Selection of improved Beauveria bassiana (Bals.) Vuill. strains based on 2-deoxy-D-glucose resistance and physiological analysis.
A series of 2-deoxy-D-glucose resistant mutants was obtained from wild type Beauveria bassiana 88 (Bb 88) by UV irradiation. Five mutants were characterized on Sabouraud Dextrose Agar and Chitin Agar for both radial extension rate (V(r)) and specific growth rate (micro). These values were obtained after adjusting morphometric data to a mathematical model used for filamentous fungi. Additionally, the protease and lipase potency index, conidial size, viability, and production levels were analyzed. The highest values for those physiological measurements were obtained by mutant 882.5 which, relative to Bb 88, showed a 30% reduction in half-life (LT(50)) on Sphenarium purpurascens, 70% on Acheta domesticus, and 71% on Tenebrio molitor larvae and adults. The half lethal concentration (LC(50)) on T. molitor larvae was 2.8 x 10(5)conidia/mL (con/mL) and 1.5 x 10(6)con/mL, respectively, for mutant 882.5 and Bb 88. This demonstrates that mutant 882.5 is more virulent, with up to an 80% reduction in LC(50). This work provides a convenient method for improving strains to be used in biocontrol as a suitable alternative to transgenic constructs.
Robledo-Monterrubio
M
M
Area de Biología, Universidad Autónoma Chapingo, Km 38.5 Carretera México-Texcoco, CP, Mexico.
Alatorre-Rosas
R
R
Viniegra-González
G
G
Loera
O
O
D000818:Animals; D052982:Beauveria / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity*; D001517:Coleoptera / Q000254:growth & development / Q000382:microbiology; D003847:Deoxyglucose / Q000494:pharmacology*; D025141:Drug Resistance, Fungal; D006110:Grasshoppers / Q000254:growth & development / Q000382:microbiology; D006135:Gryllidae / Q000254:growth & development / Q000382:microbiology; D007814:Larva / Q000382:microbiology; D009154:Mutation; D010572:Pest Control, Biological
D003847:Deoxyglucose