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A soil sample (500 g) was collected from pure culture of H. zeae, maintained on maize plants (CWM-19), the commercially available cultivar, in microplots of a screen house, National Nematological Research Centre, University of Karachi. The emerged larvae were collected from the soil by Baermann funnel technique. After larvae had been counted in a counting chamber, 100 larvae were placed in a cavity block with a minimum amount of water for bioassayFor the pure compounds, 1 mg/mL was the stock solution (3,4,5-Trimethoxybenzoic Acid in DMSO)), and 1.0, 0.5, 0.25, and 0.125% dilutions were prepared from the stock. The standard nematicide carbofuran was used for the comparison, and distilled water was used as the control. Stock solution of positive control, that is, carbofuran was also prepared in the same manner as for extracts and pure compounds. The nematicidal activities of 5% dimethyl sulfoxide (DMSO) and 5% methanol used as the solvent and as negative controls were also determine. To determine the nematicidal effect of methanol and DMSO soluble fractions and pure compounds, 100 freshly hatched second-stage juveniles were introduced separately in each 3 x 3 glass Petri plates with the three replicates. Petri plates were kept at room temperature (28 +/- 2 C) in the laboratory and dark box conditions. Each treatment was observed in light and dark conditions separately and replicated three times. The mortality of the nematodes was examined under a stereoscopic microscope at 4C after 24 h. In the case of immobile larvae, their irreversible immobility was confirmed by transferring them to distilled water. The percent mortality was calculated from an average of three replicates (N = 3). This procedure was repeated after 48 and 72 h.