title: Comprehensive phenotypic analysis and quantitative trait locus identification for grain mineral concentration, content, and yield in maize (Zea mays L.).
abstract: Understanding the correlations of seven minerals for concentration, content and yield in maize grain, and exploring their genetic basis will help breeders to develop high grain quality maize. Biofortification by enhanced mineral accumulation in grain through genetic improvement is an efficient way to solve global nutrient malnutrition, in which one key step is to detect the underlying quantitative trait loci (QTL). Herein, a maize recombinant inbred population (RIL) was field grown to maturity across four environments (two locations × two years). Phenotypic data for grain mineral concentration, content and yield were determined for copper (Cu), iron (Fe), manganese (Mn), zinc (Zn), magnesium (Mg), potassium (K) and phosphorus (P). Significant effects of genotype, location and year were observed for all investigated traits. The strongest location effects were found for Zn accumulation traits probably due to distinct soil Zn availabilities across locations. Heritability (H (2)) of different traits varied with higher H (2) (72-85 %) for mineral concentration and content, and lower (48-63 %) for mineral yield. Significant positive correlations for grain concentration were revealed between several minerals. QTL analysis revealed 28, 25, and 12 QTL for mineral concentration, content and yield, respectively; and identified 8 stable QTL across at least two environments. All these QTL were assigned into 12 distinct QTL clusters. A cluster at chromosome Bin 6.07/6.08 contained 6 QTL for kernel weight, mineral concentration (Mg) and content (Zn, K, Mg, P). Another cluster at Bin 4.05/4.06 contained a stable QTL for Mn concentration, which were previously identified in other maize and rice RIL populations. These results highlighted the phenotypic and genetic performance of grain mineral accumulation, and revealed two promising chromosomal regions for genetic improvement of grain biofortification in maize.
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Riliang
authors.initials: R
authors.lastname: Gu
authors.forename: Fanjun
authors.initials: F
authors.lastname: Chen
authors.forename: Bingran
authors.initials: B
authors.lastname: Liu
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.forename: Jianchao
authors.initials: J
authors.lastname: Liu
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Li
authors.forename: Qingchun
authors.initials: Q
authors.lastname: Pan
authors.forename: Jordon
authors.initials: J
authors.lastname: Pace
authors.forename: Ayaz-Ali
authors.initials: AA
authors.lastname: Soomro
authors.forename: Thomas
authors.initials: T
authors.lastname: Lübberstedt
authors.forename: Guohua
authors.initials: G
authors.lastname: Mi
authors.forename: Lixing
authors.initials: L
authors.lastname: Yuan
mesh_terms: D003300:Copper / Q000737:chemistry; D002523:Edible Grain / Q000737:chemistry / Q000235:genetics; D007501:Iron / Q000737:chemistry; D008274:Magnesium / Q000737:chemistry; D008345:Manganese / Q000737:chemistry; D008903:Minerals / Q000737:chemistry*; D010641:Phenotype; D010758:Phosphorus / Q000737:chemistry; D000069600:Plant Breeding; D011188:Potassium / Q000737:chemistry; D040641:Quantitative Trait Loci; D012639:Seeds / Q000737:chemistry*; D003313:Zea mays / Q000235:genetics*; D015032:Zinc / Q000737:chemistry
chemical_list: D008903:Minerals; D010758:Phosphorus; D008345:Manganese; D003300:Copper; D007501:Iron; D008274:Magnesium; D015032:Zinc; D011188:Potassium