Multi-donor × elite-based populations reveal QTL for low-lodging wheat

Abstract

Key message Low-lodging high-yielding wheat germplasm and SNP-tagged novel alleles for lodging were identified in a process that involved selecting donors through functional phenotyping for underlying traits with a designed phenotypic screen, and a crossing strategy involving multiple-donor × elite populations. Abstract Lodging is a barrier to achieving high yield in wheat. As part of a study investigating the potential to breed low-lodging high-yielding wheat, populations were developed crossing four low-lodging high-yielding donors selected based on lodging related traits, with three cultivars. Lodging was evaluated in single rows in an early generation and subsequently in plots in 2 years with contrasting lodging environment. A large number of lines lodged less than their recurrent parents, and some were also higher yielding. Heritability for lodging was high, but the genetic correlation between contrasting environments was intermediate-low. Lodging genotypic rankings in single rows did not correlate well with plots. Populations from the highest lodging background were genotyped (90 K iSelect BeadChip array). Fourteen markers on nine chromosomes were associated with lodging, differing under high- versus low-lodging conditions. Of the fourteen markers, ten were found to co-locate with previously identified QTL for lodging-related traits or at homoeologous locations for previously identified lodging-related QTL, while the remaining four markers (in chromosomes 2D, 4D, 7B and 7D) appear to map to novel QTL for lodging. Lines with more favourable markers lodged less, suggesting value in these markers as a selection tool. This study demonstrates that the combination of donor functional phenotyping, screen design and crossing strategy can help identify novel alleles in germplasm without requiring extensive bi-parental populations.

Genome-wide association mapping in elite winter wheat breeding for yield improvement

“…This gene was significant for improvement of the elite winter wheat lines investigated (QGY10, Table 6). Also, markers Ex_c3405_203 (6B: 0.9 Mbp) and Excalibur_rep_c102984_157 (2D: 641.1 Mbp) associated with the lodging score corresponded to QGY13 (6B: 4,9-9,1 Mbp) and QGY7 (2D: 633-635 Mbp) and explained 3.6% and 14.2% of variation, respectively (Dreccer et al 2022). Achieving optimal plant height is of prime importance for the stability, productivity and yield potential of the cultivars (Griffiths et al 2012).…”

“…The unpredictable occurrence of lodging has made it difficult for breeders to select for lodging tolerance. Ultimately, diagnostic genetic markers would be useful to improve standability in a breeding program (Dreccer et al 2022). In modern wheat cultivars, lodging risk has been reduced by introducing the semidwarfing genes Rht-B1b and Rht-D1b (Wilhelm et al 2013;Berry and Berry 2015).…”

“…Beside high-nitrogen fertilisation lodging can be caused by environmental factors, diseases or pests affecting stems or roots (Keller et al 1999). In wheat, stem characteristics such as material strength, based on lignin concentration and positioning and stem thickness plays a role (Berry et al 2007;Berry and Berry 2015;Dreccer et al 2020;Piñera-Chavez et al 2016;Dreccer et al 2022) and SNPs associated with lodging were identified (Dreccer et al 2022) Depending on the population analysed, GWAS analysis can identify different regions of the genome responsible for shaping a given trait (Yang et al 2021). By introducing varieties with very different yield potential into the analysed population, regions with major effects can be identified.…”

Localization of the quantitative trait loci related to lodging resistance in spring bread wheat (<i>Triticum aestivum</i> L.)

“…The classical genetic mapping have enabled one to detect both major and minor loci associated with lodging resistance in the most of the chromosomes of soft wheat such as 1B, 2A, 2D, 3A, 4A, 4B, 4D, 5A, 5B, 6A, 6B, 6D, 7B, 7D (Keller et al, 1999;Hai et al, 2005;Berry P.M., Berry S.T., 2015;Dreccer et al, 2022) as well as the markers located in the vicinity of the target locus. At the same time, it is noteworthy that the detected regions are quite extended due to the limited number of markers that were used while mapping (Börner et al, 2002;Verma et al, 2005).…”

Plant breeding for increased sustainability: challenges, opportunities and progress

“…Opportunities for combining superior productivity with low susceptibility to lodging through utilization of alleles already present in elite material are covered by Dreccer et al (2022). Rebetzke et al (2022), who explored seminal root length, root number and grain yield under drought stress in a wheat mapping population, present a novel and promising approach to breed future wheat cultivars with improved resistance to drought stress, a breeding target that will gain significance globally.…”