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Item Diversity of midgut symbiotic bacteria in Aedes mosquito genera: A meta-analysis(Faculty of Science, University of Kelaniya Sri Lanka, 2022) Kumari, J. Y.; Amarasinghe, L. D.; Udayanga, N. W. B. A. L.; Ranasinghe, H. A. K.The gut bacterial composition of mosquitos has the capability of altering mosquito pathogen transmission through numerous mechanisms, which is useful in novel transmission control strategies. Therefore, understanding the diversity of gut bacteria in different mosquito genera is highly important. The present analysis was carried out to evaluate the variations in gut-bacteria in field-caught Aedes adult mosquitos from different geographical locations. A literature survey was conducted to identify quantitative data related to the midgut bacterial abundance in Aedes, using standard search terms and keywords. The collected data were arranged at the bacterial class level and were subjected to a square-root transformation. A resemblance matrix was constructed based on the Bray-Curtis resemblance. Cluster analysis followed by the Analysis of Similarities (ANOSIM) and Distance based Redundancy Analysis (dbRDA) were used for data analysis. Gut bacterial abundance from six different countries; Netherlands, USA, Sri Lanka, India, Brazil, and Panama, were used in the study. A total of 12 bacterial classes, were recorded and bacterial classes of Alphaproteobacteria and Gammaproteobacteria accounted for the highest abundance in Aedes mosquitoes from most of the countries. Interestingly, Aedes mosquitoes from Brazil, India and Sri Lanka, did not report the abundance of Alphaproteobacteria in their gut contents. Based on the Bray-Curtis similarity-based cluster analysis, four major clusters were identified at a similarity level of 48.9%, based on the overall abundance of bacterial classes. Aedes mosquitoes of Sri Lanka and India formed one cluster, sharing a similarity of 81.6%, while Brazil and Panama formed another cluster. Meanwhile, Aedes mosquitoes from Netherland and USA formed two separate clusters. The statistical significance of aforementioned clustering status was further verified by the Analysis of Similarities (ANOSIM), which reported a Global R value of 0.96. The clustering status suggested by the cluster analysis was further verified by the findings of the dbRDA. As indicated by the loadings of the dbRDA axes, the abundance of Gammaproteobacteria and Bacilli bacterial classes were found to be responsible for the similarity between gut bacterial diversity in Aedes mosquitoes from India and Sri Lanka. Further studies on the gut-microbial diversity of Aedes mosquitoes are recommended to support the implementation of novel vector control strategies in Sri Lanka.Item First report of Culex (Lophoceraomyia) cinctellus in Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2022) Rangana, U. L. P.; Kumarasinghe, K. G. D. S. G. S.; Jayasinghe, H. P. N. T.; Refai, F. W.; Udayanga, N. W. B. A. L.; Ranathunge, R. M. T. B.Disease epidemics caused by mosquito vectors have been a significant challenge faced by the health sector of Sri Lanka. Routine entomological surveillance is practised as a key approach in monitoring the population dynamics of mosquito vectors, which is vital for epidemic management. A recent preliminary surveillance conducted in Banduragoda Public Health Inspector (PHI) in Mirigama Medical Officer of Health (MOH) area has reported the presence of Culex (Lophoceraomyia) cinctellus, for the first time in Sri Lanka. Therefore, the current study was conducted to validate the presence of Cx. cinctellus, based on morphological and molecular evidence. Larval and adult surveillances were conducted from October 2019 to April 2020 at fortnight intervals in the Banduragoda Public Health Inspector (PHI) area. Standard siphoning methods were used in larval surveillance, while Cattle Baited Traps (CBT), Gravid Traps (GT), Light Traps (LT), Bird-Baited Traps (BBT), Dog Baited Traps (DBT) and diurnal human landing collections were used for adult surveillance. The collected specimens were transported to the Entomology Laboratory of the Medical Research Institute (MRI). The immature larvae were reared up to fourth instar stage. Adults and reared larvae were identified to the species level using standard morphological keys. Further, DNA extracted from the head, and thoracic regions of the reared mosquitoes were sequenced. Subsequently, the sequences were analysed for sequence identity using NCBI BLAST analysis and Geneious Trial (version 7.1.3). Adults of Cx. cinctellus were reported from BBT and in human baited collections. Morphological features such as well-developed pulvilli, wing with vein 1A ending before the apex of cross vein mcu, basal transverse pale bands in abdominal terga and two labial basal setae in proboscis were identified as unique features of Cx. cinctellus. Females of Cx. cinctellus reported a mean thoracic length of 0.58 ± 0.02 mm, thoracic width of 0.63±0.02 mm. The average abdominal length and width were 2.15±0.03 mm and 0.61±0.01 mm respectively, along with a wing length of 2.91±0.02 mm. The results of the molecular analysis further confirmed the morphological identification. This finding warrants the importance of strengthening routine entomological surveillance activities further to study the dispersal and population dynamics of Cx. cinctellus in Sri Lanka.Item Use of morphological and molecular methods in identification of Asian bush mosquito, Aedes japonicus (Theobald, 1901), in Sri Lanka(Faculty of Science, University of Kelaniya Sri Lanka, 2022) Wickramasinghe, T. K. C.; Udayanga, N. W. B. A. L.; Manamperi, A. A. P. S.; Hapugoda, M. D.; Karunarathna, K. H. T.; Ranathunge, R. M. T. B.Conducting routine entomological surveillance to identify new vectors and changes in the distribution patterns of vectors is important for the management of mosquito borne diseases in Sri Lanka. A recent preliminary entomological survey reported the presence of Aedes japonicus in Sri Lanka in March 2021. Therefore, the current study was conducted to validate the presence of Ae. japonicus in Sri Lanka, based on morphological and molecular evidence. The search for Ae. japonicus breeding sites and developmental stages using standard siphoning methods were conducted in Kosgama and Pallekanugala areas located in the Districts of Colombo and Kegalle, respectively, from May to December 2021. Collected immature stages were reared up to the fourth instar stage or adult, and specimens were identified to species level using standard morphological keys. Further, DNA was extracted from the head, and thoracic regions of the reared mosquitoes and Polymerase Chain Reaction (PCR) was performed. The amplified products were sequenced at a commercial facility (Macrogen Inc. co. Ltd., Seoul, Korea). Subsequently, the sequences were analysed for sequence identity using NCBI BLAST analysis and Geneious Trial (version 7.1.3). Based on the morphological characteristics, larvae of Ae. japonicus were identified from both study areas. Ae. japonicus was reported only from natural breeding containers such as bamboo plants and tree holes in both study areas. The molecular analysis further confirmed the morphological identification. Further, newly reported Ae. japonicus population denoted a close relationship to the Austrian/Slovenian population. Ae. japonicus is well adapted to temperate climates and has been reported to possess a strong tendency to expand and colonies into new territories, which is facilitated by human-mediated, passive transportation. According to Unweighted Pair Group Method with Arithmetic Mean (UPGMA) based hierarchical cluster analysis, newly discovered Ae. japonicus denoted strong affinity to a previously detected Ae. japonicus strain in Eastern Austria/Slovenia. The dispersal and population dynamics of Ae. japonicus should be thoroughly surveyed in Sri Lanka, as this species is a potential vector of Japanese Encephalitis.Item Evaluation of the water tolerance ability of Alysicarpus vaginalis L. as a ground cover(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Subashini, J. K. W. N.; Abeywickrama, N. C.; Yakandawala, K.; Udayanga, N. W. B. A. L.