Nematicidal toxicity of Calotropis procera and Parthenium hysterophorus extracts on pre-adults of Rotylenchulus reniformis

Direct contact assay of four concentrations of root and leaf extracts of Calotropis procera and Parthenium hysterophorus revealed in general higher mortality of pre-adults of Rotylenchulus reniformis race A as compared to check. There was significantly higher mortality of the nematode in higher doses than in lower ones. The activity significantly increased with increase in the exposure periods from 24 to 48 hrs in all the treatment. Aqueous extract of leaf of Calotropris was more toxic than leaf extract of Parthenium. Whereas acetone root extract of both plant species werefound to be significantly better. The penetration and subsequent development of R. reniformis in sunflower seedlings was significantly suppressed by 4% of both, aqueous and acetone extracts of Calotropis as compared to Parthenium extracts. The % penetration was maximum in control and the lowest was recorded with acetone extract of Calotropis followed by Parthenium extracts attributing to nematostatic effect.