Molecular mapping of seed aliphatic glucosinolates inBrassica juncea

Abstract

An RFLP genomic map with 316 loci was used to study the inheritance of aliphatic glucosinolates in Brassica juncea using doubled-haploid (DH) populations developed from a cross between RLM-514, an agronomically superior non-canola quality B. juncea (high erucic acid and high glucosinolates), and an agronomically poor canola quality B. juncea breeding line. Two QTLs (GSL-A2a and GSL-A2b) associated with 3-butenyl were consistent across years and locations, and explained 75% of the phenotypic variance in the population. Three QTLs (GSL-A2a, GSL-F, GSL-B3) affected 2-propenyl and explained 78% of the phenotypic variance in the population. For total aliphatic glucosinolates, five QTLs explained 30% to 45% of the total phenotypic variance in the population in different environments. Several QTLs (GSL-A7 and GSL-A3) were highly inconsistent in different environments. Major QTLs (GSL-A2a and GSL-A2b) associated with individual glucosinolates were non-significant for total aliphatic glucosinolates. A marker-assisted selection strategy based on QTLs associated with individual glucosinolates rather than total aliphatic glucosinolates is proposed for B. juncea.

Genetic analysis of agronomic and quality traits in mustard (Brassica juncea)

“…Loci on LG12 and LG14 may control the side-chain elongation step from propyl to butenyl, and loci on LG1 and LG6 may control the side-chain elongation step upstream propyl GSL. The results obtained were similar to those observed by Cheung et al (1998) and Mahmood et al (2003b) in B. juncea, and by Magrath et al (1994) in B. napus, where two duplicated genes originated from the two amphidiploid genomes.…”

“…This result tends to confirm the presence of at least two loci controlling these two GSLs. Love et al (1990), Cheung et al (1998) and Mahmood et al (2003b) had already showed the existence of these two loci and mapped two common QTLs for propenyl and butenyl GSLs in B. juncea. The allelic effects showed that high levels of SIN were associated with the alleles from BJ-99 at the QTL on LG12 and LG14 when they were associated with the alleles from BJ-70 at the QTL on LG6.…”

“…Cheung et al (1998), Lionneton et al (2002) and Mahmood et al (2003a) mapped QTLs associated with the fatty acid profile in B. juncea. QTLs controlling aliphatic GSLs in mustard were mapped by Cheung et al (1998) and more recently by Mahmood et al (2003b). However, few studies correlated quality traits with seed coat colour in mustard.…”

Molecular Genetics of Glucosinolate Biosynthesis in Brassicas: Genetic Manipulation and Application Aspects

“…Glucosinolate core structure and side chain modification pathway for 3C, 4C and 5C aliphatic glucosinolates. In the biosynthesis steps, gene symbols ending with A indicate A genome, C for C genome and At for A. thaliana Mithen et al, 1995;Mahmood et al, 2003). (Kliebenstein et al, 2001c;Parkin et al, 1994).…”

“…This QTL mapping study was carried out in a DH population derived from the F 1 of two B. juncea parental lines, J90-4317 (low glucosinolates) and J90-2733 (high glucosinolates). Mahmood et al, (2003) reported three QTL for 2-propenyl glucosinolate content which explained 78% of the phenotypic variance, while five QTL for total seed aliphatic glucosinolates explained phenotypic variance between 30% and 45%. In this study a DH population and an RFLP linkage map was used.…”