Assessment of antifungal activity of nano-chitosan against mung bean seed borne pathogen Aspergillus flavus through solid matrix priming

Abstract

Seed borne pathogens are one of the major causes of reducing crop yield worldwide. In the present investigation, the most common seed borne pathogen of mung bean, Aspergillus flavus was isolated and identified, and the inhibitory effects of different concentrations of nano-chitosan against the fungal growth and spore germination of Aspergillus flavus were evaluated for its effective management. The emergence and seedling vigor in post-primed inoculated mung bean seeds were also tested. Results clearly showed the antifungal activity of nano-chitosan against Aspergillus flavus. Nano-chitosan arrested the growth of fungal colonies and germination of spores in a dose-dependent manner. Solid matrix priming with nano-chitosan improved the biotic stress tolerance of mung bean seeds against Aspergillus flavus infection and also improved the seedling vigor measured in terms of increased root length, shoot length, fresh weight, and dry weight along with various stress tolerance indices. It was observed that among all the treatments applied, Aspergillus flavus inoculated mung bean seeds primed with 571μg / ml nano-chitosan with 10% matrix (Celite) moisture level showed the optimum antifungal activity. These observations lead to the conclusion that nano-chitosan can be effectively used as ideal priming agent in preventing seed borne fungal infections and can also improve the seedling vigor.