Biogeography of wild Arachis (Leguminosae):distribution and environmental characterisation (original) (raw)
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Crop Science, 2003
The conservation status of wild Arachis spp. is not well characterized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives were to use 2175 georeferenced observations of wild peanut (Arachis spp.) to assess the conservation status of the genus and to prioritize biologically and geographically future conservation actions. Species distribution predictions were made on the basis of 36 climate variables, and these data were synthesized with land‐use data to map the potential distribution of each species, and hence the species richness of the whole genus, excluding A. hypogea hotspots of species richness were found in Mato Grosso around Cuiabá and Campo Grande in Brazil and around the Serra Geral de Goias, northeast of Brasilia. The current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. Several species were identified as being under ...
Nuevas especies de Arachís (Leguminosae) de Brasil, Paraguay y Bolivia
Bonplandia
Se describen once especies nuevas de Arachís L. (Leguminosae), que representan siete de las nueve secciones taxonómicas del género. Ocho de las nuevas especies fueron citadas y clasificadas en la monografía de Krapovickas & Gregory, pero son ahora tratadas con su propio epíteto específico; una especie fue recolectada antes de 1994, pero el material dejaba suficientes dudas como para no incluirla en la monografía, y dos especies fueron recolectadas después que la misma fuera sometida a publicación. La descripción de esas once especies ayudará a clarificar la sistemática del género Arachís, así como a la comprensión de las líneas evolutivas de ciertos materiales importantes, algunos de los cuales podrían haber tenido un rol en los eventos que llevaron al origen del maní cultivado
Biogeography of wild Arachis: assessing conservation status and setting future priorities
2003
plant species are threatened globally, equivalent to some 12.5% of the estimated world flora. Other estimates The conservation status of wild Arachis spp. is not well charactersuggest that 25 to 35% of plant genetic diversity could ized for its maintenance and possible future exploitation for the improvement of cultivated peanut, Arachis hypogaea L. Our objectives be lost in the next 20 yr. Those taxa that include crop were to use 2175 georeferenced observations of wild peanut (Arachis species and their wild relatives (crop gene pools) are of spp.) to assess the conservation status of the genus and to prioritize particular concern from a conservation perspective. The biologically and geographically future conservation actions. Species economic and social consequences of such an irredeemdistribution predictions were made on the basis of 36 climate variables, able loss of plant diversity, combined with rapid human and these data were synthesized with land-use data to map the potenpopulation growth, could be potentially disastrous. The tial distribution of each species, and hence the species richness of the conservation of plant diversity, particularly of those spewhole genus, excluding A. hypogea. hotspots of species richness were cies essential for human nutrition and crop improvefound in Mato Grosso around Cuiabá and Campo Grande in Brazil ment, is of critical importance. One of the most pressing and around the Serra Geral de Goias, northeast of Brasilia. The challenges facing biologists today is the description of current state of in situ conservation areas poorly represents wild peanut, with only 48 of the 2175 observations from National Parks. biological diversity at the ecosystem, species, and ge-Several species were identified as being under threat of extinction.
Organography of greenhouse and field accessions of wild Arachis species (section Arachis
Peanut or groundnut (Arachis hypogaea L.) is a globally important oilseed crop, with important nutritional qualities, and a rich source of amino acids and protein. Another 80 species have been described in the genus Arachis, 64 of which are found in Brazil, and even though their morphology and agronomic traits remain largely unknown, they have been cultivated for forage and for landscaping and have great potential for breeding with cultivated peanut. Thus, the morphological characterization of wild Arachis species is essential for their conservation and use. In this study, we present a morphological and agronomic characterization of 29 diploid accessions of eleven wild Arachis species and one of the tetraploid A. monticola (section Arachis) with A and B genomes and determine their intra-and interspecific variability in greenhouse and field conditions. In total, 35 morphological descriptors were developed a priori from greenhouse accessions in the first crop year and used in field accessions in the second crop year. Significant differences in descriptors compiled in the greenhouse and the field support the use of different descriptors for different experimental conditions. PCA analysis showed that the distribution of accessions accorded with the taxonomy of species. The ten morphological descriptors that were important in differentiating section Arachis accessions were seed length, lateral branch length, right apical leaflet length, right apical leaflet width, height and diameter of main stem, branch color, standard petal base color, number of flowers, and presence of bristles on rachis.
Landscapes with Araucaria in South America: evidence for a cultural dimension
Ecology and Society, 2014
South American Araucaria species include Araucaria araucana (Mol.) C. Koch (Argentina and Chile) and Araucaria angustifolia (Bert.) O. Kuntze (Brazil and Argentina). Both species produce nut-like seeds (piñones, pinhões) that have, since pre-Columbian times, formed part of the traditional diet of local societies: Kaingang (A. angustifolia) and Mapuche-Pehuenche (A. araucana). In this work, we compared and analyzed converging and diverging characteristics of these species founded on ecological and ethnobotanical evidence. We also studied the role of human groups in the construction of Araucaria forests. The methodology used was based on a bibliographical analysis that included a wide range of sources, from ecological to social sciences. Our results show that both species hold strong cultural and symbolic significance for associated human groups. The ecological characteristics of both species have favored their rapid territorial expansion since the Holocene; however, palynological, archaeological, and ethnobotanical evidence reinforces the hypothesis that the human groups involved played a key role in this process. For both societies, there are records of past and present practices related to the transport, storage, and processing of the seeds. The landscapes where A. araucana and A. angustifolia are present also reflect use patterns that hold a level of significance that goes beyond merely utilitarian purposes. For the Kaingang and the Mapuche-Pehuenche, the Araucaria forests are associated with the concept of territoriality and play a key role in determining their identity. Our approach to cultural landscapes, which considers the importance of societies in the modelling of natural landscapes, can offer new perspectives for conservation policies and action in both forests.
Genetic variability of Brazilian Indian landraces of Arachis hypogaea L
Genetics and molecular research : GMR, 2007
The Kayabi Indians who inhabit the Xingu Indigenous Park, located in West Central Brazil, have grown and managed peanuts for a long time. A great number of landraces are being maintained by these tribes and some of this germplasm has morphological traits that exceed the variation described in the taxonomic literature. Here, we analyzed the genetic variability of these landraces using a set of microsatellite markers. The analysis showed that, in general, the indigenous samples grouped according to the villages where they were collected. The microsatellite markers used in the present study detected high levels of genetic variation. Similarity groups, genetically distant from each other, were formed, allowing a more efficient use of the existing genetic variability. The present study also showed that these materials can extend the genetic variability available for peanut-breeding programs. Additionally, the microsatellite markers revealed a large dissimilarity among germplasm accession...
Genetic Resources and Crop Evolution, 2005
The genus Arachis is divided into nine taxonomic sections. Section Arachis is composed of annual and perennial species, while section Heteranthae has only annual species. The objective of this study was to investigate the genetic relationships among 15 Brazilian annual accessions from Arachis and Heteranthae using RAPD markers. Twenty-seven primers were tested, of which nine produced unique fingerprintings for all the accessions studied. A total of 88 polymorphic fragments were scored and the number of fragments per primer varied from 6 to 17 with a mean of 9.8. Two specific markers were identified for species with 2n ¼ 18 chromosomes. The phenogram derived from the RAPD data corroborated the morphological classification. The bootstrap analysis divided the genotypes into two significant clusters. The first cluster contained all the section Arachis species, and the accessions within it were grouped based upon the presence or absence of the 'A' pair and the number of chromosomes. The second cluster grouped all accessions belonging to section Heteranthae.
Genetic diversity within and among Chilean Araucaria araucana populations was estimated using allozyme variability. A total of 537 individuals were sampled from nine populations. Twelve loci were scored in all populations and used for analyses. In general, the genetic variability of A. araucana were high as shown by mean expected heterozygosity (H E = 0.151), percentage of polymorphic loci (P = 91.7%), mean number of alleles per locus (A = 1.73) and mean number of alleles per polymorphic locus (A P = 2.4). Although the most of this genetic variation was within populations (H S = 0.151), an important proportion of the total genetic diversity (H T = 0.212) was among population (G ST = 0.287). To analyze the relationships between populations we constructed a tree based on Nei's genetic distances using UPGMA methods, and calculated F ST between population pairs. Our results showed complex patterns of genetic relationships among Chilean Araucaria araucana populations. Tree topology suggested the existence of three distinct groups of populations: The first group included populations from low-elevation central Andean range and Coastal range populations. The second group, included northern Andean populations. The third group of populations was composed of central high-elevation Andean populations. These patterns of population clustering are congruent with multiple glacial refugia hypothesis. In order to understand the present patterns of distribution of the genetic diversity and post-glacial colonization routes of Araucaria araucana, paleogeographical, paleoclimatic and biogeographical evidence is discussed.
Conservation Genetics
Araucaria (Araucaria angustifolia (Bert.) O. Ktze) is a primarily dioecious species threatened with extinction that plays an important social and economic role especially in the southern region of Brazil. The aim of this work is to investigate the diversity and likely determinants of genetic lineages in this species for conservation management. For this, a collection of 30-year-old Araucaria was used. Accessions collected from 12 sites across the species range were analyzed, with ten individuals per site. The SSR genotyping was conducted with 15 loci and the data were analyzed using several complementary approaches. Descriptive statistics among sampling sites were used and diversity was partitioned non-hierarchically to estimate the size and composition of genetic clusters using a Bayesian assignment method. To explore possible biological implications of differences between Niche Models and habitat suitability, a series of statistical procedures were used, and tests were carried out...