There is an increasing evidence that populations of ectotherms can diverge genetically in response to different climatic conditions, both within their native range and (in the case of invasive ...species) in their new range. Here, we test for such divergence in invasive whitefly Bemisia tabaci populations in tropical Colombia, by considering heritable variation within and between populations in survival and fecundity under temperature stress, and by comparing population differences with patterns established from putatively neutral microsatellite markers. We detected significant differences among populations linked to mean temperature (for survival) and temperature variation (for fecundity) in local environments. A QST − FST analysis indicated that phenotypic divergence was often larger than neutral expectations (QST > FST). Particularly, for survival after a sublethal heat shock, this divergence remained linked to the local mean temperature after controlling for neutral divergence. These findings point to rapid adaptation in invasive whitefly likely to contribute to its success as a pest species. Ongoing evolutionary divergence also provides challenges in predicting the likely impact of Bemisia in invaded regions.
Prodiplosis longifila is reported as a pest of a wide range of species cultivated in America, including citrus, solanaceous species and asparagus. This species has different behavioural traits that ...are primarily centred on the oviposition habit and the feeding of larvae, which can change depending on the host. However, scarce information is available on population studies and the natural history of this insect, and uncertainty exists about the taxonomic identity and the geographic distribution of this species. The main objective was to perform a phylogenetic and genetic study of P. longifila populations and to define whether the North American and South American populations belong to the same species or whether a differentiation process had occurred due to geographic distance. A second objective was to determine whether this species showed genetic differentiation by host specialization in South America. The phylogenetic and population analyses based on DNA barcodes (cytochrome oxidase I gene) and a region of the ribosomal DNA (ITS2) revealed divergent clades attributable to geographic distance and host specificity. The North American and South American P. longifila insects were confirmed to be genetically distinct, and the genetic distances exceeded the values expected for intraspecific variation. In South America, the population analysis of P. longifila from tomato, sweet pepper (Solanaceae), Tahiti lime and key lime (Rutaceae) hosts evidenced high genetic differentiation between populations associated with different hosts and an absence of gene flow between these groups, suggesting the corresponding formation of cryptic species.
We investigated the genetic variation of Avicennia germinans using 172 AFLP (Amplified Fragment Length Polymorphism) bands of 45 plants from four localities on the Colombian Pacific coast: 11 from ...Virudó (Chocó), 10 from La Plata (Valle), 12 from Tumaco (Nariño), and 12 from Chontal (Nariño). AFLP variation among localities (16.2%) was highly significant (AMOVA; Ρ < 0.0001). All the analyses showed that Tumaco was the most genetically distinct locality of the four under study. The other three localities, La Plata, Virudó, and Chontal, apparently form a large single subpopulation with high-to-moderate gene flow among localities. We also found the genetic diversity of A. germinans on the Colombian Pacific coast ($H_{E}$= 0.251) higher than that estimated by others over the broad geographic range of Α. germinans. All these results together show that mangroves on the Colombian Pacific coast deserve a strong investigative effort to improve our ecological, evolutionary, and biogeographic knowledge of this important tropical forest type. /// Se investigó la variación genética de Avicennia germinans de cuatro localidades de la costa Pacífica colombiana. Para esto, se muestrearon un total de 45 árboles distribuidos así: 11 de Virudó (Chocó), 10 de La Plata (Valle), 12 de Tumaco (Nariño), y 12 de Chontal (Nariño). En el análisis estadístico se utilizaron 172 bandas del marcador molecular AFLP (Amplified Fragment Length Polymorphism). Se encontró una variación entre localidades altamente significativa (AMOVA; Ρ < 0.0001) equivalente a 16.2 por ciento. Todos los análisis estadísticos mostraron que Tumaco es una subpoblación genéticamente diferente de las otras tres localidades estudiadas. Las otras tres localidades estudiadas (La Plata, Virudó y Chontal), aparentemente forman otra subpoblación grande con flujo genético moderado y alto. También se encontró que la diversidad genética promedio de A. germinans de la Costa Pacífica Colombiana ($H^{E}$= 0.251) es más alta que la que se ha reportado para otros sitios donde esta especie se distribuye. En conjunto, todos estos resultados indican que esta especie y en general los manglares de la costa Pacífica colombiana requieren de un mayor esfuerzo de investigación para mejorar el conocimiento ecológico, evolutivo y biogeográfico de este bosque tropical.
This study analyzed the genetic diversity and patterns of genetic structure in Colombian populations of
Avicennia germinans L. using microsatellite loci. A lower genetic diversity was found on both ...the Caribbean (Ho
=
0.439) and the Pacific coasts (Ho
=
0.277) than reported for the same species in other locations of Central American Pacific, suggesting the deterioration of genetic diversity. All the populations showed high inbreeding coefficients (0.131–0.462) indicating heterozygotes deficience. The genetic structure between the Colombian coasts separated by Central American Isthmus was high (
F
RT
=
0.39) and the analyses of the genetic patterns of
A. germinans revealed a clear differentiation of populations and no-recent gene flow evidence between coasts. Genetic structure was found within each coast (
F
ST
=
0.10 for the Caribbean coast and
F
ST
=
0.22 for the Pacific coast). The genetic patterns along the two coasts appear to reflect a forcing by local geomorphology and marine currents. Both coasts constitute a different Evolutionary Significant Unit, so we suggest for future transplantations plans that propagules or saplings of the populations of the Caribbean coast should not be mixed with those of the Pacific Colombian coast. Besides, we suggest that reforestation efforts should carefully distinguish propagules sources within each coast.
Pelliciera rhizophorae is a Neotropical mangrove species whose distribution is mostly restricted to the Pacific Coast, between the Gulf of Nicoya (Costa Rica) and the Esmeraldas River (Ecuador). In ...the Caribbean, patches of Pelliciera have been found in Nicaragua, Panama, and Colombia. The genetic variation and the population structure of P. rhizophorae were evaluated in six zones of the Colombian Pacific, using AFLP molecular markers. Of the 225 amplified fragments produced, 155 (69%) were polymorphic in 57 individuals of P. rhizophorae collected in the localities of Virudó, Charambirá, La Plata Island, Tumaco, Milagros, and Chontal. Genetic diversity within populations varied significantly, with the lowest levels of within-population variation ($H_{ep}$= 0.081 and 0.090, respectively) in La Plata Island and Tumaco; and the highest level of variation ($H_{ep}$= 0.187) in Chontal. In the Colombian Pacific, P. rhizophorae was significantly structured, with 26.5 percent of the variation found among populations, which was an evidence of substructure within populations. Genetic differentiation was not related to the geographic distance between zones. This suggests that the population dynamics of P. rhizophorae could be associated with historic processes influenced by ecological and environmental factors such as the movement of pollen by birds, the displacement of propagules by marine currents, and the spatial distribution of favorable habitats. /// Pelliciera rhizophorae es una especie de mangle neotropical cuya distribución está casi restringida a la Costa Pacífica, entre el Golfo de Nicoya (Costa Rica) y el río Esmeraldas (Ecuador). En el Caribe, se han encontrado parches de Pelliciera en Nicaragua, Panamá y Colombia. La variación genética y la estructura poblacional de Pelliciera rhizophorae en seis zonas del Pacífico colombiano fueron evaluadas utilizando marcadores moleculares AFLP, produciendo en total 225 fragmentos amplificados, de los cuales 155 (69%) fueron polimórficos en 57 individuos de Pelliciera rhizophorae colectados en las localidades de Virudó, Charambirá, Isla La Plata, Tumaco, Milagros, y Chontal. La diversidad genética dentro de poblaciones varió significativamente, mostrando en Isla La Plata y Tumaco los niveles de variación intrapoblacional más bajos ($H_{ep}$= 0.081 y 0.090 respectivamente) y en Chontal el nivel más alto de variación ($H_{ep}$= 0.187). En el Pacífico Colombiano, P. rhizophorae resultó significativamente estructurada con 26.5 por ciento de variación dentro de poblaciones, mostrando evidencias de subestructuración dentro de poblaciones. La diferenciación genética no mostró relación con la distancia geográfica entre zonas. Esto sugiere que la dinámica poblacional de Pelliciera podría asociarse con procesos históricos influenciados por factores ecológicos y ambientales como el movimiento de polen mediado por aves, el desplazamiento de propágulos a través de las corrientes marinas y la distribución espacial de hábitat favorables.
Twenty‐six microsatellite loci were isolated and characterized from the mangrove species Rhizophora mangle using (GT)n and (CT)n repeats. Eighty‐four per cent of the clones contained microsatellite ...sequences; the most common dinucleotides were the (GA/CT) and (CA/GT) repeats. Ten primers were selected to investigate the polymorphism among individuals of R. mangle from two natural populations of the Colombian Pacific Coast. The observed heterozygosity per locus varied from 0.20 to 0.80, the power of discrimination was 0.32–0.84 and the power of exclusion was 0.03–0.75. This set of microsatellites offers an efficient tool for population genetics studies on this species.
Abstract
There is an increasing evidence that populations of ectotherms can diverge genetically in response to different climatic conditions, both within their native range and (in the case of ...invasive species) in their new range. Here, we test for such divergence in invasive whitefly
B
emisia tabaci
populations in tropical Colombia, by considering heritable variation within and between populations in survival and fecundity under temperature stress, and by comparing population differences with patterns established from putatively neutral microsatellite markers. We detected significant differences among populations linked to mean temperature (for survival) and temperature variation (for fecundity) in local environments. A
Q
ST
−
F
ST
analysis indicated that phenotypic divergence was often larger than neutral expectations (
Q
ST
>
F
ST
). Particularly, for survival after a sublethal heat shock, this divergence remained linked to the local mean temperature after controlling for neutral divergence. These findings point to rapid adaptation in invasive whitefly likely to contribute to its success as a pest species. Ongoing evolutionary divergence also provides challenges in predicting the likely impact of
B
emisia
in invaded regions.
Sampling performed in flower buds of citrus in Colombia allowed the detection of the presence of Prodiplosis longifila Gagné and Prodiplosis floricola Felt (Diptera: Cecidomyiidae). The polyphagous ...P. longifila is a pest of Solanaceae, but whether both species cause economic losses in citrus is unknown. These congeneric species are indistinguishable in the larval stage, and their morphological identification, which is complex, is performed on adult males. This study comprises a morphological description and characterization of the damage generated by P. floricola larvae feeding on the flowers of key lime, Citrus × aurantiifolia (Christm.) Swingle (pro. sp.), and Tahiti lime, Citrus × latifolia Tanaka ex Q. Jiménez (Rutaceae), as well as a population genetical analysis of the insect. Prodiplosis floricola was found in the localities of Támesis (Antioquia), Garzón (Huila), and Palmira and Zarzal (Valle del Cauca). These populations were characterized by COI and ITS2 molecular markers, with a moderate genetic structure found that cannot be explained by the geographic distance between the populations. The haplotype distribution pattern indicates that the populations are composed of highly differentiated haplotypes of equivalent frequencies, which suggests that the Colombian populations of P. floricola are products of multiple introductions and that their dispersion between populations is attributable to anthropic transport. Citrus in Colombia constitutes a new host for P. floricola and increases the known geographical range of the insect, as it has only been previously reported in Brazil and the USA. The molecular markers used in the present study are useful for early diagnosis of P. floricola in the larval stage and for future research on the population dynamics in citrus.
Mitochondrial and nuclear markers (COI and ITS2) were used to investigate genetic variation and structure among populations of the bud midge Prodiplosis floricola (Diptera: Cecidomyiidae) in Colombia. The populations appear product of multiple introductions and dispersion between populations is attributable to anthropic transport. The presence of P. floricola in key lime and Tahiti lime crops in Colombia constitutes a new report of a host (citrus) for the species and increases its known geographical range.
Prodiplosis longifila Gagné (Diptera: Cecidomyiidae) is an insect pest that attacks various types of crops, including tomato, Solanum lycopersicum L. (Solanaceae), a vegetable with substantial ...economic significance worldwide. Prodiplosis longifila is a widely distributed pest in Colombia, Ecuador, and Peru, countries characterized by the presence of significant geographic barriers like the Andes Mountains. It has been reported that geographic barriers affect the dynamics and genetic differentiation of insect populations. Therefore, the aim of this study was to assess the diversity, genetic structure, and demographic history of P. longifila through the analysis of sequences within the mitochondrial region of cytochrome oxidase I (COI) and rDNA‐ITS2 in 27 populations located in Colombia and Ecuador. Analyses were performed on populations distributed in three geographic groups separated by the presence of the Andes Mountains. A total of 11 haplotypes were identified with the COI gene and only one haplotype in the rDNA‐ITS2 was found. Analyses of population structure and demographic history revealed that there is a structure associated with the Andes, which is reflected in an uneven distribution of the haplotype frequencies between regions, but even so, gene flow between populations was detected which produces low genetic differentiation. Because P. longifila has a short‐range dispersion that determines its territorial nature, it would be expected that other factors are producing the genetic exchange between populations. We suggest that the anthropogenic effect produced by farming practices, such as the use of seedlings as seed, which may carry P. longifila larvae, cause passive dispersal of pest throughout the Andes, particularly in Colombia.
Con el objetivo de determinar el grado de diversidad genética del mangle negro o iguanero(Avicennia germinans L.) se analizaron cuatro localidades ecológicamente diferentes de la costaPacífica ...colombiana utilizando el marcador molecular AFLP “Amplified Fragment LengthPolymorphism”. Para esto, se colectaron hojas jóvenes de 45 individuos de diferentes edades, encuatro localidades de la costa Pacífica colombiana, así: 10 de Virudó-Chocó, 11 de Isla La Plata-Valle del Cauca, 12 de Tumaco-Nariño y 12 de Chontal-Nariño. El patrón de bandas obtenidose transformó en una matriz de presencias (1) o ausencias (0) de la banda. Con esta matriz, sehicieron tres Análisis Moleculares de Varianza (AMOVA), así: 1) Dividiendo la variación genéticaen dos niveles jerárquicos, entre localidades y dentro de localidades, sin considerar categorías deedad. 2) Dividiendo la variación genética en tres niveles jerárquicos, entre localidades, entrecategorías de edad dentro de localidades y dentro de categorías de edad. 3) Dividiendo la va-riación genética en dos niveles jerárquicos, entre localidades y dentro de localidades para doscategorías de edad: Fustales y latizales/brinzales.
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