Seed Priming Improves Rice Seed Tolerance to Salinity Stress: Unveiling Through Multivariate Analysis

Salinity stress is a major constraint affecting rice establishment and productivity in many coastal and salt-affected regions of the world, as well as in Bangladesh. Seed priming has emerged as an effective technique to enhance seed germination, seedling vigor and growth, and stress tolerance. To address this challenge, the present study investigated the potential of four different seed-priming agents (non-, hydro-(H2O), osmo-(Polyethylene glycol, 30%), nano-(Zinc EDTA (12%), and 170 ppm) applied to two rice varieties (Binadhan-10 and BINA dhan25) under four levels of salinity stress (0, 5, 8, and 11 dS m−1), with the aim of enhancing germination, improving the seedling vigor index, and promoting early growth performance in a completely randomized design with four replications. Nano-priming with Zinc EDTA (12%, at 170 ppm) involves soaking seeds in a solution containing this concentration of zinc chelate, which can improve seedling vigor and stress resilience, especially under challenging conditions like salinity. The results indicated that salinity significantly reduced germination and seedling growth, whereas seed priming improved seed performance under stress conditions. Among the treatments, nano-priming showed the most pronounced improvement in germination and seedling vigor. Binadhan-10 exhibited a greater tolerance to salinity compared with BINA dhan25. Multivariate analyses, including principal component analysis, correlation analysis, and heatmap, revealed strong positive relationships among germination, vigor index, and seedling biomass traits. The findings demonstrate that seed priming, particularly nano-priming, can effectively enhance rice seed germination, the vigor index, and different seedling traits under saline conditions, providing a promising strategy for improving rice production in salt-affected areas in Bangladesh.