Water Management Interventions, Organic Fertilization, and Harvest Time in Dry Land in the Biosaline Production of Cactus Pear.

Brackish water can promote physicochemical changes in the soil. Aiming to mitigate the effect of excess salts in the soil, the use of organic matter promotes restructuring. The aim was to evaluate the productive and nutritional characteristics of cactus pear under different brackish water depths (ID) and levels of organic matter (OM). A factorial arrangement of 4 × 4 × 4 with four replications was utilized. Plots consisted of ID (0, 12, 20, and 28% reference evapotranspiration-ETo), and subplots were composed of OM levels (0, 15, 30, and 45 t/ha) and days after planting (DAP; 180, 270, 360, and 450 days). The growth, yield, and chemical composition of cactus pear were affected by ID and OM and/or by their interaction. The regular and increasing application of ID from 192 to 456 mm/year and a rainfall of 110 mm/year in cactus pear crops in biosaline systems improves the growth, freshness, dry matter yields, accumulation capacity per unit area, and chemical composition of cactus pear. The increase in OM up to the range from 30 to 45 Mg/ha linearly increases the agronomic performance of cactus pear. Biosaline systems with cactus pear should be adopted with the combined use of regular supplementary ID and OM, measuring at 304 mm/year and 45 Mg/ha, respectively.

Ciliate diversity in rodrigo de freitas lagoon (Rio de Janeiro, Brazil) from an integrative standpoint.

The Rodrigo de Freitas Lagoon is a highly eutrophic lacustrine system and has one of the longest histories of exploration and anthropic alteration in Brazil. Despite its relevance, limited studies explored the diversity of micro-eukaryotes in the lagoon. Ciliates (Alveolata, Ciliophora) are overlooked in environmental microbiology, especially in tropical and subtropical ecosystems, resulting in limited knowledge about their diversity and functional relevance in South American habitats, particularly in coastal lagoons. To fill this gap, here we investigated the diversity of ciliates in a brackish coastal lagoon in an urban area of Rio de Janeiro, Brazil, applying and comparing the performance of morphological and metabarcoding approaches. The metabarcoding analysis, based on high-throughput sequencing of the hipervariable region V4 of the 18S rRNA genes detected 37 molecular operational taxonomic units (MOTUs) assigned to Ciliophora, representing only about a half (56.9%) of the diversity detected by microscopy, which counted 65 ciliate morphotypes. The most representative classes in both approaches were Spirotrichea and Oligohymenophorea. The metabarcoding analysis revealed that 35.3% of the ciliate MOTUs had less than 97% similarity to available sequences in the NCBI database, indicating that more than one-third of these MOTUs potentially represents still not represented or undescribed ciliate species in current databases. Our findings indicate that metabarcoding techniques can significantly enhance the comprehension of ciliate diversity in tropical environments, but the scarcity of reference sequences of brackish ciliates in molecular databases represents a challenge to the taxonomic assignment of the MOTUs. This study provides new insights into the diversity of ciliates in a threatened coastal lagoon, revealing a vast array of still unknown and rare ciliate taxonomic units in tropical environments.

Foliar Applications of Salicylic Acid on Boosting Salt Stress Tolerance in Sour Passion Fruit in Two Cropping Cycles.

Brazil stands out as the largest producer of sour passion fruit; however, the water available for irrigation is mostly saline, which can limit its cultivation. This study was carried out with the objective of evaluating the effects of salicylic acid in the induction of tolerance in sour passion fruit to salt stress. The assay was conducted in a protected environment, using a completely randomized design in a split-plot scheme, with the levels of electrical conductivity of the irrigation water (0.8, 1.6, 2.4, 3.2, and 4.0 dS m-1) considering the plots and concentrations of salicylic acid (0, 1.2, 2.4, and 3.6 mM) the subplots, with three replications. The physiological indices, production components, and postharvest quality of sour passion fruit were negatively affected by the increase in the electrical conductivity of irrigation water, and the effects of salt stress were intensified in the second cycle. In the first cycle, the foliar application of salicylic acid at concentrations between 1.0 and 1.4 mM partially reduced the harmful effects of salt stress on the relative water content of leaves, electrolyte leakage, gas exchange, and synthesis of photosynthetic pigments, in addition to promoting an increase in the yield and quality parameters of sour passion fruit.

Morphophysiology and production of bell pepper grown under salt stress and salicylic acid foliar application / Morfofisiologia e produção de pimentão cultivado sob estresse salino e aplicação foliar de ácido salicílico

Considering the relevance of bell pepper and the limitations imposed by the deleterious effects of salt stress, especially in semi-arid regions, it is extremely important to establish strategies that can facilitate the use of saline water in vegetable production. In this scenario, this study aimed to evaluate the effect of the frequency of foliar application of salicylic acid on the morphophysiology and production of the bell pepper cv. "All Big" irrigated with saline water. The study was conducted at a greenhouse in Campina Grande - PB. The treatments were distributed in a completely randomized design and set up in a 4 × 4 factorial arrangement with three replications, corresponding to four application frequencies of salicylic acid (F1- No application of salicylic acid, F2 - Weekly application, F3- fortnightly application, and F4- monthly application) and four levels of electrical conductivity of irrigation water - ECw (0.8, 1.6, 2.4 and 3.2 dS m-1). The fortnightly application of salicylic acid at a concentration of 1.0 mM mitigated the effects of salt stress on the morphophysiology and production components of bell pepper cv. All Big cultivated with ECw of up to 2.4 dS m-1, which reinforces the hypothesis that salicylic acid can act as a signaling molecule and reduce the effects of saline stress in bell pepper, enabling the use of brackish water in agricultural activity, mainly in semi-arid regions of northeastern Brazil, which have a shortage of fresh water.

Considerando a relevância da cultura do pimentão e as limitações impostas pelos efeitos deletérios do estresse salino, principalmente em regiões semiáridas, é de suma importância o estabelecimento de estratégias que possam viabilizar o uso de águas salinas na produção de olerícolas. Neste contexto, objetivou-se com o presente estudo, avaliar o efeito da frequência de aplicação foliar de ácido salicílico sobre a morfofisiologia e a produção de pimentão cv. All Big irrigado com águas salinas. O estudo foi conduzido em casa de vegetação, em Campina Grande - PB. Os tratamentos foram distribuídos em delineamento inteiramente casualizados, em esquema fatorial de 4 × 4, com 3 repetições, sendo quatro frequências de aplicação de ácido salicílico (F1- Sem aplicação de ácido salicílico, F2 - Aplicação semanal, F3- quinzenal e F4- mensal) e quatro níveis de condutividade elétrica da água de irrigação - CEa (0,8, 1,6, 2,4 e 3,2 dS m-1). A aplicação quinzenal de ácido salicílico na concentração de 1,0 mM amenizou os efeitos do estresse salino sobre a morfofisiologia e os componentes de produção do pimentão cv. All Big cultivado com CEa de até 2,4 dS m-1, o que reforça a hipótese que o ácido salicílico pode atuar como uma molécula sinalizadora e reduzir os efeitos do estresse salino no pimentão, viabilizando o uso de água salobra na atividade agrícola, principalmente em regiões semiáridas do nordeste brasileiro, que possui escassez de água doce.

Quantification of infectious Human mastadenovirus in environmental matrices using PMAxx-qPCR.

Molecular methodologies providing data on viral concentration and infectivity have been successfully used in environmental virology, supporting quantitative risk assessment studies. The present study aimed to assess human mastadenovirus (HAdV) intact particles using a derivative of propidium monoazide associated with qPCR (PMAxx-qPCR) in aquatic matrices. Initially, different concentrations of PMAxx were evaluated to establish an optimal protocol for treating different naturally contaminated matrices, using 10 min incubation in the dark at 200 rpm at room temperature and 15 min of photoactivation in the PMA-Lite™ LED photolysis device. There was no significant reduction in the quantification of infectious HAdV with increasing concentration of PMAxx used (20 µM, 50 µM, and 100 µM), except for sewage samples. In this matrix, a reduction of 5.01 log of genomic copies (GC)/L was observed from the concentration of 50 µM and revealed 100% HAdV particles with damaged capsids. On the other hand, the mean reduction of 0.51 log in stool samples using the same concentration mentioned above demonstrated 83% of damaged particles eliminated in the stool. Following, 50 µM PMAxx-qPCR protocol revealed a log reduction of 0.91, 0.67, and 1.05 in other samples of raw sewage, brackish, and seawater where HAdV concentration reached 1.47 × 104, 6.81 × 102, and 2.33 × 102 GC/L, respectively. Fifty micrometers of PMAxx protocol helped screen intact viruses from different matrices, including sea and brackish water.

Methods of application of salicylic acid as attenuator of salt stress in cherry tomato / Métodos de aplicação de ácido salicílico como atenuantes do estresse salino em tomateiro cereja

Salt stress caused by excess salts present in irrigation water, is one of the biggest barriers in agricultural production, especially in semi-arid regions. Thus, the use of substances, such as salicylic acid, that minimize the deleterious effects of salinity on plants can be an alternative to ensure satisfactory production. In this context, the objective of this study was to evaluate the effects of different methods of application of salicylic acid on the growth, production and water use efficiency of cherry tomato plants under salt stress. The study was conducted in a greenhouse, using an Entisol soil with a sandy loam texture. The treatments were distributed in a completely randomized design, in a 2×4 factorial arrangement, corresponding to two levels of electrical conductivity of irrigation water - ECw (0.6 and 2.6 dS m-1) and four methods of application of salicylic acid (Control - without application of SA; via spraying; via irrigation and via spraying and irrigation), with five replicates and one plant per plot. The salicylic acid concentration used in the different methods was 1.0 mM. Application of salicylic acid via foliar spraying increased the growth, production and water use efficiency of cherry tomato plants. The salt stress induced by the electrical conductivity of 2.6 dS m-1 was attenuated by the foliar application of salicylic acid. The use of water of 2.6 dS m-1 associated with the application of salicylic acid via irrigation water further intensified the adverse effects of salinity on cherry tomato plants.

O estresse salino ocasionado pelo excesso de sais presentes na água de irrigação, é um dos maiores entraves para a produção agrícola, sobretudo em regiões semiáridas. Assim, a utilização de substâncias, como o ácido salicílico, que minimizem os efeitos deletérios da salinidade sobre as plantas pode ser uma alternativa para garantir uma produção satisfatória. Neste contexto, objetivou-se com este trabalho avaliar os efeitos de diferentes métodos de aplicação de ácido salicílico sobre o crescimento, a produção e a eficiência do uso da água de plantas de tomate cereja sob estresse salino. O estudo foi conduzido em casa de vegetação, utilizando-se de um solo Entisol de textura franco-arenosa. Os tratamentos foram distribuídos em delineamento inteiramente casualizados, em arranjo fatorial 2×4, sendo duas condutividades elétricas da água de irrigação - CEa (0,6 e 2,6 dS m-1) e quatro métodos de aplicação de ácido salicílico (Testemunha - sem aplicação de AS; via pulverização; via irrigação e pulverização e irrigação), com cinco repetições e uma planta por parcela. A concentração de ácido salicílico utilizada nos diferentes métodos foi de 1,0 mM. A aplicação de ácido salicílico via pulverização foliar, aumentou o crescimento, a produção de plantas de tomate cereja, e a eficiência do uso da água. O estresse salino induzido pela condutividade elétrica de 2,6 dS m-1 foi amenizado pela aplicação foliar de ácido salicílico. O uso de água de 2,6 dS m-1 associado a aplicação de ácido salicílico via lâmina de irrigação, intensificou os efeitos adversos da salinidade nas plantas de tomate cereja.

Temporal variation in infection levels and reproductive traits of the acanthocephalan Pseudoleptorhynchoides lamothei in the blue sea catfish Ariopsis guatemalensis (Günther, 1864).

Current data on reproductive biology and population dynamics of the acanthocephalans are scarce mainly in regions from the tropical Pacific. An analysis was done to identify possible factors that influence variation in infection levels of the acanthocephalan Pseudoleptorhynchoides lamothei Salgado-Maldonado, 1976 in its final host, the blue sea catfish Ariopsis guatemalensis (Günther, 1864), and describe its main reproductive traits. A total of 1,094 A. guatemalensis were collected from Tres Palos Lagoon from August 2014 to December 2015. Prevalence of P. lamothei varied from 1.47% to 38.33%, and mean abundance from 0.03 to 4.44 helminths per examined host. In female P. lamothei relative fecundity increased with total length. Temporal variations in P. lamothei infection levels were attributed mainly to changes in host feeding and reproductive behaviour in response to local environmental factors as climatic season, and variations in water temperature.

Biomethanation of invasive water hyacinth from eutrophic waters as a post weed management practice in the Dominican Republic: a developing country.

Anaerobic digestion of water hyacinth (Pontederia crassipes Mart.) from eutrophic water bodies could be a sustainable post weed management practice to generate bioenergy. Comparative analyses of the water quality, physicochemical characteristics, and biomethanation kinetics of water hyacinth from two sites with different water types (brackish versus freshwater) in the Ozama river, Dominican Republic, were conducted. Also, the energy produced from the anaerobic digestion and that consumed in harvesting was estimated. The highest non-structural components in the form of protein (18.8 ± 1.9%) and extractives (26.4 ± 0.1%) were found in brackish water hyacinth, whereas that from freshwater had the highest amount of holocellulose (41.2 ± 2.8%). Indicators of plant productivity, i.e., chlorophyll b and bulk density, were more than 30% higher in brackish than in freshwater hyacinth. The methane production rate in the digestion of water hyacinth from brackish water (22.5 N. L/kg VS added· day) was twice that from freshwater (10.0 N. L/kg VSadded· day). The higher nutrient content in the brackish water could have influenced the superior performance of water hyacinth from that source compared with that from freshwater. Overall, the maximum methane potential of the Ozama river water hyacinth was 399.2 ± 32.2 N. L CH4/kg VSadded. The estimated energy produced per ton of fresh biomass was 846.5 MJ, but only 57.9 MJ would be required for mechanical harvesting. The biomethanation of water hyacinth can mitigate weed management costs in developing countries.

Eficiência de um sistema piloto de dessalinização de água salobra / Efficiency of a brackish water desalination pilot system

RESUMO Com a escassez da disponibilidade de água doce e o aumento da demanda de água no mundo e no Brasil, uma das alternativas são os sistemas de dessalinização de água, que removem os sais das águas salobra ou salgada. Este estudo teve como objetivo avaliar a eficiência de um sistema piloto de dessalinização de água salobra a qual foi obtida a partir da mistura de águas do mar e de rio até atingir concentração de sólidos dissolvidos totais (SDT) de 1.500 mg.L-1. O sistema piloto de dessalinização, com capacidade de 1,0 m3.h-1, é composto de ultrafiltração (UF) e abrandamento como pré-tratamento à osmose reversa (OR). Foram realizadas análises de qualidade da água na entrada e saída das unidades de tratamento relativas a SDT, condutividade elétrica, turbidez, pH, cor aparente, alcalinidade, dureza total, cálcio, magnésio, cloreto, sulfato e temperatura. Foram avaliadas a pressão osmótica, o fluxo de filtração e a taxa de recuperação de água no sistema de OR. Com os resultados obtidos, conclui-se que a eficiência de remoção de SDT e condutividade foi de 99%. A UF foi eficiente na remoção de turbidez, enquanto a OR apresentou maiores eficiências de remoção de sais. O sistema piloto de tratamento foi capaz de remover todos os parâmetros estudados. A taxa de recuperação na OR foi de 74,64%.

ABSTRACT Considering the shortage of fresh water availability and an increased demand for water in the world, including Brazil, one of the alternatives for water supply are water desalination systems, which remove salts from brackish or seawater. The objective of this study was to evaluate the efficiency of pilot water desalination system treating brackish water which was obtained mixing fresh water and seawater up to reach 1,500 mg L-1 of total dissolved solids (TDS) concentration. The pilot desalination plant with production capacity of 1.0 m3 h-1 is composed of ultrafiltration (UF) and softener working as a pre-treatment to reverse osmosis (RO). Experiments were performed to analyze some water quality parameters as TDS, electrical conductivity, turbidity, pH, apparent color, alkalinity, total hardness, calcium, magnesium, chlorides, sulfates, and temperature. Osmotic pressure, filtration flow and water recovery rate were also measured for the RO. Analyzing the result obtained, it can be concluded that the efficiency of TDS removal and conductivity were 99%. UF was efficient in removing turbidity, whereas RO reached higher salt removal efficiencies. The pilot plant system could remove all water quality parameters studied. Recovery rate in RO was 74.64%.

The scale-dependent effect of environmental filters on species turnover and nestedness in an estuarine benthic community.

Environmental filtering is a major mechanism structuring ecological communities. However, it is still not clear how different abiotic drivers composing the environmental filter interact with each other to determine local species assemblage and create spatial patterns in species distribution. Here, we evaluated the effects of two strong and uncorrelated environmental variables (salinity and sediment properties) on the ß-diversity of an estuarine macrobenthic community while accounting for spatial effects. Our results show that the benthic community composition has a strong spatial structure along the estuary, which can be greatly explained by salinity and sediment variation. Salinity is most associated with species replacement (turnover), whereas sediment is more important for species loss (nestedness). However, the effects of sediment variation on nestedness are mainly detected at a smaller spatial scale (estuarine sectors), whereas the effects of salinity on species turnover are stronger as spatial scale increases (entire estuary). Our findings suggest that environmental filters can drive both turnover and nestedness components of ß-diversity, but that their relative importance depends on the spatial scale of investigation. Although abiotic drivers associated with detrimental effects (sediment) usually result in nestedness, larger spatial scales encompass abiotic drivers associated with different suitable conditions (salinity), increasing the relative importance of the replacement component of species ß-diversity.

Corrigendum: Gene and Blood Analysis Reveal That Transfer from Brackish Water to Freshwater Is More Stressful to the Silverside Odontesthes humensis.

[This corrects the article DOI: 10.3389/fgene.2018.00028.].

Acute toxicity of nitrate in Litopenaeus vannamei juveniles at low salinity levels / Toxicidade aguda do nitrato em juvenis de Litopenaeus vannamei em baixa salinidade

Different technologies have been developed to improve the performance of Litopenaeus vannamei in low salinity, mainly in super-intensive systems like recirculation and BFT (Biofloc Technology System) systems. However, there is an accumulation of toxic nitrogenous compounds to the shrimps such as nitrate, that at high concentrations and depending on the salinity of the culture water can be lethal. Acute toxicity tests allow to analyze the relationship between the compound and other abiotic or biotic variables. The aim of this research was to determine the acute toxicity and safety level of nitrate (N-NO3 -) for juveniles of L. vannamei at salinities of 5 and 10g.L-1. For salinity of 5g.L-1, a control and 5 treatments were tested, with nitrate concentrations of 100, 500, 1500, 2500 and 3500mg.L-1.For salinity of 10mg.L-1, a 4500mg.L-1nitrate concentration was added. Juveniles were exposed to concentrations during 24, 48, 72, 96 hours in static system. The Mean Lethal Concentration (LCC50) was calculated and the recommended safety level for L. vannamei cultivation is 60.05 and 127.61mg.L-1 of nitrate for salinities 5 and 10g.L-1, respectively.(AU)

Diferentes tecnologias foram desenvolvidas para melhorar o desempenho do Litopenaeus vannamei em baixa salinidade, principalmente em sistemas super intensivos como sistema de recirculação e BFT (Biofloc Technology System). No entanto, há um acúmulo de compostos nitrogenados tóxicos aos camarões, como o nitrato, que em altas concentrações e dependendo da salinidade da água pode ser letal. Os testes de toxicidade aguda permitem analisar a relação entre o composto e outras variáveis ​​abióticas ou bióticas. O objetivo deste trabalho foi determinar a toxicidade aguda e o nível de segurança do nitrato (N-NO3 -) em juvenis de L. vannamei nas salinidades de 5 e 10g.L-1. Para a salinidade de 5g.L-1, um controle e cinco tratamentos foram testados, com concentrações de nitrato 100, 500, 1500, 2500 e 3500mg.L-1. Para salinidade de 10mg.L-1, foi adicionada uma concentração de nitrato de 4500mg.L-1. Os juvenis foram expostos às concentrações durante 24, 48, 72, 96 horas em sistema estático. A Concentração Letal Média (CL50) foi calculada e o nível de segurança recomendado para o cultivo de L. vannamei é de 60,05 e 127,61mg.L-1 de nitrato para salinidadesde 5 e 10g.L-1, respectivamente.(AU)

Acute toxicity of nitrate in Litopenaeus vannamei juveniles at low salinity levels / Toxicidade aguda do nitrato em juvenis de Litopenaeus vannamei em baixa salinidade

ABSTRACT: Different technologies have been developed to improve the performance of Litopenaeus vannamei in low salinity, mainly in super-intensive systems like recirculation and BFT (Biofloc Technology System) systems. However, there is an accumulation of toxic nitrogenous compounds to the shrimps such as nitrate, that at high concentrations and depending on the salinity of the culture water can be lethal. Acute toxicity tests allow to analyze the relationship between the compound and other abiotic or biotic variables. The aim of this research was to determine the acute toxicity and safety level of nitrate (N-NO3 -) for juveniles of L. vannamei at salinities of 5 and 10g.L-1. For salinity of 5g.L-1, a control and 5 treatments were tested, with nitrate concentrations of 100, 500, 1500, 2500 and 3500mg.L-1.For salinity of 10mg.L-1, a 4500mg.L-1nitrate concentration was added. Juveniles were exposed to concentrations during 24, 48, 72, 96 hours in static system. The Mean Lethal Concentration (LCC50) was calculated and the recommended safety level for L. vannamei cultivation is 60.05 and 127.61mg.L-1 of nitrate for salinities 5 and 10g.L-1, respectively.

RESUMO: Diferentes tecnologias foram desenvolvidas para melhorar o desempenho do Litopenaeus vannamei em baixa salinidade, principalmente em sistemas super intensivos como sistema de recirculação e BFT (Biofloc Technology System). No entanto, há um acúmulo de compostos nitrogenados tóxicos aos camarões, como o nitrato, que em altas concentrações e dependendo da salinidade da água pode ser letal. Os testes de toxicidade aguda permitem analisar a relação entre o composto e outras variáveis ​​abióticas ou bióticas. O objetivo deste trabalho foi determinar a toxicidade aguda e o nível de segurança do nitrato (N-NO3 -) em juvenis de L. vannamei nas salinidades de 5 e 10g.L-1. Para a salinidade de 5g.L-1, um controle e cinco tratamentos foram testados, com concentrações de nitrato 100, 500, 1500, 2500 e 3500mg.L-1. Para salinidade de 10mg.L-1, foi adicionada uma concentração de nitrato de 4500mg.L-1. Os juvenis foram expostos às concentrações durante 24, 48, 72, 96 horas em sistema estático. A Concentração Letal Média (CL50) foi calculada e o nível de segurança recomendado para o cultivo de L. vannamei é de 60,05 e 127,61mg.L-1 de nitrato para salinidadesde 5 e 10g.L-1, respectivamente.

Techno-economic assessment of a multi-effect distillation plant installed for the production of irrigation water in Arica (Chile).

In the context of a regional Chilean project (FIC Taltape project, BIP code 30158422-0), a multi-effect distillation (MED) pilot plant has been built and installed in a small community in the north of Chile (Taltape, Arica) in order to supply treated water for agricultural and domestic purposes. The aim of this paper is to assess the techno-economic feasibility of this system for supplying water with the required quality to the population. The characterization of the feed water and the effluents from the MED pilot plant (distillate and brine), obtained during five months of operation, has been firstly performed. Then, the prediction of the operation of the water treatment system with solar energy has been carried out using a typical meteorological year and the design of a static solar field that cover the thermal energy needs of the water treatment plant. The annual simulations of the MED pilot plant operating with solar energy showed that the water needs can be mostly covered using a static solar thermal field with a total area of 113.2 m2, which would generate roughly 46% of the total heat required by the water treatment plant. The technical analysis has been completed with an exhaustive economic assessment. The specific water costs have been determined for the MED pilot plant and the scale factor when the productivity is increased up to 5000 m3/day has been evaluated. The cost of distillated water produced by the MED plant varied from 15.0 USD$/m3 for the 10 m3/day production capacity to 1.25 USD$/m3 when this variable is increased to 5000 m3/day.

Morphology and Phylogenetic Position of Gruberia lanceolata (Gruber 1884) (Ciliophora, Heterotrichea) from Rio de Janeiro, Brazil.

Ciliates of the genus Gruberia are poorly studied. Consequently, most species lack detailed morphological descriptions, and all gene sequences in GenBank are not classified at the species level. In this study, a detailed morphological description of a population of G. lanceolata from Brazil is presented, based on live and protargol-stained organisms. We also present the 18S rRNA gene sequence and the phylogenetic position of this species. The primary characteristics of G. lanceolata from the Maricá Lagoon are as follows: an elongate fusiform body 280-870 × 40-160 µm in size; rosy cortical granules; a peristome occupying approximately 1/3-1/2 of body length; an adoral zone comprising 115-330 membranelles; a paroral membrane in 35-50 fragments; and a moniliform macronucleus with 11-16 nodules. Based on our observations and data from pertinent literature, we suggest G. beninensis to be a junior synonym of G. lanceolata.

Notes on Halicyclops (Copepoda, Cyclopoida, Cyclopidae) from Colombia and the western Caribbean: a new record with a key to species of Group "B" sensu Rocha (1991) / Notas sobre Halicyclops (Copepoda, Cyclopoida, Cyclopidae) de Colombia y el Caribe occidental: un nuevo registro con una clave para las especies del Grupo "B" sensu Rocha (1991)

Three species of brackish waters microcrustaceans are herein recorded; they belong to the cyclopoid copepod genus Halicyclops and were collected from a coastal system in northern Colombia: H. exiguus Kiefer, 1934,H. venezuelaensis Lindberg, 1954, and H. hurlberti Rocha, 1991. The former has intraspecific variations that deserve further study. The finding of the latter species, previously known from the Eastern Tropical Pacific, represents a new record for Colombia and the Caribbean Sea Basin in the Northwestern Tropical Atlantic. With the finding of H. hurlberti the number of species of Halicyclops known from the Neotropical region and Colombia increases to 20 and 5, respectively. The regional diversity of the genus is probably underestimated. A key to species of the genus belonging to group "B" sensu Rocha (1991) is also provided.

Se registran tres especies de microcrustáceos de aguas salobres; son copépodos ciclopoides del género Halicyclops procedentes de un sistema costero en el norte de Colombia: H. exiguus Kiefer, 1934, H. venezuelaensis Lindberg, 1954 y H. hurlberti Rocha, 1991. La primera especie tiene una variación intraespecífica que merece estudios más profundos. El hallazgo de la última especie es conocida sólo en el Pacífico Tropical Oriental, representa un registro nuevo para Colombia y la cuenca del Mar Caribe en el Atlántico tropical noroccidental. Con el hallazgo de H. hurlberti, la cantidad de especies de Halicyclops reconocidas en la región Neotropical y Colombia aumenta a 20 y 5, respectivamente. La diversidad regional del género probablemente está subestimada. Se proporciona una clave para las especies del género que pertenecen al grupo "B" sensu Rocha (1991).

Genotypic characterization and assessment of infectivity of human waterborne pathogens recovered from oysters and estuarine waters in Brazil.

Waterborne, food-borne and sewage-borne pathogens are a major global concern, with the annual recurrence, most notably during the summer, of outbreaks of gastroenteritis of unconfirmed etiology associated with recreational activities in marine environments. The consumption of contaminated water-based foodstuffs is also related to outbreaks of human illness. The main goals of the present study were: i) to identify the genetic assemblages of Giardia duodenalis cysts in growing and depurated oysters destined for human consumption on the southern coast of São Paulo, Brazil; ii) to verify the main circulating G. duodenalis assemblages and their subtypes in different brackish waters used for the production of mollusks and for recreational purposes; iii) to track the contamination of growing and depurated oysters by the human adenovirus and identify the infectivity of adenoviral particles recovered from oysters before and after depuration; iv) to evaluate the occurrence and genotype of the free-living amoebae of the genus Acanthamoeba in brackish water and oysters from all the sites described above. Four sampling sites in the Cananeia estuary were selected to search for pathogenic and amphizoic protozoa (Giardia and Acanthamoeba respectively): site 1: oyster growth, site 2: catchment water (before UV depuration procedure), site 3: filter backwash (filtration stage of water treatment) and site 4: oyster depuration tank. Oysters at sites 1 and 4 were evaluated for the presence of adenovirus (HAdV). Analysis consisted of conventional microbiological as well as molecular methods. Giardia duodenalis were detected in all the water sites analyzed and the molecular analysis revealed that sub-assemblage AII was the most frequently distributed throughout the estuarine environment, although one sample was identified as belonging to the assemblage C. Acanthamoeba were also isolated from different locations of the estuarine area, and were detected at all the analyzed sites. The majority of isolates belonged to the T3 genotype, while the T4 genotype was identified once. The sequencing reaction of Giardia duodenalis revealed the contamination of three batches of depurated oysters by the sub-assemblage AII. With respect to viruses, seven batches of oysters (four growing and three depurated) were found to be harboring infectious HAdV particles when submitted to plaque assay. Overall, the results of the sequencing reactions combined with the plaque assay revealed that the isolates of Giardia duodenalis and the infectious HAdV particles identified in oyster tissues have the potential to infect humans and pose a threat if consumed raw or lightly cooked. This is the first report on the sub-assemblage AII identified in oysters which are submitted to a cleaning and disinfection procedure prior to human consumption in Brazil. Acanthamoeba specific genotypes were also identified for the first time in a recreational estuarine area in Brazil, contributing to knowledge of their molecular and environmental epidemiology, which is considered scarce even in marine and estuarine areas of the world.

Combined effects of temperature and salinity on the demographic response of Proales similis (Beauchamp, 1907) and Brachionus plicatilis (Müller, 1786) (Rotifera) to mercury.

The demographic response of the brackish-water rotifers Proales similis and Brachionus plicatilis to mercury (0.5, 2, 8 and 32 µg L-1 of HgCl2) at different salinity levels (10 and 20‰) and two temperature (25 °C and 32 °C) regimes were evaluated. Median lethal concentration (LC50) for P. similis and B. plicatilis was 10 and 16 µg L-1, respectively, showing that Proales similis was more sensitive to mercury than B. plicatilis. The rate of population increase (r) for both species was greater at 10‰ salinity and 32 °C (ranged from 0.6 to 0.95 d-1). The r-value decreased as the concentration of mercury in the medium increased. Regardless of the temperature, at lower salinity and higher mercury concentration (32 µg L-1), P. similis died within six days. The survivorship of P. similis and B. plicatilis was higher at 25 °C than at 32 °C (ranged from 5 to 8 and 7-13 d, respectively). Fecundity was higher at 32 °C than at 25 °C for both rotifers species. There was a significant effect of the interaction among salinity, temperature, and mercury in both species on the reproductive variables such as net and gross reproductive rates, generation time and the rate of population increase. Considering the sensitivity of P. similis, we suggest that this species be included in the list of marine bioassay organisms.

Gene and Blood Analysis Reveal That Transfer from Brackish Water to Freshwater Is More Stressful to the Silverside Odontesthes humensis.

Silversides are fish that inhabit marine coastal waters, coastal lagoons, and estuarine regions in southern South America. The freshwater (FW) silversides have the ability to tolerate salinity variations. Odontesthes humensis have similar habitats and biological characteristics of congeneric O. bonariensis, the most studied silverside species and with great economic importance. Studies revealed that O. bonariensis is not fully adapted to FW, despite inhabiting hyposmotic environments in nature. However, there is little information about stressful environments for cultivation of silverside O. humensis. Thus, the aim of this study was to evaluate the stress and osmoregulation responses triggered by the osmotic transfers on silverside O. humensis. Silversides were acclimated to FW (0 ppt) and to brackish water (BW, 10 ppt) and then they were exposed to opposite salinity treatment. Silverside gills and blood were sampled on pre-transfer (D0) and 1, 7, and 15 days (D1, D7, and D15) after changes in environmental salinity, the expression levels of genes atp1a3a, slc12a2b, kcnh1, and hspa1a were determined by quantitative reverse transcription-PCR for evaluation of osmoregulatory and stress responses. Furthermore, glycemia, hematocrit, and osmolality were also evaluated. The expression of atp1a3a was up- and down-regulated at D1 after the FW-BW and BW-FW transfers, respectively. Slc12a2b was up-regulated after FW-BW transfer. Similarly, kcnh1 and hspa1a were up-regulated at D1 after the BW-FW transfer. O. humensis blood osmolality decreased after the exposure to FW. It remained stable after exposure to BW, indicating an efficient hyposmoregulation. The glycemia had a peak at D1 after BW-FW transfer. No changes were observed in hematocrit. The return to the pre-transfer levels at D7 after the significant increases in responses of almost all evaluated molecular and blood parameters indicated that this period is enough for acclimation to the experimental conditions. In conclusion, our results suggest that BW-FW transfer is more stressful to O. humensis than FW-BW transfer and the physiology of O. humensis is only partially adapted to FW.

Produção de alface (Lactuca sativa) em efluentes de um cultivo de tilápias mantidas em sistema BFT em baixa salinidade / Lettuce (Lactuca sativa) production with effluent from a tilapia culture maintained in BFT and low salinity

No presente experimento verificou-se o efeito da salinidade no desempenho produtivo de diferentes cultivares de alface (Lactuca sativa) em um sistema de aquaponia utilizando a tecnologia de bioflocos. O experimento consistiu de dois sistemas independentes com duas salinidades: 0 ppt (DOCE) e 3 ppt (SAL). Foram estocados juvenis de tilápia (Oreochromis niloticus) em biomassa relativa de 6,1 kg m-3, e nas bancadas hidropônicas (tipo floating) foram mantidas três variedades de alface: roxa, lisa e crespa, na densidade de 20 plantas m-2. Os parâmetros zootécnicos dos peixes não apresentaram diferenças estatísticas entre os tratamentos, exceto o índice hepatossomático, que foi mais elevado em 3 ppt (4,35%) quando comparado ao registrado em 0 ppt (3,07%) (P<0,05). De maneira geral, a produtividade das variedades de alface foi superior em água doce (1,21 kg m-2) em relação à água salobra (0,8 kg m-2) (P<0,05). Considerando a maioria dos parâmetros fitotécnicos avaliados, os valores apresentados pela variedade roxa foi superior aos registrados para as variedades lisa e crespa. Já no tocante ao índice de qualidade de plantas (IQP), a variedade roxa em água salobra foi a que apresentou as melhores notas, com folhas mais íntegras e coloração mais intensa. Os resultados demonstraram que é possível integrar a criação de tilápia com a produção de alface roxa em sistemas de aquaponia com tecnologia de bioflocos e baixa salinidade.(AU)

This experiment evaluated the effect of salinity on growth performance of different lettuce cultivars (Lactuca sativa) in an aquaponics system with biofloc technology. The device contained two independent systems with two different salinities 0 ppt and 3 ppt. Were stored, Juvenile tilapia (Oreochromis niloticus) 6.1 kg m-3 and three varieties of lettuce: red leaf, smooth and crisp 20 plants m-2 in the floating system. All fish performance parameters showed no statistical differences, except for the hepatossomatic index, higher in 3 ppt (4.35%) versus (3.07%) in 0 ppt (P<0.05). In general, the productivity of lettuce cultivars were superior in fresh water (1.21 kg m-2) compare to brackish water (0.8 kg m-2) (P<0.05). In most phytotechnical parameters evaluated, the purple variety had better performance than the smooth and crisped varieties. In relation to plant quality index (IQP), purple variety in brackish water had the best score, presenting leafs with higher integrity and intense coloration. The results demonstrated that it is possible to integrate the production of red leaf variety in aquaponics systems with the technology of bioflocs in low salinity.(AU)