Genetic diversity and geographic distribution ofBemisia tabaci(Gennadius) (Hemiptera: Aleyrodidae) genotypes associated with cassava in East Africa

Abstract Background The need for enhancing the productivity of fisheries in Africa triggered the introduction of non-native fish, causing dramatic changes to local species. In East Africa, the extensive translocation of Nile tilapia (Oreochromis niloticus) is one of the major factors in this respect. Using 40 microsatellite loci with SSR-GBS techniques, we amplified a total of 664 individuals to investigate the genetic structure of O. niloticus from East Africa in comparison to Ethiopian and Burkina Faso populations. Results All three African regions were characterized by independent gene-pools, however, the Ethiopian population from lake Tana showed to be more divergent than expected suggesting that it might be a different species. In East Africa, the genetic structure was congruent with both geographical location and anthropogenic activities. O. niloticus from Lake Turkana (Kenya) was isolated, while in Uganda, despite populations being rather similar to each other, two main natural catchments were able to be defined. We show that these two groups contributed to the gene-pool of different non-native populations. Moreover, admixture and possible hybridization with other tilapiine species may have contributed to the genetic divergence found in some populations such as Lake Victoria. We detected other factors that might be affecting Nile tilapia genetic variation. For example, most of the populations have gone through a reduction of genetic diversity, which can be a consequence of bottleneck caused by overfishing, genetic erosion due to fragmentation or founder effect resulting from stoking activities. Conclusions The anthropogenic activities particularly in the East African O. niloticus translocations, promoted admixture and contact with the native congenerics which may contribute to outbreeding depression and hence compromising the sustainability of the species in the region.

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Genetic Diversity and Geographic Distribution of Mus musculus Subspecies Based on the Polymorphism of Mitochondrial DNA

Genetics In Wild Mice ◽

10.1159/000424145 ◽

2015 ◽

pp. 25-40 ◽

Cited By ~ 9

Author(s):

Hiromichi Yonekawa ◽

Sumiyo Takahama ◽

Osamu Gotoh ◽

Nobumoto Miyashita ◽

Kazuo Moriwaki

Keyword(s):

Genetic Diversity ◽

Mitochondrial Dna ◽

Geographic Distribution ◽

Mus Musculus

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The Mitochondrial Genetic Diversity of the Olive Field Mouse Abrothrix olivacea (Cricetidae; Abrotrichini) is Latitudinally Structured Across Its Geographic Distribution

Journal of Mammalian Evolution ◽

10.1007/s10914-021-09582-5 ◽

2022 ◽

Author(s):

Marcial Quiroga-Carmona ◽

Carolina Abud ◽

Enrique P. Lessa ◽

Guillermo D’Elía

Keyword(s):

Genetic Diversity ◽

Geographic Distribution ◽

Field Mouse

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An Ecological Study of Lactococci Isolated from Raw Milk in the Camembert Cheese Registered Designation of Origin Area

Applied and Environmental Microbiology ◽

10.1128/aem.64.12.4729-4735.1998 ◽

1998 ◽

Vol 64 (12) ◽

pp. 4729-4735 ◽

Cited By ~ 90

Author(s):

D. Corroler ◽

I. Mangin ◽

N. Desmasures ◽

M. Gueguen

Keyword(s):

Genetic Diversity ◽

Geographic Distribution ◽

Ecological Study ◽

Raw Milk ◽

Randomly Amplified Polymorphic Dna ◽

Histidine Biosynthesis ◽

Subspecies Level ◽

Camembert Cheese ◽

Reference Strains ◽

Origin Area

ABSTRACT The genetic diversity of lactococci isolated from raw milk in the Camembert cheese Registered Designation of Origin area was studied. Two seasonal samples (winter and summer) of raw milk were obtained from six farms in two areas (Bessin and Bocage Falaisien) of Normandy. All of the strains analyzed had a Lactococcus lactis subsp.lactis phenotype, whereas the randomly amplified polymorphic DNA (RAPD) technique genotypically identified the strains as members of L. lactis subsp. lactis orL. lactis subsp. cremoris. The genotypes were confirmed by performing standard PCR with primers corresponding to a region of the histidine biosynthesis operon. The geographic distribution of each subspecies of L. lactis was determined; 80% of the Bocage Falaisien strains were members ofL. lactis subsp. lactis, and 30.5% of the Bessin strains were members of L. lactis subsp.lactis. A dendrogram was produced from a computer analysis of the RAPD profiles in order to evaluate the diversity of the lactococci below the subspecies level. The coefficient of similarity for 117 of the 139 strains identified as members of L. lactis subsp.cremoris was as high as 66%. The L. lactis subsp. lactis strains were more heterogeneous and formed 10 separate clusters (the level of similarity among the clusters was 18%). Reference strains of L. lactissubsp. lactis fell into 2 of these 10 clusters, demonstrating that lactococcal isolates are clearly different. As determined by the RAPD profiles, some L. lactis subsp.lactis strains were specific to the farms from which they originated and were recovered throughout the year (in both summer and winter). Therefore, the typicality of L. lactissubsp. lactis strains was linked to the farm of origin rather than the area. These findings emphasize the significance of designation of origin and the specificity of “Camembert de Normandie” cheese.

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Genetic Diversity and Geographic Distribution of Genetically Distinct Rabies Viruses in the Philippines

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0002144 ◽

2013 ◽

Vol 7 (4) ◽

pp. e2144 ◽

Cited By ~ 13

Author(s):

Mariko Saito ◽

Hitoshi Oshitani ◽

Jun Ryan C. Orbina ◽

Kentaro Tohma ◽

Alice S. de Guzman ◽

...

Keyword(s):

Genetic Diversity ◽

Geographic Distribution ◽

The Philippines

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A new species of Grandjeana (Acari: Trombiculidae) from heart-nosed bat (Chiroptera: Megadermatidae) in Ethiopia (Africa) with notes to biogeography of this genus

Biologia ◽

10.1515/biolog-2015-0043 ◽

2015 ◽

Vol 70 (3) ◽

Cited By ~ 3

Author(s):

Stanislav Kalúz ◽

Martin Ševčík

Keyword(s):

New Species ◽

South Asia ◽

East Africa ◽

Geographic Distribution ◽

Strong Association ◽

Chigger Mite ◽

North East ◽

A New Species

AbstractA new chigger mite Grandjeana kanuchi sp. n. collected from the bat Cardioderma cor (Peters, 1872) (Megadermatidae) in Ethiopia (North-East Africa) is described. Additional comments on hosts and distribution records of the chiggers of genus Grandjeana are provided. With the newly described species the genus Grandjeana includes 10 species, three of them are occurring in Africa and seven in South Asia. Present findings suggest that this genus has the geographic distribution in Ethiopian and Oriental regions with a strong association with selected families of Chiroptera.

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Morpho-phenological diversity among Tunisian natural populations of Brachypodium hybridum

The Journal of Agricultural Science ◽

10.1017/s0021859614000689 ◽

2014 ◽

Vol 153 (6) ◽

pp. 1006-1016 ◽

Cited By ~ 5

Author(s):

M. NEJI ◽

F. GEUNA ◽

W. TAAMALLI ◽

Y. IBRAHIM ◽

M. SMIDA ◽

...

Keyword(s):

Genetic Diversity ◽

Geographic Distribution ◽

Phenotypic Diversity ◽

Average Length ◽

Natural Populations ◽

Negative Relationship ◽

Mantel Test ◽

Population Variation ◽

Long Distance ◽

Temperate Cereal

SUMMARYBrachypodium hybridum belongs to the Poaceae grass subfamily. It has a close genetic relationship with temperate cereal crops, which means that it can be used as a model for temperate cereal and grass crops. In order to improve knowledge on the genetic diversity of this species, 145 lines of B. hybridum representative of nine populations and all the ecoregions of Tunisia were characterized on the basis of 18 morpho-phenologic features. The results show a considerable variation between populations and ecoregions in all traits studied. Variation was relatively higher for reproductive than vegetative traits. The majority of traits showed very low to high heritability with low border value for average length of spikelet (ALS) and an average value of 0·64. It is noticeable that high values of heritability were observed for most vegetative descriptors, with low values for reproductive ones. Differentiation between populations (QST) varied from 0·02 for ALS to 0·78 for average length of leaves with a mean value across traits of 0·4, which confirms the wide intra-population variation in Tunisian natural population of B. hybridum. Pairwise QST showed that the greatest differentiation among populations was registered between Ain Drahem and Jbel Zaghouan and the smallest between Haouria and Raoued. Overall, the Ain Draham population showed the largest differentiation from the rest of the populations. To infer the effect of geographic distribution of the species, a Mantel test was applied between observed pairwise differentiation and geographic distance between populations and between ecoregions: the results show a positive, but not significant, relationship. In addition a significant negative relationship was found between phenotypic diversity and altitude, indicating that genetic diversity decreased with increasing altitude. Taken together, the high levels of intra-population variation and the lack of correlation between genetic differentiation and geographic distribution suggest a potentially important rate of long-distance seed dispersal and confirm the role played by natural selection in the population structure of Tunisian natural populations of B. hybridum.

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Genetic diversity and population structure analysis of bambara groundnut (Vigna subterrenea L) landraces using DArT SNP markers

PLoS ONE ◽

10.1371/journal.pone.0253600 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0253600

Author(s):

Charles U. Uba ◽

Happiness O. Oselebe ◽

Abush A. Tesfaye ◽

Wosene G. Abtew

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

West Africa ◽

East Africa ◽

Unknown Origin ◽

Snp Markers ◽

Bambara Groundnut ◽

Conservation Strategy ◽

Population Structure Analysis ◽

Geographical Regions

Understanding the genetic structure and diversity of crops facilitates progress in plant breeding. A collection of 270 bambara groundnut (Vigna subterrenea L) landraces sourced from different geographical regions (Nigeria/Cameroon, West, Central, Southern and East Africa) and unknown origin (sourced from United Kingdom) was used to assess genetic diversity, relationship and population structure using DArT SNP markers. The major allele frequency ranged from 0.57 for unknown origin to 0.91 for West Africa region. The total gene diversity (0.482) and Shannon diversity index (0.787) was higher in West African accessions. The genetic distance between pairs of regions varied from 0.002 to 0.028 with higher similarity between Nigeria/Cameroon-West Africa accessions and East-Southern Africa accessions. The analysis of molecular variance (AMOVA) revealed 89% of genetic variation within population, 8% among regions and 3% among population. The genetic relatedness among the collections was evaluated using neighbor joining tree analysis, which grouped all the geographic regions into three major clusters. Three major subgroups of bambara groundnut were identified using the ADMIXTURE model program and confirmed by discriminant analysis of principal components (DAPC). These subgroups were West Africa, Nigeria/Cameroon and unknown origin that gave rise to sub-population one, and Central Africa was sub-population two, while Southern and East Africa were sub-population three. In general, the results of all the different analytical methods used in this study confirmed the existence of high level of diversity among the germplasm used in this study that might be utilized for future genetic improvement of bambara groundnut. The finding also provides new insight on the population structure of African bambara groundnut germplasm which will help in conservation strategy and management of the crop.

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Molecular genetic diversity and differentiation of Nile tilapia (Oreochromis niloticus, L. 1758) in East African natural and stocked populations

10.21203/rs.2.11849/v3 ◽

2019 ◽

Author(s):

Papius Dias Tibihika ◽

Manuel Curto ◽

Esayas Alemayehu ◽

Herwig Waidbacher ◽

Charles Masembe ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

East Africa ◽

Oreochromis Niloticus ◽

Nile Tilapia ◽

Anthropogenic Activities ◽

Genetic Erosion ◽

Gene Pools ◽

East African ◽

Nile Tilapia Oreochromis Niloticus

Abstract Background The need for enhancing the productivity of fisheries in Africa triggered the introduction of non-native fish, causing dramatic changes to local species. In East Africa, the extensive translocation of Nile tilapia (Oreochromis niloticus) is one of the major factors in this respect. Using 40 microsatellite loci with SSR-GBS techniques, we amplified a total of 664 individuals to investigate the genetic structure of O. niloticus from East Africa in comparison to Ethiopian and Burkina Faso populations. Results All three African regions were characterized by independent gene-pools, however, the Ethiopian population from lake Tana showed to be more divergent than expected suggesting that it might be a different species. In East Africa, the genetic structure was congruent with both geographical location and anthropogenic activities. O. niloticus from Lake Turkana (Kenya) was isolated, while in Uganda, despite populations being rather similar to each other, two main natural catchments were able to be defined. We show that these two groups contributed to the gene-pool of different non-native populations. Moreover, admixture and possible hybridization with other tilapiine species may have contributed to the genetic divergence found in some populations such as Lake Victoria. We detected other factors that might be affecting Nile tilapia genetic variation. For example, most of the populations have gone through a reduction of genetic diversity, which can be a consequence of bottleneck caused by overfishing, genetic erosion due to fragmentation or founder effect resulting from stoking activities. Conclusions The anthropogenic activities particularly in the East African O. niloticus translocations, promoted admixture and contact with the native congenerics which may contribute to outbreeding depression and hence compromising the sustainability of the species in the region.

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