Responses of tomato hybrid cultivars to soil application of humic acid under greenhouse conditions

Abstract Responses of three tomato (Lycopersicon esculentum Mill.) hybrids viz. 'Luanova', 'Savarona' and 'Tessera' to various doses (0, 0.5, 1.0, 1.5 and 2.0 g L-1) of soil application of humic acid (HA) were evaluated in terms of plant growth, productivity and quality of fruits, under greenhouse conditions, during 2011-12 and 2012-13. In addition to improved quality characteristics, higher values for yield and yield components were recorded for tomato fruits harvested from plants of 'Tessera' cultivar compared to those harvested from other hybrids tested, regardless of growing seasons. Plants from 'Luanova' cultivar were, however, earlier in fruiting with higher number of fruits per plant. Soil application of HA presented positive effects on yield and physicochemical quality of tomato fruits irrespective of the dose of HA and the cultivar investigated, in both seasons. Soil application of HA at higher dose 1.5 g L-1 exhibited better results in all the three tomato cultivars tested, in terms of their vegetative and reproductive growth, and significantly improved the physicochemical quality of their fruits. Conclusively, the tomato hybrid 'Tessera' was found suitable for cultivation under greenhouse conditions while soil application of aqueous solution of HA @ 1.5 g L-1 substantially resulted in higher production of quality tomato fruits.

Resumo Respostas de três híbridos de tomate (Lycopersicon esculentum Mill.) viz. 'Luanova', 'Savarona' e 'Tessera' para várias doses (0, 0,5, 1,0, 1,5 e 2,0 g L-1) de aplicação de ácido húmico (AH) no solo foram avaliadas em termos de crescimento da planta, produtividade e qualidade de frutas, em casa de vegetação, durante 2011-12 e 2012-13. Além das características de qualidade melhoradas, valores mais elevados para o rendimento e os componentes do rendimento foram registrados para frutos de tomate colhidos de plantas do cultivar 'Tessera' em comparação com aqueles colhidos de outros híbridos testados, independentemente das estações de cultivo. As plantas do cultivar 'Luanova', no entanto, frutificaram mais cedo com maior número de frutos por planta. A aplicação de AH no solo apresentou efeitos positivos sobre a produtividade e a qualidade físico-química dos frutos de tomate, independentemente da dose de AH e do cultivar investigado, nas duas safras. A aplicação de HA no solo na dose maior de 1,5 g L-1 apresentou melhores resultados nos três cultivares de tomate testados, quanto ao crescimento vegetativo e reprodutivo, e melhorou significativamente a qualidade físico-química dos frutos. Conclusivamente, o híbrido de tomate 'Tessera' foi considerado adequado para cultivo em casa de vegetação, enquanto a aplicação no solo de solução aquosa de HA @ 1,5 g L-1 resultou substancialmente em maior produção de frutos de tomate de qualidade.

Evaluation of contact angle and mechanical properties of resin monomers filled with graphene oxide nanofibers

Abstract This in vitro study synthesized hybrid nanofibers embedded in graphene oxide (GO) and incorporated them into experimental resin composite monomers to evaluate their physical-mechanical properties. Inorganic-organic hybrid nanofibers were produced with precursor solutions of 1% wt. GO-filled Poly (d,l-lactide, PLA) fibers and scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) characterized the morphology and chemical composition of the spun fibers. Resin composite monomers were developed and a total of 5% nanofibers were incorporated into the experimental materials. Three groups were developed: G1 (control resin monomers), G2 (resin monomers/PLA nanofibers), and G3 (resin monomers/inorganic-organic hybrid nanofibers). Contact angle (n=3), flexural strength (n=22), elastic modulus (n=22), and Knoop hardness (n=6) were evaluated. The mean of the three indentations was obtained for each sample. The normality of data was assessed by QQ Plot with simulated envelopes and analyzed by Welch's method (p<0.05). Overall, SEM images showed the regular shape of nanofibers but were non-aligned. Compositional analysis from EDS (n=6) revealed the presence of carbon and oxygen (present in GO composition) and Si from the functionalization process. The results of contact angle (°) and hardness (Kg/mm2) for each group were as follow, respectively: G1 (59.65±2.90; 37.48±1.86a), G2 (67.99±3.93; 50.56±1.03b) and G3 (62.52±7.40; 67.83±1.01c). The group G3 showed the highest Knoop hardness values (67.83 kg/mm2), and the flexural strength of all groups was adversely affected. The experimental resin composite composed of hybrid nanofibers with GO presented increased hardness values and hydrophilic behavior.

Resumo Este estudo in vitro sintetizou nanofibras híbridas embebidas em óxido de grafeno (GO), incorporando-as à uma resina composta experimental de monômeros para avaliar suas propriedades físico-mecânicas. Nanofibras híbridas inorgânica-orgânicas foram produzidas com soluções precursoras de fibras poli (d, l-lactídeo, PLA) preenchidas com GO a 1% em peso e microscopia eletrônica de varredura (MEV) e espectroscopia de raio-X de energia dispersiva (EDS) caracterizaram a morfologia e composição química das fibras. Monômeros de resina composta foram desenvolvidos e um total de 5% de nanofibras foi incorporado aos materiais experimentais. Três grupos foram desenvolvidos: G1 (monômeros de resina controle), G2 (monômeros de resina/ nanofibras de PLA) e G3 (monômeros de resina/nanofibras híbridas inorgânico-orgânicas). Ângulo de contato (n=3), resistência à flexão (n=22), módulo de elasticidade (n=22) e dureza Knoop (n=6) foram avaliados. A média das três endentações foi obtida para cada amostra. A normalidade dos dados foi avaliada pelo QQ Plot com envelopes simulados e analisada pelo método de Welch (p<0,05). No geral, as imagens de MEV mostraram forma regular de nanofibras, mas não alinhadas. A análise composicional de EDS (n=6) revelou a presença de carbono e oxigênio (presentes na composição do GO) e Si resultante do processo de funcionalização. Os resultados do ângulo de contato (°) e dureza (Kg/mm2) para cada grupo foram os seguintes, respectivamente: G1 (59,65±2,90; 37,48±1,86a), G2 (67,99±3,93; 50,56±1,03b) e G3 (62,52±7,40; 67,83±1,01c). G3 apresentou os maiores valores de dureza Knoop (67,83 kg/mm2), e a resistência à flexão de todos os grupos foi prejudicada. A resina composta experimental composta por nanofibras híbridas com GO apresentou maiores valores de dureza e comportamento hidrofílico.

Nursery performance of potentially promising rootstocks for citriculture in the south of Brazil / Desempenho em viveiro de porta-enxertos potencialmente promissores para a citricultura do sul do Brasil

ABSTRACT: Diversification of rootstock varieties, with consequent reduction in phytosanitary risks, has great importance to the sustainability of citrus cultivation in the south of Brazil. This study evaluated the performance of 42 rootstocks in the nursery phase to generate 'Valencia Late' sweet orange seedlings. Therefore, nucellar seedlings from the rootstocks under study were analyzed in relation to plant height, stem diameter, mortality rate and percentage of bud set after grafting. The experimental design was completely randomized with four replications of 20 sample units. Not adapted genotypes had high mortality rates, and the ones of both hybrids LCR x CTSW - 009 and LVK x LCR - 038 were 100% and 90%, respectively. Other 13 genotypes had mortality rates above 30%, and 'Sunki' mandarin was the female genitor of ten of them. 'Swingle' citrumelo was the rootstock with the highest development (plant height and stem diameter), associated with low mortality rate. In relation to the other rootstocks, the best results were the fast grafting diameter, associated with low mortality rate obtained by hybrids HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, and citrandarins 'Indio', 'Riverside' and 'San Diego', as well as Trifoliate orange and 'Rangpur' lime. In addition to Trifoliate orange, which is widely used in Rio Grande do Sul, these rootstocks have great potential in citriculture in the south of Brazil.

RESUMO: A diversificação do uso de variedades porta-enxerto, com a consequente redução de riscos fitossanitários, é de fundamental importância para a sustentabilidade da citricultura do Sul do Brasil. O objetivo deste trabalho foi avaliar o comportamento de 42 porta-enxertos na formação de mudas de laranjeira 'Valência Late' em fase de viveiro. Nesse sentido, seedlings (plantas oriundas da germinação de sementes) nucelares dos porta-enxertos estudados foram avaliados relativamente aos caracteres altura da planta, diâmetro do caule, taxa de mortalidade e percentagem de pegamento de borbulhas após a enxertia. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 20 unidades amostrais. Genótipos não adaptados tiveram altas taxas de mortalidade, os híbridos LCR x CTSW - 009 e LVK x LCR - 038 apresentaram 100% e 90% de mortalidade, respectivamente. Mais 13 genótipos apresentaram mortalidade superior a 30%, destes, dez têm como parental feminino a tangerineira 'Sunki'. O citrumelo 'Swingle' foi o porta-enxerto que apresentou maior desenvolvimento (altura da planta e diâmetro do caule), associado a uma baixa taxa de mortalidade. Quanto aos demais porta-enxertos, destacaram-se por atingir rapidamente o diâmetro de enxertia, associado a baixa taxa de mortalidade, os híbridos HTR - 053, LRF x (LCR x TR) - 005, CLEO x TRBN - 245, CLEO x TRSW - 287, citrandarins 'Indio', 'Riverside' e 'San Diego', assim como o limoeiro 'Cravo' e o Trifoliata. Além do Trifoliata, amplamente utilizado no Rio Grande do Sul, estes porta-enxertos são promissores para a citricultura do Sul do Brasil.

Desenvolvimento de inibidores duais de histona desacetilase 6 (HDAC6) e tirosina quinase (TQ) com vistas ao tratamento do câncer / Design of histone deacetylase 6 (HDAC6) and tyrosine kinase (TK) dual inhibitors for cancer treatment

Câncer é a denominação atribuída a um conjunto de doenças que são responsáveis pela segunda maior causa de morte no Brasil e no mundo. A quimioterapia figura entre uma das estratégias utilizadas para o tratamento e cura do câncer, sendo amplamente empregada em estratégias terapêuticas isoladas, ou em associação à radioterapia e cirurgia. A enzima histona desacetilase 6 (HDAC6) é responsável por desacetilar a cadeia lateral de N-acetillisinas em -tubulinas, desempanhando papel crítico na dinâmica do citoesqueleto celular, estando superexpressa em uma série de neoplasias. Neste sentido, na última década os receptores tirosina quinase (TQ) foram os principais alvos de fármacos aprovados para o tratamento do câncer e de doenças autoimunes e continuam atraindo a atenção de grupos de pesquisa dada a exorbitante diversidade do quinoma humano. É sabido que a monoterapia seja com inibidores de HDAC, seja com inibidores TQ, apresenta problemas de toxicidade, reações adversas, ineficácia, resistência e/ou recidiva. Diversos estudos relatam o desenvolvimento de inibidores duais de HDAC-TQ, almejando tanto a simplificação do tratamento, quanto sinergismo terapêutico e redução de efeitos adversos. Assim, o presente trabalho apresenta o planejamento, síntese e avaliação da citotoxicidade de inibidores duais, potencialmente seletivos para HDAC6 e receptores TQ. No total, 23 compostos foram sintetizados entre 2 a 4 etapas. Todos os compostos finais foram caracterizados por RMN (1H e 13C) e espectrometria de massas de alta resolução (HRMS). A citotoxicidade foi determinada pelo ensaio de MTT, em linhagens derivadas de tumores sólidos (HCT116 e MCF-7) e hematológicos (Jurkat e Namalwa). Os compostos apresentaram citotoxicidade em concentrações micro e nanomolares em todas as linhagens testadas, sendo que a linhagem MCF-7 foi a mais resistente à ação dos compostos, e as linhagens hematológicas foram as mais sensíveis. Os inibidores 4d-f foram os mais ativos na triagem por MTT, com IC50 iguais a 20, 30 e 50 nM, respectivamente, em células Jurkat. Estudos mecanísticos do efeito citotóxico indicaram que os compostos 4d-f exercem atividade de forma tempo-dependente, e majoritariamente por ação antiproliferativa, embora estímulos apoptóticos também tenham sido observados nos estudos. Simulações de ancoramento molecular (docking) e de relação entre as estruturas químicas dos compostos e suas respectivas atividades biológicas (REA) permitiram identificar padrões moleculares, propriedades físico-químicas e eletrônicas que potencialmente possuem relação com a atividade biológica dos compostos, permitindo futuras otimizações do arcabouço molecular desta série de compostos. Tomados em conjunto, os resultados deste trabalho revelam o potencial terapêutico de inibidores duais de HDAC6-TQ. Notadamente, os compostos apresentados aqui podem ser os primeiros potenciais inibidores duais de HDAC6-TQ a serem reportados na literatura

Cancer is the name of a series of diseases that are the second main cause of death in Brazil and worldwide. Chemotherapy is one of the main strategies to treat and cure cancer, and has been widely applied as a single therapeutic agent, and in association with radiotherapy and surgery. Histone deacetylase 6 (HDAC6) deacetylates N-acetyllysine side chains of tubulin, playing crucial role on cytoskeletal dynamics, and could be overexpressed in several cancers. Tyrosine kinase receptors (TK) have been the main targets of FDA-approved drugs through the last decade for both cancer and autoimmune diseases, and have been attracting special attention of research groups due to the exorbitant diversity of the human kinome. It is known that either HDAC or TK single therapy have toxicity issues, adverse effects, inefficacy, resistance and/or recidive. Therefore, many studies report the design of HDAC-TK dual inhibitors aiming simpler treatments, synergism of action and side effects reduction. Herein, the design, synthesis and cytotoxic evaluation of dual and selective HDAC6-TK inhibitors are presented. A total of 23 compounds were designed and synthesized through 2 to 4 steps. All final compounds were characterized by 1H/13C NMR and high-resolution mass spectrometry (HRMS). The cytotoxicity of compounds was determined by MTT assay for both solid (HCT116 and MCF-7 cells) and hematological cancers (Jurkat and Namalwa cells). Compounds exhibited micro and nanomolar ranges of cytotoxicity for all cell lines tested. MCF-7 cells were the most resistant against the treatment, and hematological cells were more susceptible to the cytotoxic effect of the compounds. Compounds 4d-f were the most actives in the MTT screening against Jurkat cells (IC50 = 20, 30 and 50 nM, respectively). Mechanistic studies regarding the cytotoxic effects of 4d-f indicated that the compounds induced cell death in a time-dependent manner mainly via cytostatic activity even though apoptotic stimuli were observed also. Molecular docking and structure-activity relationships (SARs) allowed the identification of molecular patterns, and physicochemical and electronic properties that potentially modulate the biological activity of these compounds, allowing further optimizations of the molecular scaffold for these series of compounds. Taken together, the results of this study reveal the therapeutic potential of HDAC6-TK dual inhibitors. Noteworthy, the compounds reported herein could be the first HDAC6-TK dual inhibitors ever reported in literature

Autoatención y automedicación: reflexiones y retos desde la ontología del ser social / Self-care and Self-medication: Reflections and Challenges from the Ontology of a Social Being

Resumen La autoatención, aunque la mayor parte del tiempo se considera como un problema de salud pública, también puede ser considerada un acto de empoderamiento y contrahegemonía; sobretodo, si se toma en consideración la autonomía de los individuos para aliviar y comprender una enfermedad o padecimiento. En el contexto institucional de la atención de la salud, la autoatención se convierte en un espacio donde conviven diversos tipos de instituciones, saberes y representaciones. Por lo anterior, los actores sociales que practican autoatención resignifican y descentralizan la práctica médica y el conocimiento científico. Una parte de esas prácticas es la automedicación. El objetivo de este artículo es explicar cómo la autoatención y la automedicación son parte de la vida cotidiana de los individuos, y cómo esta práctica no se limita a un ámbito médico; en cambio, propone ubicar la práctica de autoatención como parte de una discusión más amplia que tiene base en la ontología del ser social expresada en categorías como el hogar y lo cotidiano. Se plantean retos que requieren pensar en la autoatención y la automedicación desde un pluralismo disciplinar que va desde la antropología y la sociología médica, hasta la economía de la salud, la psicología y la farmacología. Se reflexiona en el hogar como primer espacio real de atención, donde se expresan prácticas laicas y tácticas microsubersivas; el cotidiano como un reflejo de aspectos históricos, sociales, coyunturales, políticos, ambientales, entre otros. Se plantea un modelo atención más allá del consultorio, lo vestal o privado, trasciende la idea del antiguo consultorio.

Abstract Self-care, although most of the time is seen as a public health problem, may also be considered an act of empowerment and counter-hegemony if it takes into consideration the autonomy of social groups to self-understand and self-alleviate a disease or illness. When it comes to the institutional health care context, self-care becomes a space where various types of institutions, knowledge, and representations coexist. Due to the foregoing, social actors practicing self-care re-signify and decentralize medical practice and scientific knowledge, by means of their practice of self-medication. The objective of this article is to explain how selfcare and self-medication are part of an individual's everyday life, and how this practice is not limited to the medical realm; instead, it proposes to locate self-care practices as part of larger discussion about the ontology of a social being, expressed in categories such as the home and the everyday. But doing that poses a series of challenges that require thinking about self-care and self-medication from a perspective of disciplinary pluralism, ranging from anthropology and medical sociology to health economics, psychology and pharmacology. Home is reflected as the first real space of attention, where secular practices and micro-subversive tactics are expressed; also, everyday life as a reflection of historical, social, political and environmental aspects, among others. A care model is proposed beyond the office and the private, transcending the classical idea of a doctor's office.

Synthesis of ureasil-polyether film forming materials by using environmentally friendly solvent

Organic inorganic hybrids present several advantages as drug release systems, such as: high flexibility, high mechanical and thermal resistance, transparency, and low water solubility. These hybrids are synthesized through a chemical route named sol-gel that usually uses as solvente tetrahydrofuran (THF). Objetives: To develop film formers from hybrid materials replacing THF with ethanol, a less toxic solvent for skin application and for the environment. Methods: Four polymers were used: two based on polyethylene oxide (PEO) with molecular weight of 500 and 1900 g mol-1 and two based on polypropylene oxide (PPO), with molecular weight of 400 and 2000 g mol-1. The structural analysis was performed by FTIR, 1H-NMR and 29Si-NMR, and the thermal-mechanical analysis by DSC and TG-DTA. Results: The results of the thermo-mechanical analysis revealed that the solvent replacement did not affect the thermal stability and flexibility of the di-ureasil hybrid. Conclusions: Structural characterization confirmed the formation of hybrids both in THF and in ethanol. Therefore, ethanol is an excellent solvent for the synthesis of these hybrid matrices, since it allows obtaining the same material without changing its characteristics, with some advantages, however, over THF. Furthermore, this paper describes the efficiency of ethanol as a solvent, which is environmentally friendly, to replace THF in the physical-chemical characteristics of these filming former materials.

Coffea canephora breeding: estimated and achieved gains from selection in the Western Amazon, Brazil / Melhoramento do Coffea canephora: ganhos de seleção estimados e realizados na Amazônia Ocidental

ABSTRACT: Gain from selection is an important criterion in quantifying the efficiency of breeding programs. This study quantified the selection gain estimated under experimental conditions and realized gain achieved in the field, seeking to interpret the efficiency of the Coffea canephora selection. For that purpose, we considered experiments that began in 2004 with directed hybridizations to obtain new hybrid progenies. From a breeding population composed of 288 hybrid individuals, 12 genotypes were selected in experimental conditions from 2005 to 2012, with amplitude in the estimated gains from 127.70 to−19.19%. Those genotypes were evaluated from 2012 to 2018 in clonal tests in four environments of the Western Amazon. The environment that exhibited the greatest correlation between the predicted genetic values and the realized genetic gain observed in the field was the environment of Ouro Preto do Oeste, RO (0.67), the location in which the plants were selected, followed by the environments of Alta FlorestaD´Oeste, RO (0.44), Rio Branco, AC (0.43), and Porto Velho, RO (0.37).Experimental conditions showed that the effect due to dominance deviations was approximately three times greater than the additive effect. Nine clones exhibited higher genetic gains in the experimental conditions and at field, and two clones exhibited lower estimated gains and lower field performance.The clone G17-P7 exhibited high genetic gain under experimental conditions and low field performance. The selection in experimental conditions was positively correlated with plant performance in the field (r=0.55), which allows reduction of the original breeding population to a set of more promising clones to be grown in multiple environments, optimizing time and resources.

RESUMO: O ganho com a seleção é um dos critérios mais importantes para avaliar a eficiência de programas de melhoramento de plantas. O objetivo desse trabalho é quantificar a associação entre o ganho de seleção estimado em condições experimentais e o ganho de seleção realizado em campo, buscando quantificar a eficiência do melhoramento do Coffea canephora. Para isso, foram considerados experimentos iniciados com a hibridação direcionada para obtenção de progênies no ano de 2004, a avaliação de testes de progênies em condições experimentais no período de 2005 a 2012, e avaliações em diferentes ambientes da Amazônia Ocidental no período de 2012 a 2018. De uma população composta por 288 indivíduos estruturados em nove progênies de irmãos completos foram selecionados 12 genótipos com amplitude de 127,70 a -19,19% em suas estimativas de ganho com a seleção, para serem avaliados em quatro ambientes da Amazônia Ocidental. O ambiente que apresentou maior correlação entre os valores genéticos preditos e o ganho realizado foi Ouro Preto do Oeste - RO (0,67), local em que as plantas foram selecionadas, seguido pelos ambientes de Alta Floresta D´Oeste - RO (0,44), Rio Branco - AC (0,43) e Porto Velho - RO (0,37). Avaliações em condições experimentais mostraram que os efeitos devido aos desvios de dominância foram aproximadamente três vezes maiores do que os efeitos aditivos. Nove clones apresentaram maiores estimativas de ganho em condições experimentais e nos ensaios de campo, e dois clones apresentaram menores estimativas em ambas condições. O clone G17-P7 apresentou altas estimativas de ganho em condições experimentais e baixo desempenho em campo. A seleção em único ambiente esteve positivamente correlacionada com o desempenho dos cafeeiros em campo (r=0,55), permitindo reduzir a população de melhoramento original em um conjunto de clones de maior potencial agronômico.

Frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes in Argentina / Frecuencia y distribución geográfica de genotipos y tipos sexuales de los complejos de especies Cryptococcus neoformans y Cryptococcus gattii en Argentina

Abstract The aim of this work was to know the frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes isolated from human infections in Argentina during the period from April 2009 to April 2011. A multicenter study was conducted, in which 372 isolates were obtained from 61 laboratories throughout the country. Of those, 98.8% of the isolates belonged to the C. neoformans species complex and 1.1% to the C. gattii species complex. Genotype VNI (MATa) was the most frequently isolated (n = 326, 87.6%), followed by VNII (MATa) (n = 22, 5.9%), the recently described VNII-VNIV (aADa) hybrid (n = 14, 3.8%), VNIV (MATa) (n=4, 1.1%), VNIII (aADa) hybrid (n = 1, 0.3%), and VNIII (aADa) hybrid (n = 1, 0.3%). The Argentine Central region showed the greatest number of cases and genotype diversity. Interestingly, a relative high frequency was observed in genotype VNII (MATa) in the Cuyo, Northeast and Northwest regions and, also in VNII-VNIV (aADa) hybrids in the Northwest region. C. gattii species complex was isolated at a low rate; 3 VGI (MATa) and 1 VGII (MATa) isolates were obtained from the Northwest and Central regions. In conclusion, this study shows that genotype frequencies seem to vary among regions in Argentina and reveals a relatively high frequency of rare hybrids in the Northwest region. Further regional clinical and environmental studies may help to elucidate if those varia-tions in frequencies are associated with the existence of regional ecological niches or any other regional factors.

Resumen El objetivo de! trabajo fue conocer la frecuencia y la distribución geográfica de genotipos y tipos sexuales de aislados pertenecientes a los complejos de especies Cryptococcus neoformansy Cryptococcus gattii obtenidos de infecciones humanas en Argentina. Entre abril de 2009 y abril de 2011 se realizó un estudio multicéntrico del que se obtuvieron 372 aislados de 61 laboratorios de diferentes zonas del país. El 98,8% de los aislados pertenecieron al complejo C. neoformansy el 1,1% al complejo C. gattii. El genotipo VNI (MATa) fue el más frecuente (n = 326; 87,6%), le siguieron VNII (MATa) (n = 22; 5,9%), el híbrido VNII-VNIV (aADa) (n = 14; 3,8%), VNIV (MATa) (n =4; 1,1%) y los híbridos VNIII (aADa) (n = 1; 0,3%) y VNIII (aADa) (n = 1; 0,3%). La región Centro mostró el mayor número de casos y la mayor diversidad de genotipos. Cabe destacar que el genotipo VNII (MATa) tuvo una frecuencia relativamente alta en las regiones de Cuyo, Noreste y Noroeste. En esta última región, también fue alta la frecuencia del híbrido VNII-VNIV (aADa). La frecuencia de aislamiento de miembros del complejo C. gattii fue baja: se obtuvieron 3 aislados VGI (MATa) y 1 VGII (MATa) de las regiones Centro y Noroeste. En conclusión, este estudio muestra que las frecuencias de genotipos varían entre las distintas regiones de Argentina y señala la presencia de híbridos poco comunes en una frecuencia relativamente alta dentro de la región Noroeste. Contar con mayor número de estudios clínicos y ambientales regionales podría ayudar a elucidar si tales variaciones están asociadas a la existencia de nichos ecológicos particulares o a algún otro factor regional.

Cytotoxicity activity of geldanamycin derivatives against various cancer cell lines

Geldanamycin (1) was isolated as a major compound from Streptomyces zerumbet W14. It was then used as a precursor tosynthesize two new geldanamycins: 17-(tryptamine)-17-demethoxygeldanamycin (2) and 17-(5′-methoxytryptamine)-17-demethoxygeldanamycin (3). The cytotoxicity activity of these two new compounds was evaluated and comparedwith the cytotoxicity of compound 1. Cytotoxicity activity was evaluated against a normal cell line, and three cancercell lines using an 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colorimetric assay. Thesolubility of these compounds was also determined. The solubility of compounds 2 and 3 in water was 290.69and 348.18 µM, higher than that of compound 1 by about 1.91 and 2.29 times, respectively. Compounds 2 and 3showed moderate cytotoxic activity on Vero and human cervical carcinoma cells with IC50 values of >200.00 µg/ml. The strongest cytotoxicity of compound 3 was observed in human breast carcinoma cells (MCF-7) and humanhepatocellular carcinoma cell line (HepG2) cells with IC50 values of 82.50 and 114.35 µg/ml, respectively, while theIC50 values of compound 2 against MCF-7 and HepG2 cells were 105.62 and 124.57 µg/ml, respectively. The findingsshowed that these new geldanamycin derivatives exhibited selective cytotoxicity toward some cancer cells at a lowerconcentration. Therefore, future studies on these compounds could be useful for the management of some cancers

Antiviral activity of geldanamycin and its derivatives against influenza virus

Two new geldanamycin derivatives such as 17-(tryptamine)-17-demethoxygeldanamycin (2) andC17 methoxyl of geldanamycin (1). Their antiviral activity was evaluated based on influenza virus propagation inembryonated chicken eggs and viral absorption by hemagglutination (HA) inhibition test. The findings indicatedthat these compounds inhibited viral propagation at a concentration of 12.5 µg/ml. For the viral absorption, onlycompounds 2 and 3 inhibited HA at a concentration of 50 µg/ml. The solubility of compounds 2 and 3 in waterwas 290 and 306 µM, higher than that of compound 1 about 1.91 and 2.01 times, respectively. The compounds 2and 3 showed a moderate cytotoxic activity on LLC-MK2 and Vero cells with IC50 values of >200.00 µg/ml. Theseresults demonstrated the invention of tryptamine-geldanamycin hybrids to prevent influenza virus infection in viralabsorption and viral propagation steps.

Design, synthesis, and biological evaluation of ligustrazine/resveratrol hybrids as potential anti-ischemic stroke agents / 中国天然药物

To search for potent anti-ischemic stroke agents, a series of tetramethylpyrazine (TMP)/resveratrol (RES) hybrids 6a-t were designed and synthesized. These hybrids inhibited adenosine diphosphate (ADP)- or arachidonic acid (AA)-induced platelet aggregation, among them, 6d, 6g-i, 6o and 6q were more active than TMP. The most active compound 6h exhibited more potent anti-platelet aggregation activity than TMP, RES, as well as positive control ticlopidine (Ticlid) and aspirin (ASP). Furthermore, 6h exerted strong antioxidative activity in a dose-dependent manner in rat pheochromocytoma PC12 cells which were treated with hydrogen peroxide (HO) or hydroxyl radical (·OH). Importantly, 6h significantly protected primary neuronal cells suffered from oxygen-glucose deprivation/reoxygenation (OGD/R) injury, comparable to an anti-ischemic drug edaravone (Eda). Together, our findings suggest that 6h may be a promising candidate warranting further investigation for the intervention of ischemic stroke.

Guacamayos en peligro de extinción criados por híbridos / Macaws in Danger of Extinction Reared by Hybrids / Araras ameaçadas de extinção criadas por híbridos

Resumen La intervención humana es generalmente responsable de la creación de psitácidos híbridos en cautiverio. Este es el núcleo de la controversia del presente artículo. Con y sin intención se generan híbridos en los centros de fauna, que se suman a aquellos ingresados por entregas voluntarias de sus tenedores o como resultado del tráfico ilegal de especies. Esto conduce a la existencia de aves, sin una finalidad concreta, en refugios dedicados a la conservación. Este trabajo tiene como objetivo relatar la cría de guacamayos en peligro de extinción como herramienta para la conservación, usando guacamayos híbridos a manera de padres sustitutos, dentro del plan de manejo del Centro de rescate, rehabilitación y reubicación de fauna, "La Esmeralda", Argentina. Las hembras híbridas colocaron huevos estériles, los cuales fueron reemplazados por huevos de otras especies puras de guacamayos como Ara glaucogularis, A. rubrogenys, A. severus del programa 2015. Dichos padres híbridos incubaron, cuidaron excelentemente de las crías y enseñaron todas las herramientas necesarias para el normal desenvolvimiento de estas tanto dentro como fuera del nido, con lo cual se superó a la cría artificial, ya que eliminó la impronta humana y paralelamente a ello, el retiro de huevos a los padres originales hizo que los mismos tuvieran hasta dos posturas más por temporada. Dichos reportes no solo son relevantes para destacar a la cría diferida con híbridos, sino que valoriza a las aves híbridas en los centros faunísticos.

Abstract Human intervention is usually responsible for the creation of hybrid Psittacidae in captivity. This is the core of the controversy addressed in this article. Either intentionally or not, humans create hybrids in the fauna centers and then are mixed with those specimens brought voluntarily by their hosts or as a result from the unlawful animal traffic. This has resulted in the existence of birds in preservation sanctuaries without any concrete purpose. This work aims to report the breeding of macaws in danger of extinction as a tool for their preservation, by using hybrid macaws as substitute prents under a management plan at the Center "La Esmeralda" for rescue, rehabilitatio and relocation of fauna in Argentina. Female hybrids laid sterile eggs that were replaced with eggs from other pure macaw species like Ara glaucogularis, A. rubrogenys, and A. severus in the 2015 program. Hybrid parents incubated and raised optimally the offspring and taught them all the tools required for their normal life both inside and outside the nest. This way, the artificial breeding was overcome and the human intervention was removed. At the same time, taking the eggs from the original parents led them to laid eggs up two more times in the same season. These reports are relevant not only to promote the hybrid parent-based breeding but also to appreciate the hybrid birds in the fauna centers.

Resumo A intervenção humana geralmente é responsável pela criação de psitácideos híbridos em cativeiro. Esse o cerne da controvérsia deste artigo. Com e sem intenção os híbridos são gerados em centros de fauna e adicionados aos admitidos por entregas voluntárias de seus detentores ou como resultado do tráfico ilegal de espécies. Isso leva à existência de aves, sim finalidade concreta, em refúgios dedicados a conservação. Este trabalho tem por objetivo mostrar a cria de araras ameaçadas de extinção como ferramenta para a conservação, usando araras híbridas a maneira de pais substitutos, dentro do plano de manejo do Centro de resgate, reabilitação e relocalização de animais selvagens, "La Esmeralda", Argentina. As fêmeas híbridas depositaram ovos estéreis, que foram substituídos por ovos de outras espécies puras de araras como Ara glaucogularis, A. rubrogenys, A. severus do programa 2015. Tais pais híbridos incubaram, cuidaram muito bem da prole e ensinaram todas as ferramentas precisas para o normal desenvolvimento dentro e fora do ninho, com o que foi superada a cria artificial, toda vez que eliminou a pegada humana e paralelamente a isso, a remoção de ovos dos pais originais fazia com que tivessem até duas posturas mais por temporada. Tais relatórios não são apenas relevantes para destacar a criação diferida com híbridos, mas também valoriza as aves híbridas nos centros faunísticos.

The Effect of High Temperature on the Growth Performance of Hybrid Tilapia Oreochromis niloticus X Oreochromis aureus Juveniles Reared in a Recycling System

Tilapia juveniles live in littoral regions of freshwater ecosystems which have temperatures that may reach critical values for growth, especially in face of the onslaught of climate change. This study analyzes the effect of temperature (25, 30, 35, 40°C) on the growth and survival of hybrid tilapia juveniles in a re-circulating system. Duplicate groups of 30 juveniles were stocked in 200 L tanks in a closed, re-circulating system. Automatic heaters were used to establish the water temperatures, commercial food was supplied at 5% of their weight as daily ration. Fish were weighed and measured at 15-day intervals for a period of 3 months. Water temperature and dissolved oxygen were monitored daily. Ammonia, nitrates and dissolved reactive phosphorus were monitored every third day. Fish responses were estimated through variations in length, weight and inter-circuli space of fish scales. Average initial and final weight and length, Specific growth rate (SGR), Fulton Index (FI), Length-weight relationship and survival were used to assess tilapia growth performance. Weight, length, SGR and FI were significantly affected (P < 0.05) by water temperature. Growth of the fish reared at 30oC was almost one third greater than that at 25°C and one sixth greater than that at 35°C. Except for fish reared at 40°C, the other treatments showed a positive allometric growth, with the better results recorded for the 30 and 35°C treatments. The fish reared at 40°C survived only two weeks while the survival rate of 98, 90 and 88.3% for 25, 30 and 35°C, respectively.

Tolerance to hydric stress on cultivars of silicon-fertilized corn crops: absorption and water-use efficiency / Tolerância ao estresse hídrico em cultivares de milho adubadas com silício: absorção e eficência no uso da água

Silicon (Si) plays specific functions in agriculture. Si is a beneficial element, as it accumulates at high amounts in plant tissue. Si accumulation in cell walls reduces water loss by transpiration and may be an adaptation factor to water stress. This study evaluated the efficiency of different corn crops using calcium silicate as a reducer of hydric stress. The experiment was organized in a factorial scheme, completely randomized, with two doses of calcium silicate (0 and 100 % according to soil liming) with two irrigation depths: (30 and 100 % of necessary water reposition in the soil) and two corn cultivars: (cv. BRS-1010) considered sensitive to hydric stress and (cv. DKB-390) tolerant to hydric stress. The study comprised four repetitions. We studied dry matter production on leaves and stem, weight of 1000 seeds and crop yield. We measured efficiency of gas exchange and water use to compare the different treatments. The results for stem and leaves dry matter were better in both cultivars when using calcium silicate, regardless of irrigation depth. Both corn cultivars cv. BRS-1010, sensitive to hydric stress, and cv. DKB-390, tolerant to hydric stress, had greater yield in the presence of calcium silicate, when at the smallest irrigation dose was applied. The treatment with calcium silicate was the most efficient in water use, using 30% of irrigation depth. Cv. DKB 390 was the most productive, with greater tolerance to water stress.

O silício (Si) desempenha funções específicas na agricultura, sendo considerado um elemento benéfico, pois se acumula em quantidades elevadas no tecido da planta. O acúmulo de Si nas paredes celulares reduz a perda de água pela transpiração e pode ser um fator de adaptação ao estresse hídrico. Este estudo avaliou a eficiência de diferentes cultivares de milho utilizando o silicato de cálcio como amenizador do estresse hídrico. O experimento foi organizado em esquema fatorial, inteiramente casualizado, com duas doses de silicato de cálcio (0 e 100% de acordo com a calagem do solo), com duas lâminas de irrigação (30 e 100% de reposição de água necessária no solo) e duas cultivares de milho: a (cv. BRS-1010) considerada sensível ao estresse hídrico e a (cv. DKB-390) tolerante ao estresse hídrico, com quatro repetições. Estudamos a produção de matéria seca em folhas e caule, o peso de 1000 sementes e o rendimento da cultura. Medimos a eficiência das trocas gasosas e do uso da água para comparar os diferentes tratamentos. Os resultados para matéria seca do caule e das folhas foram melhores em ambas as cultivares, quando utilizadas o silicato de cálcio, independente da lâmina de irrigação. As duas cultivares de milho estudadas, cv. BRS-1010 tolerante ao estresse hídrico e o DKB-390 tolerante ao estresse hídrico apresentaram maior produção na presença de silicato de cálcio, quando a menor lâmina de água foi aplicada. A maior eficiência no uso da água foi obtida no tratamento com silicato de cálcio, utilizando 30% de irrigação. A cv. DKB 390 foi a mais produtiva, com maior tolerância ao déficit hídrico.

Cytotoxic and antibacterial polyketide-indole hybrids synthesized from indole-3-carbinol by

Two skeletally undescribed polyketide-indole hybrids (PIHs), named indolchromins A and B, were generated from indole-3-carbinol (I3C) in the fungal culture (). The indolchromin structures were elucidated mainly by their 1D and 2D NMR spectra with the former confirmed by the single-crystal X-ray crystallographic analysis. Each indolchromin alkaloid was chirally separated into four isomers, whose absolute configurations were assigned by comparing the recorded circular dichroism (CD) spectra with the electronic CD (ECD) curves computed for all optional stereoisomers. Furthermore, the indolchromin construction pathways in fungal culture were clarified through enzyme inhibition, precursor feeding experiment, and energy calculation. The cascade reactions, including decarboxylative Claisen condensation catalyzed by 8-amino-7-oxononanoate synthase (AONS), C()-H activation, double bond migration, and Michael addition, all undergone compatibly during the fungal cultivation. In an MIC range of 1.3-8.6 μmol/L, (2,4)- and (2,4)-indolchromin A and (2,4)-indolchromin B are inhibitory against , , sp., , and . (2,4)-Indolchromin A and (2,4)-indolchromin B were cytotoxic against the human breast cancer cell line MDA-MB-231 with IC values of 27.9 and 131.2 nmol/L, respectively, with the former additionally active against another human breast cancer cell line MCF-7 (IC 94.4 nmol/L).

Phenology and thermal requirements of grapevine cultivars in Dois Vizinhos, Paraná State, Brazil / Fenologia e requerimento térmico de cultivares de videiras em Dois Vizinhos, PR, Brasil

ABSTRACT: This study aimed to characterize the phenology and thermal requirements of grapevine cultivars Bordô, BRS Carmem, BRS Lorena, BRS Magna, BRS Rubea, BRS Violeta, Concord, Concord Clone 30, Isabel, Isabel Precoce, Moscato Bailey, Moscato Embrapa, Niagara Branca, Niagara Rosada, and Seibel 5455 grafted on Paulsen 1103. The study was conducted in the fruit growing sector of the Federal Technological University of Paraná, Câmpus Dois Vizinhos, Paraná State, Brazil, during the cycles of 2015/2016 and 2016/2017. The experimental design was completely randomized, with four replicates and two evaluated plants per plot. Plants were grown in a vertical trellis system and spur pruned with two buds. Evaluations of phenology and thermal requirements were carried out from pruning to harvest. Cultivars Moscato Bailey and Seibel 5455 had high thermal requirements and longer cycles, while cultivars BRS Magna, BRS Violeta, and Isabel Precoce had lower thermal requirements and shorter cycles. The cycle and the thermal requirements of cultivars ranged from 98 to 132 days, and from 1065 to 1548 degree-days, respectively.

RESUMO: Este trabalho objetivou caracterizar a fenologia e o requerimento térmico das cultivares de videiras Bordô, BRS Carmem, BRS Lorena, BRS Magna, BRS Rubea, BRS Violeta, Concord, Concord Clone 30, Isabel, Isabel Precoce, Moscato Bailey, Moscato Embrapa, Niagara Branca, Niagara Rosada e Seibel 5455, sobre o porta-enxerto Paulsen 1103. A pesquisa foi realizada no setor de fruticultura da Universidade Tecnológica Federal do Paraná, Campus de Dois Vizinhos, durante as safras 2015/2016 e 2016/2017. O delineamento experimental foi inteiramente ao acaso, com quatro repetições e duas plantas úteis por parcela. As plantas foram conduzidas em espadeira em cordão esporonado com poda curta em duas gemas. As avaliações de fenologia e exigências térmicas foram realizadas desde a poda até a colheita. As cultivares Moscato Bailey e Seibel 5455 possuem maiores requerimentos términos e ciclos mais tardios, enquanto BRS Magna, BRS Violeta e Isabel Precoce possuem menores requerimentos térmicos e ciclos mais precoces. O ciclo e o requerimento térmico das cultivares variou de 98 a 132 dias, e de 1065 a 1548 graus-dia, respectivamente.

Assessment of Culture Potentialities of Hybrids from Crosses between Oreochromis niloticus and Sarotherodon melanotheron Reared in Ebrié Lagoon (Côte d’Ivoire) Using Geometric Morphometric Approach

Culture potentialities of the hybrids from crosses between Oreochromis niloticus (Linnaeus, 1758) and Sarotherodon melanotheron (Rüppel, 1852) were assessed in breeding design through morphological features using geometric morphometric approach. The crosses and rearing procedure, that lasted six months, are performed into a concrete pond at Layo Aquaculture Station. The morphological studies were undertaken with morphometric biomarkers such as average body shape and components of developmental homeostasis (canalisation and developmental stability). Average body shape between groups was investigated using Relative Warps Analysis (RWA) and Canonical Variates Analysis (CVA), whereas canalisation and fluctuating asymmetry were evaluated from ANOVA Procrustes. The results showed that the body shape of the hybrids is intermediate between those of the two parental species and that the reciprocal hybrids of first generation exhibit heterosis in size. This hybrid vigor appeared more on the hybrids resulting from crosses between S. melanotheron males and O. niloticus females. In a general way, the morphology of the head of the hybrids is similar to that of the parent O. niloticus and their fins resembled to those of the parent S. melanotheron. Moreover, fluctuating asymmetry in shape does not vary between parental species and hybrids, contrary to fluctuating asymmetry in size, which is lesser in latter. Canalisation was found to be smaller in the hybrids compared to the parental ones. So, these results revealed that the hybrids could benefit from most of accrued advantages of parental species.

Physicochemical characterization of banana fruit by univariate and multivariate procedures / Caracterização físico-química de frutos de bananeira por procedimentos uni e multivariados

Breeding genotypes need to be characterized and evaluated in different soil and climatic conditions. There are few studies on association between characters evaluated and their contribution to banana genetic diversity, being essential to guide genetic breeding programs. This study aimed to evaluate the physicochemical characters of banana genotypes, to estimate associations between characters, to determine the relative importance of characters to study on genetic dissimilarity, and to indicate new genotypes to coastal plain region of Sergipe. Fruits from thirteen genotypes were used: Prata (FHIA-18, BRS Platina, PV94-01, BRS Garantida, YB42-47, Pacovan, and Prata Anã), Maçã (BRS Princesa, BRS Tropical, and Maçã), Ibota (Caipira), Gros Michel (Bucaneiro), and Mysore (Thap Maeo). The experimental design was randomized blocks, with thirteen genotypes and three replications. There is physicochemical variability of fruits between genotypes of same genomic group and subgroup, and between hybrids originated from same progenitor. Content of total sugars has greater contribution to genetic diversity among the genotypes, followed by fruit mass and pulp mass, and starch content in two cycles. Associations between fruit length, fruit diameter, and fruit mass and pulp mass in two production cycles based on phenotypic correlation are highly significant. Hybrids FHIA-18, PA94-01, YB42-47, and BRS Tropical, BRS Princesa, and Bucaneiro cultivars are promising for recommendation on coastal plain regions.

Genótipos melhorados necessitam ser caracterizados e avaliados em diferentes condições edafoclimáticas. Existem poucos estudos sobre a associação entre os caracteres avaliados e sua contribuição para a diversidade genética da banana, sendo imprescindíveis para orientar programas de melhoramento genético. O objetivo desse trabalho foi avaliar os caracteres físico-químicos de frutos de genótipos de bananeira, estimar as associações entre caracteres, determinar a importância relativa dos caracteres para o estudo da dissimilaridade genética e indicar novos genótipos para a região de Tabuleiros Costeiros de Sergipe. Foram utilizados frutos de treze genótipos: tipo Prata (FHIA-18, BRS Platina, PV94-01, BRS Garantida, YB42-47, Pacovan e Prata-Anã), Maçã (BRS Princesa, BRS Tropical e Maçã), Ibota (Caipira), Gros Michel (Bucaneiro) e o Mysore (Thap Maeo). O delineamento experimental foi em blocos ao acaso, com treze genótipos e três repetições. Existe variabilidade físico-química dos frutos entre os genótipos do mesmo grupo genômico e subgrupo, e entre híbridos originados da mesma genitora. O teor de açúcares totais apresenta maior contribuição para a diversidade genética entre os genótipos, seguido da massa do fruto com e sem casca e teor de amido nos dois ciclos. As associações entre comprimento do fruto, o diâmetro, massa do fruto e da polpa nos dois ciclos de produção com base na correlação fenotípica são altamente significativas. Os híbridos FHIA-18, PA94-01, YB42-47 e as cultivares BRS Tropical, BRS Princesa e Bucaneiro são promissores para recomendação nos Tabuleiros Costeiros.

Characterization of processing tomato lines as the physiological and production characteristics / Caracterização de linhagens de tomateiro industrial quanto à características fisiológicas e de produção

The tomato crop has social, food, and economic importance both in Brazil and internationally for generating high employment opportunities in the productive sector and offering high nutritional value of the fruits. Given the importance of this tomato culture, there is a constant search for improved varieties that meet the needs of producers in the processing industry. The objective of this study was to characterize strains of the industrial tomato in the absorption of macronutrients and micronutrients, in level of chlorophyll content in leaves, in productivity, and in uniformity of maturation fruits. The experiment was conducted in 2014 in the experimental area of the Federal University of Goiás in Goiânia. The design was a randomized block with 25 treatments (22 lines and three commercial hybrids) and four replications. We evaluated the chlorophyll content in leaves, macronutrient content, foliar macro and micronutrient content, fruit yield, and uniformity of maturation. The lineages CVR 1, CVR 3, CVR4, CVR 5, CVR21, and CVR 22 have high productivity, as well as being uniform in maturation. The lineages CVR 2, CVR 5, CVR 7, CVR 8, CVR 9, CVR 10, CVR 11, CVR 12, CVR 13, CVR 14, CVR 15, CVR 16, CVR 17, CVR 18, CVR 19 and CVR 20 are uniform in maturation. The lines have different potentials regarding the absorption of P, K, Ca, Mg and Zn. There is a positive correlation between the chlorophyll content and the amount of nitrogen present in the leaves.

A cultura do tomateiro possui importância social, alimentar e econômica tanto no cenário brasileiro quanto no internacional pela alta empregabilidade do setor produtivo e alto valor nutritivo dos frutos. Diante da relevância da cultura, é constante a busca por cultivares melhoradas que atendam as necessidades dos produtores, bem como das indústrias de processamento. Objetivou-se com este trabalho caracterizar linhagens de tomateiro industrial quanto à absorção de macronutrientes e micronutrientes, teor de clorofila, produtividade e uniformidade de maturação. O experimento foi conduzido no ano de 2014, em área experimental da Universidade Federal de Goiás, em Goiânia. O delineamento foi em blocos casualizados com 25 tratamentos (22 linhagens e três híbridos comerciais) e quatro repetições. Foram avaliados o teor de clorofila presente nas folhas, teores de macro e micronutrientes foliares, produtividade de frutos e a uniformidade de maturação. As linhagens CVR 1, CVR 3, CVR 4, CVR 5, CVR 21 e CVR 22 apresentam alta produtividade, além de serem uniformes quanto a maturação. As linhagens CVR 2, CVR 5, CVR 7, CVR 8, CVR 9, CVR 10, CVR 11, CVR 12, CVR 13, CVR 14, CVR 15, CVR 16, CVR 17, CVR 18, CVR 19 e CVR 20 são uniformes na maturação. As linhagens têm potenciais diferentes quanto à absorção de P, K, Ca, Mg e Zn. Há uma correlação positiva entre o teor de clorofila e a quantidade de nitrogênio presente nas folhas.

Distribution of the members of the Pipiens Assemblage in the sympatric area from Argentina: which is where and when?

Given their medical and veterinary relevance, the members of the Pipiens Assemblage are a worldwide target of ecological research. The distribution of Culex pipiens s.s. and Cx. quinquefasciatus converge in Buenos Aires, Argentina, where hybrids have been detected. Each member of the assemblage exhibits a distinct eco-physiological behaviour that can affect its efficiency in pathogen transmission. Our aim was to identify the environmental drivers for the spatio-temporal distribution of each member, focusing on latitudinal and urbanisation gradients. Immatures of mosquitoes were surveyed in artificial containers found within 11 public cemeteries, raised up to the adult stage and identified by their male genitalia. The distribution of each member was associated with the environment in a Generalized Linear Model. The variable accounting for most of the heterogeneity was latitude; Cx. quinquefasciatus was collected more frequently at northern cemeteries, whereas Cx. pipiens and hybrids were more likely at the southern extreme. The urbanisation gradient was also associated with the occurrence of Cx. quinquefasciatus and hybrids at the high and low end, respectively. Other relevant variables were cemetery total area, the proportion with graves and the presence of plastic flowers in the containers. The spatial distribution of the members of the Pipiens Assemblage within the sympatric region in South America is driven by environmental features. The information presented herein provides essential baseline data for surveillance programs and control activities.