KRISHI
ICAR RESEARCH DATA REPOSITORY FOR KNOWLEDGE MANAGEMENT
(An Institutional Publication and Data Inventory Repository)
"Not Available": Please do not remove the default option "Not Available" for the fields where metadata information is not available
"1001-01-01": Date not available or not applicable for filling metadata infromation
"1001-01-01": Date not available or not applicable for filling metadata infromation
Please use this identifier to cite or link to this item:
http://krishi.icar.gov.in/jspui/handle/123456789/47428
Title: | Statistical Techniques for Triallel and Tetra-allele Cross Experiments |
Other Titles: | Not Available |
Authors: | Mohd Harun |
ICAR Data Use Licennce: | http://krishi.icar.gov.in/PDF/ICAR_Data_Use_Licence.pdf |
Author's Affiliated institute: | ICAR::Indian Agricultural Statistics Research Institute |
Published/ Complete Date: | 2020-10-21 |
Project Code: | Not Available |
Keywords: | partial triallel crosses orthogonal tetra-allele cross designs Best Linear Unbiased Predictor |
Publisher: | Not Available |
Citation: | Not Available |
Series/Report no.: | Not Available; |
Abstract/Description: | The major objective of a breeding programme is to release new hybrids with enhanced genetic potential, which is based on information on general and specific combining abilities, information related to variance components and predictor of yielding capacities of crosses. Further, designs used for attaining these goals should be robust against disturbances like missing observation. Higher order crosses like triallel and tetra-allele crosses are considered as they, being genetically more viable and consistent performers, can provide more information on combining abilities. Under a fixed effects model including specific combining abilities, the estimates of combining abilities have been obtained for both triallel and tetra-allele crosses. A method of construction of partial triallel crosses arranged in blocks has been obtained based on two-associate triangular association scheme alongwith the information matrices, eigenvalues, variance factors, efficiency factor and degree of fractionation. Another two methods of constructing partial triallel cross designs have also been obtained using various types of Lattice designs and Kronecker product of incidence matrices respectively. All these methods are efficient alongwith lower degree of fractionation. A class of orthogonal tetra-allele cross designs for estimating contrasts pertaining to general combining ability effects has been obtained under a reduced model including lower order specific combining ability effects using mutually orthogonal Latin squares. The obtained class satisfies the condition of optimality for eqiureplicated designs for tetra-allele crosses and are having low degree of fractionation. Also, under a random effect model excluding specific combining ability effects for tetra-allele crosses, the Best Linear Unbiased Predictor (BLUP) for yielding capacity of cross has been obtained. A lower bound to mean square prediction error for characterizing optimal class of designs has been obtained. The lower bound so obtained is important in finding optimal designs. The unbiased estimates of variance components alongwith sampling distribution have been obtained following Henderson Method III. These parameters can be further used for obtaining the estimates of genetic parameters. The robustness of designs against missing observation using connectedness and efficiency criteria has been studied and a list of efficient robust designs for triallel and tetra-allele crosses has been tabulated. A list of robust and efficient designs with lower degree of fractionation is very much helpful for the breeders in situations of missing observation. Programs have been written in SAS [PROC IML] software for computing efficiency factor of the designs involving triallel crosses for estimating gca effects to investigate the robustness of designs against missing observation by calculating the canonical efficiency. |
Description: | Not Available |
ISSN: | Not Available |
Type(s) of content: | Dissertation/Thesis |
Sponsors: | Not Available |
Language: | English |
Name of Journal: | Not Available |
NAAS Rating: | Not Available |
Volume No.: | Not Available |
Page Number: | Not Available |
Name of the Division/Regional Station: | Not Available |
Source, DOI or any other URL: | Not Available |
URI: | http://krishi.icar.gov.in/jspui/handle/123456789/47428 |
Appears in Collections: | AEdu-IASRI-Publication |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
Thesis_Harun-10412.pdf | 5.3 MB | Adobe PDF | View/Open |
Items in KRISHI are protected by copyright, with all rights reserved, unless otherwise indicated.