Genetic diversity in Brazilian populations of Anastrepha obliqua (Macquart) based on mtDNA.

Anastrepha obliqua (Macquart), the West Indian fruit fly, is the second most polyphagous species within the genus in Brazil and therefore one of the most economically important pest species. It infests an extensive range of hosts, at least 60 species. Anastrepha obliqua ranges from northern Mexico to southern Brazil also including the Caribbean Islands. Methods: We sequenced a fragment of the mitochondrial gene COI to estimate population structure and genetic diversity of A. obliqua geographic collections in Brazil. Results: A total of 153 specimens from the Amazon Forest, Atlantic Rainforest, Cerrado, and Caatinga were analyzed. A total of 20 haplotypes were found. The highest diversity levels were observed in collections from the Amazon Forest. AMOVA and Fst tests showed evidence of genetic structure allowing us to delineate two groups of A. obliqua populations. The Mantel tests were not significant indicating a weak correlation between genetic and geographic distances. Mismatch distributions and Neutrality Tests suggest that the Caatinga, Cerrado and Atlantic Forest populations have experienced a recent population expansion. Conclusion: Populations in the Amazon Forest showed high genetic diversity when compared to the other biomes and the demographic parameters indicated a recent expansion of A. obliqua in Brazil

Phylogenetic analysis of Anastrepha obliqua (Macquart) populations in Brazil.

Introduction: The West Indian fruit fly, Anastrepha obliqua, is a major pest of tropical fruits infesting a wide variety of hosts and in Brazil it is the second most frequent species in the genus. Molecular analyses have shown that A. obliqua does not represent a monophyletic group. This would suggest the need for more detailed studies about population structure. We sequenced a portion of genomic regions COI, ITS, Period and ND6 from A. obliqua gathered in Brazil. Methods: Forty two specimens were collected from fruits and traps from 25 geographic sites in eleven states in Brazil. Methods: DNA was isolated and a partial fragment of each genomic region was amplified by the Polymerase Chain Reaction, then sequenced. The sequences were concatenated in a sequence matrix. We performed partition analysis for each genomic region to choose the best evolution model. A Bayesian phylogenetic tree was constructed and analyses for population structure and demographics were estimated. Results: A fragment of 2,184 bp contained 78 variable sites e genetic distance of 2.8% between clades. A total of 33 haplotypes (designated H1-H33) were observed with haplotype diversity of 0.9884. We observed two clades. Clade I consisted of mostly Northeastern collections and clade II of collections from the Northern region. We saw that haplotypes recovered from individuals gathered in Pará and Amapá were present in both clades. Conclusion: Our results show high haplotype diversity and two clusters of A. obliqua in the phylogenetic tree with exclusive haplotypes in each region, which can have resulted from a decrease in gene flow between populations due to geographic distance

Invasive Phytophagous Pests Arising Through a Recent Tropical Evolutionary Radiation: The Bactrocera Dorsalis Complex of Fruit Flies

The Bactrocera dorsalis complex of tropical fruit flies (Diptera: Tephritidae: Dacinae) contains 75 described species, largely endemic to South-east Asia. Within the complex are a small number of polyphagous pests of international significance, including B. dorsalis s.s., B. papayae, B. carambolae and B. philippinensis. The majority of species within the complex were first described in 1994 and since then substantial research has been undertaken in developing morphological and molecular diagnostic techniques for their recognition. Such techniques can now resolve most taxa adequately. Genetic evidence suggests that the complex has evolved in only the last few million years and development of a phylogeny of the group is considered a high priority to provide a framework for future evolutionary and ecological studies. As model systems, mating studies on B. dorsalis s.s. and B. cacuminata have substantially advanced our understanding of insect use of plant-derived chemicals for mating, but such studies have not been applied to help resolve the limits of biological species within the complex. Although commonly regarded as major pests, we note that there is very little published evidence documenting economic losses caused by flies of the B. dorsalis complex. Quantification of economic losses caused by B. dorsalis complex species is urgently needed to prioritise research for quarantine and management. Although documented invaders, relatively little work has been done on the invasion biology of the complex and this is a further area warranting wor

Genetic structure and diversity in Brazilian populations of Anastrepha obliqua (Diptera: Tephritidae).

Anastrepha obliqua (Macquart), the West Indian fruit fly, is one of the most economically important pest species in the Neotropical region. It infests an extensive range of host plants that include over 60 species. The geographic range of A. obliqua is from northern Mexico to southern Brazil and includes the Caribbean Islands. Previous molecular studies have revealed significant genetic structure among populations. We used sequences from a fragment of the mitochondrial protein-coding gene cytochrome c oxidase I to estimate structure and genetic diversity of A. obliqua populations from Brazil. We analyzed a total of 153 specimens from the Amazon Forest, Atlantic Forest, Cerrado, and Caatinga biomes. Our study revealed weak genetic structure among the A. obliqua Brazilian populations sampled. Collections from the Amazon Forest had similar haplotype diversity compared to previously reported estimates for collections from the Caribbean and both populations are also closely related to each other, thus challenging the hypothesis that A. obliqua originated in the Caribbean and then moved to other regions of the Americas. Therefore, further evidence is necessary to draw a definite conclusion about the putative center of origin for A. obliqua. Additionally, we suggest a putative historical migration from the west to the east for the A. obliqua Brazilian populations, which could explain the high genetic diversity for this fly in the Amazon Forest and low genetic diversity in the other Brazilian biomes.Made available in DSpace on 2018-12-26T23:42:11Z (GMT). No. of bitstreams: 1 CPAFAP2018GeneticstructureanddiversityinBrazilian.pdf: 1706868 bytes, checksum: 2cd0279c2a6db5bf23e96fc5f914cd80 (MD5) Previous issue date: 2018-12-26bitstream/item/189327/1/CPAF-AP-2018-Genetic-structure-and-diversity-in-Brazilian.pd

Genetic Differentiation Between Sympatric Host Races Of The Apple Maggot Fly Rhagoletis-pomonella

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62806/1/336061a0.pd