Influence of environmental conditions on nutritional value of quality protein maize

Simple item page
dc.contributor.advisorLabuschagne, M. T.
dc.contributor.advisorVan Biljon, A.
dc.contributor.authorShawa, Hilda Chilekeni
dc.date.accessioned2019-07-02T05:37:42Z
dc.date.available2019-07-02T05:37:42Z
dc.date.issued2019-01
dc.description.abstractMaize is a staple crop to many people and it provides calorie, minerals and proteins to people in developing countries and globally. Quality protein maize (QPM) has improved nutritional quality but environmental conditions may have an effect on grain yield and nutritional content, especially under low nitrogen (N) conditions. The main objective of this study was to determine the influence of different production environments on nutritional quality and grain yield in QPM hybrids. This was done by grain yield assessment and nutritional quality analysis of QPM hybrids from CIMMYT-Zimbabwe, which were produced in different sites under low and optimum N conditions. The results for single analysis of variance (ANOVA) indicated that genotypes were significantly different for grain yield and all nutritional characteristics under low and optimum N. This was true except for oil content, phytic acid to iron molar ratio (MRFe) and phytic acid to zinc molar ratio (MRZn) at Harare (low N) and grain yield at Gwebi, phytic acid content, MRFe and MRZn at Glandel (optimum N). Combined ANOVA across optimum N locations were significantly different for genotypes, locations and genotype by environment interaction for all the traits, except for location effect for protein content. Negative correlations under both low and optimum environments were observed between α and γ zeins, β and γ zeins, and grain yield and Fe content. Principal component analysis biplots identified genotypes TH15938 and TH151082 to have high oil, phytic acid, γ zein and tryptophan contents in all environments. These characteristics were also positively correlated. Generally, low N reduced grain yield and nutritional quality characteristics. However, some specific genotypes were less sensitive to low N as it maintained grain yield (TH15976) and nutritional quality such as tryptophan (TH151082 and TH15895), oil (TH15938), total protein (Local check 1), Fe (TH15889) and Zn (Local check 1 and TH15851) contents. Alpha zein and phytic acid contents were reduced in most genotypes under low N conditions, suggesting increased tryptophan content, improved nutritional quality and micronutrient bioavailability under such conditions.en_ZA
dc.description.sponsorshipAgricultural Productivity Programme in Southern Africa (APPSA)en_ZA
dc.identifier.urihttp://hdl.handle.net/11660/9949
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA
dc.subjectQPMen_ZA
dc.subjectNon-QPMen_ZA
dc.subjectNutritional qualityen_ZA
dc.subjectMicronutrient bioavailabilityen_ZA
dc.subjectMicronutrient deficiencyen_ZA
dc.subjectGEIen_ZA
dc.subjectGenetic variationen_ZA
dc.subjectDissertation (M.Sc. (Plant Breeding))--University of the Free State, 2019en_ZA
dc.titleInfluence of environmental conditions on nutritional value of quality protein maizeen_ZA
dc.typeDissertationen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
ShawaHC.pdf
Size:
2.37 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.76 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
All Electronic Theses and Dissertations