Use of Starch and Biochar-Based Essential Oil Formulations from Three Aromatic Plants as Antifungal Components to Improve Peanut (Arachis hypogaea L.) Seed Storage

Abstract

Poor storage conditions of foodstuffs are responsible for their deterioration on many microorganism species with substantial quantitative and qualitative losses. During storage, formulating essential oil of some antifungal plants' based on cassava starch and corncob biochar efficacy was evaluated on fungi associated with peanut seeds (Arachis hypogaea L.). Two hundred peanut seeds were dispersed in plastic bottles; 5 g of essential oil formulation starch-based (3 and 7 µl/g) were sprinkled on the seeds. Biochar pieces were added to the seeds in the bottles for biochar-based essential oils. Laboratory conditions were used to store both treatment and non-treatment seeds for 70 days. Infection rates of fungal infections were estimated at 10, 20, 40, 60, and 70 days of storage. From the results obtained, five fungal genera were isolated from peanut seeds, including four species of Aspergillus, Cercospora sp, Fusarium sp, Phomopsis sp and Rhizopus stolonifer, with seed infection percentages ranging from 4 to 62%. The antifungal activity of starch-based formulations revealed that at a concentration of 3 µl/g, Cymbopogon citratus essential oil is the most effective antifungal agent, 13% infection for 70 days resulted storage of peanut seeds. After 70 days of storage, at a dose of 7 µl/g, C. sempervirens essential oil had the best antifungal efficacy with 23.50% of infected seeds for the biochar-based formulation. As a result of these findings, starch and biochar can be used to formulate essential oils for the conservation of peanut seeds. Moreover, Cymbopogon citratus essential oil formulated with starch is the most effective.