81 research outputs found

    Phenotypic, additive genetic and environment correlations of maize landraces populations in family farm systems

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    Knowledge of the association between characters is very important in the genetic breeding programs, but there is limited information about correlations between traits in maize landraces in the current literature. The objectives of this study were to estimate phenotypic, additive genetic and environment correlations among traits in maize landraces, which were cultivated in family farm systems, in order to guide the participatory breeding on maize landraces. Between 294 and 400 half-sib progenies from the six populations were evaluated, subdivided in triple 7X7 and 10X10 lattice design, respectively, with single row plots of 4 m long and spaced 1.00 × 0.20 m. Estimates of correlation coefficients are reported for nine traits: grain yield (GY), relation grain weight per ear weight (GE), ears per plant (EP), days to flower (DF), plant height (PH), ear height (EH), percentage of root loding (%L), percentage of stalk loding (%BS) and percentage of damaged ears (%DE). A high number of additive genetic correlation (rA) was obtained between grain yield and the other traits, in maize landraces populations, cycles and locations. For grain yield, the highest averages of the rA estimate were with EP (0.67), GE (0.47) and %DE (-0.63). In contrast to the current published researches, negative correlations between grain yield and days to flower were observed.O conhecimento da associação entre caracteres é de grande importância nos programas de melhoramento genético, contudo a literatura apresenta limitadas informações sobre correlações em populações de milho crioulo. Os objetivos deste estudo foram estimar correlações fenotípicas, genéticas aditivas e ambientais entre caracteres de populações de milho crioulo, cultivados em sistemas de agricultura familiar, para orientar o programa de melhoramento genético participativo. Entre 294 e 400 de progênies de meios-irmãos de seis populações, foram avaliadas em látices triplos 7X7 e 10X10, respectivamente, com parcelas de 4 m de comprimento e espaçadas 1,00 × 0,20 m. Os coeficientes de correlações foram estimados para nove características: produtividade de grãos total (GY), relação peso de grãos por peso de espiga (GE), nº de espigas por planta (EP), nº de dias do florescimento (DF), altura da planta (PH), altura espiga (EH), porcentagem de acamamento (%L), porcentagem de colmos quebrados (%BS) e porcentagem de espigas danificadas (%DE). Houve um alto número de correlação genética aditiva (rA) entre produtividade de grãos e as demais características, nas populações de milho crioulo, ciclos e locais. As maiores médias das estimativas rA para o produtividade de grãos foram com EP (0,67), GE (0,47) e DE% (-0,63). Diferentemente dos trabalhos publicados, foram observadas correlações negativas entre produtividade de grãos e dias para florescimento

    Produção de fitomassa e acúmulo de nutrientes por plantas de cobertura e cultivo da mamona em sucessão no sistema plantio direto

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    Objetivou-se avaliar a produção de matéria seca (MS) e o acúmulo de nutrientes pela crotalária (Crotalaria juncea L.) e pelo milheto (Pennisetum glaucum (L.) R. Brown), em cultivos isolado e consorciado, e o efeito do manejo mecânico da palhada no desempenho da cultura da mamona (Ricinus communis L.), em sucessão, na fase de implantação do sistema plantio direto. O experimento foi instalado em um Nitossolo Vermelho (Rhodic Kandiudox), em Botucatu, São Paulo (SP) (22°58'S, 48°23'W e 765m de altitude). O delineamento utilizado foi o de blocos casualizados, em parcelas subdivididas, com quatro repetições. As parcelas foram constituídas por três coberturas vegetais: crotalária - cultivar 'IAC-KR1'; milheto - cultivar 'BN 2'; e consórcio crotalária + milheto. As subparcelas foram constituídas pela ausência e presença do manejo mecânico da palhada com triturador horizontal 20 dias após o manejo químico. O milheto produziu maior quantidade de MS e apresentou maiores teores de K, Mg e S na parte aérea, enquanto a crotalária apresentou maiores teores de N e Ca. O milheto acumulou mais N, P, K, Mg e S na parte aérea, enquanto a crotalária acumulou maior quantidade de Ca. A produtividade de grãos da mamoneira foi maior em sucessão ao consórcio crotálaria + milheto e na ausência do manejo mecânico da palhada.The objective of this study was to evaluate aboveground matter production and nutrients accumulation by sunnhemp (Crotalaria juncea L.) and pearl millet (Pennisetum glaucum (L.) R. Brown), in sole crop and intercropped, and the effect of straw mulch mechanical management on castor bean (Ricinus communis L.) performance, in notillage system establishment. The experiment was carried out on a Rhodic Kandiudox, in Botucatu, SP, Brazil (22°58'S, 48°23'W and 765m above sea level). A randomized block design, in a splitplot scheme, with four replications, was used. The plots were composed by three cover crops: sunnhemp - cv. 'IAC-KR1'; pearl millet - cv. 'BN 2'; and intercropping - sunnhemp + pearl millet. The subplots were composed by absence or presence of straw mulch mechanical management, by horizontal crusher use, 20 days after chemical management. Pearl millet sole crop produced greater dry matter and showed higher K, Mg, and S concentration in aboveground, 75 days after emergence, while N and Ca concentration were higher in sunnhemp. Pearl millet sole crop accumulated greater amounts of N, P, K, Mg, and S, in aboveground, while sunnhemp accumulated elevated amount of Ca. Castor bean grain yield was higher in succession to sunnhemp + pearl millet intercropping and in the absence of straw mulch mechanical management

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Exposure to potentially inappropriate medications in Brazilian elderly outpatients with metabolic diseases

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    ABSTRACT Management of pharmacotherapy in elderly with metabolic diseases is challenging and potentially inappropriate medications (PIMs) are risk factors for drug interactions and adverse events. The exposure to PIMs in elderly outpatients with metabolic diseases and its relationship with polypharmacy and other variables was investigated. PIMs prescribed to 207 elderly patients (aged 60 to 96 years) with metabolic diseases who attended a University Hospital of Sao Paulo city, Brazil, from April/2010 to January/2011, were evaluated. PIMs were detected using both 2003 Beers and 2008 STOPP criteria. The association between PIMs and age, gender and polypharmacy was also examined. 2008 STOPP criteria detected more PIMs (44.4 %) than 2003 Beers criteria (16.0%, p<0.001). Beers detected mainly PIMs antihypertensive (clonidine, 20.0%; doxazosin, 10.0%) and antidepressant (fluoxetine, 15.0%; amitriptyline, 10.0%) PIMs. Medicines used for cardiovascular (aspirin, 53.7%) and endocrine system (glibenclamide, 21.3%) were PIMs more frequently detected by 2008 STOPP. Unlike age and gender, polypharmacy increased the risk of PIMs by both 2003 Beers (OR: 4.0, CI95%: 1.2-13.8, p<0.031) and 2008 STOPP (OR: 6.8, CI95%: 3.0-15.3, p<0.001). Beers and STOPP criteria are important tools to evaluate the exposure to PIMs, which is strongly associated with polypharmacy in elderly outpatients with metabolic diseases
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