Effects of chitosan-based film coating formulations containing essential oil on potato seed performance and some fungal pathogens

This study was conducted in 2023 and 2024 to determine the effects of film coating applications with chitosan-based nanoemulsion formulations containing essential oils on plant growth, tuber yield, and some fungal pathogens in potato (Solanum tuberosum L.). Film coating applications were made with nanoemulsions created using different doses and combinations of essential oils from thyme (Thymus vulgaris), Turkish pickling herb (Echinophora tenuifolia subsp. sibthorpiana, clove (Syzygium aromaticum), cinnamon (Cinnamomum zeylanicum), eucalyptus (Eucalyptus globulus), dill (Anethum graveolens), juniper (Juniperus communis), and ginger (Zingiber officinale) on potato tubers. The effects of essential oils and chitosan on sprout development in potato tubers were determined under greenhouse conditions, while their antifungal activities against Rhizoctonia solani and Fusarium solani were evaluated in vitro. The impact of film formulations on sprout vigor and plant growth was assessed in a plant growth chamber, their antifungal activities against R. solani and F. solani were tested in greenhouse and field conditions, also their effects on tuber yield were investigated under field conditions. Essential oil applications significantly affected sprout development in potato tubers, with the most effective applications being thyme, clove, dill, and Turkish pickling herb essential oils. In in vitro studies, clove and thyme essential oils demonstrated the highest antifungal activity against both phytopathogens. Nanoemulsion film formulations reduced the tuber infection rate by F. solani by 88% and the tuber infection rate by R. solani by up to 80%, compared to the control. Film coating applications increased the number of tubers and tuber yield per plant by over 40%, and the total tuber yield by more than 45%, while significantly reducing the infection rate of tubers by F. solani and R. solani. The study concluded that the developed nanoemulsion formulations can be successfully used to increase tuber yield in potatoes and for natural control of phytopathogens.