Bacterial cellulose in sustainable agriculture: bibliometric map and critical review of agronomic applications and waste-valorised production

Bacterial cellulose (BC) is a lignin-free nanofibrillar hydrogel with high water-binding capacity, mechanical strength, and biodegradability. Despite these properties, a Scopus bibliometric survey of 738 publications (2015-2025) showed that agricultural applications accounted for only 17% of BC research, while biomedical and materials-science applications dominated. This review contributes a bibliometric quantification of that imbalance; a four-function synthesis of BC as a cultivation substrate, soil amendment, seed or biological carrier, and agrochemical platform; and a production route-property-application matrix linking waste feedstocks to agronomic functions. Direct crop evidence remains limited. In a controlled tomato-seedling study, 0.01% BC increased substrate water-holding capacity by up to 14% and improved survival, root development, and nutrient availability under restricted irrigation. Supporting evidence from plant-derived cellulose and other biopolymer hydrogels demonstrates improved germination and soil moisture regulation, but should not be interpreted as direct validation of BC. Feedstock selection affects production cost, material properties, and application fit simultaneously. Multi-season field trials, matched comparisons with commercial substrates and hydrogels, standardised characterisation, and life-cycle and techno-economic assessments remain priorities.