Investigation into the suitability of wheat for ethanol production in the Western Cape

Dix, Rodger (2010-12)

Thesis (MScAgric (Genetics))--University of Stellenbosch, 2010.

Includes bibliography.

Thesis

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.

Please refer to this item in SUNScholar by using the following persistent URL: http://hdl.handle.net/10019.1/5419
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