CEAZA
Implications of farmers’ seed exchanges for on-farm conservation of quinoa, as revealed by its genetic diversity in Chile.
Fuentes, F., Bazile, D., Bhargava, A., & Martínez, E.
Quinoa cultivation in Chile presents an ancient and active complex of geographic, climatic, social and cultural interactions that has determined its current biodiversity in the three main growing zones (north, central and south). Importantly, these interactions involve the participation of farmers, whose activities are at the base of seed exchange networks due to their knowledge and in situ conservation of genetic diversity. The present study reports how a better understanding of farmers’ seed exchanges and local production practices could impact the genetic structure and diversity of quinoa at national scale in Chile. Using field interviews and characterization of 20 microsatellite genetic markers in a multi-origin set of 34 quinoa accessions representative of Chile and the South American region, the phenetic analysis of germplasm was consistent with the current classification of quinoa ecotypes present in Chile and Andean zone. This allowed the identification of five populations, which were represented by quinoa of Salares (northern Chile), Coastal/Lowlands (central and southern Chile), Highlands (Peru, Bolivia and Argentina) and Inter-Andean Valleys (Ecuador and Colombia). The highly informative quality of the markers used revealed a wide genetic diversity among main growing areas in Chile, which correlated well with natural geographical–edaphic–climatic and social–linguistic context to the expansion of quinoa biodiversity. Additionally, in addition to ancient seed exchanges, this process is still governed by the diverse agricultural practices of Andean farmers. Genetic erosion is considered an imminent risk due to small-scale farming, where the influence of increased migration of people to urban systems and export-driven changes to the agro-ecosystems may further reduce the diversity of quinoa plants in cultivation.
Año: 2012
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Referencia APA: Fuentes, F., Bazile, D., Bhargava, A., & Martínez, E. (2012). Implications of farmers’ seed exchanges for on-farm conservation of quinoa, as revealed by its genetic diversity in Chile. J. Agric. Sci., 150(06), 702-716.
An Early Holocene task camp (~8.5 ka cal BP) on the coast of the semi-arid north of Chile.
Ballester, B., Jackson, D., Carré, M., Maldonado, A., Méndez, C., & Seguel, R.
According to current thinking, the peopling of South America involved a coastal as well as an inland exploitation. Here the authors describe a camp that may denote a transition between the two. As indicated by bifacial tools, the investigation shows that people began to move inland and hunt mammals around 8500 cal BP, perhaps in association with a change in the climate.
Año: 2012
Palabras claves: Chile, peopling of South America, coastal, inland, shell, midden, bifacies
Referencia APA: Ballester, B., Jackson, D., Carré, M., Maldonado, A., Méndez, C., & Seguel, R. (2012). An Early Holocene task camp (~8.5 ka cal BP) on the coast of the semi-arid north of Chile. Antiquity, 86(331), 88-98.
Lizards on Ice: Evidence for Multiple Refugia in Liolaemus pictus (Liolaemidae) during the Last Glacial Maximum in the Southern Andean Beech Forests.
Vera-Escalona, I., D'Elía, G., Gouin, N., Fontanella, F., Muñoz-Mendoza, C., Sites, J., & Victoriano, P.
Historical climate changes and orogenesis are two important factors that have shaped intraspecific biodiversity patterns worldwide. Although southern South America has experienced such complex events, there is a paucity of studies examining the effects on intraspecific diversification in this part of the world. Liolaemus pictus is the southernmost distributed lizard in the Chilean temperate forest, whose genetic structure has likely been influenced by Pleistocene glaciations. We conducted a phylogeographic study of L. pictus in Chile and Argentina based on one mitochondrial and two nuclear genes recovering two strongly divergent groups, Northern and Southern clades. The first group is distributed from the northernmost limit of the species to the Araucanía region while the second group is distributed throughout the Andes and the Chiloé archipelago in Southern Chile. Our results suggest that L. pictus originated 751 Kya, with divergence between the two clades occurring in the late Pleistocene. Demographic reconstructions for the Northern and Southern clades indicate a decrease in effective population sizes likely associated with Pleistocene glaciations. Surprisingly, patterns of genetic variation, clades age and historical gene flow in populations distributed within the limits of the Last Glacial Maximum (LGM) are not explained by recent colonization. We propose an “intra-Andean multiple refuge” hypothesis, along with the classical refuge hypothesis previously proposed for the biota of the Chilean Coastal range and Eastern Andean Cordillera. Our hypothesis is supported by niche modelling analysis suggesting the persistence of fragments of suitable habitat for the species within the limits of the LGM ice shield. This type of refuge hypothesis is proposed for the first time for an ectothermic species.
Año: 2012
Palabras claves: Haplotypes, Phylogeography, Gene flow, Chile (country), Phylogenetic analysis, Population genetics, Mitochondrial DNA, Mitochondria.
Referencia APA: Vera-Escalona, I., D'Elía, G., Gouin, N., Fontanella, F., Muñoz-Mendoza, C., Sites, J., & Victoriano, P. (2012). Lizards on Ice: Evidence for Multiple Refugia in Liolaemus pictus (Liolaemidae) during the Last Glacial Maximum in the Southern Andean Beech Forests. Plos ONE, 7(11), e48358.
Impact of mycorrhizae and irrigation in the survival of seedlings of Pinus radiata D. Don subject to drought.
Atala, C., Muñoz-Capponi, E., Pereira, G., Navarrete, E., Oses, R., & Molina-Montenegro, M.
In drought condition, plants increase survival chance by adjusting their functional traits and by biological associations. Mycorrhizae association and artificial watering have been shown to increase plant survival under drought, especially at early developmental stages when plants are more susceptible. In Chile, Pinus radiata is the most important forest species. It is grown mainly in Central Chile, where precipitations are predicted to drop in 40% and change in frequency in the future due to climate change. Rhizopogon luteolus is an ectomycorrhizae usually associated with Pinus species and has been found to increase drought tolerance. We addressed the effect of R. luteolus inoculation on survival and functional traits of P. radiata seedlings exposed to two watering treatments. These treatments simulated control (50 ml) and 40% reduced precipitations (20 ml). We also evaluated the combined effect of watering quantity (20 and 50 ml) and frequency (every 5, 10 and 30 days) on the same variables. R. luteolus inoculation increased seedling survival, but reduced plant size. Watering quantity affected plant survival only at intermediate watering frequencies, but not at the high and low frequencies. The lowest frequency, normal for the summer of Central Chile, resulted in -80% seedling mortality. Most of the functional traits measured were not affected neither by watering frequency nor quantity, but they were affected by mycorrhization. Mycorrhizae inoculation, together with some sort of artificial watering could be a possible strategy to cope with prolonged drought events.
Año: 2012
Palabras claves: Pinus radiata, Rhizopogon luteolus, climate change, ectomycorrhizae, drought tolerance.
Referencia APA: Atala, C., Muñoz-Capponi, E., Pereira, G., Navarrete, E., Oses, R., & Molina-Montenegro, M. (2012). Impact of mycorrhizae and irrigation in the survival of seedlings of Pinus radiata D. Don subject to drought. Gayana Bot., 69(2), 296-304.
What do we know about high-altitude precipitation in the semi-arid Andes of Chile?
Bourgin P, Andreassian V, Gascoin S, Valery A.
Mapping precipitations on a regular grid is often required for hydrological and ecological modelling. The spatial interpolation methods are generally used to estimate such a distribution from ground-based measurements. In the case of mountainous areas, the estimation of precipitation amounts is still a challenging task and the results of spatial interpolation should be verified as much as possible. Here we describe a three-steps method for the validation of a precipitation map. This is used in the context of a mountainous semi-arid region, the Norte Chico in Chile (26°S-32°S). The implementation of this validation method showed the benefits of an interpolation method developed by Valéry [2010] for mountainous areas. The hydrological balance of the high-altitude watersheds is now more realistic.
Año: 2012
Palabras claves: Precipitation, spatial interpolation method, extrapolation, altitude, altitudinal corrections, validation, water equivalent, water balance.
Referencia APA: Bourgin P, Andreassian V, Gascoin S, Valery A. (2012). Que sait-on des précipitations en altitude dans les Andes semi-arides du Chili?. La Houille Blanche. 2012;(2):12-17.