Antifungal Efficacy of Zinc Oxide Nanoparticles against Anthracnose and Southern Blight Disease in Green Gram

Abstract

Nanotechnology has rapidly advanced in the 21st century, with significant developments in the synthesis and application of nanoparticles. ZnNps (Zinc nanoparticles) were synthesized using extracts from mehandi (Lawsonia inermis), neem (Azadirachta indica), marigold (Tagetus erecta) and ginger (Zingiber officinalis). ZnNps were synthesized after analyzing the compatability of the plant extracts with the test pathogens. This study investigates the antifungal activity of green synthesized zinc nanoparticles (ZnNps) in the laboratory against Colletotrichum lindemuthianum, the causative agent of anthracnose in mung beans and Sclerotium rolfsii causing southern blight in mung bean using the poisoned food technique. Various concentrations (100ppm, 250ppm and 500ppm) of zinc nanoparticles derived from neem, mehandi, marigold and ginger were evaluated alongside corresponding plant extracts and Zinc nitrate hexahydrate at 250ppm. Results indicated significant fungistatic activity, with Mehandi ZnNps at 500ppm exhibiting the highest efficacy, demonstrating minimal mycelial growth (28.00mm) and a growth inhibition rate of 68.88% followed by Marigold and Neem ZnNps against Colletotrichum. As for Sclerotium, Neem ZnNps at 500 ppm exhibiting the highest efficacy, demonstrating minimal mycelial growth (15.00 mm) and a growth inhibition rate of 83.33% followed by ginger and Mehandi. All tested ZnNps concentrations outperformed their respective plant extracts and Zinc nitrate hexahydrate, confirming the potential of green synthesized ZnNps as effective agents. This study provides an eco-friendly alternative to chemical fungicides, addressing the increasing need for sustainable agricultural practices to combat fungal diseases in mung beans. These findings underscore the potential of green synthesized ZnNps as effective ecofriendly fungicides.