Genome-Wide Association Reveals Trait Loci for Seed Glucosinolate Accumulation in Indian Mustard (Brassica juncea L.)

Abstract

Glucosinolates (GSLs) are sulphur- and nitrogen-containing secondary metabolites implicated in the fitness of Brassicaceae and appreciated for their pungency and health-conferring properties. In Indian mustard (Brassica juncea L.), GSL content and composition are seed-quality-determining traits affecting its economic value. Depending on the end use, i.e., condiment or oil, different GSL levels constitute breeding targets. The genetic control of GSL accumulation in Indian mustard, however, is poorly understood, and current knowledge of GSL biosynthesis and regulation is largely based on Arabidopsis thaliana. A genome-wide association study was carried out to dissect the genetic architecture of total GSL content and the content of two major GSLs, sinigrin and gluconapin, in a diverse panel of 158 Indian mustard lines, which broadly grouped into a South Asia cluster and outside-South-Asia cluster. Using 14,125 single-nucleotide polymorphisms (SNPs) as genotyping input, seven distinct significant associations were discovered for total GSL content, eight associations for sinigrin content and 19 for gluconapin. Close homologues of known GSL structural and regulatory genes were identified as candidate genes in proximity to peak SNPs. Our results provide a comprehensive map of the genetic control of GLS biosynthesis in Indian mustard, including priority targets for further investigation and molecular marker development.

Identification of Novel Loci Precisely Modulating Pre-Harvest Sprouting Resistance and Red Color Components of the Seed Coat in T. aestivum L.

“…We used gene prioritization with the aid of gene function, expression and metabolic networks' databases and tools to identify potential candidates that may play a role in controlling pre-harvest sprouting (PHS) and color traits. Such approaches became very useful to pinpoint candidate genes for further detailed bioinformatics and experimental analysis [54][55][56][57].…”

Developing multifunctional crops by engineering Brassicaceae glucosinolate pathways

“…Over the past few decades, a number of genes involved in GSL biosynthesis have been identified and characterized in the model plant Arabidopsis thaliana ( Harun et al., 2020 ) and subsequently in other Brassicaceae crop species, particularly in the genus Brassica ( Zhu et al., 2012 ; Augustine et al., 2013a ; Kim et al., 2013 ; Zhang et al., 2015a ; Seo et al., 2016 ; Sharma et al., 2016 ; Yin et al., 2017 ; Liu et al., 2020 ; Tandayu et al., 2022 ). Apart from biosynthesis of indole GSLs, de novo biosynthetic pathways of intact GSL molecules involve elongation of side chains, assembly of core structures, and secondary modification of side chains ( Figure 1 A).…”

Biopriming with Bacillus subtilis Enhanced the Sulphur Use Efficiency of Indian Mustard under Graded Levels of Sulphur Fertilization

“…Indian mustard (Brassica juncea) is the most commonly grown oilseed crop in India [28]. In the Brassica family, S is of great importance for proper vegetative growth and the biosynthesis of protein and oil [29].…”