Revista Facultad Nacional de Agronomía, Medellín
versão impressa ISSN 0304-2847
TRUJILLO RUIZ, Paula Andrea et al. DETERMINATION OF THE LD50 AND THE LT50 ETHANOLS EXTRACTS OF CELLULAR SUSPENSIONS FROM Azadirachta indica OVER Spodoptera frugiperda. Rev.Fac.Nal.Agr.Medellín [online]. 2008, vol.61, n.2, pp. 4564-4575. ISSN 0304-2847.
The production in vitro of secondary metabolites from neem arises like an alternative for the possible industrial processing of biocidas. In the search of alternatives for the control of Spodoptera frugiperda, were evaluated ethanolic extracts of cellular suspensions from Azadirachta indica in order to determine the DL 50 and the TL50 on the larval state of the second instar (L2). Four concentrations of the extracts (2.500, 5.000, 10.000, and 30.000 ppm) and the control (alcohol 96%) to determine mortality in the time (0, 12, 18, 25, 40 hours) were compared. It was determined a DL50 at the 12 hours of 2.256 ppm, (R2 = 88, 54%), at the 18 hours of 3.928 ppm, (R2 = 90,30%), at the 25 hours of 2.818 ppm, (R2 = 90,30%) and at the 40 hours of 1.064 ppm, (R2 =90,30%). The doses of 5.000 ppm, 10.000 ppm and 30.000 ppm, didn't present differences statistically significant in their lethal action, but were effective in the insect control.
Palavras-chave : Cellular suspensions; neem; model of discrete election (probit); secondary metabolitos; corn borer.