Exploration of culturable bacterial associates of aphids and their interactions with entomopathogens

• Published in: Archives of microbiology Vol. 206; no. 3; p. 96
• Main Authors: Kumar, M. P. Shireesh, Keerthana, Alagesan, Priya, Singh, Satish Kumar, Rai, Dinesh, Jaiswal, Aman, Reddy, Morthala Shankara Sai
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-03-2024; Springer Nature B.V
• Subjects: Akanthomyces lecanii; Animals; Aphids; Bacillaceae; Bacillus; Bacteria; Bacteria - genetics; Biochemistry; Biomedical and Life Sciences; Biotechnology; Cell Biology; Cell lines; Ecology; Firmicutes; Germfree; Growth media; Insects; Life Sciences; Lipaphis erysimi; Metarhizium anisopliae; Microbial Ecology; Microbiology; Microflora; Original Paper; Pathogens; Pest control; Pests; Pure culture; Rhopalosiphum maidis; Rhopalosiphum padi; Schizaphis graminum; Sitobion avenae; Culturable bacteria; Aphid; Bacterial load; Endosymbionts; Entomopathogens
• ISSN: 0302-8933; 1432-072X
• DOI: 10.1007/s00203-024-03830-x

Aphids shelter several bacteria that benefit them in various ways. The associates having an obligatory relationship are non-culturable, while a few of facultative associates are culturable in insect cell lines, axenic media or standard microbiology media. In the present investigation, isolation, and characterization of the culturable bacterial associates of various aphid species, viz.,
Rhopalosiphum maidis
,
Rhopalosiphum padi
,
Sitobion avenae
,
Schizaphis graminum
, and
Lipaphis erysimi pseudobrassicae
were carried out. A total of 42 isolates were isolated using different growth media, followed by their morphological, biochemical, and molecular characterization. The isolated culturable bacterial associates were found to belong to the genera
Acinetobacter
,
Bacillus
,
Brevundimonas
,
Cytobacillus
,
Fictibacillus
,
Planococcus
,
Priestia
,
Pseudomonas
,
Staphylococcus
,
Sutcliffiella
, and
Tumebacillus
which were grouped under seven families of four different orders of phyla Bacillota (Firmicutes) and Pseudomonata (Proteobacteria). Symbiont–entomopathogen interaction study was also conducted, in which the quantification of colony forming units of culturable bacterial associates of entomopathogenic fungal-treated aphids led us to the assumption that the bacterial load in aphid body can be altered by the application of entomopathogens. Whereas, the mycelial growth of entomopathogens
Akanthomyces lecanii
and
Metarhizium anisopliae
was found uninhibited by the bacterial associates obtained from
Sitobion avenae
and
Rhopalosiphum padi
. Analyzing persistent aphid microflora and their interactions with entomopathogens enhances our understanding of aphid resistance. It also fosters the development of innovative solutions for agricultural pest management, highlighting the intricate dynamics of symbiotic relationships in pest management strategies.