Exploring the nano-fungicidal efficacy of green synthesized magnesium oxide nanoparticles (MgO NPs) on the development, physiology, and infection of carrot (Daucus carota L.) with Alternaria leaf blight (ALB): Molecular docking
Lukman Ahamad, Azmat Ali Khan, M. Rizwan Khan, Farid Orudzhev, Mahboob Alam
Abstract
In this research, green synthesized MgONPs from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot (Daucus carota L.) under greenhouse conditions.The scanning and transmission electron microscopy (SEM, TEM) and ultra-violet (UV) visible spectroscopy were used to validate and characterize MgONPs. The crystalline nature of MgONPs was determined using SAED (selected area electron diffraction). MgONPs triggered substantial antifungal activity against A. dauci when exposed to 50 and 100 mg L−1 concentrations but the higher antifungal potential was noticed in 100 mg L−1 under in-vitro conditions. In fungal inoculated plants, a marked decrease in growth, photosynthetic pigments, and an increase in phenol, proline contents, and defense-related enzymes of carrot were seen over control (Distilled water). However, foliar application of MgONPs at 50 and 100 mg L−1 resulted in significant improvement of plant growth, photosynthetic pigments, phenol and proline contents, and defense enzymes activity of carrots with and without A. dauci infection. Spraying of MgONPs at 100 mg L−1 had more plant length (17.11%), shoot dry weight (34.38%), plant fresh weight (20.46%), and root dry weight (49.09%) in carrots when challenged with A. dauci over inoculated control. The leaf blight indices and percent disease severity were also reduced in A. dauci inoculated plants when sprayed with MgONPs. The non-bonding interactions of Alternaria genus protein with nanoparticles were studied using molecular docking.