Characterization of Radish Germplasm by Phenotypic Traits and Glucosinolate Composition

This study evaluated glucosinolate (GSL) composition and phenotypic traits in 72 radish (Raphanus sativus L. var. sativus) accessions, including 69 germplasm and 3 cultivars. Seven GSLs: glucoraphanin, glucoraphenin, glucoerucin, glucoraphasatin, glucobrassicin, glucobarbarin, and glucoberteroin were quantified using UPLC (mg/kg DW). Under the evaluated conditions, accession 10 (IT203308, Russia) showed high glucobarbarin (3976.9), while 38 (IT262009, Germany) and 39 (IT262067, North Korea) accumulated glucoraphasatin above 3500. Accession 40 (IT262091, North Korea) exhibited the highest glucoraphenin (612.9), and glucoerucin was enriched in 12 (IT204244, Israel), 19 (IT215036, Republic of Korea), and 35 (IT261962, Russia). Principal component analysis identified outliers: 10 (IT203308, Russia), 12 (IT204244, Israel), 19 (IT215036, Republic of Korea), 35 (IT261962, Russia), 38 (IT262009, Germany), 40 (IT262091, North Korea), 34 (IT261948, Kyrgyzstan), and 59 (IT306725, Malaysia), separated from central accessions. Multivariate analyses indicated that GSL accumulation and phenotypic variation were not consistently associated. These findings identify high-GSL and PCA-defined outlier accessions as potential donor resources for the breeding of radish with improved glucosinolate-related nutritional quality, while demonstrating that glucosinolate profiles cannot be reliably predicted from external phenotypes.