title: Enhancing phosphorus uptake efficiency through QTL-based selection for root system architecture in maize.
abstract: Root system architecture (RSA) plays an important role in phosphorus (P) acquisition, but enhancing P use efficiency (PUE) in maize via genetic manipulation of RSA has not yet been reported. Here, using a maize recombinant inbred line (RIL) population, we investigated the genetic relationships between PUE and RSA, and developed P-efficient lines by selection of quantitative trait loci (QTLs) that coincide for both traits. In low-P (LP) fields, P uptake efficiency (PupE) was more closely correlated with PUE (r = 0.48-0.54), and RSA in hydroponics was significantly related to PupE (r = 0.25-0.30) but not to P utilization efficiency (PutE). QTL analysis detected a chromosome region where two QTLs for PUE, three for PupE and three for RSA were assigned into two QTL clusters, Cl-bin3.04a and Cl-bin3.04b. These QTLs had favorable effects from alleles derived from the large-rooted and high-PupE parent. Marker-assisted selection (MAS) identified nine advanced backcross-derived lines carrying Cl-bin3.04a or Cl-bin3.04b that displayed mean increases of 22%-26% in PUE in LP fields. Furthermore, a line L224 pyramiding Cl-bin3.04a and Cl-bin3.04b showed enhanced PupE, relying mainly on changes in root morphology, rather than root physiology, under both hydroponic and field conditions. These results highlight the physiological and genetic contributions of RSA to maize PupE, and provide a successful study case of developing P-efficient crops through QTL-based selection.
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Riliang
authors.initials: R
authors.lastname: Gu
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Fanjun
authors.initials: F
authors.lastname: Chen
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Lizhi
authors.initials: L
authors.lastname: Long
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Institute of Agricultural Resource and Environment, Jilin Academy of Agricultural Sciences, Changchun 130033, China.
authors.forename: Hongguang
authors.initials: H
authors.lastname: Cai
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Jiabo
authors.initials: J
authors.lastname: Yang
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Cereal Crops Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Wang
authors.affiliation: Cereal Crops Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China.
authors.forename: Huiyong
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Liu
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Guohua
authors.initials: G
authors.lastname: Mi
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
authors.forename: Fusuo
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Key Lab of Plant-Soil Interaction, MOE, Center for Resources, Environment and Food Security, College Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China. Electronic address: yuanlixing@cau.edu.cn.
authors.forename: Lixing
authors.initials: L
authors.lastname: Yuan
mesh_terms: D001692:Biological Transport / Q000235:genetics; D007178:Inbreeding; D010641:Phenotype; D010758:Phosphorus / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism*; D040641:Quantitative Trait Loci; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism*
chemical_list: D010758:Phosphorus
keywords: Maize; Marker-assisted selection; Phosphorus; Quantitative trait loci; Root system architecture