Influence of Genotype on High Glucosinolate Synthesis Lines of <i>Brassica rapa</i>

• Main Authors: Prabhakaran Soundararajan, Sin-Gi Park, So Youn Won, Mi-Sun Moon, Hyun Woo Park, Kang-Mo Ku, Jung Sun Kim
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: International Journal of Molecular Sciences
• Subjects: biologically active compounds; glucosinolate synthesis; recombinant blocks; doubled haploid lines; isothiocyanates; cancer prevention
• Online Access: https://www.mdpi.com/1422-0067/22/14/7301

This study was conducted to investigate doubled haploid (DH) lines produced between high GSL (HGSL) <i>B</i><i>rassica rapa</i> ssp. <i>trilocularis</i> (yellow sarson) and low GSL (LGSL) <i>B. rapa</i> ssp. <i>chinensis</i> (pak choi) parents. In total, 161 DH lines were generated. GSL content of HGSL DH lines ranged from 44.12 to 57.04 μmol·g⁻¹·dry weight (dw), which is within the level of high GSL <i>B. rapa</i> ssp. <i>trilocularis</i> (47.46 to 59.56 μmol g⁻¹ dw). We resequenced five of the HGSL DH lines and three of the LGSL DH lines. Recombination blocks were formed between the parental and DH lines with 108,328 single-nucleotide polymorphisms in all chromosomes. In the measured GSL, gluconapin occurred as the major substrate in HGSL DH lines. Among the HGSL DH lines, BrYSP_DH005 had glucoraphanin levels approximately 12-fold higher than those of the HGSL mother plant. The hydrolysis capacity of GSL was analyzed in HGSL DH lines with a Korean pak choi cultivar as a control. Bioactive compounds, such as 3-butenyl isothiocyanate, 4-pentenyl isothiocyanate, 2-phenethyl isothiocyanate, and sulforaphane, were present in the HGSL DH lines at 3-fold to 6.3-fold higher levels compared to the commercial cultivar. The selected HGSL DH lines, resequencing data, and SNP identification were utilized for genome-assisted selection to develop elite GSL-enriched cultivars and the industrial production of potential anti-cancerous metabolites such as gluconapin and glucoraphanin.