Priming

Poor germination and establishment of direct-seeded rice remain significant challenges to achieving optimal crop growth and productivity. Osmo priming is a pre-sowing seed treatment designed to enhance germination and stress tolerance. This study evaluated the effects of Osmo priming on seed germination, seedling growth, and chlorophyll content, aiming to improve drought tolerance in near-isogenic lines (NILs) of the IR64 genetic. Seeds were primed by soaking in a 10% polyethylene glycol (PEG) solution in Petri dishes, using a weight-to-solution ratio of 1:3for both experiments. Treatments were arranged in a completely randomized design with three replications. Two factors were combined: osmotic-induced drought stress during germination and seedling growth, simulated with PEG-6000, along with seed priming at 10% PEG-6000. PEG-induced drought delayed and reduced germination percentage (GP), seedling vigor, seedling growth, chlorophyll content, biomass production, and maximum quantum in the NILs. However, 10% PEG-based Osmo priming effectively mitigated these adverse effects by improving GP, mean germination time (MGT), seedling vigor, seedling growth, chlorophyll content, and PSII performance. These findings suggest that PEG priming enhances osmotic regulation in rice seedlings, facilitating germination and seedling development while alleviating drought stress damage. Overall, PEG-based Osmo priming successfully improv the drought tolerance of IR64-derived NILs