Indian Journal of Plant Physiology

Reactive oxygen species (ROS), besides having deleterious effects also participate in developmental processes including seed germination. In this investigation attempt has been made to establish the role of ROS and oxidative metabolism in regulation of seed germination of Vigna radiata. Treatments with reducing agents like -mercaptoethanol (BME) and dithiothreitol (DTT) during incubation retarded seed germination significantly and simultaneous treatment with hydrogen peroxide (H₂O₂) partially overcame such inhibition. This was reflected in the rate of water uptake and elongation of isolated embryonic axes. Propyl gallate (PG), a ROS scavenger, inhibited seed germination and retarded water uptake and elongation of isolated axes, which could also be ameliorated partially by H₂O₂ treatment. However, potassium iodide (KI), being a specific H₂O₂ scavenger, could not affect germination. Treatment with ethrel partially recovered germination from inhibition by reducing agents and PG, being more effective against BME. A possibility of direct involvement of some H₂O₂- derived ROS and ethylene in regulation of seed germination has been proposed.