A comparative study of the effect of linear chitosan (Сh) and the globular form of chitosan, novochizol (Nc), on the growth and development of spring bread wheat, as well as protection against a complex of fungal diseases under epidemic conditions, was carried out. The indicators “Area Under the Disease Progress Curve” (AUDPC) and “Resistance Index” (RI) were calculated based on the observations. The research results showed that the Ch had greater growth-stimulating activity (on seed germination, stem and ear formation, and seed setting) and a protective effect against biotrophic and hemibiotrophic pathogens than Nc. The Nc–SA preparation (complex with 0.01% salisylic acid) showed the greatest protective effect, which increased in relation to the following diseases: leaf rust, stem rust, Septoria tritici blotch, and Septoria nodorum blotch. The increase in grain yield in the Ch-treated variants was mainly due to the growth-stimulating effects, while the Nc–SA treatment provided better protection against a range of diseases caused by the fungi with different feeding types.
Plotnikova et al. (Wed,) studied this question.