernel, easily-blanched kernels, and early nut maturity is expected to rapidly improve the population for all of these traits. Histograms show that all traits have continuous variation. Transgressive segregation is very common. For all traits except blanching ability, parent combinations may be based on midparent values. For the improvement of blanching ability, both parents should blanch easily. Because existing statistical packages do not allow easy calculation of genetic correlation coefficients for tree fruit and nut crops, the use of a spreadsheet to quickly estimate genetic correlation coefficients is demonstrated.
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
Dichiarazione dei diritti
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 256 Grayscale) using Scamax Scan+ V.1.0.32.10766 on a Scanmax 412CD by InoTec in PDF format. LuraDocument PDF Compressor V.5.8.71.50 used for pdf compression and textual OCR.
Replaces

Le relazioni

Parents:

This work has no parents.

In Collection:

Elementi

Thumbnail Titolo Data caricata Visibilità Azioni
file details YAOQIANG1999.pdf 2017-08-08 Pubblico Scaricare