QTL meta-analysis of root traits in Brassica napus under contrasting phosphorus supply in two growth systems

Abstract

A high-density SNP-based genetic linkage map was constructed and integrated with a previous map in the Tapidor x Ningyou7 (TNDH) Brassica napus population, giving a new map with a total of 2041 molecular markers and an average marker density which increased from 0.39 to 0.97 (0.82 SNP bin) per cM. Root and shoot traits were screened under low and ‘normal’ phosphate (Pi) supply using a ‘pouch and wick’ system, and had been screened previously in an agar based system. The P-efficient parent Ningyou7 had a shorter primary root length (PRL), greater lateral root density (LRD) and a greater shoot biomass than the P-inefficient parent Tapidor under both treatments and growth systems. Quantitative trait loci (QTL) analysis identified a total of 131 QTL, and QTL meta-analysis found four integrated QTL across the growth systems. Integration reduced the confidence interval by ~41%. QTL for root and shoot biomass were co-located on chromosome A3 and for lateral root emergence were co-located on chromosomes A4/C4 and C8/C9. There was a major QTL for LRD on chromosome C9 explaining ~18% of the phenotypic variation. QTL underlying an increased LRD may be a useful breeding target for P uptake efficiency in Brassica.

Corn Yield and Phosphorus Use Efficiency Response to Phosphorus Rates Associated With Plant Growth Promoting Bacteria

“…In addition, P is responsible for the storage and transport of energy for endergonic processes, such as the synthesis of organic compounds and the active uptake of nutrients (Marschner, 2012). Also, P is related to root system development and plant growth (Sulieman and Tran, 2015;Fink et al, 2016;Zhang et al, 2016). There are several studies reporting the P fertilization benefits in corn crop (Wen et al, 2016;Li et al, 2017;Schlegel and Havlin, 2017;Ortas and Islam, 2018;Preston et al, 2019).…”

“…However, plant nutritional demand is limited as verified by the linear decreasing response in PUE to P 2 O 5 application rates, regardless of PGPB inoculation. In addition, almost 80% of P content in soil can be fixed in forms unavailable to plants (White and Hammond, 2008;Zhang et al, 2016). Therefore, P application must be rational and optimized, since the increased P 2 O 5 application rates results in increased losses and less utilization by cropping systems.…”

Breeding histories and selection criteria for oilseed rape in Europe and China identified by genome wide pedigree dissection

“…Agronomic and seed traits within the pedigrees of both these cultivars have undergone substantial improvement through extensive breeding efforts. These cultivars were crossed to generate the Bna TNDH biparental doubled haploid segregating population, which has been used extensively to understand the genetic basis of many agronomic and economically important traits in B. napus 1 , 13 , 14 , 16 , 17 , 19 , 23 , 33 – 36 . Uncovering the associated underlying patterns of allelic variation in the context of the sequenced genome is anticipated to provide valuable knowledge that will guide subsequent advances in breeding 1 , 11 .…”

Genome‐wide selection footprints and deleterious variations in young Asian allotetraploid rapeseed

“…A double haploid (DH) population (BnaTNDH) with 353 DH lines derived from crossing NY7 with a European winter cultivar Tapidor was used to construct the genetic map. This population has been used as a reference genetic mapping population internationally and has accumulated much genotypic and phenotypic data (Qiu et al, 2006;Zhang et al, 2016). The 353 DH lines were genotyped using the Illumina Infinium Brassica 60K SNP array.…”