Synthesis, characterization, and in vitro antifungal activity of anionic and nonionic surfactants against crop pathogenic fungi

Fungi have long been identified as causal agents of plant diseases. The development of plant antifungal activity was attempted by synthesis of a new type of anionic and nonionic surfactant. The surface properties were studied, including critical micelle concentration (CMC), effectiveness (πcmc), maximum surface excess (Γmax), and minimum surface area (Amin). Free energy of micellization and adsorption was calculated (ΔG°mic and ΔG°ads). The antifungal activity of the prepared surfactants was verified in vitro by the poisoned food technique against eight phytopathogenic fungi: Colletotrichum dematium, Drechslera hawaiiensis, Fusarium oxysporum, Fusarium solani, Humicola fuscoatra, Pestalotia laurocerasi, Phoma spp., and Phytophthra. The results reported that the percentage inhibition of mycelial growth increases with increasing concentrations of the surfactant for all fungal species used. These results indicated that the surfactant inhibited the mycelial growth of all fungal species in a dose-dependent manner. Blend surfactants have a potential antifungal effect for the control of some phytopathogenic fungi.