A comparative assessment of the effect of two structurally different chitosan–silver nanocomposites (Ch–Ag 1 and Ch–Ag 2) on plant resistance to Phytophthora infestans, the state of the pro-/antioxidant system, the transcriptional activity of PR protein genes, and potato productivity was carried out. The dependence of the biological activity of Ch–Ag nanocomposites on their structure has been revealed. The mechanisms of activation of potato defense systems under the influence of Ch–Ag nanocomposites were mediated by the accumulation of hydrogen peroxide, a decrease in catalase activity, and an increase in the transcription of genes encoding PR proteins: chitinase (PR-3), thaumatin-like protein (PR-5), RNase (PR-10), and methyltransferase (MT). It was shown that treatment with Ch–Ag 2 reduced the degree of damage to the leaves of P. infestans and increased the mass of potato mini-tubers. The data obtained indicate that chitosan–silver nanocomposites are promising biological products for increasing the stability and productivity of potatoes.
Yarullina et al. (Wed,) studied this question.