Influence de la température sur la croissance in vitro d'hyphomycètes entomopathogènes

Abstract

Résumé — L'influence de la température sur la croissance in vitro des principales espèces d'hyphomycètes entomopathogènes a été étudiée avec 31 isolats fongiques : 3 souches de Beauveria bassiana (Balsamo) Vuillemin, 3 souches de B brongniartii (= tenella) (Saccardo) Petch, 8

A novel method to optimize culture conditions for biomass and sporulation of the entomopathogenic fungus Beauveria Bassiana IBC1201

“…Therefore, the combined effect of high temperature and low water availability on vegetative growth of B. bassiana was studied. Variations in isolate response to high temperature and low water availability conditions were observed, as anticipated from previous reports (11,12,13). Hallsworth and Magan (16), and Sivasankaran et al (44) reported that B. bassiana isolates require high levels of water activity in the surrounding medium for germination.…”

“…bassiana has been studied (7,12,13,22,44). A temperature of 25°C was reported optimum for B. bassiana by Fargues et al…”

“…We expect that the response of this isolate to nutrition and environment could differ from that of other isolates because B. bassiana is genetically variable; for example, isolates differed in their response to high temperature and low water availability (11,12,13). The specific objectives of this study were to quantify production of biomass and spores by B. bassiana IBC1201 as affected by combinations of carbon and nitrogen sources, carbon concentration, C:N ratios, and environment (pH, water potential, temperature, and light).…”

Detection of entomopathogenic fungi in peridomestic triatomine-infested areas in central Brazil and fungal activity against Triatoma infestans (Klug) (Hemiptera: Reduviidae)

“…Both species were isolated from substrates collected in typical vector habitats, and all isolates proved to be highly active against T. infestans at favorable conditions of moisture. M. anisopliae is considered a mildly thermophilic species in comparison to B. bassiana (Fargues et al 1992, Ouedraogo et al 1997, and the higher incidence of this pathogen in this study may be related to the tropical climate in Central Brazil.…”

“…Composition of the substrate or the diversity and number of microorganisms may affect survival and development of entomopathogenic fungi. Extreme temperature conditions, especially those exceeding 35ºC, may injure or kill fungi (Fargues et al 1992, Ouedraogo et al 1997, Luz & Fargues 1997. Such elevated temperatures can easily be achieved in closed rooms such as poultry houses, barns or other unventilated spaces after prolonged exposure to sunlight.…”