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Biology subjects

Papadopoulos, N. T.

Publications and source records attributed to Papadopoulos, N. T..

6 recordsLinked to original sources

Mitogenome Diversity and Phylogenetic Insights of Aedes albopictus in Greece

The invasive mosquito species Aedes albopictus, commonly known as the Asian Tiger Mosquito, is a significant global health concern due to its role as a vector for diseases such as Dengue, Zika, and Chikungunya. In Greece, Ae. albopictus was first detected in 2005, with subsequent widespread establishment across the country. This study investigates the genetic diversity and phylogeography of Greek Ae. albopictus populations by analyzing mitochondrial cytochrome oxidase I (COI) gene sequences. A total of 488 female individuals were analyzed, revealing six haplotypes in samples collected from 2016 to 2018 using the LCO 1490 and HCO 2198 primer pair, including instances of identical haplotypes across years, while only one haplotype was consistently detected across all 2019 to 2022 samples using the UBC6 and UBC9 primer pair. These findings underscore the importance of molecular tools in understanding invasion dynamics and informing targeted surveillance and control measures. Further research is needed to assess additional worldwide populations and expand phylogeographic comparisons to elucidate global dispersal patterns.

genetics↗

Winter Survival of Culex pipiens f. pipiens Adults in Central Greece

Winter survival consists a major component of insect vectors life history in temperate environments that is directly related with early and later population growth next season with major consequences in the epidemiology of vectored diseases. The common European mosquito Culex pipiens is a major vector of the West Nile Virus (WNV) in Europe, including Greece. West Nile Virus outbreaks are frequently reported in Greece over the last 2 decades and Thessaly, Central Greece, is included in the affected areas. Here we report on overwintering trials conducted in three regions of Thessaly to investigate the overwintering dynamics of the subspecies of the Cx. pipiens complex, Cx. pipiens f. pipiens. Two overwintering experiments regarding adults of Cx. pipiens f. pipiens carried out in two coastal areas of Thessaly (Nea Anchialos and Volos) and an inland area (Kalamaki). Results demonstrated the successful overwintering of Cx. pipiens f. pipiens females, as well as the failure of males to survive in all three regions considered. Successful overwintering females were capable of initiating egg laying following a blood meal in spring onsetting the first summer generation. Nonetheless, mortality patterns differ between the coastal and the inland area as well as among different cohorts of adults.

ecology↗

Evidence that recent climatic changes have expanded the potential geographic range of the Mediterranean fruit fly

The species distributions migration poleward and into higher altitudes in a warming climate is especially concerning for economically important insect pest species, as their introduction can potentially occur in places previously considered unsuitable for year-round survival. We explore the expansion of the climatically suitable areas for a horticultural pest, the Mediterranean fruit fly (medfly) Ceratitis capitata (Diptera, Tephritidae), with an emphasis on Europe and California. We reviewed and refined a published CLIMEX model for C. capitata, taking into consideration new records in marginal locations, with a particular focus on Europe. To assess the model fit and to aid in interpreting the meaning of the new European distribution records, we used a time series climate dataset to explore the temporal patterns of climate suitability for C. capitata from 1970 to 2019. At selected bellwether sites in Europe, we found statistically significant trends in increasing climate suitability, as well as a substantial northward expansion in the modelled potential range. In California, we also found a significant trend of northward and altitudinal expansion of areas suitable for C. capitata establishment. These results provide further evidence of climate change impacts on species distributions and the need for innovative responses to increased invasion threats.

ecology↗

Daily Activity Profiles over the Lifespan of Female Medflies as Biomarkers of Aging and Longevity

The relationship between the early age activity of Mediterranean fruit flies or other fruit flies and their lifespan has not been much studied, in contrast to the connections between lifespan and diet, sexual signaling and reproduction. The objective of this study is to assess intraday and day-to-day activity profiles of female Mediterranean fruit flies and their role as biomarker of longevity as well as to explore the relationships between these activity profiles, diet and age-at-death throughout the lifespan. Three distinct patterns of activity variations in early age activity profiles can be distinguished. A low-caloric diet is associated with a delayed activity peak, while a high-caloric diet is linked with an earlier activity peak. We find that age-at-death of individual medflies is connected to their activity profiles in early life. An increased risk of mortality is associated with increased activity in early age, as well as with a higher contrast between daytime and nighttime activity. Conversely, medflies are more likely to have a longer lifespan when they are fed a medium caloric diet and when their daily activity is more evenly distributed across the early age span and between daytime and nighttime. The before-death activity profile of medflies displays two characteristic before-death patterns, where one pattern is characterized by slowly declining daily activity and the other by a sudden decline in activity that is followed by death.

bioinformatics↗

Laboratory rearing alters activity and sleep patterns in the olive fruit fly

Olive fruit flies, Bactrocera oleae (Diptera: Tephritidae) that are laboratory reared in artificial diet are essential for the genetic control techniques for this pest. However, the colonys laboratory adaptation can affect their quality. We used the Locomotor Activity Monitor (LAM25, Trikinetics, MA, USA) to track the activity and sleep patterns of adult olive fruit flies reared as immatures in olives (F2-F3 generation) and in artificial diet (>300 generations). Counts of beam breaks caused by the adult fly activity were used as an estimation of its locomotor activity levels during the light and dark period. A longer than five minutes period of adults inactivity during the dark period was considered as one sleep episode. Activity levels and sleep parameters were found to be dependent on sex, mating status and rearing history. In virgin flies reared in olives, males were more active than females and increased their locomotor activity towards the end of the light period. Mating decreased the locomotor activity levels of males, but not of females olive-reared flies. Laboratory flies reared in artificial diet had lower locomotor activity levels during the light period and more sleep episodes of shorter duration compared to flies reared in olives. We describe the diurnal locomotor activity patterns of B. oleae adults reared in olive fruits and in artificial diet. We discuss how locomotor activity and sleep pattern differences may affect the laboratory flies ability to compete with wild males in the field.

animal behavior and cognition↗

Wolbachia pipientis associated to tephritid fruit fly pests: from basic research to applications

Members of the true fruit flies (family Tephritidae) are among the most serious agricultural pests worldwide, whose control and management demands large and costly international efforts. The need for cost-effective and environmentally-friendly integrated pest management (IPM) has led to the development and implementation of autocidal control strategies. Autocidal approaches include the widely used sterile insect technique (SIT) and the incompatible insect technique (IIT). IIT relies on maternally transmitted bacteria (namely Wolbachia), to cause a conditional sterility in crosses between released mass-reared Wolbachia-infected males and wild females, which are either uninfected or infected with a different Wolbachia strain (i.e., cytoplasmic incompatibility; CI). Herein, we review the current state of knowledge on Wolbachia-tephritid interactions including infection prevalence in wild populations, phenotypic consequences, and their impact on life history traits. Numerous pest tephritid species are reported to harbor Wolbachia infections, with a subset exhibiting high prevalence. The phenotypic effects of Wolbachia have been assessed in very few tephritid species, due in part to the difficulty of manipulating Wolbachia infection (removal or transinfection). Based on recent methodological advances (high-throughput DNA sequencing) and a breakthrough concerning the mechanistic basis of CI, we suggest research avenues that could accelerate generation of necessary knowledge for the potential use of Wolbachia-based IIT in area-wide integrated pest management (AW-IPM) strategies for the population control of tephritid pests.

ecology↗