Hydrogels are gaining prominence in sustainable agriculture due to their water-retention capacity and tunable physicochemical properties. Among this broad class of materials, natural polymer-based hydrogels have received increasing attention, and alginate is particularly attractive because it can form hydrogels, providing a versatile platform for controlled release, soil conditioning, and environmental remediation. In this review, an integrated analysis of research trends, technological developments, and emerging technologies for alginate hydrogels and derived formulations used in agriculture was conducted based on both scientific and global patent documents available between 2001 and 2024. A total of 266 scientific articles and 460 patent families were identified, revealing sustained growth in both research output and technological development. Advances in encapsulation and controlled-release systems overwhelmingly dominate the landscape, accounting for 38% of global patent families in this domain, followed by soil and water treatment applications. Postharvest preservation, in vitro cultivation, and biodegradable packaging are emerging as expanding areas of research. Crucially, a significant technology-readiness gap is identified despite robust research activity: studies remain predominantly at the in vitro (41.4%) or semi-controlled greenhouse (39%) stages, with only a limited fraction (19.6%) progressing to field trial validation. By integrating patent and scientific literature, this review provides a unique framework for identifying technological gaps in the development of alginate hydrogels as a multifunctional platform for precision agriculture and sustainable production within the bioeconomy.
Diestra-Balta et al. (Fri,) studied this question.