Seed Coating Formulations for Enhancing Seedling Vigor and Physiological Traits of Moong bean (Vigna radiata L.) and Rice (Oryza sativa L.)

Seed coating with bioactive materials is a promising strategy to enhance seedling vigor, improve germination, and promote early growth. This study was conducted under laboratory conditions using a seed germinator to evaluate the effects of various seed coating formulations on seedling growth and physiological parameters of moongbean ( Vigna radiata ) and rice ( Oryza sativa ). Eight treatment combinations were tested, including biochar, NPK-solubilizing plant growth-promoting rhizobacteria (PGPR), and zinc oxide (ZnO) nanoparticles, either alone or in combination. The experiment assessed germination percentage, root and shoot length, fresh and dry weight, vigor indices, root/shoot ratio, water content, and fresh/dry weight ratio. Results revealed that the combined treatment (T8: Biochar + NPK Microbes + ZnO nanoparticles) significantly outperformed all other treatments, followed by T7 (NPK Microbes + ZnO nanoparticles), in both crops. PCA and correlation analysis underscored the positive interaction of these coating materials, revealing a strong association between vigor indices, germination percentage, and seedling biomass under T8: Biochar + NPK Microbes + ZnO nanoparticles treatment as compared to T1 Control. This study reveals the synergistic effect of nano and bio inputs integrated through seed coating technology for enhancing the early establishment of crops. The results provide insight on sustainable seed enhancement technologies with less chemical dependency that perform better in the crop during the initial stages.