In vivo interactions of entomopathogenic fungi, Beauveria spp. and Metarhizium anisopliae with selected opportunistic soil fungi of sugarcane ecosystem.

In the present study, the interactions of entomopathogenic fungi viz., Beauveria bassiana, Beauveria brongniartii and Metarhizium anisopliae among themselves and three other opportunistic soil fungi from the sugarcane ecosystem namely, Fusarium saachari, Aspergillus sp. and Penecillium sp. were assayed in vivo against Galleria mellonella larvae. The tested fungi were co-applied on IV instar G. mellonella @ 1x 107 ml-1, in combinations of two, at the interval of 24 hrs either preceding or succeeding each other to assess their efficacy and sporulation rates. Results showed that often mortality rates did not correspond to the spore harvest of the mortality agent and presence of other fungus may be antagonistic. The efficacy of B. bassiana (90%) and B. brongniartii (100%) was not enhanced further but was negatively affected in most combinations with other fungi. In case of M. anisopliae compatibility was higher, resulting in higher mortality by application of B. bassiana before (100%) or after (83.3%) M. anisopliae than when it was applied alone (70%). During sporulation, B. bassiana faced the most intense competition from M. anisopliae (2.75x106 larva-1) and enhancement due to F. sacchari irrespective of sequence of application. In case of B. brongniartii, sporulation was lowest in the combination of B. brongniartii preceding M. anisopliae (1.83 x106 larva-1) and B. brongniartii succeeding B. bassiana (1.58x106 larva-1). Of all fungi tested, except F. sacchari (65.33 x 106 larva-1) all the other species affected sporulation of M. ansiopliae with the least in treatment of B. bassiana application following M. anisopliae. Similar kind of interaction was observed during sporulation of soil fungi when combined with entomopathogenic fungi, though individually they could not cause mortality of larvae.

Efecto de Beauveria bassiana y Beauveria brongniartii en el control de moscas (Musca domestica) en condiciones de laboratorio y en galpones avícolas / Effect of Beauveria bassiana and Beauveria brongniartii for the house fly (Musca domestica) control on laboratory and poultry sheds conditions

Se realizó un experimento en el estado Trujillo, Venezuela con el objetivo de evaluar en condiciones de laboratorio y en galpones avícolas la patogenicidad de Beauveria brongniartii (cepaLF-05) y Beauveria bassiana (LF-08) sobre Musca domestica. Se determinó que a la dosis de 1,2 x107 conidiosporas/mL para B. brongniartii y B. bassiana los tiempos letales (TL50 y TL95) fueron5 y 9 días y 5 y 6 días, respectivamente. En condiciones de campo las esporas de B. brongniartiiy B. bassiana fueron nebulizadas en el interior de galpones de cría de pollos con una densidad de 7 pollos/m2, a dosis de 9 x 107 conidias/mL en 15L de agua por cada 1200 m2; el porcentaje de reducción poblacional después de nebulizar una vez por semana, durante tres semanas, fue de 13,99 y 100% para B. brongniartii y -35, 91 y 100% para B. bassiana

An experiment was carried out in Trujillostate, Venezuela, in laboratory and poultry shedsconditions in order to study the Beauveria brongniartii(strain: LF-05) and Beauveria bassiana (strain: LF-08) pathogenicity in Musca domestica. With 1.2 x 107conidiospores/mL the lethal times (TL50 and TL95)were 5 and 9, and 5 and 6 days, respectively. In fieldconditions spores of B. brongniartii and B. bassianawere applied inside the poultry sheds (7 chickens/m2)with a dose of 9 x 107 conidia/mL in 15L of water foreach 1200 m2, the percentage of population reductionwere induced after vaporized once a week for threeweeks in 13.99 and 100% for B. brongniartii; and -35,91 and 100% for B. bassiana