Instituto Multidisciplinario Of Biologia Vegetal
Instituto Multidisciplinario Of Biologia Vegetal
Bonito G.,Duke University |
Smith M.E.,University of Florida |
Nowak M.,University of Zürich |
Healy R.A.,University of Minnesota |
And 14 more authors.
PLoS ONE | Year: 2013
Truffles have evolved from epigeous (aboveground) ancestors in nearly every major lineage of fleshy fungi. Because accelerated rates of morphological evolution accompany the transition to the truffle form, closely related epigeous ancestors remain unknown for most truffle lineages. This is the case for the quintessential truffle genus Tuber, which includes species with socio-economic importance and esteemed culinary attributes. Ecologically, Tuber spp. form obligate mycorrhizal symbioses with diverse species of plant hosts including pines, oaks, poplars, orchids, and commercially important trees such as hazelnut and pecan. Unfortunately, limited geographic sampling and inconclusive phylogenetic relationships have obscured our understanding of their origin, biogeography, and diversification. To address this problem, we present a global sampling of Tuberaceae based on DNA sequence data from four loci for phylogenetic inference and molecular dating. Our well-resolved Tuberaceae phylogeny shows high levels of regional and continental endemism. We also identify a previously unknown epigeous member of the Tuberaceae - the South American cup-fungus Nothojafnea thaxteri (E.K. Cash) Gamundí. Phylogenetic resolution was further improved through the inclusion of a previously unrecognized Southern hemisphere sister group of the Tuberaceae. This morphologically diverse assemblage of species includes truffle (e.g. Gymnohydnotrya spp.) and non-truffle forms that are endemic to Australia and South America. Southern hemisphere taxa appear to have diverged more recently than the Northern hemisphere lineages. Our analysis of the Tuberaceae suggests that Tuber evolved from an epigeous ancestor. Molecular dating estimates Tuberaceae divergence in the late Jurassic (~156 million years ago), with subsequent radiations in the Cretaceous and Paleogene. Intra-continental diversification, limited long-distance dispersal, and ecological adaptations help to explain patterns of truffle evolution and biodiversity. © 2013 Bonito et al.
Von Muller A.R.,Instituto Nacional de Tecnologia Agropecuaria |
Renison D.,Institute Investigaciones Biologicas y Tecnologicas |
Cingolani A.M.,Instituto Multidisciplinario Of Biologia Vegetal
Rangeland Journal | Year: 2017
Few studies addressing drivers of cattle selectivity focus on the combination of ecological (biotic and abiotic) and management factors such as rotational systems, paddock sizes and paddock shapes. As a consequence, it is difficult to prioritise management practices integrating information of different driving factors. In a heterogeneous mountain rangeland in Central Argentina we established a total of 419 square study plots of 1ha located in 18 paddocks with differing sizes, shapes and cattle grazing management. Plots were small samples of landscapes, covering all existing variability in vegetation and physiography. For each plot we estimated the annual cattle use, average seasonal cattle density, forage types and abiotic characteristics. We used general linear models to show that selectivity was mainly driven by biotic variables. Cattle selected landscapes dominated by short palatable plants, but the strength of this influence differed among paddocks. Selectivity was strongest in paddocks with low abundance of lawns dominated by short palatable plants and low annual stocking rate. As stocking rate and the availability of lawns increased, selectivity strength decreased. Abiotic variables had far less influence than biotic variables, showing that cattle tended to avoid rough landscapes with steep terrain in the wet-warm season; and to be attracted by permanent water sources during the dry-cold season. Seasonal stocking density and paddock size had no detectable influence on cattle selectivity and distribution. Paddock shape influenced distribution but not the strength of forage selectivity. We conclude that in our system, cattle selectivity is mainly driven by biotic factors, and the most effective methods of changing the consequent distribution pattern is by manipulating forage types and paddock shape. The role of stocking rate remains controversial as it was correlated with the proportion of lawns in the paddock. © Australian Rangeland Society 2017.
Hernandez M.L.,Centro Regional Of Investigaciones Cientificas Y Transferencia Tecnologica |
Dujardin J.P.,Institute Of Recherches Pour Le Developpement |
Gorla D.E.,Centro Regional Of Investigaciones Cientificas Y Transferencia Tecnologica |
Gorla D.E.,Instituto Multidisciplinario Of Biologia Vegetal |
Catala S.S.,Centro Regional Of Investigaciones Cientificas Y Transferencia Tecnologica
Revista da Sociedade Brasileira de Medicina Tropical | Year: 2015
Introduction: Insects of the subfamily Triatominae are vectors of Trypanosoma cruzi, the Chagas disease parasite, and their flying behavior has epidemiological importance. The flying capacity is strikingly different across and within Triatominae species, as well as between sexes or individuals. Many Triatoma infestans individuals have wings but no flying muscles. In other Triatominae species, no clear relationships were found between wing length and flying behavior. If wing presence or size is not reflective of the flying behavior, which other parts of the body could be considered as reliable markers of this important function? Methods: The genus Mepraia has exceptional characteristics with invariably wingless females and wingless or winged males. We calculated the porous surface exposed to odorant molecules to estimate the olfactory capacity of Mepraia spinolai. The head shape and thorax size were estimated using the geometric morphometric approach and traditional morphometric techniques, respectively. Results: Alary polymorphism in M. spinolai was significantly associated with consistent modification of the thorax size, head shape, and notable change in the estimated olfactory capacity. The macropterous individuals had a larger olfactory surface and thorax size and significantly different head shape compared to those of the micropterous individuals. Conclusions: We concluded that these structural changes could be associated with the flying potential of Triatominae. Thus, morphological attributes not found on wings could help determine the likely flying potential of the bugs. © 2015, Sociedade Brasileira de Medicina Tropical. All rights reserved.
Freire S.E.,Institute Botanica Darwinion |
Barboza G.E.,Instituto Multidisciplinario Of Biologia Vegetal |
Barboza G.E.,National University of Cordoba |
Cantero J.J.,Instituto Multidisciplinario Of Biologia Vegetal |
And 2 more authors.
Systematic Botany | Year: 2014
Famatinanthus, a new genus of Asteraceae (Mutisioideae, Onoserideae), is described and illustrated to accommodate one species from the Andes of Argentina, that was previously placed in Aphyllocladus, A. decussatus, as Famatinanthus decussatus comb. nov. The new genus is tentatively assigned to the tribe Onoserideae based on its shrubby habit, solitary radiate capitula, style rounded at the apex and dorsally papillose, and 2-3-seriate heteromorphic pappus. Famatinanthus is similar to Aphyllocladus but it is easily distinguished by the leafy, decussate branches with opposite leaves, multistoried T-trichomes, cream corollas, apiculate apical anther appendages, setuliferous achenes, terete stems, lack of secretory cavities, and pollen with a conspicuous mesoaperture and microechinate-rugulate exine. A key to the genera of the Onoserideae is presented. Affinities of the new genus with other genera of the tribes Gochnatieae, Hyalideae, and Stifftieae are also discussed. © Copyright 2014 by the American Society of Plant Taxonomists.
Chiarini F.E.,Instituto Multidisciplinario Of Biologia Vegetal |
Santinaque F.F.,Institute Investigaciones Biologicas Clemente Estable |
Urdampilleta J.D.,Instituto Multidisciplinario Of Biologia Vegetal |
Las Penas M.L.,Instituto Multidisciplinario Of Biologia Vegetal
Plant Systematics and Evolution | Year: 2014
In order to study the evolution of different cytogenetic characters in species of Solanum sect. Acanthophora in relationship to the known phylogeny for this group, the following techniques were used: CMA/DAPI chromosome banding; fluorescent in situ hybridization with probes for the 18-5.8-26S and the 5S rDNA genes in mitotic chromosomes; nuclear DNA quantification by flow cytometry. Depending on the species, 2-6 of the 12 basic chromosome pairs were identified. The heterochromatic banding patterns were shown to be species-specific. All species presented one chromosome pair bearing a 18-5.8-26S signal and one pair (rarely two) with a 5S signal, the two rDNA sites being non-syntenic. The techniques employed allowed us to establish two species groups within sect. Acanthophora: one with small, symmetric chromosomes, little heterochromatin and lower DNA content, and the other one with larger and more asymmetric chromosomes, more heterochromatin CMA+/DAPI- (associated with NOR or not) and a higher DNA content. An elevated karyotype asymmetry would be associated with a high amount of heterochromatin and a high DNA content. The trend within sect. Acanthophora would be towards a loss of heterochromatin, a reduction of chromosome size, and an increase in symmetry. © 2013 Springer-Verlag Wien.
Bonzani N.E.,Instituto Multidisciplinario Of Biologia Vegetal |
Bravi V.S.,National University of Cordoba |
Barboza G.E.,Instituto Multidisciplinario Of Biologia Vegetal
Caldasia | Year: 2011
Morphological and anatomical studies on the gynoecium and fruit of Mentha species (sect. Mentha L. and sect. Pulegium (Mill.) Coss. & Germ.) from Argentina were done using optic and scanning electronic microscope. Some novelties on the gynoecium, nectary histology, microsculpture of the nutlets, epicuticular waxes in the hilum and the morphology of the crystalloids are reported for the first time for Mentha. Four types of microsculpture on the surface of the nutlets were established. The results are evaluated from a taxonomical point of view for species delimitation. In addition, myxocarpy is reported for M. citrata, M. x piperita and M. spicata for the first time and its occurrence is discussed.
Poca M.,Instituto Multidisciplinario Of Biologia Vegetal |
Poca M.,National University of Cordoba |
Perez-Harguindeguy N.,Instituto Multidisciplinario Of Biologia Vegetal |
Perez-Harguindeguy N.,National University of Cordoba |
And 3 more authors.
Ecologia Austral | Year: 2014
Litters' chemical and green leaves' physical quality have been indicated as determinants of litter decomposition. The objective of this work was to analyze the relationship between litter decomposition and chemical quality and green leaves physical quality of 24 dominant species of mesic and humid highland grasslands, Córdoba, Argentina. In addition, we compared the pattern of association between these variables with that described for the lowland mountains of the same region. We measured litter decomposition through a common garden experiment with two retrieval dates (70 and 196 days). We measured labile compounds (nitrogen) and recalcitrant compounds (cellulose, hemicelluloses and lignin) as litter chemical quality indicators. Besides, we calculated from these indicators the fiber content (sum of recalcitrant compounds), the holocellulose/fiber proportion and the lignin:nitrogen, holocellulose:nitrogen and fber:nitrogen ratios. We measured the specific leaf area as a physical quality indicator of the green leaves. The decomposition increased mainly while the fber:nitrogen ratio decreased for both retrieval dates. Contrary to other works, the lignin content and the specific leaf area were not significantly associated to the decomposition. The relationships that we found in this work between decomposition and quality parameters are similar to the ones described by Vaieretti et al. (2005) for the species of the lowland mountains of Córdoba. This similitude, in spite of the differences in species composition, functional types and environmental variables, indicate a consistent chemical control over decomposition.
Bo M.L.,National University of Cordoba |
Carrizo Garcia C.,Instituto Multidisciplinario Of Biologia Vegetal
Grana | Year: 2015
The rocoto chili (Capsicum pubescens) is a species native to the highlands of South America, which is cultivated for its fruits. The species is regarded as self-compatible; however, self-incompatible strains and even a variable degree of self-incompatibility have been found. To characterise pollen grains and determine whether there is also variation in pollen performance and male fertility in the species, pollen morphology, cellular state, starch content, viability, longevity and germinability were analysed in plants obtained from the germplasm cultivated in Argentina. All the individuals studied were male fertile, showing a high percentage of vital pollen, capable of germinating in vitro. Some pollen features were uniform (e.g. exine sculpture, number of nuclei at maturity), but there were significant variations in pollen performance among the plants studied. © 2014, © 2014 Collegium Palynologicum Scandinavicum.
Pollice J.,National University of Cordoba |
Pollice J.,CONICET |
Marcora P.,CONICET |
Marcora P.,Instituto Multidisciplinario Of Biologia Vegetal |
And 2 more authors.
New Forests | Year: 2013
The expansion of tree species within a grassland-woodland matrix relies heavily on an abundant seed crop, which may be affected by many factors; among these, browsing by livestock has gone largely ignored. Here we explore how seed production is affected by tree size, grazing by large domestic herbivores and interannual climate fluctuations in a small-sized tree (Polylepis australis, Rosaceae), which dominates the remnant forests in the high mountains of central Argentina. Seed number and seed mass per tree were quantified in 100 different-sized trees located in areas with and without livestock. Using seed traps we also determined seed rain variation in 15 plots between 2005 and 2008. The estimated number of seeds per tree ranged from 0 to 224,000 and increased with tree height (power relation); for trees smaller than 354 cm in height, seed production was lower in areas with livestock and higher in areas without livestock. Mass per seed increased with tree height, with no significant livestock effect. The largest seed rain was recorded in 2008, probably due to growth of seed trees and not in response to climate. To promote seed production and forest expansion, livestock should be excluded from areas with small trees, such as forest edges. © 2012 Springer Science+Business Media B.V.
PubMed | Instituto Multidisciplinario Of Biologia Vegetal
Type: Journal Article | Journal: Mycologia | Year: 2012
Mycorrhizal fungi that form hypogeous sporocarps are an important component of the temperate forest soil community. In many regions, such as the Nothofagus forest in the Patagonian Andes, this group of fungi has been poorly studied. Here we examined the spring and autumn community composition of sequestrate fungi, based on sporocarp production in pure forests of Nothofagus dombeyi (evergreen) and N. pumilio (deciduous). We investigated the possible relationships between these communities and environmental factors over 2 y. The rarefaction curves and the minimal richness estimates converged at nearly the same level for each forest type, and the asymptotes suggested that the sampling effort was sufficient to capture most of the hypogeous sporocarp richness in these forest stands. In total 27 species were recovered. Basidiomycota, Ascomycota and Glomeromycota respectively accounted for nine, two and one genera. Species richness of hypogeous sporocarps varied in relation to forest type but not to season (fall and spring), whereas sporocarp biomass varied according to an interaction between season and forest type. Species richness and sporocarp biomass were positively correlated with rainfall and negatively correlated with altitude. In addition sporocarp species richness was positively related to number of trees per transect. We found that two different forest stands, each dominated by different species of Nothofagus, exhibited different hypogeous sporocarp communities.