A Novel Bis-Trifluoromethylated Compound Demonstrates High Efficacy as a Nematicide Against Root-Knot Nematodes on Pistachio, Supported by Docking Studies.

Abstract

Three novel trifluoromethylated compounds were designed and synthesized by reacting trifluoroacetimidoyl chloride derivatives with acetamidine hydrochloride or thiourea in the presence of potassium carbonate or sodium hydrogen carbonate as a base. In vitro and in vivo assays demonstrated the efficacy of the tested compounds in controlling root-knot nematode disease on pistachio rootstocks caused by Meloidogyne incognita. Bis-trifluoromethylated derivatives, namely N,N''-thiocarbonylbis(N'-(3,4-dimethylphenyl)-2,2,2-trifluoroacetimidamide) (compound A1), showed high efficacy as novel and promising nematicides, achieving up to 78.28% control at a concentration of 0.042 mg/liter. This effect is attributed to four methyl and two trifluoromethyl groups. In the pre-inoculation application of compound A1, all three concentrations (0.033, 0.037, and 0.042 mg/liter, and Velum) exhibited a higher level of control, with 83.79, 87.46, and 80.73% control, respectively. In the microplot trials, compound A1 effectively reduced population levels of M. incognita and enhanced plant growth at a concentration of 0.037 mg/liter. This suggests that compound A1 has the potential to inhibit hedgehog protein and could be utilized to prevent the progression of root-knot disease. Furthermore, the molecular docking results revealed that compounds A1 and A3 interact with specific amino acid residues (Gln60, Asp530, Glu70, Arg520, and Thr510) located in the active site of hedgehog protein. Based on the experimental findings of this study, compound A1 shows promise as a lead compound for future investigations.