Plants, like humans, can also get wounded. These wounds can be caused by several agents and are a breach of the outer protective layers (the skin) of plants, giving open access to many microbial pathogens that can cause severe diseases, resulting in dramatic crop losses for farmers.
Herein we present a material to avoid contamination and heal plant wounds. This solution is based on the use of an environmentally friendly nanocomposite patch made of bacterial cellulose and silver nanoparticles.
Currently, the efficacy and efficiency of the pesticides used to fight crop infections still face many challenges. Seeking to improve them, we have anchored antipathogenic silver nanoparticles, to the bacterial cellulose structure. An advantage of this biopolymer is that its molecular structure is similar to plant cellulose, one of the plant’s main structural components. Moreover, due to its high-water holding capacity, bacterial cellulose has a hydrogel-like consistency, which increases its adherence to the plant leaves. The wound healing properties of bacterial cellulose have already been patented. The hybrid patch avoids runoff loss and rolling down of the nanoparticles, providing a slow and effective release of the pesticide effects from the bacterial cellulose and safety to our environment.
We have demonstrated the positive antibacterial and antifungal properties of these hybrid patches in in vitro assays against Escherichia coli and two agro-economically relevant pathogens: the bacterium Pseudomonas syringae and the fungus Botrytis cinerea. In addition, in vivo infection inhibition was proved in two different plants (Nicotiana benthamiana and tomato plant leaves).
Enhancing Localized Pesticide Action through Plant Foliage by Silver-Cellulose Hybrid Patches Alejandro Alonso-Díaz, Jordi Floriach-Clark, Judit Fuentes, Montserrat Capellades, Núria S. Coll, Anna Laromaine
ACS Biomater. Sci. Eng. 5 (2), pp 413–419, 2019
Figure: (Left) Tomato plant leaves covered with bacterial cellulose (left), plant cellulose (top) and the silver nanoparticles-bacterial cellulose hybrid patch (bottom) at the site of infection with the bacterial pathogen Pseudomonas syringae pv tomato, causing agent of bacterial speck. (Right) Schematics of the placing of the antibacterial patch on the infected leaves.