Assessment and nematicidal activity of Cu/Fe and Zn/Fe bimetallic nanoparticles against root-knot nematode in beetroot and cabbage

This research intended to evaluate the potency of bimetallic nanoparticles (BMNPs) and Cyclotella meneghiniana on two pivotal plant parasitic nematodes (PPN). A preliminary in vitro experiment was conducted to screen the effectiveness of both control materials against Meloidogyne incognita and Scutellonema bradys. C. meneghiniana displayed very weak activity on hatching inhibition of M. incognita eggs and mortality of S. bradys individuals. Potent action was recorded in BMNPs on M. incognita juvenile mortality and egg hatch inhibition. The suppressive action of BMNPs on M. incognita was assessed in vivo on infected beetroot (Beta vulgaris L.) and cabbage (Brassica oleracea L.) in a field experiment laid out in randomised complete block design. Activity of BMNPs was concentration dependent. Copper/iron nanoparticles (Cu/Fe NPs) enhanced yield and vegetative parameters of both plants. Cu/Fe exhibited higher antioxidant activity in comparison with Zn/Fe, thus explaining the potency of Cu/Fe on most parameters evaluated. High resolution transmission electron microscopy (HRTEM) confirmed particle size of ZnO/Fe₂O₃NPs and Fe₂O₃/CuO NPs to be 12.5 nm and 15.4 nm, respectively. High angle annular dark-field (HAADF STEM) identified the compositional distribution of each element, while selected area diffraction (SAD STEM) confirmed the crystalline nature of BMNPs . Bimetallic NPs are a good proposal for M. incognita management on beetroot and cabbage plants.