Dendrochronological potential of Copaifera lucens Dwyer (Fabaceae): endemic species of a hotspot in the Atlantic Forest of Brazil.

2016

Diversity of new root nodule bacteria from Erythrina velutina Willd., a native legume from the Caatinga dry forest (Northeastern Brazil).

This study aims to evaluate the phenotypical characteristics of bacterial isolates from mulungu (Erythrina velutina Willd.) nodules and determinate their Box-PCR fingerprinting. All bacteria were evaluated by the following phenotypic characteristics: growth rate, pH change, colony color and mucus production. The bacterial isolates able to re-nodulate the original host were also evaluated regarding its tolerance to increased salinity and different incubation temperatures, ability to growth using different carbon sources, intrinsic antibiotic resistance and ?in vitro? auxin biosynthesis. The molecular fingerprints were set up using the Box-PCR technique and the isolates were clustered by their profiles. Among the 22 bacterial isolates obtained, eight were able to re-nodulate the original host. Among the nodule inducing isolates, some were tolerant to 1% of NaCl and 39° C and all of them metabolized the maltose, fructose, glucose, sucrose and arabinose, were resistant to rifampicin and produced auxin. The bacteria showed low genetic similarity among them and reference strains, which indicates the great genetic variability of the isolates. The results of this work are the first reports about the bacterial isolates able to nodulate this species. A more deep study of these bacteria may reveal the existence of isolates tolerant to environmental stresses and suitable as a future mulungu inoculant.

Methodology for climate risk assessment of maize intercropped with Brachiaria in the Cerrado of Brazil.

2015

Climate change and impacts on family farming in the North and Northeast of Brazil.

The starting point for this study was the consideration of future climate change scenarios and their uncertainties. The paper presents the global projections from the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) and compares them with regional scenarios (downscaling) developed by the Brazilian National Institute for Space Research (Instituto Nacional de Pesquisas Espaciais - INPE), with a focus on two main IPCC scenarios (RCP4.5 and RCP8.5) and two main global models (MIROC and Hadley Centre) for the periods 2011-2040 and 2041-2070. It aims to identify the main trends in terms of changes in temperature and precipitation for the North and Northeast regions of Brazil (more specifically, in the Amazon, semi-arid and cerrado biomes).

Climate change and irrigation water requirement at Jaguaribe river basin, semi-arid northeast of Brazil.

Summary: Climate change has a potential to impact rainfall, temperature and air humidity, which have relation to plant evapotranspiration and crop water requirement. The purpose of this research is to assess climate change impacts on irrigation water demand, based on future scenarios derived from the PRECIS (Providing Regional Climates for Impacts Studies), using boundary conditions of the HadCM3 submitted to a dynamic downscaling nested to the Hadley Centre regional circulation model HadRM3P. Monthly time series for average temperature and rainfall were generated for 1961-90 (baseline) and the future (2040). The reference evapotranspiration was estimated using monthly average temperature. Projected climate change impact on irrigation water demand demonstrated to be a result of evapotranspiration and rainfall trend. Impacts were mapped over the target region by using geostatistical methods. An increase of the average crop water needs was estimated to be 18.7% and 22.2% higher for 2040 A2 and B2 scenarios, respectively. Objective ? To analyze the climate change impacts on irrigation water requirements, using downscaling techniques of a climate change model, at the river basin scale. Method: The study area was delimited between 4º39?30? and 5º40?00? South and 37º35?30? and 38º27?00? West. The crop pattern in the target area was characterized, regarding type of irrigated crops, respective areas and cropping schedules, as well as the area and type of irrigation systems adopted. The PRECIS (Providing Regional Climates for Impacts Studies) system (Jones et al., 2004) was used for generating climate predictions for the target area, using the boundary conditions of the Hadley Centre model HadCM3 (Johns et al., 2003). The considered time scale of interest for climate change impacts evaluation was the year of 2040, representing the period of 2025 to 2055. The output data from the climate model was interpolated, considering latitude/longitude, by applying ordinary kriging tools available at a Geographic Information System, in order to produce thematic maps.

Future climate change impacts on maize production in the Cerrado of Brazil.

2015

Quality of Brazil nuts stored in forced aeration silos.

The traditional system of collection and storage of Brazil nut compromises seriously the quality of these almonds as it contributes to the high incidence of contaminants, like fungi of the genus Aspergillus, which can produce aflatoxins. In this study, the objective was to evaluate the influence of the storage period in studied conditions, on the physicochemical characteristics and on the microbiological contamination of Brazil nuts. The experimental was designed as completely randomized, considering as treatments the storage period (0 - control, 30, 60, 90, 120 and 150 days) with four replicates of 3 kg of Brazil nuts each. The samples were submitted to physicochemical and microbiological analysis. It was observed that almonds submitted to the storage had their moisture content reduced by 78.2% at 150 days of storage, however, this reduction was not fast enough to avoid surface contamination by filamentous and potentially aflatoxins producing fungi. The critical period of contamination occurred on the first 30 days of storage when there was an increase of the studied fungi, as well as B1 and total aflatoxin. The studied storage conditions were four times more effective in reducing the product moisture content than the traditional methods, however, pre-drying is necessary to avoid contamination of the product.

Genetic diversity of the forage peanut in the Jequitinhonha, São Francisco, and Paranã River valleys of Brazil.

Arachis pintoi and A. repens are legumes with a high forage value that are used to feed ruminants in consortium systems. Not only do they increase the persistence and quality of pastures, they are also used for ornamental and green cover. The objective of this study was to analyze microsatellite markers in order to access the genetic diversity of 65 forage peanut germplasm accessions in the section Caulorrhizae of the genus Arachis in the Jequitinhonha, São Francisco and Paranã River valleys of Brazil. Fifty-seven accessions of A. pintoi and eight of A. repens were analyzed using 17 microsatellites, and the observed heterozygosity (HO), expected heterozygosity (HE), number of alleles per locus, discriminatory power, and polymorphism information content were all estimated. Ten loci (58.8%) were polymorphic, and 125 alleles were found in total. The HE ranged from 0.30 to 0.94, and HO values ranged from 0.03 to 0.88. By using Bayesian analysis, the accessions were genetically differentiated into three gene pools. Neither the unweighted pair group method with arithmetic mean nor a neighbor-joining analysis clustered samples into species, origin, or collection area. These results reveal a very weak genetic structure that does not form defined clusters, and that there is a high degree of similarity between the two species.

Monitoring of glyphosate residues in herbicide tolerant soybeans from eight production areas of Brazil - 2005/2006 and 2006/2007 harvest seasons.

2008

Aroma profile of Cabernet Sauvignon tropical wines produced in Northeastern of Brazil.

2011

Resistance to Meloidogyne incognita, Meloidogyne javanica and Pratylenchus brachyurus in sunflower cultivars adapted to the tropical region of Brazil.

The continuous soybean-maize crop succession in the tropical region of Brazil has led to significant increases in the population size of root-knot (Meloidogyne incognita and M. javanica ) and root-lesion nematodes (Pratylenchus brachyurus), which make soils unsuitable for soybean cropping. A greenhouse study was conducted to identify sunflower genotypes adapted to the tropical region of Brazil and that are resistant to M. incognita, M. javanica and/or P. brachyurus . Two experiments for each nematode were conducted in a completely randomized design with six replicates. Gall index was calculated from visual scores (0?5) of gall intensity on roots for the root-knot nematode. Initial and final population density and reproduction factor were also measured for each nematode. Sunflower genotypes varied in resistance to the nematodes. Sunflower hybrids BRS 321 and BRS 323 were resistant to M. javanica and P. brachyurus and exhibited low gall index for M. incognita . The cultivars are good alternatives to using in the succession of soybean in nematode-infested areas of the tropical regions of Brazil. No sunflower genotype was identified as resistant to M. incognita and thus sunflower cropping is not indicated in areas infested with this nematode.

Satellite based multi-scale methods to support governance of Brazil's low-carbon agriculture (ABC Plan).

Brazil's Low Carbon Agriculture is one the initiatives that puts the climate in the agricultural agenda towards a more sustainable and adapted agriculture under global changes. Among the several practices listed and supported by the ABC Plan, zero tillage and integrated crop-livestock-forestry systems including the recovery of degraded pasture are the most relevant ones. The objective of this paper is to present the Geo-ABC Project, a procedure to monitor the implementation of the Brazil?s Low Carbon Agriculture (ABC Plan) and aiming at the development of remote sensing methods to monitor agricultural systems listed in the ABC Plan and adopted at local scale.