Dissecting the regulation of fructan metabolism in perennial ryegrass (Lolium perenne) with quantitative trait locus mapping

• Published in: The New phytologist 2006, Vol.169 (1), p.45-58
• Main Authors: Turner, L. B., Cairns, A. J., Armstead, I. P., Ashton, J., Skøt, K., Whittaker, D., Humphreys, M. O.
• Format: Article
• Language: English
• Subjects: Autumn; Biological and medical sciences; Biomarkers; carbohydrate content; carbohydrate metabolism; Carbohydrates - biosynthesis; Carbohydrates - chemistry; Chromosome Mapping; Chromosomes; fructan; Fructans; Fructans - metabolism; fructose; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant; Genetic loci; Genetic variation; Genome, Plant; Genotype; Genotypes; glucose; grasses; linkage (genetics); Lolium - genetics; Lolium - metabolism; Lolium perenne; Metabolism; Metabolism. Physicochemical requirements; perennial ryegrass; Phenotypic traits; plant genetics; Plant physiology and development; Plants; Quantitative Trait Loci; quantitative trait locus (QTL); Reproducibility of Results; sucrose; Tillers; water‐soluble carbohydrate (WSC)
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/j.1469-8137.2005.01575.x

• Quantitative trait locus (QTL) mapping, which can be a useful tool for dissecting complex traits, has been used here to study the regulation of fructan metabolism in temperate forage grasses. • An F2 mapping family, derived from a high water-soluble carbohydrate (WSC) x low WSC cross, was used to map fructans and the other components of WSC (sucrose, glucose and fructose) in leaves and tiller bases of perennial ryegrass (Lolium perenne) in spring and autumn. To characterize regions of the genome that control basic carbohydrate metabolism, a strategy to minimize the impact of genotype (G) x environment (E), and E-effects on the characterization of G-effects, was adopted. • Most traits were highly variable within the family. There was also considerable year-to-year environmental variation. However, significant genetic effects were detected, and several traits had high broad-sense heritability. QTL were identified on chromosomes 1, 2, 5 and 6. Leaf and tiller base QTL did not coincide. Individual QTL explained between 8 and 59% of the total phenotypic variation in the traits. • Fructan turnover, metabolism and their genetic control, and the effect of environment, are discussed in the context of the results.