Phytochemical Insights and Acetylcholinesterase-Targeted Nematicidal Activity of Digitalis purpurea L. Extracts in Biological Control of Meloidogyne incognita.

Digitalis purpurea L. is traditionally valued for its cardiac glycosides, but its pesticidal properties remain underexplored. This study evaluated its nematicidal efficacy against Meloidogyne incognita, focusing on acetylcholinesterase (AChE) inhibition as a potential mechanism. Extracts obtained using Soxhlet extraction with hexane (DPHE), dichloromethane (DPDE), and methanol (DPME) were analyzed via GC-MS. DPHE contained fatty acids, including hexadecenoic acid (20.38%) and linoleic acid (14.43%). DPDE was rich in bioactives like gitogenin (8.89%) and digitoxigenin (6.8%). DPME featured β-d-glucopyranose, 1,6-anhydro (15.55%), and smilagenin (5.49%). Nematicidal assays showed DPDE achieved 100% mortality at 1000 µg/mL and 91.23% egg-hatching inhibition. It also demonstrated 87.88% AChE inhibition, surpassing physostigmine (81.75%). Molecular docking revealed strong interactions between DPDE compounds and AChE. These findings suggest D. purpurea, particularly its dichloromethane extract, as a promising eco-friendly nematicidal agent.