Senior Research Scholar
Faculty Affiliate:
Apperson/Schal Medical Entomology, Dept. of Entomology,
Campus Box 7647, Dearstyne Entomology Building
3230 Ligon Road, N. C. State University
Raleigh, NC 27695-7647
Phone:
919.515.8882
Fax:
919.515.3748 Research:
Microbial Mediation of Mosquito Oviposition Semiochemicals
Our primary research goals are to identify the chemicals derived from bacterial metabolism that attract gravid Aedes mosquitoes and stimulate them to oviposit. Guided by behavioral bioassays, we optimized the bio-activity of infusions made from different plant leaf and showed that attractive odorants were produced through microbialmetabolic activity. Further to this, we demonstrated that bacteria-associated cues (carboxylic acids and methyl esters) were potent oviposition stimulants for Aedes aegypti. We have cultured bacteria from bio-active plant leaf infusions and we are currently using behavioral bioassays to screen bacterial species that mediate the oviposition responses.
Formulation of Bacterial Beads For Mosquito Oviposition Attractancy
In present research, we have shown that strong oviposition responses are elicited from gravid Aedes aegypti and Ae. albopictus females by a mix of bacterial species cultured from bio-active plant leaf infusions. When single species isolates are bioassayed, we determined that some bacterial species are highly attractive while other species are repellent. Currently, we are developing sustained release formulations of bio-active bacteria using alginate encapsulation techniques. When formulated in calcium alginate, bacteria are highly attractive to gravid mosquitoes. Alginate bacterial beads are a promising slow release formulation that can be used to attract gravid Aedes females to traps that are used for surveillance and control dengue virus vectors.
Molecular Microbial Ecology of Bacterial Populations in Mosquito Habitats
This part of our research is to understand how the structure and change of bacterial communities affects the occurrence of immatures Aedes mosquito species in containers habitats in residential landscapes. We are using both culture-dependent and culture-independent approaches. The culture-independent approach involves extractionof total DNA directly from mosquito container habitat samples, PCR amplificationof the 16S ribosomal DNA, and separation ofthe amplicons on a Denaturing Gradient Gel Electrophoresis (DGGE) and by Terminal Restriction Fragment Length Polymorphism (T-RFLP). Results of field experiments indicate that the bacterial communities composition was independent of the type of container and the spatial distribution of containers. In laboratory microcosms, bacterial species diversity and the abundance of bacteria have been found to be important determinants of the attraction of gravid females to experimental plant leaf infusions.
Publications in peer reviewed journals
- Ponnusamy L., K. Böröczky, D. M. Wesson, C. Schal and C. S. Apperson. 2011. Bacteria stimulate hatching of yellow fever mosquito eggs. PLoS ONE, 6(9): e24409.►Weblink
- Smith, M. P., L. Ponnusamy, J. Jiang, L. Abu Ayyash, A. L. Richards, and C. S. Apperson. 2010. Bacterial pathogens in ixodid ticks from a Piedmont county in North Carolina: Prevalence of rickettsial organisms. Vector Borne Zoon. Dis. 10:939-952.. ►Weblink
- Ponnusamy, L., N. Xu, K. Böröczky, D. M. Wesson, L. Abu Ayyash, C. Schal, and C. S. Apperson. 2010. Oviposition responses of the mosquitoes Aedes aegypti and Aedes albopictus to experimental plant infusions in laboratory bioassays. J. Chem. Ecol. 36:709-719. ►Weblink
- Ponnusamy, L., D. M. Wesson, C. Arellano, C. Schal, and C. S. Apperson. 2010. Species composition of bacterial communities influences attraction of mosquitoes to experimental plant infusions. Microb. Ecol. 59:158–173. ►Weblink
- Ponnusamy, L., N. Xu, D. M. Wesson, C. Schal, and C. S. Apperson. 2008. Identification of bacteria and bacteria-associated chemical cues that mediate oviposition site preferences by Aedes aegypti. PNAS 105:9262–9267. ►PDF
- Ponnusamy, L., N. Xu, G. Stav, D. M. Wesson, C. Schal, and C. S. Apperson. 2008. Diversity of bacterial communities in the container habitats of mosquitoes. Microb. Ecol. 56:593–603. ►PubMed
- Richards, S. L., L. Ponnusamy, T. R. Unnasch, H. K. Hassan, and C. S. Apperson. 2006. Host-feeding patterns of Aedes albopictus (Skuse) (Diptera: Culicidae) in relation to the availability of human and domestic animals in suburban landscapes of central North Carolina. J. Med. Entomol. 43:543-551. ►PDF
- Loganathan, P., and S. Nair. 2004. Swaminathania salitolerans gen. nov., sp. nov., a salt-tolerant, nitrogen-fixing andphosphate-solubilizing bacterium from wild rice (Porteresia coarctata Tateoka). Int. J.Syst. Evol. Microbiol. 54:1185-1190. ►PubMed
- Loganathan, P., and S. Nair. 2003. Crop-specific endophytic colonization by a novel, salt-tolerant, N-2-fixing and phosphate-solubilizing Gluconacetobacter sp from wild rice. Biotechnology Letters. 25:497-501.. ►PubMed
- Muthukumarasamy, R., G. Ravathi, and P. Loganathan. 2002. Effect of inorganic N on the population, in vitro colonization and morphology of Acetobacter diazotrophicus. Plant and Soil. 243:91-102. ►Weblink
- Saleena, L M., P. Loganathan, R. Sunitha, and S. Nair. 2001. Genetic diversity and relationship between Bradyrhizobium strains isolated blackgram and cowpea. Biol. Fertil. Soil. 34:276-281. ►Weblink
- Sunitha, R., P. Loganathan, L. M. Saleena, and S. Nair. 2001. Diversity of Pseudomonads isolated from three different plant rhizospheres. J. Appl. Microbiol. 91:742-749. PubMed
- Saleena, L. M., P. Loganathan, R. Sunitha, and S. Nair. 2001. Genetic diversity of Bradyrhizobium strains isolated from Arachis hypogaea. Canadian J. Microbiol. 47:118-122. ►PubMed
- Loganathan P., R. Sunitha, A. K. Paridha, and S. Nair. 1999. Isolation and characterization of two genetically distant groups of Acetobacter diazotrophicus from a new host plant Eleusine coracana L. J. Appl. Microbiol. 87:167-172. ►Weblink
- Palaniappan, S. P., P. Sudhi Sreedhar, P. Loganathan, and J. Thomas. 1997. Competitiveness of native Bradyrhizobium japonicum strains in two soil types. Biol. Fert. Soil. 25:279-284.. ►Weblink
Research in the News
2008 News
NCSU's Perspectives: Scientists discover chemical cues that stimulate egg laying by pregnant mosquitoes. ►Weblink
The New York Times: Not just any water will do for mosquitoes. ► Weblink
Science daily: Why mosquitoes select certain outdoor water containers for laying eggs and avoid others. ►Weblink
Science blogs: Bacterial smells have potential for trapping pregnant mosquitoes. ►Weblink
Chemistry World: Yellow fever mosquito takes chemical cues from bacteria. ►Weblink
Title in German: Wie Mücken fauliges Wasser riechen (Title to English translation. How mosquitoes smell foul water?), in Spektrum der Wissenschaft magazine, September 2008, page 11. ►Weblink
2007 News
Biofertiliser Newsletter: ►Weblink
India environment portal: Bacteria that reduces fertilser use ►Weblink
2004 News
The Hindu: Bacterium with salinity tolerance. ►Weblink
The Biome News: Plant growth promoting regulants and costal niche vol 5: No1 page 3
Down to Earth: Great little wonder. Feb. 15, 2004.
Professional Affiliation
Member: American society of Microbiology
North Carolina Branch of the American Society for Microbiology
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