23 research outputs found
Genotype characterization of the Haematobia Irritans (diptera: muscidae) from Brazil, Dominican Republic and Colombia based on randomly amplified polymorphic dna (rapd) analysis
Genetic divergence in mitochondrial DNA of Anopheles nuneztovari (Diptera: Culicidae) from Brazil and Colombia
In the present study, we have examined the variability in Anopheles nuneztovari mitochondrial DNA of three populations from the Brazilian Amazon and one from western Colombia (Sitronela), using four restriction endonucleases (BclI, ClaI, HindIII, SstI). The haplotype diversity (h) was slightly elevated in all populations (0.5000 to 0.6765), whereas the nucleotide diversity (Ï) was lower in the Sitronela population (0.0029) and higher in populations from the Brazilian Amazon (0.0056 to 0.0098). The degree of sequence divergence (ÎŽ) estimated within the Brazilian Amazon and that in Sitronela (0.0329 to 0.0371) suggests that these geographic populations of A. nuneztovari may eventually constitute separate species. The low sequence divergence values among the three Brazilian Amazon populations (0.0012 to 0.0031) indicate that these populations are genetically similar. These results are consistent with those recently reported for allozymes of these same populations
Molecular genetic variation of boll weevil populations in North America estimated with microsatellites: Implications for patterns of dispersal
Two Genetically Distinct Populations of Bobtail Squid, Euprymna scolopes, Exist on the Island of O'ahu
Population structure of the endemic Hawaiian bobtail squid, Euprymna
scolopes, was examined using both morphological and genetic data. Although
allozyme polymorphism was negligible, measurements of eggs, juveniles,
and adults, as well as genetic data sequences of mitochondrial cytochrome oxidase
I, demonstrated highly significant population structuring between two
populations found on the northeastern and southern coasts of the island of
O'ahu. These data suggest that extremely low levels of gene flow occur among
these populations. Population subdivision of marine shallow-water invertebrates
in Hawai'i is not expected based on earlier surveys, but may reflect a more
general pattern for organisms, both marine and terrestrial, that exhibit limited
dispersal. The subdivision also provides insight into the pathway through which
coevolution between E. scolopes and its internal symbiont, Vibrio fischeri, may
proceed
Population structure and colonization history of the olive fly, Bactrocera oleae (Diptera, Tephritidae)
The olive fly, Bactrocera oleae, is the major pest of olives in most commercial olive-growing regions worldwide. The species is abundant in the Mediterranean basin and has been introduced recently into California and Mexico, creating problems for quarantine protection and international trade. Here, we use nuclear microsatellite markers and mitochondrial sequences to examine the history of olive fly range expansion and colonization. Sampled populations span the current distribution of the olive fly worldwide, including South and Central Africa, Pakistan, Mediterranean Europe and Middle East, California, and Mexico. The Pakistani populations appear to be genetically well differentiated from the remaining populations, though rooting the origins of the species is problematic. Genetic similarity and assignment tests cluster the remaining populations into two genetic groups â Africa and a group including the Mediterranean basin and the American region. That Africa, and not the Mediterranean, is the origin of flies infesting cultivated olive is supported by the significantly greater genetic diversity at microsatellite loci in Africa relative to the Mediterranean area. The results also indicate that the recent invasion of olive flies in the American region most likely originated from the Mediterranean area