2.2.3. The genus Rorippa

The genus had been investigated in detail earlier (Olsen et al., 2016), except seeds of R. sylvestris . Here, the seeds were investigated with the aim to search for seed-specific acylated GSL (Table 5). Green parts and flowers of the sampled individual matched the previously reported profiles (results not shown). The GSL profile of the seeds was dominated by 6homoMet-derived 8mSOo (69) and the corresponding methylthio precursor 8mSo (92), i.e. the “C8” chain length group corresponding to six rounds of chain elongation in the early biosynthesis, in agreement with the previously reported leaf and root profiles. From visual comparison of chain-length distributions in the common table (Table 5), the distribution in R. sylvestris was obviously more narrow than seen for Nasturtium and Planodes, suggesting a more stringent, processive chain elongation system (Textor et al., 2007; Kumar et al., 2019; Petersen et al., 2019). Acylated GSLs, BCAA-derived, Trp-derived or Phe-derived GSLs were not detected (Table 4, Table 5) but Trp-derived GSLs are confirmed in other organs of the same species (Olsen et al., 2016).