Showing papers in "Acta Scientiarum. Biological Sciences in 2015"
TL;DR: The presence and accumulation of cadmium in the soil cultivated with T. aestivum may trigger liabilities in productivity and/or viability caused by its toxicity as from 0.03mM concentrations absorbed by the plant roots.
Abstract: Cadmium toxicity in seed germination and seedling growth of wheat ( Triticum aestivum , var. IAC-370) is assessed. The ecotoxicological effects of six experimental concentrations of cadmium (0.03; 0.06; 0.12; 0.6; 1.2; 2.4; 4.8 mM), and control were evaluated. All assays were performed in quadruplicates with 25 seeds per replication in Petri dishes. Responses for toxic effect comprised the variables germination percentage, index of velocity of germination (IVG), length of aerial section and root of the seedlings, green and dry mass of the seedlings. Results showed that T. aestivum seeds exposed to cadmium decreased their normal germination percentage as from 0.03 mM concentration, with a 31% reduction of germination percentage and a 20% decrease in IVG. Cadmium´s inhibition effect on initial growth of seedlings influenced growth of roots and aerial part as from concentration 0.12 mM and reduced the production of green and dry mass of seedlings as from 0.06 mM. The presence and accumulation of cadmium in the soil cultivated with T. aestivum may trigger liabilities in productivity and/or viability caused by its toxicity as from 0.03mM concentrations absorbed by the plant roots.
18 citations
TL;DR: The fish collection of the Universidade Federal de Rondonia, recently established, contains about 41% of freshwater fish species known to occur in Brazil, and 24% of South America as mentioned in this paper.
Abstract: Biological collections preserve the biodiversity of a nation. The fish collection of the Universidade Federal de Rondonia, recently established, contains about 41% of freshwater fish species known to occur in Brazil, and 24% of South America. The biological material is distributed into 1,067 species, 21,963 lots and 149,192 specimens, gathered during five years of work. From this collection, 99% of the lots have georeferenced location, and 94% of the species were sampled in the Madeira River basin, the largest tributary in flow, drainage area and sediment discharge of the Amazonas River basin. Among the 1,008 species collected in the Madeira River basin, 80% were reviewed by Brazilian, North American and French experts, and represents the highest richness among tributaries of the Amazonas River and other rivers worldwide. Fish collection from the Madeira River basin deposited in the ichthyological collection of the Universidade Federal de Rondonia accounts for about 75% of the lots and specimens of fish from that basin available for study in collections worldwide.
17 citations
TL;DR: An efficient in vitro propagation method was established for Brasilidium forbesii (Hook.) Campacci using transverse and longitudinal thin cell layer (tTCL and lTCL) culture systems using vermiculite as the substrate (100% survival).
Abstract: An efficient in vitro propagation method was established for Brasilidium forbesii (Hook.) Campacci using transverse and longitudinal thin cell layer (tTCL and lTCL, respectively) culture systems. Six-month-old protocorms from in vitro germinated seeds were used for this study. TCLs (1.0-mm thick) from protocorms were grown on Woody Plant Medium (WPM) supplemented with benzyladenine (BA) (0.5–4.0 µM).The lTCL technique was more efficient for inducing protocorm-like bodies (PLBs) and regenerating shoots than the tTCL technique. The frequency of PLB formation was influenced by BA concentration, and the lTCL explant grown on a medium containing 2.0 µM BA produced the highest percentage of new protocorms (77%) with a total of 22.7 PLBs per explant, after the first subculture on the same medium. Plantlet development was optimal on WPM medium containing 3.0 g L -1 activated charcoal, and indole-3-butyric acid was not necessary for rooting. Regenerated plants were successfully acclimatized in a greenhouse after 16 weeks using vermiculite as the substrate (100% survival).
15 citations
TL;DR: The area was considered a recruitment and reproduction area with the highest reproductive activity between December 2011 and July 2012 and the constant frequency of mature I. parvipinnis and S. microps in catches throughout the year suggests that these species are multiple spawners and use the area during their reproductive period.
Abstract: The Brazilian prawn fishery, as other bottom trawling fisheries, is considered quite efficient in catching the target species but with low selectivity and high rates of bycatch. The family Sciaenidae prevails among fish species caught. The study was conducted in the Pernambuco State (Barra de Sirihaem), northeastern Brazil. From August 2011 to July 2012, 3,278 sciaenid specimens were caught, distributed into 16 species, 34.2% males and 41.5% females. Larimus breviceps, Isopisthus parvipinnis, Paralonchurus brasiliensis and Stellifer microps were the most abundant species. The area was considered a recruitment and reproduction area with the highest reproductive activity between December 2011 and July 2012. The constant frequency of mature I. parvipinnis and S. microps in catches throughout the year suggests that these species are multiple spawners and use the area during their reproductive period. Since most individuals caught as bycatch have not reached sexual maturity, evidencing the need for a better monitoring of the area and the Sciaenidae caught as bycatch, once this incidental caught can cause fluctuations in the recruitment, increasing the proportion of immature individuals in the population and negatively affecting the reproductive success of the species.
15 citations
TL;DR: The data from this study are indicative of the antibacterial activity of L. camara ’s extracts and its potential in modifying the resistance of aminoglycosides analyzed.
Abstract: Several plants have been evaluated not only for alone antimicrobial activity, but as resistance-modifying agent. This work is the first on the modulation of antibiotic activity by Lantana camara L. extracts against multiresistant strains of Escherichia coli and Staphylococcus aureus . The antibacterial activities of leaf and root ethanol extracts alone or in association with aminoglycosides were determined against bacterial strains by a microdilution test. The minimum inhibitory concentration (MIC) of the extracts was compared with of the aminoglycosides. Phytochemical prospection revealed the presence of quinones, steroids, flavonoids, saponins, tannins, triterpenoids and alkaloids. The results showed antibacterial activities of the extracts and synergistic effects combined with aminoglycosides. The most expressive effects were obtained with root extract but gentamicin or but neomycin against E. coli with MICs decreased (312 to 5 µg mL -1 ). The data from this study are indicative of the antibacterial activity of L. camara ’s extracts and its potential in modifying the resistance of aminoglycosides analyzed.
13 citations
TL;DR: A protocol for the in vitro germination and callus induction in Pyrostegia venusta, a medicinal plant species from the Brazilian savannah, is provided and all treatments resulted in obtaining calli with contents of total phenolic compounds and flavonoids at or above the initial explant.
Abstract: A protocol for the in vitro germination and callus induction in Pyrostegia venusta, a medicinal plant species from the Brazilian savannah (Cerrado) is provided. The establishment of cultures of P. venusta was originally obtained from seeds germinated in vitro and induced callus directly from leaf explants of seedlings. Seeds were germinated on MS and WPM media containing 100 and 50% of salt concentration, supplemented with 30 g L -1 sucrose. Callus induction consisted of the inoculation of leaf segments on MS medium plus 2,4-D or BAP in the presence or absence of light. The germination percentage averaged 85% and the aerial parts and roots of seedlings obtained in WPM with 50 and 100% of salt concentration showed elevated contents of total phenolic compounds and flavonoids compared to those obtained on MS medium. Calli induced with lower concentrations of 2,4-D had higher fresh and dry weight values. All treatments resulted in obtaining calli with contents of total phenolic compounds and flavonoids at or above the initial explant, highlighting treatments containing 9.05 μM 2,4-D and 8.88 μM BAP in the presence and absence of light, and 17.75 μM BAP in the absence of light.
13 citations
TL;DR: Current assay showed the feasibility of statistical tools to optimize the physical and nutritional parameters for the production of hyaluronic acid and the improvement of the fermentation process.
Abstract: The production of hyaluronic acid by Streptococcus zooepidemicus ATCC 39920 with varying rates of pH (6.0, 7.0, 8.0), temperature (34; 37; 40°C), agitation (100, 150, 200 rpm), glucose (10, 20, 30 g L -1 ) and yeast extract concentration (10, 20, 30 g L -1 ) was evaluated by statistical approaches. The best conditions for the production of hyaluronic acid was pH 8.0, 37°C and 100 rpm in a medium containing 30 g L -1 glucose and yeast extract, for a production of 0.787 g L -1 . Temperature, pH and yeast extract were significant variables (p < 0.05). Yeast extract and pH had a positive effect on the production of the polymer. Lactate, formate and acetate synthesis were also analyzed. Current assay showed the feasibility of statistical tools to optimize the physical and nutritional parameters for the production of hyaluronic acid and the improvement of the fermentation process.
12 citations
TL;DR: Quadrat sampling method was slightly more efficient to analyze the species richness and much more effective to assess the abundance than the use of only direct search qualitative method, mainly considering tiny and/or cryptobiotic invertebrates.
Abstract: Quadrat sampling is a method used for a long time in plant ecology studies but only recently it has been used with focus on fauna. For the cave fauna samplings, there are rare works applying this methodology. The present study compared the methods of quadrat sampling with direct search qualitative for terrestrial cave fauna. For this, we conducted five sampling collections in a limestone cave in central Brazil. Quadrat sampling contributed with 121 exclusive species and 716 specimens and direct search qualitative method contributed with 91 exclusive species and 355 specimens. Mann-Whitney test evidenced significant differences between the two methods. We demonstrated that quadrat sampling method was slightly more efficient to analyze the species richness and much more effective to assess the abundance than the use of only direct search qualitative method, mainly considering tiny and/or cryptobiotic invertebrates (e.g., earth worms, symphylans, psocopterans, trichopterans, dipterans, small spiders, and small isopods). We recommend the association of different methods to test patterns in cave fauna, since incomplete sampling may lead to erroneous estimates and equivocated decisions about management, impact studies and cave conservation.
12 citations
TL;DR: In this paper, the authors investigated monthly variations of social wasps in microhabitats within a forest-agriculture mosaic in the Brazilian State of Rio Grande do Sul.
Abstract: Wasps, important agents for the control of insect population, have been scantily studied in the Brazilian State of Rio Grande do Sul. Current study investigates monthly variations of social wasps in microhabitats within a forest-agriculture mosaic. Samples were collected between February 2013 and February 2014, through active search and baited traps made from 2 L transparent PET bottles, in five microhabitats, namely, forest, monoculture, polyculture and the edges between the forest fragment and monoculture and polyculture, in the municipality of Doutor Mauricio Cardoso. Statistical tests, similarity indices, dominance and constancy as well as PCoA were used for data analysis to group the collection. A total of 953 specimens were collected, distributed across 15 species and seven genera. Abundance differed between microhabitats and the monoculture cultivation was least similar to the other microhabitats. PCoA identified three different groups. Abundance was positively correlated with temperature, negatively correlated with air humidity and was not correlated with wind velocity. Social wasps are able to utilize resources outside the forest fragments, but monocultures may create barriers for their dispersal.
11 citations
TL;DR: In this paper, the authors evaluated the phytosociology and floristic composition of tree species in the eastern Amazon, at the Iratapuru River Sustainable Development Reserve (RDS), State of Amapa.
Abstract: This study aims to evaluate the phytosociology and floristic composition of tree species in the eastern Amazon, at the Iratapuru River Sustainable Development Reserve (RDS), State of Amapa. Fouteen quarters with dimensions of 100 m x 100 m were randomly inventoried, and 50 sub-plots of 10 m x 20 m were established. In each sub-plot all living individuals were sampled, being taken from the height data and DAP (breast height diameter) for tree species ≥ 10 cm. A total of 5,233 individuals belonging to 33 families and 184 species were registered. The families with the largest number of species were Fabaceae (32), Lauraceae (17), Sapotaceae (12), Moraceae (10), Lecythidaceae (8) and Annonaceae (8). The six most abundant families (18.18% of total families) in the present study were responsible for more than half (57.92%) of the total number of species. The floristic structure of the area studied was diverse, with species of varied interests, including: medicinal, timber and oil-producing.
9 citations
TL;DR: A greater dissimilarity between the rotifer communities according to increasing distance from the Porto Primavera Dam is suggested and a higher influence of the environmental variables related to trophic conditions was observed in the last sampling site, and influenced indirectly the occurrence and abundance of some rotifer species, due to increased availability of food resources, confirming the predicted hypothesis.
Abstract: The construction of reservoirs imposes substantial impact on freshwater ecosystems and changes the ecological aspects of the lotic system downstream of dams. We hypothesized an increasing dissimilarity between communities in the sampling sites according to increasing distance from the Porto Primavera Dam. In addition, we expect that the rotifer community in the last sampling site will be influenced more by environmental variables related to trophic status. Samplings were conducted under the water surface of ten sites on the Parana River in August 2013. Environmental variables were also determined. The highest number of taxa belonged to families Brachionidae, Lecanidae and Trichocercidae. The most abundant species was observed to Synchaeta oblonga, Keratella cochlearis, Brachionus calyciflorus. The species dissimilarity between sampling sites, tested using the Sorensen index, showed high dissimilarity between sampling sites. Redundancy analysis indicated a significant relationship between environmental variables (total phosphorus and ammonia) and abundance of Brachionus calyciflorus and Keratella cochlearis, in the last sampling site. Our results suggest a greater dissimilarity between the rotifer communities according to increasing distance from the Porto Primavera Dam. In addition, a higher influence of the environmental variables related to trophic conditions was observed in the last sampling site, and influenced indirectly the occurrence and abundance of some rotifer species, due to increased availability of food resources, confirming the predicted hypothesis.
TL;DR: The nectarivorous bats predominated numerically both in the dry season as in rainy, while frugivores became prominent, in terms of both the number of species and individuals, during the wet season.
Abstract: The caatinga scrublands are relatively poorly-studied, and few data are available on the biome’s chiropteran fauna. The present study focuses on the bat community of the arboreal caatinga of Serra da Guia. Bats were trapped in mist-nets on three new moon nights per month between October, 2008, and September, 2009. Atotal of 157 individuals were captured, representing 12 species. Species richness estimated by Jackknife1 was 14.8. Glossophaga soricina and Carollia perspicillata were by far the most common species, accounting for 56.7% of the specimens captured. Species diversity was 1.80, while equitability was 0.72. There was no significant seasonal difference in species diversity or evenness. However, the present study recorded a clear seasonal shift in community structure. The principal difference in species composition was related to the temporal distribution of the rarest forms – all of the seven rarest species were recorded exclusively in only one season (dry or wet). The nectarivorous bats predominated numerically both in the dry season as in rainy, while frugivores became prominent, in terms of both the number of species and individuals, during the wet season. The predominance of stenodermatine bats during the wet season almost certainly reflects the increased availability of resources for this group during this part of the year.
TL;DR: A parasitological analysis of 34 specimens of Acestrorhynchus lacustris collected in the Peixe River, Anhembi, Sao Paulo State, Brazil found that 33 of these were infected by at least one species of metazoan parasite.
Abstract: From March to April 2010, specimens of Acestrorhynchus lacustris were collected in the Peixe River, Anhembi, Sao Paulo State, Brazil. This characid, commonly known as peixe-cachorro, has a preference for lentic habitats and it features carnivorous habits, with an important role in the food chain. This study aimed to carry out a parasitological analysis of 34 specimens of A. lacustris, and 33 of these were infected by at least one species of metazoan parasite. Nine species were identified: Ameloblastella sp. and Diaphorocleidus sp. (Monogenea); Ascocotyle sp., Diplostomidae gen. sp. and Sphincterodiplostomum musculosum (Digenea); Contracaecum sp., Philometroides caudata , Procamallanus ( Spirocamallanus ) inopinatus and P. (S.) saofranciscensis (Nematoda). Except P. caudata and P. (S.) saofranciscensis , all parasites showed prevalence higher than 10%. There was a positive correlation between host weight and length and the Ameloblastella sp. Diaphorocleidus sp. was the dominant species. No species was considered central. All parasites showed an aggregated distribution. The parasite community of A. lacustris was characterized by high richness (d = 0.85) and uniformity (J’ = 0.85) and low diversity (HB = 0.56). Except Nematoda, all other parasites were recorded for the first time in this host. Ameloblastella sp., Diaphorocleidus sp. and Ascocotyle sp. are recorded for the first time in the Peixe River.
TL;DR: In this article, the authors compared responses for Carlson's TSI (1977) and its derivations for Brazilian reservoirs from data collected in the Pereira de Miranda Reservoir (State of Ceara, Brazil), and analyzes the influence of local conditions on results and their applicability to reservoirs in the semiarid region.
Abstract: The Carlson’s (1977) Trophic State Index (TSI) is a widely employed tool to estimate the degree of eutrophication in a reservoir. In Brazil, the need of a classification system that would take into account regional characteristics employed adjusted indexes generated by data from reservoirs in the southeastern region of the country. Current research compares responses for Carlson’s TSI (1977) and its derivations for Brazilian reservoirs from data collected in the Pereira de Miranda Reservoir (State of Ceara, Brazil), and analyzes the influence of local conditions on results and their applicability to reservoirs in the semiarid region. TSIs were calculated by data on total phosphorus, chlorophyll a and water transparency. The reservoir was estimated as mesotrophic based on the chlorophyll a variable, and between eutrophic and hyper-eutrophic when based on total phosphorus data and water transparency. Results showed the need to consider intrinsic factors in the discussion on the applicability of TSIs to reservoirs in the semiarid region since the peculiar hydro-climatic conditions and morphometric characteristics make them even more vulnerable to disturbance agents, such as winds which have a significant influence on processes that determine the trophic state.
TL;DR: The results indicate predominance of pollen types belonging to the families Fabaceae and Myrtaceae, which suggests that the bees preferred foraging from trees and shrubs, should be included in regional reforestation projects in order to improve management of this bee species and honey production.
Abstract: Regional-level studies of floral resources used by social bees for honey production can contribute to the improvement of management strategies for bee pastures and colonies, by identifying the most visited flowers and thus characterizing the various geographical origins of honey. The objective of this study was to investigate, through pollen analysis, the types of pollen and nectar sources used by the urucu bee (Melipona scutellaris L.) in the North Coast of Bahia. Honey samples were taken monthly from five colonies in an apiary from August 2010 to July 2011. Pollen analysis of honey was performed by using the acetolysis method, followed by qualitative and quantitative analysis of pollen grains. Fifty pollen types belonging to 40 genera and 17 families were identified. The results indicate predominance of pollen types belonging to the families Fabaceae and Myrtaceae, which suggests that the bees preferred foraging from trees and shrubs. These plants should be included in regional reforestation projects in order to improve management of this bee species and honey production.
TL;DR: The importance of each component in structuring Oligochaeta community was evidenced, nonetheless, in a different way between environments with more similar (nestedness to lentic and turnover to lotic) or dissimilar (almost the same contribution of both) features.
Abstract: We tested the hypothesis that the contribution of the nestedness component is higher in environments with more similar features (lentic or lotic), whereas the contribution of the turnover component is higher in environments with more dissimilar features (lotic vs. lentic). To this end, we partitioned beta diversity of the Oligochaeta community into 12 environments of the Upper Parana River floodplain. We recorded 986 individuals of 17 taxa. Through Redundancy Analysis, we observed a differentiation between lentic and lotic habitats both by environmental features as species composition. Our hypothesis was partially supported, because in environments with more similar hydrological characteristics, we observed a greater contribution of the nestedness component only in lentic environments, whereas in lotic environments, the turnover component showed a higher value. Moreover, when analyzed the different environments (lentic vs. lotic), we noticed a very similar contribution of both components. Some species were more frequent, as A. pigueti and P. americana, while others were exclusive to some environments (N. bonettoi and H. aedeochaeta). We evidenced the importance of each component in structuring Oligochaeta community, nonetheless, in a different way between environments with more similar (nestedness to lentic and turnover to lotic) or dissimilar (almost the same contribution of both) features.
TL;DR: Studies on new microbial sources of cellulas and accurate assessment of the steps that increase cellulase production are essential strategies to reduce the number of harmful bacteria in the environment.
Abstract: Studies on new microbial sources of cellulase and accurate assessment of the steps that increase cellulase production are essential strategies to reduce costs of various processes using such enzymes. This study aimed at the selection of cellulase-producing filamentous fungi, and at the research of parameters involving cellulase production by submerged fermentation. The first test consisted of selecting the best cellulase-producing microorganisms (FPase) in Erlenmeyer flasks containing 200 mL of specific growth medium. The next test was designed to further investigate the enzyme production in fermentation with four types of soluble sugars: glucose, lactose, sucrose and xylose. In bioreactor tests, three different inoculation strategies were analyzed. The best FPase activity was presented by the strain Trichoderma sp. CMIAT 041 (49.9 FPU L -1 ) and CMCase by the fungus Lasiodiplodia theobromae CMIAT 096 (350.0 U L -1 ). Sucrose proved to be the best option among the soluble sugars tested, with higher rates of FPase activity (49.9 FPU L -1 ) and CMCase (119.7 U L -1 ). The best inoculation strategy for the bioreactor was a spore suspension obtained from a semi-solid state fermentation of wheat bran for 72h.
TL;DR: In this paper, the Plackett-Burman design was used to evaluate the effects of 12 independent variables on the production of tannase under solid-state fermentation (SSF) using jamun leaves as substrate.
Abstract: The production of tannase by Aspergillus sp. GM4 under solid-state fermentation (SSF) was investigated using different vegetables leaves such as mango, jamun, coffee and agricultural residues such as coffee husks, rice husks and wheat bran. Among substrates used jamun leaves yielded high tannase production. The Plackett-Burman design was conducted to evaluate the effects of 12 independent variables on the production of tannase under SSF using jamun leaves as substrate. Among these variables, incubation time, potassium nitrate and tannic acid had significant effects on enzyme production. The best incubation time was studied and others variables were optimized using the Central Composite Design. The best conditions for tannase production were: incubation time of 2 days; tannic acid 1.53% (w/w) and potassium nitrate 2.71% (w/w). After the optimization process, the tannase production increased 4.65-fold. Keywords : surface response methodology; enzyme; jamun
TL;DR: Analysis of the behavioral activities of Macrobrachium rosenbergii and its preference for colored shelters suggests that black, red and orange shelters may improve the animals' well-being in the culture since aggressive encounters would decrease, especially during the light phase.
Abstract: Current research analyzed the behavioral activities of Macrobrachium rosenbergii and its preference for colored shelters in male monosex, female monosex and mixed culture. Ten shrimps m -2 were maintained in eight 250-L aquaria. Three artificial shelters, colored red, black and orange, were placed in each aquarium. Four aquaria were maintained in light/dark photoperiod respectively between 6h00 am and 6h00 pm and between 6h00 pm and 6h00 am, whereas the other four aquaria were submitted to an inverted photoperiod. The animals were observed for 30 days by Focal Animal Method for 15 minutes, with instantaneous recording every 60 seconds, at six different instances within the light and dark phases. Preference for black shelters occurred in male monosex and mixed cultures, whereas red and orange shelters were the preference of female monosex. M. rosenbergii kept in the shelter mostly during the light phase in male monosex and mixed populations. Results suggest that black, red and orange shelters may improve the animals' well-being in the culture since aggressive encounters would decrease, especially during the light phase.
TL;DR: IAA is revealed as an alternative solvent for obtaining SPs from the red seaweed G. cornea, depending on the industry' usage criterion.
Abstract: The global demand for natural products from seaweeds has increased worldwide; however, no description of the use of isoamly alcohol (IAA) for obtaining of sulfated polysaccharides (SPs) has been reported. We investigated the efficiency of two precipitation methods (M) in obtaining SPs from the red seaweed Gracilaria cornea. SPs enzymatically isolated were concentrated with cetylpyridinium chloride (M I) or IAA (M II) and extracts were examined with regard to their yield, structural features and in vitro effects on the activated partial thromboplastin time (APTT) using normal human plasma and standard heparin (193 IU mg -1 ). Yield difference reached 12.99%. Quantitative determination of sulfate was similar between the two methods ( but extracts revealed different pattern on charge density by agarose gel electrophoresis. Whereas both extracts revealed as agarocolloids, alternative M II was also efficient for lipids, proteins and nucleic acids according to the infrared analysis. Extracts had virtually no effect on APPT (1.95 and 2 IU mg -1 for M I and M II, respectively). The results revealed IAA as an alternative solvent for obtaining SPs from the red seaweed G. cornea, depending on the industry' usage criterion.
TL;DR: The interaction of Atherinella brasiliensis caught in intertidal areas of the Paranagua Estuarine Complex with environmental parameters was described, with environmental variables that most influenced the distribution of age classes were temperature and salinity.
Abstract: Habitat use is different along the ontogenetic development of some species and may be influenced by environmental parameters. This study described the interaction of Atherinella brasiliensis caught in intertidal areas of the Paranagua Estuarine Complex with environmental parameters. We caught 10024 individuals between August 2010 and July 2011, with total mean length of 44.32 mm (SD ± 25.37 mm), variation range between 12 and 142 mm, and weight between 0.01 and 73 g, averaging 1.35 g (SD ± 2.66 g) and ages estimated between < 1 and 22 months. Significant differences were detected between sectors and periods for number of individuals and weight at capture, with higher mean values in the mean sector during the rainy period. The spatial and temporal distribution of ages was statistically different, individuals between < 1 and 3 months were more abundant in the sector 2 during the rainy period, and individuals older than 7 months were evenly distributed throughout the sampling area, and with higher mean abundance at the beginning and end of the dry period. Environmental variables that most influenced the distribution of age classes were temperature and salinity.
TL;DR: Two experiments were performed to assess the tolerance of fingerlings Astyanax altiparanae to water salinity and the parameters of water quality, mortality and blood glucose during transport.
Abstract: Two experiments were performed. The first aimed to assess the tolerance of fingerlings Astyanax altiparanae to water salinity. Fish were exposed to salinity of 0, 3, 6, 9, 12 or 15 g NaCl L -1 for 96 hours. The fish mortality was 0%, in the levels of 0, 3 and 6 g L -1 ; 75% in the level of 9 g L -1 and 100% at 12 and 15 g L -1 of common salt. The second experiment aimed to assess the parameters of water quality, mortality and blood glucose during transport. For this, A. altiparanae were stored in plastic bags at 22, 30 and 37 g of fish L -1 stocking densities and salinity of 0, 3, 6 and 9 g L -1 , for. Fish showed similar mortality levels in the different salinities and stocking densities. The increase in fish density reduced the dissolved oxygen levels and salinity decreased the pH. The blood glucose levels were higher in those fish with 0 g L -1 salinity and higher stocking densities. The addition of salt to the water reduces the stress responses of A. altiparanae during transport.
TL;DR: In this article, the authors evaluated the seasonal variation of the diameter increase of Vochysia divergens specimens in a seasonal floodable forest of the Northern Brazilian Pantanal.
Abstract: The Pantanal is the largest wetland in the world, characterized by high biodiversity, but large areas have been invaded by Vochysia divergens, a flood-adapted pioneer and native tree of the riparian forest and Brazilian Savanna. Seasonality in rainfall causes annual rhythms in the tree's physiology, in which climatic stress factors induce a cambial dormancy in trees and, in consequence, growth zones in the trunk. Current analysis evaluates the seasonal variation of the diameter increase of V. divergens specimens in a seasonal floodable forest of the Northern Brazilian Pantanal. Field sampling was conducted between January and December 2012. Air temperature, relative humidity and precipitation were measured at a micrometeorological station, water level was measured by graded tape, and soil water content was measured by a portable TDR sensor. Diameter growth was monitored by dendrometric bands and aboveground litter production was sampled by litter traps. The annual diameter increase was 4.0 mm. There was correlation between diameter increment and climate and phenology, with the highest increase during the flooding period and the lowest during the dry season and reproductive period. Climate and phenology affected the growth rhythm of V. divergens.
TL;DR: Sequencing of nuclear (tmo4c4, dlx2 and bmp4) and mitochondrial (cox1, cytb) loci were done from fish of the three species of the genus Cichla reported in the literature of the upper Parana River basin to provide molecular differentiation for the species.
Abstract: Peacock bass, a fish of the genus Cichla, is an exotic species from the upper river Parana floodplain in which the species Cichla kelberi and C. piquiti have been confirmed, coupled to the specie C. monoculus upstream in the Capivara and Taquarucu dams. The introduction of this genus has caused negative impacts on the diversity of native species. Current research prospects DNA sequences capable of distinguishing the three species and provide molecular data for the taxonomic characterization of the species in the upper Parana River basin. Sequencing of nuclear (tmo4c4, dlx2 and bmp4) and mitochondrial (cox1, cytb) loci were done from fish of the three species of the genus Cichla reported in the literature of the upper Parana River basin. Sequence analysis provided molecular differentiation for the species through the usage of loci cytb, dlx2 and cox1. Since the latter only distinguished C. piquiti from the other Cichla species, the loci bmp4 and tmo4c4 were not adequate to accomplish our aim.
TL;DR: Higher richness was observed in the plankton samples and higher densities of testate amoebae were reported among the aquatic vegetation during the dry season, and further researches on these protists, especially in Rio de Janeiro, should be undertaken.
Abstract: Four samplings were carried out during the dry and rainy seasons in 2014, in two biotopes (plankton and aquatic macrophytes) to assess the composition and species richness of testate amoebae community in a coastal stream in the state of Rio de Janeiro, Brazil. Results showed great representation of Difflugiidae, Centropyxidae, Lesquereusiidae and Arcellidae families. Higher richness was observed in the plankton samples and higher densities of testate amoebae were reported among the aquatic vegetation during the dry season. Current investigation is a pioneer study conducted in the Ubatiba stream. Further researches on these protists, especially in Rio de Janeiro, should be undertaken.
TL;DR: Serjania communis Cambess (Sapindaceae) is a plant with climbing habit and occurs relatively often in Parana State, Brazil and seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology.
Abstract: Serjania communis Cambess. (Sapindaceae) is a plant with climbing habit and occurs relatively often in Parana State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringa, Parana State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in length and brown color. Seedlings are epigeal phanerocotylar. The seedlings have a hairy hypocotyl, foliaceous cotyledons, reduced epicotyl, and two opposite eophylls. The root is diarch, the hypocotyl shows root-stem transition structure, stem epicotyl, and dorsiventral and hypostomatous cotyledons and eophylls. 'Tirodendros' with 45 days of age do not develop cambial variant.
TL;DR: Results showed that the height was greater in shade environments, and the greater the available light, the greater was the number of side branches and C. madagascariensis has warranted success during the initial growth under different shadings.
Abstract: The invasion by Cryptostegia madagascariensis causes economic and environmental problems in Northeastern Brazil. Current study evaluates the initial growth of C. madagascariensis on light gradient. The experiment used 0, 30, 50 and 70% shading treatments arranged in a completely randomized design and evaluated in four periods, namely, 35, 50, 65 and 80 days. Height, absolute growth rate, relative growth rate, number of side branches, number of leaves, leaf area, specific leaf area, leaf area ratio, root mass ratio, stem mass ratio, leaf mass ratio and leaf area/root mass ratio were evaluated. Results showed that the height was greater in shade environments, and the greater the available light, the greater was the number of side branches. C. madagascariensis is able to change the leaf area, specific leaf area and biomass allocation in different shadings. Since C. madagascariensis varies growth forms and performs morphological adjustments to increase light uptake, the plant has warranted success during the initial growth under different shadings.
TL;DR: In this paper, the authors evaluated the antimicrobial activity of aqueous and hydroalcoholic extracts from Senna occidentalis (L.) Link, a perennial shrub native to South America and indigenous to tropical regions throughout the world.
Abstract: Senna species have been widely used by American, African and Indian ethic groups mainly in the treatment of feebleness, constipation, liver disorders and skin infections. Senna occidentalis (L.) Link is a perennial shrub native to South America and indigenous to tropical regions throughout the world. Current study evaluated the antimicrobial activity of aqueous and hydroalcoholic extracts from S. occidentalis prepared from different parts of the plant. Antimicrobial activity was assessed against standard pharmaceutical microorganisms by spectrophotometry and microdilution technique. Escherichia coli was sensitive only to compounds extracted from seeds which may be proteinaceous. A broader antimicrobial spectrum was demonstrated by the hydroalcoholic extract of seeds, mostly against Pseudomonas aeruginosa. The in vitro toxicity using mouse fibroblasts indicated that the extract might be a biocompatible ingredient for topical formulations, while the hydroalcoholic extract of aerial parts demonstrated to be potentially cytotoxic.
TL;DR: This study aimed to evaluate the toxicity of Ponceau 4R food dye on the cell cycle in root meristematic cells of Allium cepa L. at three concentrations: high, low and moderate.
Abstract: This study aimed to evaluate the toxicity of Ponceau 4R food dye on the cell cycle in root meristematic cells of Allium cepa L. at three concentrations: 0.25, 0.50 and 0.75 g L -1 , at exposure times of 24 and 48 hours. For each concentration, we used a set of five onion bulbs that were first rooted in distilled water and then transferred to their respective concentrations. Radicles were collected and fixed in acetic acid (3:1) for 24 hours. The slides were mounted with the crushing technique and stained with 2% acetic orcein. Cells were analyzed throughout the cell cycle, totaling 5,000 cells for each control and exposure time. The calculated mitotic indices were subjected to the Chi-square test (p < 0.05). From the results, we observed that the concentrations of 0.25 and 0.50 g L -1 at the 48-hour exposure, and the concentration of 0.75 g L -1 , the two exposure times time significantly reduced (p < 0.05) the cell division rate. Importantly, all the three concentrations at the two exposure times tested caused cellular aberrations in significant numbers in this testing system. Therefore, under the conditions studied, the Ponceau 4R was cytotoxic.
TL;DR: Seeds originate from anatropous, unitegmic and tenuinucellate ovules and the testa consists of crushed and thin-walled cells in almost all of the species studied herein, except for Elephantopus mollis and Parthenium hysterophorus, which showed exotesta cells with U-shaped thickening.
Abstract: Studies on seed structure of Asteraceae have received little attention of botanists. Seed structure in Asteraceae is analyzed to evaluate the usefulness of characters in the separation of species through the analysis of nine weedy species. Seeds originate from anatropous, unitegmic and tenuinucellate ovules. The partial collapse of the developing seed coat is a common characteristic in the Asteraceae species studied. The testa consists of crushed and thin-walled cells in almost all of the species studied herein, except for Elephantopus mollis and Parthenium hysterophorus, which showed exotesta cells with U-shaped thickening. The analysis revealed high uniformity in seed characters.