Thesis (MScAgric (Genetics))--University of Stellenbosch, 2010. / Includes bibliography. / ENGLISH ABSTRACT: This study aimed to investigate the suitability of spring wheat in the Western Cape as a potential
feedstock for a future bio-ethanol industry as well as initiate a pre-breeding effort to develop bioethanol
-directed improved lines.
Determined primarily on grain yield, disease resistance and, direct as well as indirect
assaying of important parameters, material was selected from a base-population for use as male
parents. These were crossed with female parents sourced from the Stellenbosch University Plant
Breeding Laboratory (SU-PBL) male sterility -mediated marker-assisted recurrent selection (MSMARS)
programe. This programe is constituted by an agronomically and disease-resistance -
improved population, containing a dominant male sterility gene (Ms3). The progeny of these
crosses was used to initiate the production of doubled haploids in order to ultimately derive higher
ethanol yielding lines.
Multi-location field trial (MLFT) data revealed that 00K60-16-3-3 was the best adapted and
highest yielding (2160.95 litres ethanol per hectare) advanced breeding line (ABL). Its performance
was not statistically significantly less than first-ranked 03H86-8-2 (2184.62 litres per hectare) and
both ABLs significantly (P≤0.05) out-performed six controls in the study. ABL 00K60-16-3-3 was
also the most adapted in terms of potential yield in litres per ton of grain. ABL 03H86-8-1 was
second recommended for the Western Cape, performing above the expected mean for yield in
litres per hectare. Further adaptation of specific ABLs to the two major sub-regions of the Western
Cape i.e. the Swartland and Southern Cape including the Rûens was also elucidated. Napier was
significantly the highest yielding trial site although none of the considered sites were both stable
and high yielding. It was also determined that entry X locality interaction (GxE) was indeed
significant across the whole production area regarding litres per hectare as well as its two subregions.
This is expected considering the environmentally diverse nature of the region as a whole.
Using several entries as examples, relationships between starch, ethanol production in
litres ethanol per hectare and litres per ton where grain yield is not taken into consideration were
illustrated. Overall applicable relationships other than clear grouped entry differences could not be
established. What was clearly demonstrated however, is that the maximization of grain yield is
paramount. Highlighted thus, is the individuality of a specific genotype where MLFTs will always
be required to quantify genotype potential. / AFRIKAANSE OPSOMMING: Die studie het ten doel gehad om die geskiktheid van lentekoring vir die produksie van bio-etanol in
die Wes Kaap te evalueer. Ook het dit ‘n voortelingsprogram geinisieer vir die teel van lyne met
verhoogde bio-etanol opbrengs.
Materiaal vir gebruik as manlike ouers in ‘n basis-populasie is geselekteer gegrond
grootliks op graanopbrengs, siekteweerstand en direkte sowel as indirekte etanolopbrengs
kenmerke. Die gekose materiaal is gekruis met vroulike ouers verkry vanaf Stellenbosch
Universiteit se Planteteeltlaboratorium (SU-PTL) se manlike steriliteits gedrewe merker bemiddelde
herhalende seleksieprogram. Die program is saamgestel uit ‘n verbeterde populasie ten opsigte
van siekteweerstand en agronomiese eienskappe. Dit bevat ook ‘n dominante steriliteitsgeen. Die
nageslag van die kruisings is aangewend vir die inisiasie van die produksie van verdubbelde
haploied lyne vir die verkryging van lyne met verhoogde etanol opbrangs.
Die ontleding van data ten opsigte van die multi-lokaliteitsproewe (MLP) het aangetoon
dat gevorderde teellyn (GTL) 00K60-16-3-3 die beste aangepas was en ook die hoogste opbrengs
(2160.95 liters etanol per hektaar) gegee het. 00K60-16-3-3 was ook nie statisties betekenisvol
swakker as die eerste geplaaste 03H86-8-2 (2184.62 liters etanol per hektaar) en beide GTLs was
statisties betekenisvol beter (P≤0.05) as die ses kontroles in die studie. GTL 00K60-16-3-3 was
ook die beste aangepaste in terme van etanol opbrengs in liters per ton graan. GTL 03H86-8-1
was tweede aanbevole vir die Wes-Kaap met ‘n prestasie bo die verwagte gemiddelde opbrengs in
liters per hektaar. Verdere aanpassing van spesifieke GTLs vir die twee mega-omgewings in Wes-
Kaap nl. Swartland en Suid-Kaap insluitend die Rûens was ook afgelei. Napier was betekenisvol
beter, maar nie enige van die lokaliteite was beide stabiel en hoë opbrengs lokaliteite nie. Dit was
ook bepaal dat die inskrywing by lokaliteits interaksie (GXE) betekenisvol was oor die hele
produksiegebied ten opsigte van liters per hektaar asook in die twee mega-omgewings afsonderlik.
Dit was egter te verwagte gegewe die diverse aard van die omgewings in die streek as geheel.
Deur gebruik te maak van verskeie inskrywings as voorbeelde is die verwantskap tussen
stysel, etanol produksie in liters etanol per hektaar en liters etanol per ton graan geillustreer sonder
om graanopbrengs in ag te neem. Oorhoofs toepaslike verwantskappe anders as duidelike
gegroepeerde inskrywings verskille kon nie afgelei word nie. Wat wel duidelik gedemonstreer kon
word is dat maksimum graanopbrengs uiters belangrik was. Dit is dus duidelik dat weens die
wisselende aard van spesifieke genotipes MLPs altyd van kardinale belang sal wees vir die
kwantifisering van ‘n genotipe se potensiaal.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/5419 |
| Date | 12 1900 |
| Creators | Dix, Rodger |
| Contributors | Botes, W. C., University of Stellenbosch. Faculty of Agrisciences. Dept. of Genetics. |
| Publisher | Stellenbosch : University of Stellenbosch |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 107 p. : ill. |
| Rights | University of Stellenbosch |
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