Bacterial Nanocellulose Mulch as a Potential Greener Alternative for Urban Gardening in the Small-Scale Food Production of Onion Plants

Urban gardening is growing as an increasingly therapeutic, social, mental, environmental, and economical alternative to improve the quality of life. One of the options to enhance this activity is the use of mulches. There are several reports on the use of cellulose-based mulches in rural areas. This work is the first successful study on the use of nanocellulose mulches for small-scale urban food production based on bacterial nanocellulose (BNC) pellicules constituted by nanoribbons. In this case, the pellicules were produced by bacteria isolated from the Colombian species Komagataeibacter medellinensis (previously referred to as Gluconacetobacter medellinensis sp. Nov., a new acid-resistant strain that can grow at a pH as low as 3.5) under simple static conditions. A cheap substrate, such as ripened fruit not suitable for human consumption, was used to produce the BNC mulches. The obtained BNC mulches are cheap and environmentally friendly than plastic mulch based on polyethylene. The effectiveness of BNC pellicule mulches was evaluated during the growth of one type of onion plant under urban garden conditions and was compared with an uncovered system and a commercial polyethylene mulch. Progressive degradation of BNC mulches took place during plant growth, indicating the biodegradability of BNC mulches, and thus, the onion plants exhibited healthy physiological development. The results suggest that BNC mulches are environmentally friendly and easy to use for the protection of small-scale food production in urban areas during short plant-growing periods.