Phenolamides during the ripening of dormant and non‐dormant seeds in different Petunia lines

Abstract

Phenolamides were extracted from reproductive organs and different capsule parts (fruit wall, placenta and seeds) of dormant and non‐dormant lines derived from the species Petunia hybrida hort,. Petunia axillaries Lam. B.S.P. and Petunia parodii Steere. The different compounds were separated by high‐pressure liquid chromatography and analyzed before pollination, during ripening, at ripeness and after 2 weeks of after‐ripening of the seeds. The extracts were examined particularly for the presence of an alkaline compound (X), which is a phenolic derivative of tryptophanamide and appears to be a biochemical marker for the dormancy of ripe dry seeds of Petunia. During capsule growth and seed ripening, compound X was not a marker for dormancy, although it occurred in the reproductive organs of seed‐parent plants. After pollination and fertilization, accumulation of compound X started mainly in the fruit wall, but in ripe dry capsules it was present entirely in the seeds. In contrast to compound X, neutral phenolamides were not detected in extracts from the fruit wall: and from the early stages of the capsule growth substantial accumulation took place only in the seeds.Absence of compound X from ripe dry seeds appears as a necessary but not a sufficient condition for non‐dormancy.