Salicylic acid and salicylic acid glucoside in xylem sap of Brassica napus infected with Verticillium longisporum

Salicylic acid (SA) and its glucoside (SAG) were detected in xylem sap of Brassica napus by HPLC–MS. Concentrations of SA and SAG in xylem sap from the root and hypocotyl of the plant, and in extracts of shoots above the hypocotyl, increased after infection with the vascular pathogen Verticillium longisporum. Both concentrations were correlated with disease severity assessed as the reduction in shoot length. Furthermore, SAG levels in shoot extracts were correlated with the amount of V. longisporum DNA in the hypocotyls. Although the concentration of SAG (but not SA) in xylem sap of infected plants gradually declined from 14 to 35 days post infection, SAG levels remained significantly higher than in uninfected plants during the whole experiment. Jasmonic acid (JA) and abscisic acid (ABA) levels in xylem sap were not affected by infection with V. longisporum. SA and SAG extend the list of phytohormones potentially transported from root to shoot with the transpiration stream. The physiological relevance of this transport and its contribution to the distribution of SA in plants remain to be elucidated

A coleção fotográfica de Marcel Gautherot

Considering contemporary Anthropologys debate around photography, there is a\ud keen interest in the understanding of one of the most important open to public consultation\ud photographic collections on 20th Century Brazil, that of Frenchman Marcel Gautherot (1910-\ud 1996). The collection comprises around 25,000 photographs, purchased in 1999 by Instituto\ud Moreira Salles and kept in its fund in the city of Rio de Janeiro. The text comments on the\ud photographers work, linked to documentary projects under the patronage of institutions such as\ud the Musée de l´Homme in Paris, at the end of the 1930s, and both the National Historic and\ud Artistic Patrimony Service and the Brazilian Folklore Defence Campaign, in Brazil, between the\ud years of 1940 -1960. Such commitments and interests define important thematic groupings in\ud the production and organisation of his personal photographic archive. A discussion about criteria and technical procedures adopted by the photographer is attempted, detailing series\ud and visual narratives about Brazilian cultures density. With the photographs purchase by the\ud IMS, the oeuvres aesthetic quality, now as an institutional collection, is highlighted. The collections\ud manners of preservation and conservation, reproduction and circulation are redefined

The Protein Phosphatase 7 Regulates Phytochrome Signaling in Arabidopsis

The psi2 mutant of Arabidopsis displays amplification of the responses controlled by the red/far red light photoreceptors phytochrome A (phyA) and phytochrome B (phyB) but no apparent defect in blue light perception. We found that loss-of-function alleles of the protein phosphatase 7 (AtPP7) are responsible for the light hypersensitivity in psi2 demonstrating that AtPP7 controls the levels of phytochrome signaling. Plants expressing reduced levels of AtPP7 mRNA display reduced blue-light induced cryptochrome signaling but no noticeable deficiency in phytochrome signaling. Our genetic analysis suggests that phytochrome signaling is enhanced in the AtPP7 loss of function alleles, including in blue light, which masks the reduced cryptochrome signaling. AtPP7 has been found to interact both in yeast and in planta assays with nucleotide-diphosphate kinase 2 (NDPK2), a positive regulator of phytochrome signals. Analysis of ndpk2-psi2 double mutants suggests that NDPK2 plays a critical role in the AtPP7 regulation of the phytochrome pathway and identifies NDPK2 as an upstream element involved in the modulation of the salicylic acid (SA)-dependent defense pathway by light. Thus, cryptochrome- and phytochrome-specific light signals synchronously control their relative contribution to the regulation of plant development. Interestingly, PP7 and NDPK are also components of animal light signaling systems

Arqueologia e história indígena no Pantanal

O artigo apresenta uma síntese dos dados arqueológicos sobre o Pantanal e o seu entorno, principalmente em Mato Grosso e Mato Grosso do Sul. Elaborado com base na noção de arqueologia como história indígena de longa duração, o artigo considera as trajetórias de estabelecimento e consolidação territorial da ocupação indígena regional, os processos de formação da configuração etnográfica encontrada pelos europeus e os impactos do colonialismo. O principal objetivo consiste em mostrar que a diversidade cultural característica do cenário etnográfico pantaneiro está associada à dinâmica histórica e cultural da ocupação indígena desde períodos anteriores à chegada dos conquistadores e colonizadores de origem europeia.The article presents an overview of the archaeological data on the Pantanal and its surrounding areas, mainly in Mato Grosso and Mato Grosso do Sul. Prepared based on the notion of archeology as long term indigenous history, the article considers the trajectories of territorial establishment and consolidation of the regional indigenous occupation, the formation processes of ethnographic setting found by Europeans and the impact of colonialism. The main objective is to show that cultural diversity characteristic of the Pantanal ethnographic scenario is associated with historical and cultural dynamics of indigenous occupation from periods prior to the arrival of the conquistadors and settlers of European origin

A arqueologia dos fermentados: a etílica história dos Tupi-Guarani

O consumo de bebidas fermentadas é geralmente negligenciado pela literatura arqueológica, que trata a questão como tema de interesse secundário (recreativo) na história das populações humanas. Entretanto, a literatura etnográfica das sociedades indígenas das terras baixas sul-americanas indica exatamente o oposto: é o alimento vegetal sólido e não alcoólico que tende a possuir um papel secundário na vida cotidiana e ritualística de diversos coletivos. Os dados arqueológicos aprofundam temporalmente essa relação entre o ser humano e os fermentados. Além disso, os vasos cerâmicos arqueológicos utilizados para o preparo e consumo desses fermentados são fundamentais para a compreensão de processos e eventos históricos que modelaram a dispersão de uma série de grupos pelo continente

Disease: A Hitherto Unexplored Constraint on the Spread of Dogs (Canis lupus familiaris) in Pre-Columbian South America

Although debate continues, there is agreement that dogs (Canis lupus familiaris) were first domesticated in Eurasia, spreading from there to other parts of the world. However, while that expansion already extended as far as Europe, China, and North America by the early Holocene, dogs spread into (and south of) the tropics only much later. In South America, for example, the earliest well attested instances of their presence do not reach back much beyond 3000 cal. BC, and dogs were still absent from large parts of the continent – Amazonia, the Gran Chaco, and much of the Southern Cone – at European contact. Previous explanations for these patterns have focused on cultural choice, the unsuitability of dogs for hunting certain kinds of tropical forest prey, and otherwise unspecified environmental hazards, while acknowledging that Neotropical lowland forests witness high rates of canine mortality. Building on previous work in Sub-Saharan Africa (Mitchell 2015) and noting that the dog’s closest relatives, the grey wolf (C. lupus) and the coyote (C. latrans), were likewise absent from South and most of Central America in Pre- Columbian times, this paper explores instead the possibility that infectious disease constrained the spread of dogs into Neotropical environments. Four diseases are considered, all likely to be native and/or endemic to South America: canine distemper, canine trypanosomiasis, canine rangeliosis, and canine visceral leishmaniasis caused by infection with Leishmania amazonensis and L. colombiensis. The paper concludes by suggesting ways in which the hypothesis that disease constrained the expansion of dogs into South America can be developed further