Entomopathogenic potential of Bacillus subtilis and B. amyloliquefaciens strains against Musca domestica L. under controlled conditions

MARÍA JULIA TORRES; VOYKO FLORES ROCHA; GABRIELA PETROSELLI,; ROSA ERRA-BALSELLS; REINALDO ROJAS VILLENA; CARINA AUDISIO, M.

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2022 p. 1 - 23

0013-8703

The house fly (Musca domestica L.) is a key pest in animal production areas; the resistance of this insect to chemical insecticides makes it necessary to develop new control alternatives. The aim of this work was to study the entomopathogenic activity of eight strains of Bacillus subtilis subsp. subtilis and two strains of B. amyloliquefaciens, isolated from different ecological niches, against the house fly. Cell suspension (CS) of each Bacillus strain and cell-free supernatant (CFS) and crude lipopeptide fraction (LF) of 7 mg/mL of B. amyloliquefaciens CBMDDrag3 and CBMDLO3 strains were evaluated. Different house fly cohorts, resulting from systematic crosses, were used for the bioassays. The eight strains of B. subtilis subsp. subtilis affected the survival of the larvae by 10 to 20%, whereas strains CBMDDrag3 and CBMDLO3 decreased the survival of these individuals by 30 and 50%, respectively. CBMDLO3 was the strain with the highest pupicidal activity, reducing the survival of these individuals by up to 50%. To evaluate the effect CBMDLO3 on the fertility of house fly females and longevity of individuals, adults from larvae fed CS, CFS and LF were used. The lowest number of eggs was laid by houseflies fed the CS and the CFS (144.3 and 128.0, respectively). On the other hand, the life cycle of females and males was only affected to a greater extent by LF (4 and 6 days shorter, respectively, than the control). The UV MALDI TOF analysis of CBMDLO3 LF identified several surfactin homologues. Results show the ability of B. amyloliquefaciens CBMDLO3 strain to reduce the survival of larvae and pupae of M. domestica and the fecundity of female adults, thus allowing cycles of inhibition of housefly development in laying hen farms. Therefore, B. amyloliquefaciens CBMDLO3 strain can make an important contribution to the continuous search of new biological control alternatives.