EVALUATION OF SOME MEDICINAL PLANT EXTRACTS FOR THEIR NEMATICIDAL PROPERTIES AGAINST ROOT-KNOT NEMATODE, MELOIDOGYNE INCOGNITA

摘要

Nematicidal activities of some plant extracts were assayed against Meloidogyne incognita.. Six different medicinal plants were collected from Swat valley of Pakistan. Plants were moderately washed with tap water in order to remove various impurities like dust, dirt and adhering materials. The plants were shade dried and powdered. Aqueous Methanolic extraction of the dried powdered samples were carried out through cold percolation technique followed by removal of the solvent using vacuum rotary evaporator under controlled temperature. The methanolic crude extracts were further fractionated using different polarity solvents n-hexane, chloroform, ethyl acetate, and n-butanol. Methanolic extracts were screened for egg hatchability and nematicidal activity against second stage juveniles of M. j incognita. in the laboratory under the microscope. The nematode eggs and juveniles were exposed 24, 48 and 72 hrs in different concentrations (10, 100, 1000 ppm) of plant extracts. The plant extracts of Acacia modesta (roots), Segeratia thea (leaves), and Celtis caucasic (aerial part) exhibited highly promising mortality of more than 60% after 72 hrs exposure. There was a gradual decrease in egg hatching with increase in extract concentration of Acacia modesta (roots), Segeratia thea (leaves), and Celtis caucasic (aerial part) were found to be the most effective in reducing egg hatching. Larval mortality were strongly influenced by concentration of extract, plant species and duration of period.