Dual Functional Biodegradable Carboxymethylcellulose–Zinc–Cobalt Cross-Linked Hydrogel Beads with Inherent Biocidal Property for Multinutrient Fertilization: An Experimental Study with Theoretical Insights

Water management, nutrient use efficiency, and pathogen prevention are the major parameters that are critical to optimize crop yields. Alternate approaches to manage these parameters are of the utmost importance. A dual-functionality biodegradable hydrogel with an inherent biocidal property and multinutrient delivery could be of potential interest. Nitrate-loaded carboxymethylcellulose–zinc–cobalt (CMC-Zn-Co) cross-linked hydrogel beads showed excellent swelling/deswelling behavior and were effective against two major plant pathogens, Xanthomonas citri. pv. citri and Ralstonia solanacearum, which cause wilt disease in plants. The hydrogel matrix facilitates the slow release of nitrate and eventual discharge of Zn and Co upon degradation. Density functional theory (DFT) studies reveal the interaction of Zn 2+ and Co 2+ ions with the CMC upon bead formation. Environmentally benign CMC-Zn-Co cross-linked hydrogel beads could be a one-stop solution for multinutrient fertilization, water management/soil conditioning, and pathogen prevention that would limit the administration of multiple agents, lowering production cost and boosting environmental sustainability.