Electrophoresis(SDS-PAGE)as a Method for Screening Species of Passiflora Using Seed Proteins as Molecular Markers

Brazil is the center of diversity and dispersion of species of the genus Passiflora.Two species of passion fruit Passiflora tenuifila BRS VT(passiflora garlic)and another of Passiflora setacea BRS PC were used in this study.The plants were grown on the Embrapa Cerrados experimental farm.The fruits were washed,minimally cut and their constituents separated.Both species differed in the proportion of wet mass between husk,seed,and pulp.As expected,both species had a higher proportion of husks and seeds and a lower amount of pulp.A semi-purification procedure for the proteins present in the seeds and husks was described and the molecular aspects were analyzed by polyacrylamide gel electrophoresis(SDS-PAGE).The quantification of soluble proteins was performed using the Bradford method.The analysis of the soluble protein extracted from the seeds and husks showed that these values are up to 70 times higher for the seeds of P.tenuifila and 28.5 times for P.setacea,in the husks.It was verified that both species present a similar protein profile,observed by the intense and diverse bands found in the polyacrylamide gel,mainly in the range of 32 to 19 kDa.This work opens up an unexplored field of tracking bioactive proteins and/or peptides including forms of nanostructure systems that protect other bioactive molecules.The objective of this work was to present an analytical procedure to semi-purify seed proteins of two Passiflora species and use electrophoresis as an analysis tool for further screening of their protein profiles and selection of a molecular marker to differentiate them.

Soil Invertebrates in Different Land Use Systems： How Integrated Production Systems and Seasonality Affect Soil Mesofauna Communities

The soil mesofauna plays a role in organic matter comminution and decomposition, and can be used as bioindicators, since they are sensitive to soil management, vegetation and climate changes. Hence, this study aimed to evaluate mesofauna density and diversity in different land use systems to identify faunal relationships with soil properties, management and seasonality. The study area included five land use systems in Ponta Grossa municipality, Parana State： integrated crop-livestock （ICL）, integrated crop-livestock-forestry （ICLF）, grazed native pasture （NP）, Eucalyptus dunnii plantation （EU） and no-tillage （NT） cropping systems. In each system, eight soil samples for mesofauna were collected with Berlese funnels of 8 cm diameter along a transect in three replicate plots of 50 m × 100 m. For physical and chemical analysis, soil was sampled at five points per plot in two seasons： winter 2012 and autumn 2013. Data were statistically analyzed using ANOVA and Duncan＇s test （P 〈 0.05）, nonparametric statistics （when necessary） and redundancy analysis （RDA）. Diversity was calculated based on the group richness and Simpson index. The main mesofauna groups found were： Acarina, Collembola and Hymenoptera. Diplopoda, Enchytraeidae, Isopoda, Collembola, Hemiptera, Hymenoptera and Coleoptera larvae were more abundant in autumn than winter. Soil moisture was the main factor responsible for higher mesofauna abundance in autumn. Integrated production systems, especially ICLF had similar invertebrate community abundance and composition with EU, while NT favored Oribatid mites, although the use of insecticides, herbicides and fungicides reduced total mesofauna density. Most correlations between mesofauna and physical-chemical attributes in the winter were not observed in the autumn and vice versa, revealing that there are more factors involved in regulating soil mesofauna distribution.

Do Bt Transgenic Events Alter the Phenotypic Stability of Maize Hybrids?

Transgene insert location in the genome through different methods is random. Thus, alterations in the expression of desired trait may occur, as well as alterations in the expression of other characteristics of receptor plant. The purpose of this study was to compare Bt transgenic maize hybrids and the respective conventional isogenic hybrid in relation to adaptability and phenotypic stability. Field trails were set up in four locations of Minas Gerais, Brazil (Campo do Meio, Lavras, Madre de Deus and Paragua?u). A randomized complete block design was used, with three replications, and the treatment structure was a factorial 6 × 2, with six hybrids in the transgenic and conventional versions. Plant and ear height and grain yield were evaluated. To estimate stability, the Anicchiarico, Wricke and AMMI methodologies were used. Grain yield and ear height of the transgenic hybrids and their respective conventional isogenic hybrid did not differ. There are differences in the phenotypic stability between transgenic hybrids with Bt technology and their counterpart conventional isogenic hybrid.

Estimates for Carbon Stocks in Soil under Humid Grassland Areas in the Federal District of Brazil

The soils that lay below humid ecosystems are characterized as being significant holders of carbon. Because of the great susceptibility of this type of environment to anthropic changes, expressive quantities of carbon stored in the soil can be released into the atmosphere. In the Cerrado biome (Brazil), only a few types of vegetation have had carbon storage levels in their soil estimated. The main purpose of this study was to obtain basic quantitative parameters for carbon storage and to identify the general aspects of soil in regions where there exists Humid Grasslands (Campo Limpo úmido), a kind of humid area phytophysiognomy found in the Cerrado. We selected 6 regions of the Federal District with this kind of vegetation formation, characterized by low anthropic impact and located either in the interior or in the proximity of specially protected areas. In each one of the sampled regions, we marked a transect with 4 equidistant points and collected material at 7 different levels of depth: 0 - 5, 5 - 10, 10 - 20, 20 - 30, 30 - 40, 40 - 50 and 50 - 60 cm. We obtained 168 samples, with 84 related to Humid Grassland areas in gleysols and 84 samples related to areas in plinthosols—types of soil dominant in this environment. We determined the texture, bulk density and concentration of nitrogen and carbon at each depth. The average concentration of carbon for Humid Grassland areas was 55.19 g.kg-1, with an average of 61.65 g.kg-1 for Gleysols and 48.73 g.kg-1 for Plinthosols. The soil samples displayed distinct textural differences between gleysols and plinthosols. There were no significant differences in soil density (0.75 kg.dm-3 for Gleysols and 0.72 kg.dm-3 for Plinthosols). The average concentration of nitrogen was 20.66 g.kg-1, with 23.98 g.kg-1 for Gleysols and 17.34 g.kg-1 for Plinthosols. The average carbon storage for Humid Grassland areas, down to 60 cm deep, was 244.17 mg C ha-1 and the total estimated stock for these areas in the Federal District was 206.71 Gg.C. In general, the samples obtained in gleysols showed a carbon content and nitrogen level superior to those in plinthosols, although a greater sampling effort is needed to confirm the differences observed. The density values of stored carbon in the soil beneath Humid Grassland areas proved to be superior to those values observed for other types of vegetation typical for the Cerrado environment.

Morphological traits explain the individual position within resource-consumer networks of a Neotropical marsupial

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions.We tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian savanna.Individuals with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet season.The relationship between individuals'position in the network and body traits,however,was independent of season.We propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological constraints.Smaller/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more specialized.Moreover,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.

A remote sensing approach to estimate the load bearing capacity of soil

Preconsolidation pressure(σp)of soil can be considered as an indicator of the Load Bearing Capacity(LBC),which is the tolerated surface pressure before compaction,often caused by the traffic of agricultural machinery.In this pioneering study,a remote sensing approach was introduced to estimate LBC throughσp from soils of the“Rio Preto”Hydrographic Basin,Bahia State,Brazil,in a monthly time lapse from 2016 to 2019.Traditionally,σp is measured by a laborious and time demanding laboratory analysis,making it unfeasible to map large areas.The innovative methodology of this work consists of combining active–passive satellite data on soil moisture and pedotransfer functions of clay content and water matric potential to obtain geo-located estimates ofσp.Estimates were analysed under different classes of soil use,land cover and slope;95%confidence intervals were built for the time series of mean values of LBC for each class.The overall seasonal variation in LBC estimates is similar in areas with annual crops,grasslands and natural vegetation,and flat areas are less affected by soil moisture variations over the year(between seasons).LBC decreased,in general,at about 0.5%a year in flat areas.Therefore,these areas demand attention,since they occupy 86%of the Basin and are mostly subjected to agricultural soil management and surface pressure by heavy machinery.

Agronomic evaluation of Herbaspirillum seropedicae strain ZAE94 as an inoculant to improve maize yield in Brazil

Diazotrophic bacteria applied as a seed inoculant can improve the grain yield of several crops including maize. The current study aimed to test the agronomic efficiency and contribution of biological nitrogen fixation(BNF) of the endophytic diazotroph Herbaspirillum seropedicae strain ZAE94 to maize under field conditions. Eighteen field assays were conducted in four different locations during consecutive years on two hybrids and two varieties of maize in a random block design with four replicates using a peat-based inoculant. The inoculant containing the ZAE94 strain was applied without nitrogen(N)fertilization or with 40 kg N ha^(-1) and was compared to the application of 40 and 80 kg N ha^(-1) without inoculation. Crop productivity and N accumulation in the grain were evaluated in addition to ^(15)N natural abundance(δ^(15)N) to evaluate BNF in the treatments without N fertilization. Fertilization at 40 kg N ha^(-1) plus bacterial inoculation produced crop yields similar to the treatment with 80 kg N ha^(-1) and increased grain N content, especially in the off-season with 40 kg N ha^(-1). The inoculation treatments showed lower δ^(15)N values than the non-inoculated treatments, which was most evident in the off-season. The BNF contributed about 30% of N accumulated in plants inoculated with ZAE94. On average, 64% of the N fertilized plots showed an increase of the parameters evaluated in the inoculated treatments, compared with the control. Inoculation also increased root length, root volume, and leaf area, and these parameters were positively correlated with plant weight using a hydroponic assay. This study revealed that the application of H. seropedicae inoculant increased the amount of N in plants owing to BNF, and there is a better chance of yield response to inoculation under low N fertilizer application in the off-season.

Use of the Nitrogen Index to assess nitrate leaching and water drainage from plastic-mulched horticultural cropping systems of Florida

Water quality in Florida is significantly impacted by nitrate(NO_(3)-N)leaching losses from agriculture in a large part of the state.Horticultural crops are planted across large areas of Florida on coarse sandy soils with low soil water retention and soil organic matter,increasing the potential for NO_(3)-N leaching.Nitrate leaching losses from the root zone of vegetable cropping systems can negatively impact groundwater.New tools such as the Nitrogen Index(N-Index)are able to quickly assess N use efficiency and losses via NO_(3)-N leaching from agricultural systems.Furthermore,the N-Index provides technical information about N losses pathways tied to agricultural management practices with a great level of confidence;this information has been used by researchers,growers and policymakers as a decision support system.However,the current version of the NIndex that has been used for different field crops has not been calibrated to be used in plastic-mulched horticultural cropping systems.The aim of this work was to calibrate and validate the N-Index for plasticmulched horticultural cropping systems of Florida.This study found that the N-Index tool accurately identified and ranked the risk of N losses in the evaluated horticultural systems.The N-Index was calibrated for Florida's plastic-mulched horticultural cropping systems using a sensitivity analysis.The adjusted N-Index was validated using compiled data of vegetables grown under plastic mulching systems during three consecutive seasons.Results from these studies suggest that the N-Index can be an easy-to-use tool capable of assessing nitrogen management practices for vegetable systems.The tool can be used to guide nutrient managers in the implementation of best nitrogen management practices that could contribute to reduced NO_(3)-N leaching losses from vegetable systems in Florida,contributing to a smaller environmental footprint and conservation of water quality.