Detection of QTL for six yield-related traits in oilseed rape (Brassica napus) using DH and immortalized F2 populations

Abstract

The inheritance of yield-related traits in rapeseed (Brassica napus) is poorly understood, and the investigations on mapping of quantitative trait loci (QTL) for such traits are only few. QTL related to six traits were mapped which include plant height (PH), height of lowest primary effective branch (HPB), length of main inflorescence (LMI), silique length (SL), number of primary branches (FB) and silique density (SD). A set of 258 doubled haploid (DH) lines derivatives of a cross between a canola variety Quantum and a resynthesized B. napus line No.2127-17, and a fixed immortalized F(2) (designated as IF(2)) population generated by randomly permutated intermating of these DHs were investigated. A genetic linkage map was constructed using 208 SSR and 189 SRAP markers for the DH population. Phenotypic data were collected from three environments for the two populations. Using composite interval mapping analyses, 30 and 22 significant QTL were repeatedly detected across environments for the six traits in the DH and IF(2) populations, respectively. Twenty-nine QTL were common between the two populations. The directions of parental contribution for all common QTL were the same, showing a great potential for marker-assisted selection in improving these traits. Some chromosomal regions harbor QTL for multiple traits, which were consistent with significant phenotypic correlations observed among traits. The results provided a better understanding of the genetic factors controlling yield-related traits in rapeseed.

In silico integration of quantitative trait loci for seed yield and yield-related traits in Brassica napus

“…For B. napus, many studies report QTL mapping of seed yield and related yield traits, including traits such as seed weight, pod number, seed number per pod, anthesis, and others (Basunanda et al 2010;Chen et al 2007;Fan et al 2010;Long et al 2011;Shi et al 2009;Zhang et al 2012). Due to this available body of research, it is possible to summarize and compare QTL maps for seed yield and the yield-related traits in B. napus, advancing QTL mapping research.…”

“…QTLs for seed yield and yield-related traits in B. napus were collected from 15 articles published over the last 20 years (Butruille et al 1999;Quijada et al 2006;Udall et al 2006;Zhao et al 2005;Chen et al 2007;Shi et al 2009;Fan et al 2010;Wang and Guan 2010;Radoev et al 2008;Basunanda et al 2010;Shi et al 2011;Zhang et al 2011;Würschum et al 2012;Zhang et al 2012;Yang et al 2012b). The collected information included traits, species, QTL-linked markers, name of the main QTL, linkage group, logarithm of odds (LOD) value, confidence interval, proportion of the phenotypic variation explained by the QTL, additive effect, dominance effect, peak position, reference, first author, and published time (as shown in Supplementary Table 1).…”

“…The collected information included traits, species, QTL-linked markers, name of the main QTL, linkage group, logarithm of odds (LOD) value, confidence interval, proportion of the phenotypic variation explained by the QTL, additive effect, dominance effect, peak position, reference, first author, and published time (as shown in Supplementary Table 1). Traits comprised biomass yield (BY) (kg/ha), flowering time (FT) (days), maturity time (MT) (days), number of primary branches (NPB), plant height (PH) (cm), pod yield/100 pods (PY) (g), silique density number/cm (SD), silique length (SL) (cm), siliques per plant (SPP), seeds per silique (SPS), seed yield (SY) (kg/ha), thousand seed weight (TSW) (g) and test weight (TW) (kg/L), which are described in detail in the following references: Chen et al 2007;Shi et al 2009;Basunanda et al 2010;Shi et al 2011). …”

“…B. napus (canola or rapeseed) is planted worldwide, and is an essential source of oil, fodder and biodiesel. Since the first molecular linkage map in B. napus was reported (Landry et al 1991), thousands of important QTLs for traits such as seed yield, yield components, biomass, flowering time, seed quality, disease resistance or tolerance, mineral nutrition and other yield-related traits have been identified in B. napus (Basunanda et al 2010;Cai et al 2012;Chen et al 2007;Fan et al 2010;Feng et al 2012;Long et al 2007;Rygulla et al 2008;Yang et al 2011;Shi et al 2013;Raman et al 2013). However, to date, it is still very difficult for Brassica breeders to effectively utilize this large body of QTL data.…”

Effect of regeneration procedures on the genetic integrity of Brassica oleracea accessions

“…napus (Chen et al 2007). Allele Ni2C12-4 in population MBG-BRS0072 was also under the action of directional selection.…”