Acta zoológica mexicana
versão impressa ISSN 0065-1737
HERNANDEZ DIAZ-ORDAZ, Noé; PEREZ, Nelson e TOLEDO, Jorge. Pathogenecity of three strains of entomopathogenic fungus on Anastrepha obliqua adults (Macquart) (Diptera: Tephritidae) under laboratory conditions. Acta Zool. Mex [online]. 2010, vol.26, n.3, pp.481-494. ISSN 0065-1737.
In order to develop biorrational fruit fly control methods, the activity of two strains of Beauveria bassiana (Bb26 and BbJLSV) and a strain of Metarhizium anisopliae (MaCENGICAÑA) against adults of Anastrepha obliqua was evaluated in the laboratory. The Bb26 strain caused the highest infection rate (99.8%), followed by the BbJLSV strain (93.5%), and the MaCENGICAÑA strain which caused the lowest infection (89.8%). Both males and females were susceptible to the strains tested, with a similar mortality in both sexes. The median lethal time (LT50) was 3.9, 5.3 and 6.4 days for MaCENGICAÑA, Bb26 and BbJLSV, respectively, with an average median lethal time for the three strains of 5.2 days. Results indicate that the most pathogenic strain against adults of A. obliqua was Bb26, with a median lethal concentration (LC50) equivalent to 3.8 x 106 conidia ml-1, followed by the MaCENGICAÑAstrain equivalent to 4.8 x 106 conidia ml-1 and the BbJLSV strain with an equivalent to 8.8 x 106 conidia ml-1. The Bb26 strain produced the highest sporulation, with a concentration of 1.52 x 108 conidia ml-1, and a sporulation of 77.9% of infected adults; followed by the MaCENGICAÑA strain (1.50 x108 conidia ml-1) and BbJLSV (1.76 x108 conidia ml-1) with 73.8 and 72.6% of sporulation, respectively. Sporulation of infected cadavers and inoculum concentration showed a positive correlation between the applied concentration and the production of conidia by flies (R2 = 0.91, Y = 1.63 + 0.14x), which suggested that when increasing the concentration of inoculum, the production of conidia tended to increase.
Palavras-chave : Microbial control; entomopathogen; Anastrepha obliqua; fruit flies.