Reactive oxygen species production, induced by atmospheric modification, alter conidial quality of Beauveria bassiana.
OBJECTIVE
The aim of this study was to determine the relationship between reactive oxygen species (ROS) production and conidial infectivity in Beauveria bassiana.


RESULTS
Beauveria bassiana Bb 882.5 was cultured in solid-state culture (SSC) using rice under three oxygen conditions (21%, or pulses at 16 and 26%). Hydrophobicity was determined using exclusion phase assay. Bioassays with larvae or adults of Tenebrio molitor allowed the measurements of infectivity parameters. A fluorometric method was used for ROS quantification (superoxide and total peroxides). NADPH oxidase (NOX) activity was determined by specific inhibition. Conidial hydrophobicity decreased by O2 pulses. Mortality of larvae was only achieved with conidia harvested from cultures under 21% O2 ; whereas for adult insects, the infectivity parameters deteriorated in conidia obtained after pulses at 16 and 26% O2 . At day 7, ROS production increased after 16 and 26% O2 treatments. NOX activity induced ROS production at early stages of the culture.


CONCLUSIONS
Modification of atmospheric oxygen increases ROS production, reducing conidial quality and infectivity.


CONCLUSIONS
This is the first study in which conidial infectivity and ROS production in B. bassiana has been related, enhancing the knowledge of the effect of O2 pulses in B. bassiana.
División de Ingeniería Ambiental, Tecnológico de Estudios Superiores del Oriente del Estado de México, La Paz, Estado de México, Mexico.
D
D
Pérez-Guzmán
Centro Nacional de Referencia de Control Biológico, Tecomán, Colima, Mexico.
R
R
Montesinos-Matías
Instituto de Ciencias Agropecuarias, Universidad Autónoma del Estado de Hidalgo, Tulancingo, Hidalgo, Mexico.
O
O
Arce-Cervantes
Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, México D.F, Mexico.
L E
LE
Gómez-Quiroz
Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, México D.F, Mexico.
O
O
Loera
Instituto de Ciencias Agropecuarias, Universidad Autónoma del Estado de Hidalgo, Tulancingo, Hidalgo, Mexico.
P M
http://orcid.org/0000-0002-3151-8369
PM
Garza-López
D000818:Animals; D052982:Beauveria / Q000254:growth & development / Q000378:metabolism* / Q000472:pathogenicity; D001517:Coleoptera / Q000382:microbiology*; D007814:Larva / Q000382:microbiology; D010572:Pest Control, Biological; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013172:Spores, Fungal / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D014774:Virulence
D017382:Reactive Oxygen Species
Beauveria bassiana; infectivity; oxygen pulses; quality; reactive oxygen species