3β,13-dihydroxylated C₂₀ gibberellins from inflorescences of Rumex acetosa L.

Using full scan GC-MS a wide range of gibberellins (GAs) was identified in the young inflorescences of the dioecious species Rumex acetosa L., consistent with the ubiquitous early 13-hydroxylation pathway in both male and female plants. In addition, R. acetosa is the first species in which all three 3β, 13-dihydroxylated C₂₀-GAs - GA₁₈, GA₃₈ and GA23 - have been identified in the same organism, suggesting an early 3β,13-dihydroxylation biosynthesis pathway in this species. Authentic GA₁₈, GA₃₈ and GA₂₃ were synthesized and their effects and that of GA₁, a GA common to both pathways, on the time to inflorescence emergence was investigated. GA₁ accelerated the emergence of inflorescences in both male and female plants. In addition some evidence for biological activity per se of the C₂₀-GA₃₈ was obtained.