ABSTRACT
Beauveria bassiana Vuillemin and Metarhizium anisopliae (Metschnikoff) Sorokin are fungi with potential for controlling Musca domestica L. However, the impact on this dipteral may vary depending on the fungal isolates and the methodology used. This study evaluated the pathogenicity of direct application and horizontal transmission of B. bassiana (CG240) and M. anisopliae (CG34) on adult M. domestica individuals. The impact of B. bassiana and M. anisopliae on M. domestica was evaluated at the concentrations 2 × 10(4), 2 × 10(5), 2 × 10(6), and 2 × 10(7) conidia/ml. Horizontal transmission was also estimated between sexes at different infection periods of the vector insect. The mortality of adult M. domestica individuals directly infected with B. bassiana was above 90%, and the mortality of those infected with M. anisopliae ranged from 25.50 to 97.78%. Horizontal transmission of B. bassiana caused the death of 100% of individuals, in turn, that of M. anisopliae killed 55% of male and 100% of female individuals. Horizontal transmission of fungi was negatively influenced by time. This study shows the potential of these fungi for controlling M. domestica, both with the direct implementation strategy and horizontal transmission. However, field studies are needed to evaluate the capacity to decrease the M. domestica population using these alternatives.
Subject(s)
Beauveria/physiology , Houseflies/microbiology , Metarhizium/physiology , Pest Control, Biological , Animals , Female , Male , Spores, Fungal/physiologyABSTRACT
O objetivo do trabalho foi estimar as exigências térmicas e o número de gerações, mensal e anual, de Spalangia endius em pupas de Musca domestica em quatro temperaturas constantes. O período de desenvolvimento de S. endius foi obtido por meio de 100 pupas de M. domestica, com idade entre 24-48 horas, expostas por 24 horas aos parasitoides, para cada temperatura, sendo feitas três réplicas. Após esse período, as pupas foram individualizadas em tubos de ensaio e acondicionadas em estufa B.O.D., nas temperaturas de 20, 25, 30 e 35° C com umidade ≥ 70% e fotofase (12h), onde foram observadas diariamente até a emergência dos parasitoides. A temperatura influenciou a duração do período de desenvolvimento de S. endius. O menor período de ovo a adulto foi a 35° C (16,84 dias) e a maior porcentagem de emergência foi a 20° C (37%). A temperatura base encontrada foi de 11,27° C, com uma constante térmica de 390,96 graus-dia (GD). O período de desenvolvimento foi inversamente proporcional à temperatura e a média de gerações por ano foi de 7,24, variando de 7,03 a 7,48.
The aim of this work was to estimate the thermal requirements and the number of generations, monthly and annually, of Spalangia endius in pupae of Musca domestica at four constant temperatures. The development period of S. endius was obtained through 100 pupae of M. domestica, with ages between 24-48 hours, exposed for 24 hour to the parasitoids for each temperature, with three replicas. After this period the pupae were individualized in assay tubes and placed in B.O.D. with temperatures of 20, 25, 30 and 35º C and humidity ≥ 70% and photophase (12h), where they were observed daily until the emergence of the parasitoids. The temperature influenced the duration of the development period of S. endius. The shorter period form egg to adult was at 35º C (16.84 days) and the higher percentage of emergence was at 20º C (37%). The basis temperature was 11.27ºC with a thermal constant of 390.96 degrees-day (DD). The development period was inversely proportional to temperature and the medium of generations per year was 7.24, varying from 7.03 to 7.48.
