Hormonal Response and Seed Viability of Porteresia coarctata, a Brackish Water Species

Stimulation of α-amylase activity was observed in Porteresia coarctata Immature seeds (20-day-old) when de-embryonated prewashed half seeds were Incubated In media containing gibberellic acid (GA₃, 10⁻⁵M). No such activity was observed in mature seeds even when GA, concentration was increased up to five fold. ABA suppressed the GA₃ enhanced α-amylase synthesis up to nearly 70% In the immature seeds. Absence of this enzyme activity in mature seeds may be due to high levels of ABA. The Immature aleurone showed a 23 kD polypeptide induced by ABA.