Detoxification of parthenium (Parthenium hysterophorus) and its metamorphosis into an organic fertilizer and biopesticide

BACKGROUND: Vermicompost of the toxic and allelopathic weed parthenium (Parthenium hysterophorus) was explored for its possible use as an organic fertilizer. Replicated plant growth trials were conducted using four levels of parthenium vermicompost (0, 2.5, 3.75, and 5 t/ha) to assess their effects on the germination, growth, and fruition of a typical food plant ladies finger (Abelmoschus esculentus). Additionally the role of vermicompost in reducing plant pests and disease was evaluated. RESULTS: Vermicompost encouraged the germination and growth of ladies finger at all levels of vermicompost application, with best results obtained in 5 t/ha treatments. The positive impact extended up to the fruit yield. Vermicompost application also improved the quality of fruits in terms of mineral, protein, and carbohydrate contents, and reduced the disease incidence and pest attacks. CONCLUSIONS: The studies establish the fact that parthenium acquires all the qualities of a good organic fertilizer with concomitant loss of its toxic and allelopathic properties after it gets vermicomposted. The findings raise the prospects of economical and eco-friendly utilization of billions of tons of parthenium biomass which is generated annually but goes to waste at present.