Efecto de cinco concentraciones de extractos acuosos de Pleurotus ostreatus P. Kumm y Tagetes minuta L. en la mortalidad de dos nemátodos en laboratorio.

Abstract

The aim of this study was to evaluate the effect of five concentrations of aqueous extracts of Pleurotus ostreatus and Tagetes minuta on the mortality of the nematodes Meloidogyne spp. and Panagrellus redivivus in the laboratory, using 50 laboratory-reared nematodes of Panagrellus redivivus, which were extracted by suspension in sterile distilled water, and 20 nematodes of Meloidogyne sp. extracted by the tray method. The aqueous extracts were obtained by the hydrodistillation method, then the established concentrations were prepared: 0%, 0.5%, 5%, 25%, 50% and 100%. For the statistical analysis, a completely randomized design of a single factor was used for the aqueous extract Pleurotus ostreatus and a bifactorial design for the aqueous extract of Tagetes minuta leaves and flowers, for both extracts the number of dead individuals was evaluated and the efficacy and Lethal Concentration 50 were determined. The results were: Tagetes minuta leaf against Panagrellus redivivus presented greater nematicidal activity at concentrations: 25%, 50% and 100% with a Lethal Concentration 50: 8.03 ppm, against Meloidogyne sp. at concentrations: 0.5%, 5%, 25%, 50% and 100% with a Lethal Concentration 50: 0.01 ppm. For Pleurotus ostreatus against Panagrellus redivivus the highest nematicidal activity was at concentrations: 5%, 25%, 50% and 100% with a Lethal Concentration 50: 1.22 ppm, against Meloidogyne sp. at concentrations: 0.5%, 5%, 25%, 50% and 100% with a Lethal Concentration 50: 0.01 ppm. It is concluded that the aqueous extracts with the highest nematicidal activity were Tagetes minuta leaf and Pleurotus ostreatus, while the aqueous extract of Tagetes minuta flower showed low nematicidal activity. It is suggested to test Lethal Concentrations 50 of Tagetes minuta leaf and Pleurotus ostreatus on juvenile 2 populations of Meloidogyne sp.