Identification of endogenous gibberellins in inflorescence of Ornithogalumthyrsoides

Endogenous gibberellins (GAs) were extracted from inflorescence of Ornithog alum thyrsoides and identified by using combined gas-chromatography / mass spectrometry (GC/MS). Three 13-hydroxylated GAs, GA(19), GA(20) and GA(53), and thirteen 13-non-hydroxylated GAs, GA(4), GA(7), GA(9), GA(12), GA(15), GA(24), GA(25), GA(51), GA(61), GA(112), GA(115), 1, 2-didehydro GA(9) (wh ich is a novel GA, and has been assigned as GA(120)), and GA(120)-isolacton e were detected. The presence of these GAs suggests that both the early-13- hydroxylation GA biosynthesis pathway and the early-13-non-hydroxylated GA biosynthesis pathway were operating in the inflorescence of Ornithogalum. T he presence of GA(7), GA(8) and GA(120) suggests that GA(120) could be cons idered as a metabolic intermediate in the conversion of GA(9) into GA(7) in O. thyrsoides.