Development of bio‐nano‐herbicide using Eucalyptus citriodora essential oil against a notorious weed Echinochloa crus‐galli

BACKGROUND: Weeds are a menace in agriculture causing crop yield reductions to the tune of 40-50%. To overcome the problems of weeds, herbicides have been used excessively to the extent that they have caused resistance in weeds, in addition to the environmental hazards. Nano-herbicides are intended to exploit botanicals to develop novel bio-nano-herbicide formulations. Bio-nano herbicide was developed using Eucalyptus citriodora essential oil combined high-energy approaches such as ultra-sonication and high-pressure homogenization. The formulation has hydrodynamic and physical sizes of 95.5 and 32.3-57.7 nm, respectively. The product was tested for their pre-emergence and post-emergence herbicidal activity against Echinochloa crus-galli. RESULTS: ). The antioxidant enzyme activities increased immediately after the first spray and the weeds wilted after the second spray. CONCLUSION: This study is a maiden attempt to clearly demonstrate that bio-nano-herbicide can be developed using Eucalyptus citriodora essential oil which has both pre-emergence and post-emergence inhibitory activities against the notorious weed Echinochloa crus-galli. Field studies are to be taken up in the near future to validate the herbicidal efficacy of the novel nano herbicide formulation. © 2025 Society of Chemical Industry.