It is well-documented that phytochromes can control plant growth and development from germination to flowering. Additionally, these photoreceptors have been shown to modulate both biotic and abiotic stress. This has l...It is well-documented that phytochromes can control plant growth and development from germination to flowering. Additionally, these photoreceptors have been shown to modulate both biotic and abiotic stress. This has led to a series of studies exploring the molecular and biochemical basis by which phytochromes modulate stresses, such as salinity, drought, high light or herbivory. Evidence for a role of phytrochromes in plant stress tolerance is explored and reviewed.展开更多
Aims The coastal Brazilian rainforest on white-sand(restinga)ranks among the most fragmented forest types in the tropics,owing to both the patchy distribution of sandy soils and widespread coastal development activiti...Aims The coastal Brazilian rainforest on white-sand(restinga)ranks among the most fragmented forest types in the tropics,owing to both the patchy distribution of sandy soils and widespread coastal development activities.Here we study the environmental and evolutionary determinants of a forest tree assemblage at a single restinga forest in Southeastern Brazil.We also explore the ability of competing hypotheses to explain the maintenance of species diversity in this forest type,which includes contrasting extremes of edaphic conditions associated with flooding stress.Methods The study was conducted in a white-sand forest permanent plot of 10.24 ha on the coastal plain of Southeastern Brazil.This plot was divided into 256 quadrats of 20×20 m,which were classified into two main edaphic habitats(flooded and drained).Trees with a diameter≥1 cm at breast height were identified.We assembled DNA sequence data for each of the 116 morphospecies recognized using two chloroplast markers(rbcL and matK).A phylogenetic tree was obtained using the maximum likelihood method,and a phylogenetic distance matrix was produced from an ultrametric tree.We analyzed similarity in floristic composition and structure between habitats and related them to cross-plot distances using permutation procedures.Null model torus shift simulations were performed to obtain a statistical significance level for habitat association for each species.The phylogenetic structure for the two habitats and for each 20×20 m quadrat was calculated using the mean phylogenetic distance weighted by species abundance and checked for significance using the standardized effect size generated by 5000 randomizations of phylogenetic tip labels.Important Findings Our results indicate that partitioning among edaphic habitats is important for explaining species distributions and coexistence in restinga forests.Species distributions within the plot were found to be non-random:there was greater floristic similarity within than between habitats,and>40%of the more abundant spec展开更多
Glycine max is a photoperiodic short-day plant and the practical consequence of the response is latitude and sowing period limitations to commercial crops. Genetic and physiological studies using the model plants Arab...Glycine max is a photoperiodic short-day plant and the practical consequence of the response is latitude and sowing period limitations to commercial crops. Genetic and physiological studies using the model plants Arabidopsis thaliana and rice （Oryza sativa） have uncovered several genes and genetic pathways controlling the process, however information about the corresponding pathways in legumes is scarce. Data mining prediction methodologies, including multiple sequence alignment, phylogeneUc analysis, bioinformaUcs expression and sequence motif pattern identification, were used to identify soybean genes involved in day length perception and photoperiodic flowering induction. We have investigated approximately 330 000 sequences from open-access databases and have identified all bona fide central oscillator genes and circadian photoreceptors from A. thaliana in soybean sequence databases. We propose a working model for the photoperiodic control of flowering time in G. max, based on the identified key components. These results demonstrate the power of comparative genomics between model systems and crop species to elucidate the several aspects of plant physiology and metabolism.展开更多
Background： This study evaluated the impact of hormonal modulation at the onset of proestrus on ovarian response and uterine gene expression of beef cows.Methods： A total of 172 anestrous beef cows were assigned to ...Background： This study evaluated the impact of hormonal modulation at the onset of proestrus on ovarian response and uterine gene expression of beef cows.Methods： A total of 172 anestrous beef cows were assigned to one of four groups according to the treatment with estradiol cypionate（ECP） and/or equine chorionic gonadotropin（eCG） [CON（n = 43）, ECP（n = 43）, eCG（n = 44）and ECP ＋ eCG（n = 42）].Results： ECP-treated cows（ECP and ECP ＋ eCG groups） presented greater occurrence of estrus（44.6% vs. 65.4%; P = 0.01） and pregnancy per AI [47.1% vs. 33.3%; P = 0.07], but similar progesterone（P4） concentration at subsequent diestrus than cows not treated with ECP（CON and eCG groups）. Nonetheless, eCG-treated cows（eCG and ECP ＋ eCG groups） presented larger follicle at timed AI（12.6 ± 0.3 vs. 13.5 ± 0.3 mm; P = 0.03）, greater ovulation rate（96.5%vs. 82.6%; P = 0.008） and greater P4 concentration at d 6（3.9 ± 0.2 vs. 4.8 ± 0.2 ng/mL; P = 0.001） than cows not treated with eCG（CON and ECP groups）. Next, cows with a new corpus luteum 6 d after TAI were submitted to uterine biopsy procedure. Uterine fragments [CON（n = 6）, ECP（n = 6）] were analyzed by RNA-Seq and a total of 135 transcripts were differentially expressed between groups（73 genes up-regulated by ECP treatment）. Subsequently,uterine samples were analyzed by q PCR（genes associated with cell proliferation）. ECP treatment induced greater abundance of PTCH2（P = 0.07） and COL4 A1（P = 0.02）, whereas suppressed EGFR（P = 0.09） expression. Conversely, eCG treatment increased abundance of HB-EGF（P = 0.06）, ESR2（P = 0.09）, and ITGB3（P = 0.05）, whereas it reduced transcription of ESR1（P = 0.05）. Collectively, supplementation with ECP or eCG at the onset of proestrous of anestrous beef cows influenced ovarian responses, global and specific endometrial gene expression.Conclusion： Proestrus estradiol regulate the endometrial transcriptome, particularly stimulating pr展开更多
Separately, it is well-documented that phytochromes (phys), gibberellin (GA) and abscisic acid (ABA) strongly control the seed germination in tomato. However, we hipothesized that phys interact with GA or ABA during t...Separately, it is well-documented that phytochromes (phys), gibberellin (GA) and abscisic acid (ABA) strongly control the seed germination in tomato. However, we hipothesized that phys interact with GA or ABA during this response. Thus, we make an analysis of seed germination of ABA deficient (sit), GA constitutive response (pro), phytochrome deficient (au) mutants as well as, specially, au sit and au pro double mutants of tomato?incubated in the dark or light conditions during 120 h [12 h intervals (i)]. Compared to au, which severely?reduced percentage germination (Gi%) and pro, which did not alter Gi%, au pro showed in the light enhanced Gi% and germination speed index (GSI) besides the reduced average germination time (AGT). Moreover, in the dark, germination of au pro was similar to pro. These results indicate that the mechanisms by which GA modulate germination in tomato are light dependent through the phy signaling, whereas intermediary values of Gi%, GSI and AGT in dark and light of au sit compared to au and sit single mutants indicate an additive effect of the au and sit mutations, suggesting that ABA and phy may act through the parallel signaling pathway.展开更多
Each year, ethanol production is increasing in Brazil, consequently, the generation of byproducts as well. Among these, the vinasse stands out. With polluting power a hundred times greater than domestic sewage and hig...Each year, ethanol production is increasing in Brazil, consequently, the generation of byproducts as well. Among these, the vinasse stands out. With polluting power a hundred times greater than domestic sewage and high concentration of minerals, vinasse is generated in large volumes. Because of these characteristics, it is widely used in fertirrigation. However, it is composed of about 97% water, inflating the cost of the transport from the plant to the field. For these reasons, removing water from the vinasse and the consequent concentration of solids is an alternative management and application of this by-product. This project aimed to analyze the efficiency of various physical and chemical processes in the removal of water from the vinasse.展开更多
A model based on Watson’s power law for the species-area relationship predicts that full global warming, projected up to the year 2050, could provoke the disappearance of roughly one-quarter of existing species. Here...A model based on Watson’s power law for the species-area relationship predicts that full global warming, projected up to the year 2050, could provoke the disappearance of roughly one-quarter of existing species. Here, an alternative approach is worked out, based on the combination of two ecology laws: Taylor and Watson’s power laws, where the former relates species variability with their mean abundance. Just how severely global warming would affect not only the number but the diversity of the surviving species is addressed by this approach, while at the same time giving indications for the post-disaster fate of the remaining species (extinction or recovery).展开更多
The growth of a tree or a forest settlement is of great value to a forest enterprise, because many decisions are directly dependent of this information, for instance, determining the optimal cutting age. This study ai...The growth of a tree or a forest settlement is of great value to a forest enterprise, because many decisions are directly dependent of this information, for instance, determining the optimal cutting age. This study aims to apply a new class of models to fit growth curves for diameter and height of Eucalyptus grandis X Eucalyptus urophylla seedling data. Data were collected from a trial conducted in a green house at the Natural Resources Department at School of Agriculture, Botucatu, S?o Paulo, Brazil. The experiment’s design was completely randomized with eight treatments and four replications. In this trial, the growth variables referring to the height and the diameter were evaluated, being measured five and four times, respectively. The methodology was carried in a mixed longitudinal model using a new approach based on Box-Cox Normal (BCN) distribution, and comparisons with this model were made assuming normality of the data. The results revealed that the BCN mixed model provided similar results to the standard model in order to estimate growth curves;however, the BCN model was the best result according to Akaike criterion, considering the slight asymmetry in the data set. This approach is of great interest in case of outliers and robust procedures for parameter estimation.展开更多
Drought is considered the main environmental factor limiting productivity in eucalyptus plantations in Brazil. However, recent studies have reported that exposure to water deficit conditions enables plants to respond ...Drought is considered the main environmental factor limiting productivity in eucalyptus plantations in Brazil. However, recent studies have reported that exposure to water deficit conditions enables plants to respond to subsequent stresses. Thus, this study investigates the ecophysiological acclimatization of eucalyptus clones submitted to recurrent water deficit cycles. Eucalyptus seedlings were submitted to three recurrent water deficit cycles and anatomical, morphological and physiological changes were analyzed. The results were:(1) Eucalyptus seedlings responded to water deficits by directing carbohydrates to root and stem growth;(2) Size and number of stomata were reduced;(3) Stomatal conductance decreased which allowed the plants to reduce water losses through transpiration,increasing instantaneous water use efficiency;(4) The relationship between gas exchanges and available water contents allowed the seedlings to uptake the retained soil water athigher tensions;and,(5) Physiological recovery from subsequent water deficits became faster. As a result of these changes, the eucalyptus seedlings recovered from the same degree of water stress more rapidly.展开更多
The number workable days (NWD) for agricultural field operations is of great importance for sizing agricultural machinery fleets. This is especially pivotal for sugarcane harvest, which extends from 8 to 10 months/yea...The number workable days (NWD) for agricultural field operations is of great importance for sizing agricultural machinery fleets. This is especially pivotal for sugarcane harvest, which extends from 8 to 10 months/year. In light of this, the current study aimed at defining criteria for obtaining the NWD for rational sugarcane harvest at different sites in the state of São Paulo, southern Brazil, taking into account both a general and a specific criteria. For this purpose, data from harvest interruption of 30 sugar mills in southern Brazil throughout periods ranging from two to five years were used. The following variables were tested as criteria for defining harvest interruption: minimum precipitation (PREC);soil water holding capacity (SWHC);and the limit of the ratio between actual soil moisture (SM) and SWHC. Based on such a specific criterion ascribed to each site along with a general criterion, NWD maps were prepared for the state of São Paulo, Brazil. The results showed that there were variations from the definition criteria of NWD at the different sites in the state. However, the use of a general criterion for harvest interruption, based on PREC ≥ 3 mm, SWHC = 40 mm and SM/SWHC ≥ 90%, provided accurate results. During the validation of these criteria, the NWD maps generated from the individual criterion proposed for each site resulted in an average error of 24.9 days/year, whereas the map generated from the general criterion culminated in an average error of 4.4 days/year.展开更多
Eucalyptus benthamii is a forest species of economic interest that has difficulty with seed production and also is considered to have difficulty with adventitious rooting using propagation techniques, such as cutting ...Eucalyptus benthamii is a forest species of economic interest that has difficulty with seed production and also is considered to have difficulty with adventitious rooting using propagation techniques, such as cutting or mini-cutting. We aimed to assess the adventitious rooting percentage under different storage times in low temperatures and at various IBA （indole-3-butyric acid） concentrations to determine the optimal time of permanence for rooting Eucalyptus benthamii minicuttings in a greenhouse. Shoots collected from mini-stumps cultivated in a semi-hydroponic system were used to obtain the mini-cuttings. For the first experiment, the mini-cuttings were stored at 4℃ for 0 （immediate planting）, 24, 48, 72, 96 and 120 h. The second experiment evaluated the rooting dynamic to determine the optimal time of permanence for minicuttings in a greenhouse. The basal region of the mini-cutting was treated with various IBA solutions： 0 （free of IBA）, 1,000, 2,000, 3,000 and 4,000 mg.L^-1. Every seven days （0 （immediate planting）, 7, 14, 21 and 28 days）, destructive sampling of the mini-cuttings was performed to evaluate the histology of the adventitious rooting. Eucalyptus benthamii minicuttings should be rooted immediately after the collection of the shoots. The 2,000 mg.L^-1 IBA concentration induced a greater speed and percentage of adventitious rooting, and an interval of 35 to 42 days was indicated for permanence of the mini-cuttings in the greenhouse. Expo- sure to low temperature induced adventitious root formation with diffuse vascular connections.展开更多
Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram...Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram（4-amino-3,5,6-trichloropicolinic acid） at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose（control,2%,4% and 6%）.Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells.展开更多
Different global agendas have discussed the role of soils in mitigating and reducing global problems related to climate change,food security,biodiversity and erosion,among others.With this in mind,the aim was to draw ...Different global agendas have discussed the role of soils in mitigating and reducing global problems related to climate change,food security,biodiversity and erosion,among others.With this in mind,the aim was to draw up an overview of the main soil agendas in Europe and Brazil,analysing their impact on the establishment of legal frameworks for soil use and conservation.In Brazil,pastures are seen as an important alternative for converting degraded areas into ecosystem services.To this end,a literature review was carried out using databases on the Scopus,Web of Science,Science Direct and Scielo platforms,as well as consulting documents from the European Union Missions in Horizon Europe and Brazilian legislation on the subject.In a pilot river basin,the Potential for Conservation Use(PCU)method was applied,which is used in Brazil to assess the impacts of different uses on the natural capital of soils,serving as a metric to guide public soil conservation policies.It was concluded that,on the European scene,discussions on soils have taken place in an integrated and organised way,with actions to mobilise different players in society.In Brazil,even though there are important legal frameworks,actions are still restricted and disjointed,pointing to the need for progress in soil governance.In both scenarios,there is a need for scientifically validated metrics at regional scales that can contribute to a harmonised database capable of subsidising the development of efficient public policies to advance soil conservation at a global level.展开更多
The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with ...The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with high nutrient content. The purpose of this study was to assess the effects of foliar applications of calcium and molybdenum on yield and seed physiological potential in common bean plants. A randomized block design was implemented, with the treatments fixed in a factorial scheme: two molybdenum rates (with or without) and four calcium rates, with four replications. The calcium rates applied on the leaves were 0, 150, 300 and 600 g·ha-1 for the first year of the investigation (2005) and 0, 300, 600 and 900 g·ha-1 for the second year (2006). In both years, the molybdenum rates applied on the leaves were 0 g·ha-1 (without) and 75 g·ha-1 (with). The results showed that the foliar calcium application, with or without molybdenum, did not improve yield. Foliar application of calcium alone improved seed physiological potential in common bean plants when applied at the full bloom stage.展开更多
During the industrial fermentation process in the production of fuel ethanol, yeasts are subject to several stressing conditions. The survival and the permanence of strains introduced in the process correlate with the...During the industrial fermentation process in the production of fuel ethanol, yeasts are subject to several stressing conditions. The survival and the permanence of strains introduced in the process correlate with the capability of these yeasts in resisting to physical and chemical stresses, as well as their recovering ability to compete with contaminating micro-organisms commonly present in this industrial process. We aim at the selection of Saccharomyces cere visiae strains having this capability and ability. In this sense, cultivations of strains with industrial interest were irradiated with gammas ray at a wide dose interval. Growing curves for the strains were analyzed by means of their relative growth, a new concept here introduced, which allows a better understanding of the growing and recovering processes following radiative stress. It was found that gamma radiation could be used as an alternative method to quantify growing capabilities of S. cerevisiae strains under stressing conditions. It was also shown that this radiological method could be utilized as an additional procedure to select best robust industrial strains. This radiological method simplifies traditional analysis of strain viability, by avoiding the great number of necessary and consecutive fermentation assays.展开更多
The Brazilian citrus chain is comprised by an upstream farm sector, made up of numerous heterogeneous （by size and technology） farm units serviced by input suppliers, and a downstream segment consisting of a small n...The Brazilian citrus chain is comprised by an upstream farm sector, made up of numerous heterogeneous （by size and technology） farm units serviced by input suppliers, and a downstream segment consisting of a small number of processing industries. Our study examines the behavior of citrus pricing along this supply chain, focusing on the relationship between orange juice prices established in international markets and orange fruit prices paid to Brazilian farmers. Results indicate that the price of orange fruit is fundamentally linked to the price of its juice, regardless of data source considered for testing. Evidence was found indicating that there is asymmetry of price transmission within the Brazilian orange sector, with juice price increases being transmitted to the farmer in smaller proportions than juice price decreases. The results of our study did not give a particularly strong indication of the cause of this price asymmetry.展开更多
Considering that the pyroligneous liquor obtained from pyrolysis of various types of biomass has antiviral activity, the main objective of the present study was to evaluate the antimicrobial action of the methanolic f...Considering that the pyroligneous liquor obtained from pyrolysis of various types of biomass has antiviral activity, the main objective of the present study was to evaluate the antimicrobial action of the methanolic fraction extracted from bamboo （Dendrocalamus asper） pyroligneous liquor in relation to Escherichia coli and Staphylococcus aureus bacteria. The pyroligneous liquor was recovered by laboratorial bamboo pyrolysis at 350 °C and then fractioned by liquid-liquid separation with methanol and hexane. After solvent evaporation, we collected the methanolic extract, which was later diluted in methanol and used in the diffusion disc assay of E. coli and S. aureus at concentrations of 0.125, 0.500, 0.750 and 1.000 mg. Through GC/MS analysis, it was possible to qualitatively identify 92 chemical compounds in the methanolic fraction. Treatment with the methanolic fraction inhibited cellular growth and caused a variety of morphological variations in size as well as deformities in the bacterial cell walls, establishing an antimicrobial activity profile. This finding supports the National Policy for Incentives for Sustainable Management and Cultivation of Bamboo （PNMCB） and has benefits to the society and environment as a whole, as it demonstrates the possibility of adding value to a byproduct of pyrolysis.展开更多
Background: With the objective of increasing knowledge on biomass and carbon stocks, and thus improving the accuracy of published estimates, the present study explored wood density and carbon concentration of coarse w...Background: With the objective of increasing knowledge on biomass and carbon stocks, and thus improving the accuracy of published estimates, the present study explored wood density and carbon concentration of coarse woody debris (diameter≥10) by decay class in a Seasonal Semi-deciduous Forest (SSF) area in the Atlantic Rain Forest and in a Cerrado sensu-stricto (CSS) area (Brazilian savanna), in Brazil. Two strata were identified in each area and ten sampling units were systematic located in each stratum. Data were collected according to the line intersect sampling method. Each tallied element, the diameter, length, and perpendicular width were recorded at the transect intersection point. Each element was classified into a decay class, and the species was identified when possible. Sample discs were cut from each element, from which cylindrical samples were extracted and oven-dried to determine density. These cylinders were milled and analyzed using a LECO-C632 to determine carbon concentration as percentage of mass. Results: In both areas, wood density decreased as the decay class increased. For SSF the mean carbon concentration of all analyzed samples was 49.8% with a standard deviation of 3.3, with a range of 27.9–57.0% across 506 observations. For CSS the general mean was 49.6% with a standard deviation of 2.6, with a range of 31.2–54.5% over 182 observations. Carbon concentration barely change between decay classes. Carbon stock was estimated at 3.3 and 0.7 MgC/ha for the SSF and the CSS, respectively. Similar results were obtained when using a 50% conversion constant. Conclusions: The present study concludes that wood density decreases as the woody debris becomes more decomposed, a pattern found in many previous studies. The carbon concentration, however, barely changes between decay classes, and that result is consistent with most of the literature reviewed. Our carbon concentrations are very close to the 50% used most commonly as a conversion factor. We strongly recommend that future studies of CWD e展开更多
Background:The success of different species of ruminants in the colonization of a diverse range of environments is due to their ability to digest and absorb nutrients from cellulose,a complex polysaccharide found in l...Background:The success of different species of ruminants in the colonization of a diverse range of environments is due to their ability to digest and absorb nutrients from cellulose,a complex polysaccharide found in leaves and grass.Ruminants rely on a complex and diverse microbial community,or microbiota,in a unique compartment known as the rumen to break down this polysaccharide.Changes in microbial populations of the rumen can affect the host’s development,health,and productivity.However,accessing the rumen is stressful for the animal.Therefore,the development and use of alternative sampling methods are needed if this technique is to be routinely used in cattle breeding.To this end,we tested if the fecal microbiome could be used as a proxy for the rumen microbiome due to its accessibility.We investigated the taxonomic composition,diversity and inter-relations of two different GIT compartments,rumen and feces,of 26 Nelore(Bos indicus)bulls,using Next Generation Sequencing(NGS)metabarcoding of bacteria,archaea and ciliate protozoa.Results:We identified 4265 Amplicon Sequence Variants(ASVs)from bacteria,571 from archaea,and 107 from protozoa,of which 143(96 bacteria and 47 archaea)were found common between both microbiomes.The most prominent bacterial phyla identified were Bacteroidetes(41.48%)and Firmicutes(56.86%)in the ruminal and fecal microbiomes,respectively,with Prevotella and Ruminococcaceae UCG-005 the most relatively abundant genera identified in each microbiome.The most abundant archaeal phylum identified was Euryarchaeota,of which Methanobrevibacter gottschalkii,a methanogen,was the prevalent archaeal species identified in both microbiomes.Protozoa were found exclusively identified in the rumen with Bozasella/Triplumaria being the most frequent genus identified.Co-occurrence among ruminal and fecal ASVs reinforces the relationship of microorganisms within a biological niche.Furthermore,the co-occurrence of shared archaeal ASVs between microbiomes indicates a dependency of the predominant fecal metha展开更多
The point of zero salt effect （PZSE） is the soil pH value at which the magnitude of the variable surface charges is not changed due to variations in the ionic concentration of the soil solution. This property influe...The point of zero salt effect （PZSE） is the soil pH value at which the magnitude of the variable surface charges is not changed due to variations in the ionic concentration of the soil solution. This property influences not only electrochemical phenomena occurring at the solid-solution interface but also the flocculation degree of the soil particles. In this study we investigated the relationships between the clay mineralogy and the PZSE values of representative soils of the Sāo Paulo State, Brazil. The results confirmed the usefulness of the difference between the soil pH values measured in 1 mol L^-1 KCl （pHKCl） and in water （pHH2O） （2 pHKCl-pHH2O） for estimating the PZSE of tropical soils, except for the ones rich in exchangeable Al; furthermore, the ApH index （pHKC1 - pHH2O） was highly correlated with the difference between the PZSE and pHH2O values, reiterating the △pH utility for estimating both the signal and the magnitude of the net surface charge of tropical soils. Finally, correlation and multiple regression analyses showed that the PZSE value of weathered non-allophanic tropical soils tends to increase and to equal the soil pH due to the weathering-induced kaolinite destabilization and concomitant Fe- and Al-oxide accumulation.展开更多
文摘It is well-documented that phytochromes can control plant growth and development from germination to flowering. Additionally, these photoreceptors have been shown to modulate both biotic and abiotic stress. This has led to a series of studies exploring the molecular and biochemical basis by which phytochromes modulate stresses, such as salinity, drought, high light or herbivory. Evidence for a role of phytrochromes in plant stress tolerance is explored and reviewed.
基金Petrobras,Center for Tropical Forest Science,The State of São Paulo Research Foundation,Fondation pour la Recherche sur la Biodiversité,Centre National de la Recherche Scientifique,French Investissements d’Avenir funds managed by Agence Nationale pour la Recherche(CEBA,ANR-10-LABX-0025,and TULIP,ANR-10-LABX-0041).
文摘Aims The coastal Brazilian rainforest on white-sand(restinga)ranks among the most fragmented forest types in the tropics,owing to both the patchy distribution of sandy soils and widespread coastal development activities.Here we study the environmental and evolutionary determinants of a forest tree assemblage at a single restinga forest in Southeastern Brazil.We also explore the ability of competing hypotheses to explain the maintenance of species diversity in this forest type,which includes contrasting extremes of edaphic conditions associated with flooding stress.Methods The study was conducted in a white-sand forest permanent plot of 10.24 ha on the coastal plain of Southeastern Brazil.This plot was divided into 256 quadrats of 20×20 m,which were classified into two main edaphic habitats(flooded and drained).Trees with a diameter≥1 cm at breast height were identified.We assembled DNA sequence data for each of the 116 morphospecies recognized using two chloroplast markers(rbcL and matK).A phylogenetic tree was obtained using the maximum likelihood method,and a phylogenetic distance matrix was produced from an ultrametric tree.We analyzed similarity in floristic composition and structure between habitats and related them to cross-plot distances using permutation procedures.Null model torus shift simulations were performed to obtain a statistical significance level for habitat association for each species.The phylogenetic structure for the two habitats and for each 20×20 m quadrat was calculated using the mean phylogenetic distance weighted by species abundance and checked for significance using the standardized effect size generated by 5000 randomizations of phylogenetic tip labels.Important Findings Our results indicate that partitioning among edaphic habitats is important for explaining species distributions and coexistence in restinga forests.Species distributions within the plot were found to be non-random:there was greater floristic similarity within than between habitats,and>40%of the more abundant spec
文摘Glycine max is a photoperiodic short-day plant and the practical consequence of the response is latitude and sowing period limitations to commercial crops. Genetic and physiological studies using the model plants Arabidopsis thaliana and rice （Oryza sativa） have uncovered several genes and genetic pathways controlling the process, however information about the corresponding pathways in legumes is scarce. Data mining prediction methodologies, including multiple sequence alignment, phylogeneUc analysis, bioinformaUcs expression and sequence motif pattern identification, were used to identify soybean genes involved in day length perception and photoperiodic flowering induction. We have investigated approximately 330 000 sequences from open-access databases and have identified all bona fide central oscillator genes and circadian photoreceptors from A. thaliana in soybean sequence databases. We propose a working model for the photoperiodic control of flowering time in G. max, based on the identified key components. These results demonstrate the power of comparative genomics between model systems and crop species to elucidate the several aspects of plant physiology and metabolism.
基金FAPESP(2012/14731–4)to MFSFCAPES PEC-PG 15068–12-9 to AMGD+2 种基金CNPq 142,387–2015-0 to MSCNPq 481,199/2012–8FAPESP-2011/03226–4 to MB
文摘Background： This study evaluated the impact of hormonal modulation at the onset of proestrus on ovarian response and uterine gene expression of beef cows.Methods： A total of 172 anestrous beef cows were assigned to one of four groups according to the treatment with estradiol cypionate（ECP） and/or equine chorionic gonadotropin（eCG） [CON（n = 43）, ECP（n = 43）, eCG（n = 44）and ECP ＋ eCG（n = 42）].Results： ECP-treated cows（ECP and ECP ＋ eCG groups） presented greater occurrence of estrus（44.6% vs. 65.4%; P = 0.01） and pregnancy per AI [47.1% vs. 33.3%; P = 0.07], but similar progesterone（P4） concentration at subsequent diestrus than cows not treated with ECP（CON and eCG groups）. Nonetheless, eCG-treated cows（eCG and ECP ＋ eCG groups） presented larger follicle at timed AI（12.6 ± 0.3 vs. 13.5 ± 0.3 mm; P = 0.03）, greater ovulation rate（96.5%vs. 82.6%; P = 0.008） and greater P4 concentration at d 6（3.9 ± 0.2 vs. 4.8 ± 0.2 ng/mL; P = 0.001） than cows not treated with eCG（CON and ECP groups）. Next, cows with a new corpus luteum 6 d after TAI were submitted to uterine biopsy procedure. Uterine fragments [CON（n = 6）, ECP（n = 6）] were analyzed by RNA-Seq and a total of 135 transcripts were differentially expressed between groups（73 genes up-regulated by ECP treatment）. Subsequently,uterine samples were analyzed by q PCR（genes associated with cell proliferation）. ECP treatment induced greater abundance of PTCH2（P = 0.07） and COL4 A1（P = 0.02）, whereas suppressed EGFR（P = 0.09） expression. Conversely, eCG treatment increased abundance of HB-EGF（P = 0.06）, ESR2（P = 0.09）, and ITGB3（P = 0.05）, whereas it reduced transcription of ESR1（P = 0.05）. Collectively, supplementation with ECP or eCG at the onset of proestrous of anestrous beef cows influenced ovarian responses, global and specific endometrial gene expression.Conclusion： Proestrus estradiol regulate the endometrial transcriptome, particularly stimulating pr
文摘Separately, it is well-documented that phytochromes (phys), gibberellin (GA) and abscisic acid (ABA) strongly control the seed germination in tomato. However, we hipothesized that phys interact with GA or ABA during this response. Thus, we make an analysis of seed germination of ABA deficient (sit), GA constitutive response (pro), phytochrome deficient (au) mutants as well as, specially, au sit and au pro double mutants of tomato?incubated in the dark or light conditions during 120 h [12 h intervals (i)]. Compared to au, which severely?reduced percentage germination (Gi%) and pro, which did not alter Gi%, au pro showed in the light enhanced Gi% and germination speed index (GSI) besides the reduced average germination time (AGT). Moreover, in the dark, germination of au pro was similar to pro. These results indicate that the mechanisms by which GA modulate germination in tomato are light dependent through the phy signaling, whereas intermediary values of Gi%, GSI and AGT in dark and light of au sit compared to au and sit single mutants indicate an additive effect of the au and sit mutations, suggesting that ABA and phy may act through the parallel signaling pathway.
文摘Each year, ethanol production is increasing in Brazil, consequently, the generation of byproducts as well. Among these, the vinasse stands out. With polluting power a hundred times greater than domestic sewage and high concentration of minerals, vinasse is generated in large volumes. Because of these characteristics, it is widely used in fertirrigation. However, it is composed of about 97% water, inflating the cost of the transport from the plant to the field. For these reasons, removing water from the vinasse and the consequent concentration of solids is an alternative management and application of this by-product. This project aimed to analyze the efficiency of various physical and chemical processes in the removal of water from the vinasse.
基金supported by grants from FAPESP,CNEN and CNPq,Brazilian funding agencies for the promotion of science.
文摘A model based on Watson’s power law for the species-area relationship predicts that full global warming, projected up to the year 2050, could provoke the disappearance of roughly one-quarter of existing species. Here, an alternative approach is worked out, based on the combination of two ecology laws: Taylor and Watson’s power laws, where the former relates species variability with their mean abundance. Just how severely global warming would affect not only the number but the diversity of the surviving species is addressed by this approach, while at the same time giving indications for the post-disaster fate of the remaining species (extinction or recovery).
文摘The growth of a tree or a forest settlement is of great value to a forest enterprise, because many decisions are directly dependent of this information, for instance, determining the optimal cutting age. This study aims to apply a new class of models to fit growth curves for diameter and height of Eucalyptus grandis X Eucalyptus urophylla seedling data. Data were collected from a trial conducted in a green house at the Natural Resources Department at School of Agriculture, Botucatu, S?o Paulo, Brazil. The experiment’s design was completely randomized with eight treatments and four replications. In this trial, the growth variables referring to the height and the diameter were evaluated, being measured five and four times, respectively. The methodology was carried in a mixed longitudinal model using a new approach based on Box-Cox Normal (BCN) distribution, and comparisons with this model were made assuming normality of the data. The results revealed that the BCN mixed model provided similar results to the standard model in order to estimate growth curves;however, the BCN model was the best result according to Akaike criterion, considering the slight asymmetry in the data set. This approach is of great interest in case of outliers and robust procedures for parameter estimation.
基金supported by the State of Esprito Santo Research Foundation(FAPES,Grant No.65768051/14)。
文摘Drought is considered the main environmental factor limiting productivity in eucalyptus plantations in Brazil. However, recent studies have reported that exposure to water deficit conditions enables plants to respond to subsequent stresses. Thus, this study investigates the ecophysiological acclimatization of eucalyptus clones submitted to recurrent water deficit cycles. Eucalyptus seedlings were submitted to three recurrent water deficit cycles and anatomical, morphological and physiological changes were analyzed. The results were:(1) Eucalyptus seedlings responded to water deficits by directing carbohydrates to root and stem growth;(2) Size and number of stomata were reduced;(3) Stomatal conductance decreased which allowed the plants to reduce water losses through transpiration,increasing instantaneous water use efficiency;(4) The relationship between gas exchanges and available water contents allowed the seedlings to uptake the retained soil water athigher tensions;and,(5) Physiological recovery from subsequent water deficits became faster. As a result of these changes, the eucalyptus seedlings recovered from the same degree of water stress more rapidly.
文摘The number workable days (NWD) for agricultural field operations is of great importance for sizing agricultural machinery fleets. This is especially pivotal for sugarcane harvest, which extends from 8 to 10 months/year. In light of this, the current study aimed at defining criteria for obtaining the NWD for rational sugarcane harvest at different sites in the state of São Paulo, southern Brazil, taking into account both a general and a specific criteria. For this purpose, data from harvest interruption of 30 sugar mills in southern Brazil throughout periods ranging from two to five years were used. The following variables were tested as criteria for defining harvest interruption: minimum precipitation (PREC);soil water holding capacity (SWHC);and the limit of the ratio between actual soil moisture (SM) and SWHC. Based on such a specific criterion ascribed to each site along with a general criterion, NWD maps were prepared for the state of São Paulo, Brazil. The results showed that there were variations from the definition criteria of NWD at the different sites in the state. However, the use of a general criterion for harvest interruption, based on PREC ≥ 3 mm, SWHC = 40 mm and SM/SWHC ≥ 90%, provided accurate results. During the validation of these criteria, the NWD maps generated from the individual criterion proposed for each site resulted in an average error of 24.9 days/year, whereas the map generated from the general criterion culminated in an average error of 4.4 days/year.
基金financially by FAPESP (So Paulo Research Foundation,Brazil)CAPES (Coordination for the Improvement of Higher Level Personnel,Brazil)
文摘Eucalyptus benthamii is a forest species of economic interest that has difficulty with seed production and also is considered to have difficulty with adventitious rooting using propagation techniques, such as cutting or mini-cutting. We aimed to assess the adventitious rooting percentage under different storage times in low temperatures and at various IBA （indole-3-butyric acid） concentrations to determine the optimal time of permanence for rooting Eucalyptus benthamii minicuttings in a greenhouse. Shoots collected from mini-stumps cultivated in a semi-hydroponic system were used to obtain the mini-cuttings. For the first experiment, the mini-cuttings were stored at 4℃ for 0 （immediate planting）, 24, 48, 72, 96 and 120 h. The second experiment evaluated the rooting dynamic to determine the optimal time of permanence for minicuttings in a greenhouse. The basal region of the mini-cutting was treated with various IBA solutions： 0 （free of IBA）, 1,000, 2,000, 3,000 and 4,000 mg.L^-1. Every seven days （0 （immediate planting）, 7, 14, 21 and 28 days）, destructive sampling of the mini-cuttings was performed to evaluate the histology of the adventitious rooting. Eucalyptus benthamii minicuttings should be rooted immediately after the collection of the shoots. The 2,000 mg.L^-1 IBA concentration induced a greater speed and percentage of adventitious rooting, and an interval of 35 to 42 days was indicated for permanence of the mini-cuttings in the greenhouse. Expo- sure to low temperature induced adventitious root formation with diffuse vascular connections.
基金supported by FAPESP (So Paulo Research Foundation, Brazil)CAPES (Coordination for the Improvement of Higher Level, Brazil)
文摘Nodal segments from secondary branches of saplings of Phyllostachys bambusoides were inoculated in MS medium to assess the in vitro morphogenic response of leaf sheath through the induction to callogenesis by Picloram（4-amino-3,5,6-trichloropicolinic acid） at different concentrations of carbohydrate under the same conditions with presence or absence of luminosity.In our experiment,secondary explants were kept in MS medium containing 8.0 mg·L-1 of Picloram for the callus formation.Calluses were transferred in MS medium supplemented with sucrose,fructose and glucose（control,2%,4% and 6%）.Results show that Picloram induced the callogenesis in leaf sheath.The secondary embryogenesis was formed in yellow-globular callus.The sucrose as carbohydrate source in the absence of light was more efficient to induce rhizogenesis.Glucose was more efficiency in the presence of light.Callogenic induction and further embryogenesis evidenced the competence and determination of leaf sheath cells.
基金supported by National Funds of FCT-Portuguese Foundation for Science and Technology(Grant No.UIDB/04033/2020)supported by National Funds of FCT-Portuguese Foundation for Science and Technology(Grants No.UIDB/00616/2020 and UIDP/00616/2020)Adriana Monteiro da Costa was granted a scholarship“Seleção de indicadores para avaliação da qualidade do solo emáreas de pastagem degradada”,financed by the Public Ministry of Minas Gerais through the Funepu-Fundação de Ensino e Pesquisa de Uberaba.
文摘Different global agendas have discussed the role of soils in mitigating and reducing global problems related to climate change,food security,biodiversity and erosion,among others.With this in mind,the aim was to draw up an overview of the main soil agendas in Europe and Brazil,analysing their impact on the establishment of legal frameworks for soil use and conservation.In Brazil,pastures are seen as an important alternative for converting degraded areas into ecosystem services.To this end,a literature review was carried out using databases on the Scopus,Web of Science,Science Direct and Scielo platforms,as well as consulting documents from the European Union Missions in Horizon Europe and Brazilian legislation on the subject.In a pilot river basin,the Potential for Conservation Use(PCU)method was applied,which is used in Brazil to assess the impacts of different uses on the natural capital of soils,serving as a metric to guide public soil conservation policies.It was concluded that,on the European scene,discussions on soils have taken place in an integrated and organised way,with actions to mobilise different players in society.In Brazil,even though there are important legal frameworks,actions are still restricted and disjointed,pointing to the need for progress in soil governance.In both scenarios,there is a need for scientifically validated metrics at regional scales that can contribute to a harmonised database capable of subsidising the development of efficient public policies to advance soil conservation at a global level.
文摘The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with high nutrient content. The purpose of this study was to assess the effects of foliar applications of calcium and molybdenum on yield and seed physiological potential in common bean plants. A randomized block design was implemented, with the treatments fixed in a factorial scheme: two molybdenum rates (with or without) and four calcium rates, with four replications. The calcium rates applied on the leaves were 0, 150, 300 and 600 g·ha-1 for the first year of the investigation (2005) and 0, 300, 600 and 900 g·ha-1 for the second year (2006). In both years, the molybdenum rates applied on the leaves were 0 g·ha-1 (without) and 75 g·ha-1 (with). The results showed that the foliar calcium application, with or without molybdenum, did not improve yield. Foliar application of calcium alone improved seed physiological potential in common bean plants when applied at the full bloom stage.
文摘During the industrial fermentation process in the production of fuel ethanol, yeasts are subject to several stressing conditions. The survival and the permanence of strains introduced in the process correlate with the capability of these yeasts in resisting to physical and chemical stresses, as well as their recovering ability to compete with contaminating micro-organisms commonly present in this industrial process. We aim at the selection of Saccharomyces cere visiae strains having this capability and ability. In this sense, cultivations of strains with industrial interest were irradiated with gammas ray at a wide dose interval. Growing curves for the strains were analyzed by means of their relative growth, a new concept here introduced, which allows a better understanding of the growing and recovering processes following radiative stress. It was found that gamma radiation could be used as an alternative method to quantify growing capabilities of S. cerevisiae strains under stressing conditions. It was also shown that this radiological method could be utilized as an additional procedure to select best robust industrial strains. This radiological method simplifies traditional analysis of strain viability, by avoiding the great number of necessary and consecutive fermentation assays.
文摘The Brazilian citrus chain is comprised by an upstream farm sector, made up of numerous heterogeneous （by size and technology） farm units serviced by input suppliers, and a downstream segment consisting of a small number of processing industries. Our study examines the behavior of citrus pricing along this supply chain, focusing on the relationship between orange juice prices established in international markets and orange fruit prices paid to Brazilian farmers. Results indicate that the price of orange fruit is fundamentally linked to the price of its juice, regardless of data source considered for testing. Evidence was found indicating that there is asymmetry of price transmission within the Brazilian orange sector, with juice price increases being transmitted to the farmer in smaller proportions than juice price decreases. The results of our study did not give a particularly strong indication of the cause of this price asymmetry.
文摘Considering that the pyroligneous liquor obtained from pyrolysis of various types of biomass has antiviral activity, the main objective of the present study was to evaluate the antimicrobial action of the methanolic fraction extracted from bamboo （Dendrocalamus asper） pyroligneous liquor in relation to Escherichia coli and Staphylococcus aureus bacteria. The pyroligneous liquor was recovered by laboratorial bamboo pyrolysis at 350 °C and then fractioned by liquid-liquid separation with methanol and hexane. After solvent evaporation, we collected the methanolic extract, which was later diluted in methanol and used in the diffusion disc assay of E. coli and S. aureus at concentrations of 0.125, 0.500, 0.750 and 1.000 mg. Through GC/MS analysis, it was possible to qualitatively identify 92 chemical compounds in the methanolic fraction. Treatment with the methanolic fraction inhibited cellular growth and caused a variety of morphological variations in size as well as deformities in the bacterial cell walls, establishing an antimicrobial activity profile. This finding supports the National Policy for Incentives for Sustainable Management and Cultivation of Bamboo （PNMCB） and has benefits to the society and environment as a whole, as it demonstrates the possibility of adding value to a byproduct of pyrolysis.
基金funded by the Sao Paulo Research Foundation(FAPESP)through a doctorate scholarship(Grant no.2013/10922-2)Research Internship Abroad(Grant no.2014/14213-9)
文摘Background: With the objective of increasing knowledge on biomass and carbon stocks, and thus improving the accuracy of published estimates, the present study explored wood density and carbon concentration of coarse woody debris (diameter≥10) by decay class in a Seasonal Semi-deciduous Forest (SSF) area in the Atlantic Rain Forest and in a Cerrado sensu-stricto (CSS) area (Brazilian savanna), in Brazil. Two strata were identified in each area and ten sampling units were systematic located in each stratum. Data were collected according to the line intersect sampling method. Each tallied element, the diameter, length, and perpendicular width were recorded at the transect intersection point. Each element was classified into a decay class, and the species was identified when possible. Sample discs were cut from each element, from which cylindrical samples were extracted and oven-dried to determine density. These cylinders were milled and analyzed using a LECO-C632 to determine carbon concentration as percentage of mass. Results: In both areas, wood density decreased as the decay class increased. For SSF the mean carbon concentration of all analyzed samples was 49.8% with a standard deviation of 3.3, with a range of 27.9–57.0% across 506 observations. For CSS the general mean was 49.6% with a standard deviation of 2.6, with a range of 31.2–54.5% over 182 observations. Carbon concentration barely change between decay classes. Carbon stock was estimated at 3.3 and 0.7 MgC/ha for the SSF and the CSS, respectively. Similar results were obtained when using a 50% conversion constant. Conclusions: The present study concludes that wood density decreases as the woody debris becomes more decomposed, a pattern found in many previous studies. The carbon concentration, however, barely changes between decay classes, and that result is consistent with most of the literature reviewed. Our carbon concentrations are very close to the 50% used most commonly as a conversion factor. We strongly recommend that future studies of CWD e
基金This study was conducted with funding from EMBRAPA,São Paulo Research Foundation scholarship to BGNA(grant number:2017/12642–8)the National Council for Scientific and Technological Development(CNPq,grant number:428153/2018)and fellowships to LCAR and LLC.
文摘Background:The success of different species of ruminants in the colonization of a diverse range of environments is due to their ability to digest and absorb nutrients from cellulose,a complex polysaccharide found in leaves and grass.Ruminants rely on a complex and diverse microbial community,or microbiota,in a unique compartment known as the rumen to break down this polysaccharide.Changes in microbial populations of the rumen can affect the host’s development,health,and productivity.However,accessing the rumen is stressful for the animal.Therefore,the development and use of alternative sampling methods are needed if this technique is to be routinely used in cattle breeding.To this end,we tested if the fecal microbiome could be used as a proxy for the rumen microbiome due to its accessibility.We investigated the taxonomic composition,diversity and inter-relations of two different GIT compartments,rumen and feces,of 26 Nelore(Bos indicus)bulls,using Next Generation Sequencing(NGS)metabarcoding of bacteria,archaea and ciliate protozoa.Results:We identified 4265 Amplicon Sequence Variants(ASVs)from bacteria,571 from archaea,and 107 from protozoa,of which 143(96 bacteria and 47 archaea)were found common between both microbiomes.The most prominent bacterial phyla identified were Bacteroidetes(41.48%)and Firmicutes(56.86%)in the ruminal and fecal microbiomes,respectively,with Prevotella and Ruminococcaceae UCG-005 the most relatively abundant genera identified in each microbiome.The most abundant archaeal phylum identified was Euryarchaeota,of which Methanobrevibacter gottschalkii,a methanogen,was the prevalent archaeal species identified in both microbiomes.Protozoa were found exclusively identified in the rumen with Bozasella/Triplumaria being the most frequent genus identified.Co-occurrence among ruminal and fecal ASVs reinforces the relationship of microorganisms within a biological niche.Furthermore,the co-occurrence of shared archaeal ASVs between microbiomes indicates a dependency of the predominant fecal metha
基金the State of So Paulo Research Foundation-FAPESP, Brazil (No. 98/01502-8).
文摘The point of zero salt effect （PZSE） is the soil pH value at which the magnitude of the variable surface charges is not changed due to variations in the ionic concentration of the soil solution. This property influences not only electrochemical phenomena occurring at the solid-solution interface but also the flocculation degree of the soil particles. In this study we investigated the relationships between the clay mineralogy and the PZSE values of representative soils of the Sāo Paulo State, Brazil. The results confirmed the usefulness of the difference between the soil pH values measured in 1 mol L^-1 KCl （pHKCl） and in water （pHH2O） （2 pHKCl-pHH2O） for estimating the PZSE of tropical soils, except for the ones rich in exchangeable Al; furthermore, the ApH index （pHKC1 - pHH2O） was highly correlated with the difference between the PZSE and pHH2O values, reiterating the △pH utility for estimating both the signal and the magnitude of the net surface charge of tropical soils. Finally, correlation and multiple regression analyses showed that the PZSE value of weathered non-allophanic tropical soils tends to increase and to equal the soil pH due to the weathering-induced kaolinite destabilization and concomitant Fe- and Al-oxide accumulation.
