IDENTIFICATION OF GIBBERELLINS IN LEAF TISSUES OF STRAWBERRY (FRAGARIA X ANANASSA-DUCH) GROWN UNDER DIFFERENT PHOTOPERIODS

In studies of the effect of long or short-day photoperiod treatments o n the qualitative gibberellin (GA) content of mature leaves of a facul tative short-day (SD) strawberry cultivar (Fragaria x ananassa Duch. c v. Elsanta), GA(1), GA(8), GA(17), GA(19), GA(20), GA(29) and GA(44) w ere identified by full-scan gas chromatography - mass spectrometry (GC -MS) in extracts from plants grown under long-day (LD) conditions, and GA(1), GA(5), GA(8), GA(19), GA(20) and GA(29) in similar extracts fr om plants subjected to eight SD cycles after growth under LD condition s. The early 13-hydroxylation GA biosynthetic pathway thus appeared to predominate, with the apparent absence of GA(5) in LD and of GA(17) a nd GA(44) in SD extracts providing evidence of modulation of this path way by photoperiod. A search, including GC-MS with selected ion monito ring, failed to detect GA(3), or the polyhydroxylated GA(85), GA(86), GA(87) or GA(32) for which some extracts were specifically purified.