221 research outputs found
Flexible mating system in a logged population of Swietenia macrophylla King (Meliaceae): implications for the management of a threatened neotropical tree species.
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Extreme long-distance dispersal of the lowland tropical rainforest tree Ceiba pentandra L. (Malvaceae) in Africa and the Neotropics
Many tropical tree species occupy continental expanses of rainforest and flank dispersal barriers such as oceans and mountains. The role of long-distance dispersal in establishing the range of such species is poorly understood. In this study, we test vicariance hypotheses for range disjunctions in the rainforest tree Ceiba pentandra , which is naturally widespread across equatorial Africa and the Neotropics. Approximate molecular clocks were applied to nuclear ribosomal [ITS (internal transcribed spacer)] and chloroplast ( psb B- psb F) spacer DNA sampled from 12 Neotropical and five West African populations. The ITS ( N Â =Â 5) and psb B- psb F ( N Â =Â 2) haplotypes exhibited few nucleotide differences, and ITS and psb B- psb F haplotypes were shared by populations on both continents. The low levels of nucleotide divergence falsify vicariance explanations for transatlantic and cross-Andean range disjunctions. The study shows how extreme long-distance dispersal, via wind or marine currents, creates taxonomic similarities in the plant communities of Africa and the Neotropics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71417/1/j.1365-294X.2007.03341.x.pd
Mendelian inheritance, linkage and genotypic disequilibrium in microsatellite loci isolated from Hymenaea courbaril (Leguminosae).
The Neotropical tree Hymenaea courbaril, locally known as JatobĂĄ, is a valuable source of lumber and also produces comestible and medicinal fruit. We characterized Mendelian inheritance, linkage and genotypic disequilibrium at nine microsatellite loci isolated from H. courbaril, in order to determine if they would provide accurate estimates of population genetic parameters of this important Amazon species. The study was made on 250 open-pollinated offspring originated from 14 seed trees. Only one of nine loci presented significant deviation from the expected Mendelian segregation (1:1). Genotypic disequilibrium between pairwise loci was investigated based on samples from 55 adult and 56 juvenile trees. No genetic linkage between any paired loci was observed. After Bonferroniâs corrections for multiple tests, we found no evidence of genotypic disequilibrium between pairs of loci. We conclude that this set of loci can be used for genetic diversity/structure, mating system, gene flow, and parentage analyses in H. courbaril populations
Mendelian inheritance, linkage and genotypic disequilibrium in microsatellite loci isolated from Hymenaea courbaril (Leguminosae).
The Neotropical tree Hymenaea courbaril, locally known as JatobĂĄ, is a valuable source of lumber and also produces comestible and medicinal fruit. We characterized Mendelian inheritance, linkage and genotypic disequilibrium at nine microsatellite loci isolated from H. courbaril, in order to determine if they would provide accurate estimates of population genetic parameters of this important Amazon species. The study was made on 250 open-pollinated offspring originated from 14 seed trees. Only one of nine loci presented significant deviation from the expected Mendelian segregation (1:1). Genotypic disequilibrium between pairwise loci was investigated based on samples from 55 adult and 56 juvenile trees. No genetic linkage between any paired loci was observed. After Bonferroniâs corrections for multiple tests, we found no evidence of genotypic disequilibrium between pairs of loci. We conclude that this set of loci can be used for genetic diversity/ structure, mating system, gene flow, and parentage analyses in H. courbaril populations
Prey preference of the common vampire bat (Desmodus rotundus, Chiroptera) using molecular analysis
Morphological identification of prey fragments in vampire bat feces is impossible because of an exclusively blood-based diet. Therefore, studies of their foraging ecology require innovative approaches. We investigated the diet of Desmodus rotundus using a PCR-restriction fragment length polymorphism (RFLP) molecular method by amplifying the cytochrome b mitochondrial gene (380 bp) from DNA fecal samples collected from captive bats fed with blood from chickens, cattle, pigs, dogs, and humans - the 5 most frequently attacked prey species in rural areas of the Brazilian Amazonia. The prey preference of the vampire bat was investigated in 18 riverine villages, where the availability of domestic animals to bats was quantified. Prey DNA amplified from fecal samples exhibited no visible signals of vampire bat DNA. A PCR - RFLP flowchart and a combination of 2 DNA restriction enzymes allowed the direct identification of prey to species level. The enzymes' restriction profile did not overlap with those of vampire bats or wild mammal and avian species. Chickens were the most attacked prey species (61.4% of the identifications, n = 27), but pigs were highly preferred in relation to prey availability. This suggests a preference for mammalian blood in D. rotundus diet, with chickens exploited as a secondary food source. No wild vertebrate species was identified in the fecal samples, indicating that vampire bats are selectively feeding on the blood of domesticated animals, probably because they are more predictable and easily accessed resources. © 2015 American Society of Mammalogists
Brief Note Mendelian inheritance, linkage and genotypic disequilibrium in microsatellite loci isolated from Hymenaea courbaril (Leguminosae)
AnĂĄlise da herança de locos microsatĂ©lites marcados com fluorescĂȘncia em sumaĂșma (Ceiba pentandra) e estimativa de fecundação cruzada em populaçÔes naturais.
Conservation implications of the mating system of the Pampa Hermosa landrace of peach palm analyzed with microsatellite markers
Peach palm (Bactris gasipaes) is cultivated by many indigenous and traditional communities from Amazonia to Central America for its edible fruits, and is currently important for its heart-of-palm. The objective of this study was to investigate the mating system of peach palm, as this is important for conservation and breeding. Eight microsatellite loci were used to genotype 24 open-pollinated progenies from three populations of the Pampa Hermosa landrace maintained in a progeny trial for genetic improvement. Both the multi-locus outcrossing rates (0.95 to 0.99) and the progeny level multi-locus outcrossing rates (0.9 to 1.0) were high, indicating that peach palm is predominantly allogamous. The outcrossing rates among relatives were significantly different from zero (0.101 to 0.202), providing evidence for considerable biparental inbreeding within populations, probably due to farmers planting seeds of a small number of open-pollinated progenies in the same plot. The correlations of paternity estimates were low (0.051 to 0.112), suggesting a large number of pollen sources (9 to 20) participating in pollination of individual fruit bunches. Effective population size estimates suggest that current germplasm collections are insufficient for long-term ex situ conservation. As with most underutilized crops, on farm conservation is the most important component of an integrated conservation strategy. © 2015, Sociedade Brasileira de Genética. Printed in Brazil
Conservation implications of the mating system of the Pampa Hermosa landrace of peach palm analyzed with microsatellite markers
Peach palm (Bactris gasipaes) is cultivated by many indigenous and traditional communities from Amazonia to Central America for its edible fruits, and is currently important for its heart-of-palm. The objective of this study was to investigate the mating system of peach palm, as this is important for conservation and breeding. Eight microsatellite loci were used to genotype 24 open-pollinated progenies from three populations of the Pampa Hermosa landrace maintained in a progeny trial for genetic improvement. Both the multi-locus outcrossing rates (0.95 to 0.99) and the progeny level multi-locus outcrossing rates (0.9 to 1.0) were high, indicating that peach palm is predominantly allogamous. The outcrossing rates among relatives were significantly different from zero (0.101 to 0.202), providing evidence for considerable biparental inbreeding within populations, probably due to farmers planting seeds of a small number of open-pollinated progenies in the same plot. The correlations of paternity estimates were low (0.051 to 0.112), suggesting a large number of pollen sources (9 to 20) participating in pollination of individual fruit bunches. Effective population size estimates suggest that current germplasm collections are insufficient for long-term ex situ conservation. As with most underutilized crops, on farm conservation is the most important component of an integrated conservation strategy
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