The growth-promoting activity of two C20gibberellins, gibberellins A24and A25, was determined in five bioassay systems and compared with that of gibberellic acid in four of the bioassays and with gibberellin A4in the other. Gibberellin A24was highly active in the oat mesocotyl, oat 1st leaf and cucumber hypocotyl assays. Gibberellin A25was consistently less active than gibberellin A24and was anactive over the tested range in the oat 1st leaf assay.
展开▼
