Enhancing phosphorus uptake efficiency through QTL-based selection for root system architecture in maize. (20th November 2016)

• Record Type: Journal Article
• Authors: Gu, Riliang; Chen, Fanjun; Long, Lizhi; Cai, Hongguang; Liu, Zhigang; Yang, Jiabo; Wang, Lifeng; Li, Huiyong; Li, Junhui; Liu, Wenxin; Mi, Guohua; Zhang, Fusuo; Yuan, Lixing
• Is Part Of: Journal of genetics and genomics. Volume 43:Number 11(2016)
• Page Start: 663
• Page End: 672
• Publication Date: 2016-11-20
• Subjects: Maize -- Quantitative trait loci -- Phosphorus -- Root system architecture -- Marker-assisted selection; ABL advanced backcross line -- CRL crown root length -- CRN crown root number -- LP low phosphorus -- MAS marker-assisted selection -- NP normal phosphorus -- PRL primary root length -- PUE phosphorus use efficiency -- PupE phosphorus uptake efficiency -- PutE phosphorus utilization efficiency -- QTL quantitative trait locus -- RDW root dry weight -- RIL recombinant inbred line -- RLD root length density -- RSA root system architecture -- SRL seminal root length -- SRN seminal root number; Genetics -- Periodicals; Genomics -- Periodicals; 576.505
• DOI: 10.1016/j.jgg.2016.11.002
• Languages: English
• ISSNs: 1673-8527

Abstract

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.