Combining ability for crude protein in six selected inbred x Triticosecale genotype

Loading...
Thumbnail Image
Date
2007-12
Authors
Venter, Willem Daniel
Journal Title
Journal ISSN
Volume Title
Publisher
University of the Free State
Abstract
English: The objective of this study was to study the combining ability, heritability and additive genetic correlation of various crude protein characteristics in a selected fixed population. Three treatments were used to obtain grain production. The control treatment was left uncut; the cut 1 treatment had one cut of vegetative material before left for grain production while the cut (1+2) treatment had two consecutive cuts before the plants were allowed to produce grain. Characters measured for grain in all treatments were grain yield, percentage crude protein and crude protein yield. Characters measured for the vegetative material were percentage crude protein and crude protein yield. The total herbivore utilisable crude protein yield where the total crude protein yield of the vegetative material was combined with the grain crude protein yield of the cut (1+2) was also determined. Highly significant differences were shown between both genotypes and treatments for vegetative and grain characters when the phenotypic means of parents and offspring were evaluated in factorial analyses. The F1 progeny of a 6 x 6 half diallel cross were evaluated in the combining ability analyses using the Method 4, mixed model B analysis of Griffing (1956b), because only one reading per plot was obtainable for each of the characteristics measured. In the combining ability analyses of the F1 progeny, highly significant and significant differences were shown for gca effects and sca effects respectively when vegetative crude protein yield was evaluated in the cut 1 treatment. The σ2 gca/σ2 sca ratio differed between treatments and was higher for vegetative crude protein yield in the cut 1 treatment than in the cut (1+2) treatment. No significant differences between gca effects or sca effects could be found for grain yield or grain crude protein yield in the analyses of variance for any of the treatments. A significant difference between gca effects was shown for the combination character, total herbivore utilisable crude protein yield. With the aim of evaluating the combining ability effects to select parents for a better dual purpose triticale cultivar and to identify possible good hybrid combinations in mind, selections could be made with the available data of the cut 1 treatment as basis. When the variance components, heritabilities and correlated responses were calculated, the decision to base selection on the vegetative crude protein yield of the cut 1 treatment was confirmed. This character showed highly significant additive genetic correlations with both the total vegetative crude protein yield and the total herbivore utilisable crude protein yield.
Afrikaans: Die doel van hierdie studie was om die kombineervermoë, oorerflikhede en additiewe genetiese korrelasie van verskeie ruproteïen eienskappe in ‘n geselekteerde populasie te bepaal. Drie behandelings is gebruik om graanproduksie te bepaal. Die kontrole behandeling is nooit gesny nie; die een snysel behandeling is een keer gesny voordat dit gelos is om graan te produseer, terwyl die twee snysel behandeling twee agtereenvolgende snysels ontvang het voordat dit toegelaat is om graan te produseer. Graaneienskappe wat in al die behandelings bepaal is, is graanopbrengs, persentasie ruproteïen asook ruproteïenopbrengs. Eienskappe wat in die vegetatiewe material bepaal is, is ruproteïen, en ruproteïenopbrengs. Die totale herkouer toeganklike ruproteïenopbrengs, wat ‘n kombinasie is van die totale ruproteïenopbrengs van die vegetatiewe materiaal en die graan ruproteïenopbrengs van die ooreenstemmende behandeling, is ook bepaal. Daar was hoogs betekenisvolle verskille tussen genotipes asook behandelings met die ontleding van die fenotipiese gemiddeldes van beide ouers en nageslag d.m.v. faktoriaal analise. Die F1 nageslag van ‘n 6 x 6 halfdialleel kruising is d.m.v. Metode 4, gemengde model B van Griffing (1956b) vir kombineervermoë ontleed, omdat daar slegs een waarde per perseel vir elke eienskap beskikbaar was. By die ontleding van kombineervermoë vir vegetatiewe ruproteïenproduksie in die F1 nageslag, is hoogs betekenisvolle en betekenisvolle verskille t.o.v. algemene kombineervermoë effekte en spesifieke kombineervermoë effekte onderskeidelik, in die een snysel behandeling verkry. Die verhouding tussen die variansie van die algemene kombineervermoë tot die variansie van die spesifieke kombineervermoë, het tussen behandelings verskil en was hoër vir vegetatiewe ruproteïen opbrengs in die een snysel behandeling as in die twee snysel behandeling. Geen betekenisvolle verskille kon t.o.v. algemene kombineervermoë effekte en spesifieke kombineervermoë effekte in enige van die behandelings vir graanopbrengs of graan ruproteïenopbrengs gevind word nie. Betekenisvolle verskille tussen algemene kombineervermoë effekte is t.o.v. die kombinasie eienskap, totale herkouer toeganklike ruproteïenopbrengs, verkry. Waar die doel was om die kombineervermoë effekte so te evalueer ten einde ouers vir ‘n beter dubbeldoel triticale kultivar te selekteer en ook goeie baster kombinasies te identifiseer, kon seleksies met die beskikbare data vanaf die een snysel behandeling gedoen word. Die geldigheid van die besluit om seleksie op die vegetatiewe ruproteïenopbrengs van die een snysel behandeling te grond, is bevestig toe die variansiekomponente, oorerflikhede en gekorreleerde respons bepaal is. Hierdie eienskap het hoogs betekenisvolle additiewe genetiese korrelasies getoon met die totale vegetatiewe ruproteïenopbrengs asook die totale herkouer toeganklike ruproteïenopbrengs.
Description
Keywords
Diallel, Fixed, Vegetative, Protein, Grain, Yield, Combining, Heritability, Correlation, Triticale -- Breeding, Triticale -- Genetics, Plant proteins, Triticale
Citation