Potato virus Y (PVY) stands as the prevalent viral pathogen in affecting potatoes in most countries. Effective prevention strategies necessitate comprehensive protection against pathogens and abiotic stresses, which includes modeling the beneficial microbiomes of in agroecosystems by combining microorganisms with immunostimulants. Chitosan derivatives demonstrate significant potential for use in agricultural due to their capacity to induce plant immune responses. This study investigated the antiviral activity of chitosan-silver nanocomposite (Ch-AgNCs) at two concentrations with Bacillus subtilis 47. Foliar application of Ch-AgNCs combined with B. subtilis 47 resulted in substantial inhibition of viral infection of plant leaves. Concurrently, treated plant tissues exhibited a marked increase in ribonuclease activity, specific groups of proteolytic enzymes, hydrogen peroxide content. This was accompanied by a decrease in the activity of protease inhibitors, as well as reduced lipid peroxidation. The effect of the studied compounds with B. subtilis 47 contributed to an elevated expression of protective protein genes in healthy plants. This subsequently led to a reduction in severity of PVY infection and a decrease in the transcript levels of stress genes. The Ch-AgNCs with B. subtilis 47 led to a reduction in the number of mini-tubers formed, while simultaneously enhancing their mass.
Kalatskaja et al. (Tue,) studied this question.