Revista Colombiana de Entomología
Print version ISSN 0120-0488
SALDARRIAGA O, YAMILLE; VASQUEZ P, CARMEN A and CALLE O, JAIME DE JESUS. Virulence of Beauveria bassiana and Triflumuron on Rhodnius prolixus and R. pallescens (Hemiptera: Reduviidae). Rev. Colomb. Entomol. [online]. 2005, vol.31, n.2, pp. 177-182. ISSN 0120-0488.
The virulence of a combination of Beauveria bassiana and Triflumuron on R. prolixus and R. pallescens was evaluated. The bioassays consisted of spraying the insects with conidial suspensions of B. bassiana in concentrations of 3X105, 1X107, and 3X108conidia/ml, with Triflumuron insecticide at 0,05; 0,025; and 0,0125 ug/ul and with a mixture of Triflumuron and B. bassiana. The mortality response and conidiation of the fungi on the triatomine were compared as a function of time and the concentration applied. The results were variable: both R. proxilus and R. pallescens differed significantly between all B. bassiana treatments at concentrations of 3x108 (X2= 148.4), 1 x 107 CX-= 1 1 1.6) y 3x 105 and 3X105 conidia/ml (X2= 195.5); 3x105 (X2= 174.0). 1 x 107 (X2=l4.35) and 3x 105conidia/ml (X2= 18.85), respectively. R. prolixus exhibited shorter survival limes than R. pallescens at concentrations of 3X108 and 1X107 conidia/ml of B. bassiana. The conidiation of B. bassiana on the insect differed significantly among treatments and species of insect, with R. prolixus showing shorter times to conidiation. At 3X108 conidia/ml concentration of B. bassiana, either alone or with the insecticide, there was a lower time to conidiation in both species. The importance of these results is highlighted within one of the tenants put forward in integrated pest management programs initially established by Hurpin in 1966, which affirms that treating insects with high concentrations of conidia and low insecticide concentrations makes them more susceptible to conidiation.
Keywords : Insecticide; Triatomine; Integrated control; Entomopathogen; Combination.