Genetic analysis of provitamin A carotenoid β-cryptoxanthin concentration and relationship with other carotenoids in maize grain (Zea mays L.)

• Published in: Molecular breeding Vol. 37; no. 10; pp. 1 - 18
• Main Authors: Venado, Rafael E., Owens, Brenda F., Ortiz, Darwin, Lawson, Tyler, Mateos-Hernandez, Maria, Ferruzzi, Mario G., Rocheford, Torbert R.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2017; Springer Nature B.V
• Subjects: beta-carotene; beta-cryptoxanthin; Bioavailability; biofortification; Biomedical and Life Sciences; Biotechnology; Carotene; Carotenoids; Chromosome 5; chromosome mapping; Chromosomes; color; Conversion; Corn; crops; Gene loci; Gene mapping; genes; Genetic analysis; Genetic control; Genotype & phenotype; Grain; Human nutrition; humans; Hydroxylase; Life Sciences; Liquid chromatography; Lycopene; Mapping; Molecular biology; Nutrition; phenotype; Phenotypes; Plant biology; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; Quantitative trait loci; Vitamin A; Zea mays; Zeaxanthin; β-Carotene; Provitamin A; Visual score; Ratios; Carotenoids; β-Cryptoxanthin; Colorimeter; Quantitative trait loci (QTL)
• ISSN: 1380-3743; 1572-9788
• DOI: 10.1007/s11032-017-0723-8

Provitamin A (proVA) carotenoids are converted into retinol (vitamin A) in the human body, are the subject of human nutrition studies, and are targets for biofortification of staple crops. β-Carotene has been the principal target for enhancing levels of proVA. There is recent interest in enhancing the proVA carotenoid β-cryptoxanthin since it has excellent bioavailability, and in maize may be nearly as effective as β-carotene in providing retinol to humans. This study was designed to enhance our understanding of the genetic control of: levels of β-cryptoxanthin, conversion of β-carotene into β-cryptoxanthin and zeaxanthin, conversion of β-cryptoxanthin into zeaxanthin, and flux into and within the β-branch of carotenoid pathway. A biparental population derived from two inbreds with relatively high levels of β-cryptoxanthin and different ratios of β-carotene to β-cryptoxanthin and β-cryptoxanthin to zeaxanthin was studied. Three field replications of this F 2:3 population were grown, grain analyzed by liquid chromatography (LC), and composite interval mapping (CIM) performed to identify 90 quantitative trait loci (QTL) for carotenoids. We detected QTL for β-carotene/(β-cryptoxanthin + zeaxanthin) and (β-carotene + β-cryptoxanthin)/zeaxanthin ratios that contain candidate gene hydroxylase 4 ( hyd4 ), which has not been previously associated with QTL for carotenoids in maize grain. Two color assessment methods, visual score and chromameter reading, were used to phenotype one replicate of the population for initial assessment as simple alternative measuring procedures. A common finding for LC and chromameter analysis included QTL on chromosome 5 that contain candidate gene lycopene β cyclase ( lcyβ ).