Examination of glucoraphanin content in broccoli seedlings over growth and the impact of hormones and sulfur-containing compounds

In this study, we found that the glucoraphanin (GR) content in broccoli seedlings decreased before first foliage leaf emergence. Methyl jasmonate (MeJA) treatment significantly increased the GR content in broccoli, with effects being consistent over the period of application. Unlike MeJA, abscisic acid (ABA) and salicylic acid (SA) led to slight GR accumulation within 24 h of the application. The feeding of a sulfur-containing compound, MgSO 4 , via the root of broccoli caused accumulation of GR within 24 h. Thus, both the germination time and the duration of sulfur fertilization and MeJA application are important to maximize GR content in broccoli.