Table 1: Summary of tandem mass spectrometry parameters used for multiple reaction monitoring (MRM) for target compounds analyzed by LC-ESI-MS/MS. DP: declustering potential; FP: focusing potential; EP: entrance potential; CEP: collision cell entrance potential; CE : collision energy; CXP : collision exit potential.

Analyte	Q1	Q3	Dwell (ms)	DP	FP	EP	CE	CXP
Brassinolides (quantification)	481.4	445.5	100	40	185	10	14	15
Brassinolides (confirmation)	481.4	463.4	100	40	185	10	14	15
Castasterones (quantification)	465.5	429.3	100	46	194	9	23	14
Castasterones (confirmation)	465.5	447.4	100	46	194	9	23	14