Potassium Nitrate Treatment Is Associated with Modulation of Seed Water Uptake, Antioxidative Metabolism and Phytohormone Levels of Pea Seedlings

(1) Background: Seed treatment with potassium nitrate (KNO3) has been associated dormancy breaking, improved germination and enhanced seedling growth uniformity in a variety of plant species. However, the KNO3 effect seems to be dependent on species conditions. (2) Methods: We describe incubation dry pea seeds different concentration water uptake kinetic, early growth, antioxidant metabolism hormone profile seedlings. (3) Results: Low (0.25 mM) levels increased whereas high (40 decreased growth. differentially affected defences. maintained activity enzymes, while reduced H2O2-scavenging enzymes. induced progressive decline ascorbate (GSH) oxidised (GSSG) glutathione. strongly GA1 ABA both seedlings cotyledons, resulting ABA/GAs ratio. (4) Conclusions: Pea seed low level promoted In this process, an interaction among KNO3, defences ratio is proposed.