Identification of Gibberellins and 9,15-Cyclogibberellins in Developing Apple Seeds

Endogenous gibberellins (GAs) and GA-related compounds at two different developmental stages of apple seeds(Malus domestica cv. McIntosh) were analyzed by gas chromatography-mass spectrometry.From the seeds at ca. 10 and/or 14 weeks after full-bloom, the following GAs and 9,15-cyclogibberellins (9,15-cyclo-GAs) were identified by a comparison of their mass spectra and Kovats retention indices with those of authentic specimens: GA4, GA7, GA9, GA12, GA17, GA19, GA20, GA25, GA34, GA35, GA45,GA53, GA54, GA61, GA62, GA63, GA70, GA73, GA80, GA84, GA88, 3-epi-GA4, 3-epi-GA54, and 3-epi-GA63, 9,15-cyclo-GA9, lβ-hydroxy-9,15-cyclo-GA9, 2β-hydroxy-9,15-cyclo-GA9, 3α-hydroxy-9,15- cyclo-GA9, 3β-hydroxy-9,15-cyclo-GA9, and llβ-hydroxy-9,15-cyclo-GA9. The major components in the seeds at ca. 10 weeks after full-bloom were GA4, GA7, GA9, GA17, GA35, GA54, GA62, GA80, and GA84, and those in the seeds at ca. 14 weeks after full-bloom were GA17, GA25, GA45, GA62, GA63, GA80,GA84, 9,15-cyclo-GA9, and 1β-, 3β-, and 11β-hydroxy-9,15-cyclo-GA9. New GA number (GA103 _ 108) have been allocated to 9,15-cyclo-GA9, and 1β-, 2β-, 3β-, 3α-, and 11β-,hydroxy-9,15-cyclo-GA9, respectively (1β- and 3α-hydroxy-9,15-cyclo-GA9 were identified previously as fern anteridiogens, although GA numbers have not previously been assigned to these compounds). This is the first report of the co-occurrence of GA73 and 9,15-cyclo-GAs in higher plants.