Changes in endogenous hormones and seed-coat phenolics during seed storage of two Suaeda salsa populations

Abstract

Changes in endogenous hormones and seed-coat phenolics during the storage of the dimorphic seeds of two Suaeda salsa populations were investigated. The results showed that, regardless of salinity, storage did not reduce the germination of brown or black seeds from an inland population, but it significantly decreased the germination of dimorphic seeds from an intertidal population. Abscisic acid (ABA) concentration was significantly higher in old seeds than in fresh seeds (freshly harvested dry seeds), whereas the opposite trend was evident for gibberellic acid (GA, including GA1 and GA3) concentration and GA : ABA ratio in both populations, and especially in the intertidal population. Concentration of seed-coat phenolics extracted from brown seeds was much higher than in black seeds in both populations, regardless of extracting time and storage. Storage increased the concentration of phenolics extracted from brown seeds in the inland population, whereas the opposite trend was evident in the intertidal population. Storage did not significantly change seed-coat phenolics extracted from black seeds relative to brown seeds in either population. The results indicated that changes in seed vigour during storage in dimorphic seeds of the two S. salsa populations are related to changes in endogenous hormones and seed-coat phenolics.