Zinc Nanoparticles and their Antifungal Activity against Alternaria burnsii Causing Blight of Cumin

Zinc nanoparticles (ZnNPs) produced was evaluated against Alternaria burnsii to see the inhibitory result of the ZnNPs on the growth of fungal mycelium. Physical characterization of synthesized ZnNPs was 68.04 nm in size, Pdi- 0.263, Keps-252.4. Among the twelve treatments, the best treatment was synthesized ZnNPs with concentration (750 ppm) evidenced most in effect with 86.17 per cent mycelial growth is inhibited. The next treatment was synthesized ZnNPs with concentration (250 ppm) giving 79.26 per cent growth inhibition. Followed by treatment commercial ZnNPs with concentration (1000 ppm) giving 53.46 per cent growth inhibition. The next effective treatment was commercial ZnNPs with concentration (500 ppm) giving 44.69 per cent growth inhibition. Followed by treatment of carbendazim 50 WP with concentration (500 ppm) giving 11.51 per cent growth inhibition. The least effective treatment was commercial ZnNPs with concentration (100 ppm) giving 3.22 per cent growth inhibition. There is directly proportional relationship between increased concentration of the ZnNPs and inhibition of per cent mycelial growth of the pathogen is directly proportional. Further, methylene blue staining was done and the physical changes were studied. The hyphae lost their softness, bulges out followed by reduction in the distance between two hyphae. Branched conidia turned round and conidial development was suppressed. On the basis of this result it can be concluded that ZnNPs inhibited the fungal growth by causing physical damage to the fungal mycelium.