title: QTL for root angle and number in a population developed from bread wheats (Triticum aestivum) with contrasting adaptation to water-limited environments.
abstract: Root architecture traits in wheat are important in deep soil moisture acquisition and may be used to improve adaptation to water-limited environments. The genetic architecture of two root traits, seminal root angle and seminal root number, were investigated using a doubled haploid population derived from SeriM82 and Hartog. Multiple novel quantitative trait loci (QTL) were identified, each one having a modest effect. For seminal root angle, four QTL (-log10(P) >3) were identified on 2A, 3D, 6A and 6B, and two suggestive QTL (-log10(P) >2) on 5D and 6B. For root number, two QTL were identified on 4A and 6A with four suggestive QTL on 1B, 3A, 3B and 4A. QTL for root angle and root number did not co-locate. Transgressive segregation was found for both traits. Known major height and phenology loci appear to have little effect on root angle and number. Presence or absence of the T1BL.1RS translocation did not significantly influence root angle. Broad sense heritability (h (2)) was estimated as 50 % for root angle and 31 % for root number. Root angle QTL were found to be segregating between wheat cultivars adapted to the target production region indicating potential to select for root angle in breeding programs.
authors.affiliation: University of Queensland, Queensland Alliance for Agriculture and Food Innovation (QAAFI), Leslie Research Facility, PO Box 2282, Toowoomba, QLD 4350, Australia. j.christopher@uq.edu.au
authors.forename: Jack
authors.initials: J
authors.lastname: Christopher
authors.forename: Mandy
authors.initials: M
authors.lastname: Christopher
authors.forename: Raeleen
authors.initials: R
authors.lastname: Jennings
authors.forename: Shirley
authors.initials: S
authors.lastname: Jones
authors.forename: Susan
authors.initials: S
authors.lastname: Fletcher
authors.forename: Andrew
authors.initials: A
authors.lastname: Borrell
authors.forename: Ahmad M
authors.initials: AM
authors.lastname: Manschadi
authors.forename: David
authors.initials: D
authors.lastname: Jordan
authors.forename: Emma
authors.initials: E
authors.lastname: Mace
authors.forename: Graeme
authors.initials: G
authors.lastname: Hammer
mesh_terms: D000220:Adaptation, Biological / Q000235:genetics*; D002874:Chromosome Mapping; D055864:Droughts; D005838:Genotype; D016014:Linear Models; D018517:Plant Roots / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development*; D040641:Quantitative Trait Loci / Q000235:genetics*; D014908:Triticum / Q000235:genetics*