Title
Control of Aedes aegypti (Diptera: Culicidae) by means of biofilm-forming actinobacteria
Other title
CONTROL DE Aedes aegypti (DIPTERA: CULICIDAE) MEDIANTE ACTINOBACTERIAS FORMADORAS DE BIOPELÍCULAS
Date Issued
01 September 2021
Access level
open access
Resource Type
journal article
Publisher(s)
Universidad Nacional de Colombia
Abstract
Actinobacteria include several ubiquitous members involved in the synthesis of multipurpose bioactive compounds strictly derived from the genus Streptomyces. Nevertheless, new bacterial consortia based on non-streptomycetes actinobacteria are needed to be explored in order to avoid rediscoveries and minimize the development of insecticide resistance in Aedes aegypti. In accordance with the use of eco-friendly bioagents, in this study biofilm-forming actinobacteria were characterized on the basis of assessment their growth dynamics, larvicidal mortality and sublethal effects. Actinobacteria identification, biofilm growth and larvicidal bioactivities were performed by employing bacterial cultures, photomicrograph-based image analysis and bioassays. Bacterial morphotypes belong to Pseudonocardiaceae (PsA1TA) and Corynebacteriaceae (CoA2CA), which showed a distinctly substrate-dependent growth. PsA1TA microcolonies were randomly distributed on abdominal and thoracic membranous epicuticle. Afterwards, the thickness of mono-and bi-layered biofilms were increased fourfold the larval thoracoabdominal width (infectious breadth, 1010 µm-1036 µm). In contrast, cephalic and anal sclerotized structures were radially encased by CoA2CA biofilms and increased threefold the size of both structures (infectious breadth, 1820-2030 µm y 1650-1860 µm, respectively). Although biofilms caused dissimilar mortality rates on the four larval instars, PsA1TA exerted highest larvicidal activity and virulence on second instar larvae (58 %-96 hours, LT50: 3.4 days) y CoA2CA on fourth instar larvae (85 %-96 hours, LT50: 2.5 days). CoA2CA also induced incomplete release of pharate individuals as well as buckled protruding tarsi in newly emergent adults, whilst larval cadavers were overwhelmingly encased within massive biofilm aggregates. Biofilm-forming actinobacteria performed biolarvicidal activity and sublethal responses in A. aegypti.
Start page
423
End page
438
Volume
26
Issue
3
Language
Spanish
OCDE Knowledge area
Otros temas de Biología
Scopus EID
2-s2.0-85123782537
Source
Acta Biologica Colombiana
ISSN of the container
0120548X
Sources of information: Directorio de Producción Científica Scopus