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.

Association Mapping of Root Traits for Drought Tolerance in Bread Wheat

“…The MTA located on chromosome 7B recognized by Xgwm 302 and that of 6D was identiied by Xwmc 749 as in Figure 7. The results are consistent with previous results where QTL for RA was located on chromosome 7B at 86cM, and reported four QTLs for RA was located on chromosome 2A, 3D, 6A and 6D [47,48].…”

A comparative study of root system architecture in seedlings ofBrachypodium spp.using three plant growth supports

“…The root system is one of the main factors influencing yield, since the capture of water and nutrients, and the support and anchorage of the stems, all depend on the roots. The degree of development of the roots and the RSA can vary widely depending on the species, the genotype and the availability of water and nutrients (Forde and Lorenzo 2001;Manschadi et al 2008;Ingram et al 2012;Christopher et al 2013;Obara et al 2014;Tyagi et al 2014), but its study is difficult since the roots grow underground and are hidden from direct observation. However, laboratory procedures of visualizing the RSA exists.…”

“…al. 1997;Ren et al 2012;Christopher et al 2013;Canè et al 2014). Marker-assisted selection (MAS) has also been used to introduce QTL that control different RSA characteristics in some rice varieties into the genomes of other rice varieties (Steele et al 2006(Steele et al , 2013.…”

Genomics Approaches to Dissect the Genetic Basis of Drought Resistance in Durum Wheat

“…Roots show a high level of morphological and developmental plasticity, a peculiarity that allows plants to adapt to moisture-limited conditions (de Dorlodot et al 2007 ;Den Herder et al 2010 ). An example is provided by root aerenchyma and root angle, root features that are receiving increasing attention for their effects on the response to drought and other abiotic stresses (Christopher et al 2013 ). Other root features remain much more challenging to investigate, particularly under fi eld conditions, such as in the case of root depth, a trait that has repeatedly shown a key role in crop adaptation to drought conditions when residual moisture at maturity is mainly available in deeper soil layers (Blum 2009(Blum , 2011Watt et al 2013 ).…”