REFERÊNCIAS BIBLIOGRÁFICAS

REFERÊNCIAS BIBLIOGRÁFICA

Competitive ability of canola hybrids resistant and susceptible to herbicides.

ABSTRACT - This work aimed to compare the competitive ability of canola hybrids susceptible (conventional) or resistant to triazine or imidazolinone group herbicides, with turnip. The experiments were conducted in greenhouse, in a completely randomized design, with four replicates. The hybrids Hyola 571CL (resistant to imidazolinone), Hyola 555TT (resistant to triazine), and Hyola 61 (conventional) were used. The treatments consisted of ratios (100:0; 75:25; 50:50; 25:75; 0:100%) of canola and turnip plants. The evaluation was performed 44 days after emergence, determining the leaf área (AF), dry matter of aerial part (MSPA), and stature (EST) of the plants. The competitiveness analysis was performed through diagrams and interpretation of the competitiveness indexes. For the canola hybrids, the competition occurred by the same mean resources. There was damage to the crop growth in competition with the turnip. The turnip was not benefited only when in competition with Hyola 571CL hybrid, for the EST variable, and with the conventional canola, for the variable AF. There was significance for the competitiveness indexes, demonstrating that turnip is more competitive then the crop. Greater AF, MSPA, and EST occurred for canola plants in the smallest proportions of turnip and, for turnip plants, in the largest proportions of canola. The ability to compete with turnip is similar among hybrids, with injury to the crop and benefit to the weed, when competing. Interspecific competition is more damaging to canola hybrids; and intraspecific competition is more damaging to turnip. Keywords: Brassica napus L., Raphanus sativus L., interference, competitiveness. RESUMO - Este trabalho objetivou comparar a habilidade competitiva de híbridos de canola, suscetível (convencional) ou com resistência aos herbicidas do grupo das triazinas ou das imidazolinonas, com o nabo. Os experimentos foram conduzidos em casa de vegetação, no delineamento inteiramente casualizado com quatro repetições. Foram utilizados os híbridos Hyola 571CL (resistente a imidazolinonas), Hyola 555TT (resistente a triazinas) e Hyola 61 (convencional). Os tratamentos consistiram de proporções (100:0; 75:25; 50:50; 25:75; 0:100%) de plantas de canola e do nabo. A avaliação foi realizada aos 44 dias após a emergência, determinando-se a área foliar (AF), matéria seca de parte aérea (MSPA) e estatura (EST) de plantas. A análise da competitividade foi feita por meio de diagramas e interpretação dos índices de competitividade. Para os híbridos de canola, a competição ocorreu pelos mesmos recursos do meio. Houve prejuízo ao crescimento da cultura em competição com o nabo. O nabo somente não foi beneficiado quando em competição com o híbrido Hyola 571CL, para a variável EST, e com a canola convencional, para a variável AF. Houve significância para os índices de competitividade, demonstrando que o nabo é mais competitivo que a cultura. Maior AF, MSPA e EST ocorreu para plantas de canola nas menores proporções de nabo e, para plantas de nabo, nas maiores proporções de canola. A habilidade em competir com o nabo é semelhante entre os híbridos, havendo prejuízo à cultura e benefício à planta daninha, quando em competição. A competição interespecífica é mais prejudicial para os híbridos de canola, e a competição intraespecífica, para o nabo. Palavras-chave: Brassica napus L., Raphanus sativus L., interferência, competitividade

Gene expression related to oxidative stress induced by herbicides in rice.

Herbicides are stressors that can have negative effects on plants. In Oryza sativa (L.), differential gene expression may be evalu-ated through real-time reverse transcription quantitative poly-merase chain reaction (RT-qPCR). The aim of this study was to evaluate the stability of candidate reference genes and to quan-tify the relative expression of oxidative stress genes at different times (12, 24, 48, and 96 hours after treatment [HAT]) with penoxsulam, cyhalofop-butyl, and bentazon herbicides. Norm-Finder, BestKeeper, and GeNorm software and the compara-tive ∆Ct method were used to assess expression stability and to determine the RT-qPCR threshold values of the candidate reference genes. The UBQ5 gene was the most stable among the reference genes analyzed. The gene expression results showed upregulation of OsCAT and OsMnSOD1 genes at all times after herbicide application. The OsA PX 2 and OsGST3 genes showed increased gene expression at 12 and 96 HAT for all herbicides. The OsHO -1 gene had the most significant expression changes, with maximum expression levels at 24 HAT with bentazon and at 96 HAT with penoxsulam and cyhalofop-butyl. Overall, antioxidant system gene expression increased after the applica-tion of bentazon, penoxsulam, and cyhalofop-butyl in ric

Propriedades físicas e mecânicas de compósitos de cimento reforçados com fibra de curauá (Ananas erectifolius)

O objetivo deste estudo é a caracterização de compósitos cimentícios com reforço de fibras longas de curauá. Estes compósitos são constituídos de matriz cimentícia composta por cimento CP V-ARI, areia, água e superplastificante. A substituição de materiais como o cimento por reforços de materiais naturais como a fibra de curauá se tornam objetos de pesquisa por reduzirem o custo, serem biodegradáveis, gerarem baixa energia em sua produção e possuírem propriedades como baixa densidade e capacidade de isolamento térmico e acústico. Para a produção dos compósitos laminados, foi determinada a influência da fração volumétrica de fibras no compósito em teores de adição de 0%, 5%, 10%, 15% e 20%. Como metodologia moldou-se o compósito em cinco camadas, intercalando três camadas de matriz cimentícia e duas camadas de reforço de fibra de curauá. Os ensaios avaliaram o comportamento físico e mecânico dos compósitos em diferentes dias (7, 28 e 90 dias). Observou-se que o teor de fibra de curauá de 10%, com essa metodologia, apresentou resultados compatíveis à referência com relação à resistência à flexão aos 90 dias, sendo indicado dessa forma a cura dos painéis por 90 dias para aplicação. E a redução na massa específica dos painéis foi possível, de forma significativa, com as adições acima de 10% de fibra de curauá.The objective of this study is the characterization of cementitious composites with reinforcement of long fibers of curauá. These composites consist of a cement matrix composed of CP V-ARI cement, sand, water and superplasticizer. The replacement of materials such as cement with reinforcements of natural materials such as curauá fiber become objects of research because they reduce the cost, are biodegradable, generate low energy in their production and have properties such as low density and thermal and acoustic isolation capacity. For the production of laminated composites, the influence of the volumetric fraction of fibers in the composite was determined at addition levels of 0%, 5%, 10%, 15% and 20%. As a methodology, the composite was molded in five layers, interspersing three layers of cement matrix and two layers of curauá fiber reinforcement. The tests evaluated the physical and mechanical behavior of the composites on different days (7, 28 and 90 days). It was observed that the curauá fiber content of 10%, with this methodology, presented results compatible with the reference in relation to the flexural strength at 90 days, thus indicating the curing of the panels for 90 days for application. And the reduction in the specific mass of the panels was possible, in a significant way, with the additions above 10% of curauá fiber

Pre-harvest herbicide application reduces the Italian ryegrass seed viability.

Italian ryegrass (Lolium multiflorum Lam.) is a troublesome weed found in temperate agricultural fields, wherein the future infestations depend on the soil seed bank. The aim of this research was to evaluate Italian ryegrass seed viability subjected to herbicide application in different phenological stages of development. Experiments were carried out in a completely randomized experimental design with four repetitions. Paraquat, ammonium-glufosinate, iodosulfuron-methyl and clethodim herbicides were applied in three development stages (pre-spike, anthesis, and grain filling) and compared to the control. The effects were evaluated by percentage of control at seven, 14, and 28 days after application (DAA), seeds per plant, 1000 seeds weight, and percentage of germination, abnormal seedlings, dead seeds, viable and non-viable dormant seeds. Control was greater than 97% at 28 DAA, with a decrease of more 90% for seed per plant, and strong reduction of 1000 seeds weight for the herbicides applied up to the anthesis stage. At the grain filling stage, clethodim reduced seed production by 18% and 1000-seeds weight by 36% compared to the control. Ammonium-glufosinate and paraquat herbicides applied up to the anthesis stage reduced seed viability by more than 98%. Overall, herbicide application reduces seed production, seed weight and viability, especially when applied before the grain filling stage. Highlighted Conclusions 1. Herbicide application up to the anthesis developmental stages reduces seed production, 1000 seeds weight, and seed viability. 2. Paraquat was the best herbicide to reduce seed production per plant, 1000-seeds weight and, viability of Italian ryegrass seeds, regardless of development stages. 3. Reducing future infestations of Italian ryegrass in cropping systems depends on herbicide application before the grain filling

May the crossing between diploid and tetraploid Italian ryegrass transfer glyphosate resistance to the next generation?

Italian ryegrass (Lolium multiflorum Lam.) is a grass weed found in winter cereals, with several glyphosate-resistant diploid populations. Furthermore, the use of Italian ryegrass tetraploid genotypes creates an opportunity to increase the forage demand in replacement of diploid populations. The aim of this research was to evaluate the crossing capacity between glyphosate-resistant diploid and tetraploid Italian ryegrass to transfer glyphosate resistance to the next generation. Reciprocal crosses were performed using the susceptible tetraploid cultivar INIA Titan and resistant diploid (SVA04 biotype) plants to obtain the F1 progeny. Germination testing, survival percentage, inheritance of glyphosate-resistance, and ploidy level were evaluated in F1 progeny. Crossing of susceptible tetraploid plants ♂ and glyphosate-resistant diploid ♀ affected the germination and exhibited 4.5% of triploid plants. F1 progeny from the glyphosate-resistant diploid ♂ and susceptible tetraploid ♀ did not show germination problems, but 46% of the plants died during the initial seedling stage. For this progeny, 10 and 25% of the seedlings were composed of triploid and pentaploid individuals, respectively. Crosses between susceptible tetraploid ♀ and resistant diploid ♂ did not transfer the glyphosate-resistant for the plants. Susceptible tetraploid ♂ crossing with diploid resistant ♀ had a reduction of 47% the glyphosate-resistant plants compared to the homozygous glyphosate-resistant progeny. Overall, tetraploid Italian ryegrass can be a safe tool to reduce and manage the increase of glyphosate-resistant diploid ryegrass in field conditions. Key words: Lolium multiflorum Lam., ploidy level, chromosome counting, resistance

Rules extraction from neural networks applied to the prediction and recognition of prokaryotic promoters

Promoters are DNA sequences located upstream of the gene region and play a central role in gene expression. Computational techniques show good accuracy in gene prediction but are less successful in predicting promoters, primarily because of the high number of false positives that reflect characteristics of the promoter sequences. Many machine learning methods have been used to address this issue. Neural Networks (NN) have been successfully used in this field because of their ability to recognize imprecise and incomplete patterns characteristic of promoter sequences. In this paper, NN was used to predict and recognize promoter sequences in two data sets: (i) one based on nucleotide sequence information and (ii) another based on stability sequence information. The accuracy was approximately 80% for simulation (i) and 68% for simulation (ii). In the rules extracted, biological consensus motifs were important parts of the NN learning process in both simulations

DOENÇAS DIAGNOSTICADAS PELO LABORATÓRIO DE PATOLOGIA VETERINÁRIA EM 2016

Este trabalho apresenta a casuística de diagnósticos no ano de 2016 do Laboratório de Patologia Veterinária do IFC Campus Concórdia. Foram 236 diagnósticos em bovinos, 31 em ovinos e 125 em suínos, totalizando 392. Destes, 268 (68,4%) foram através de necropsias e 124 (31,6%) através de amostras formolizadas enviadas por veterinários. Em bovinos as doenças mais incidentes foram miosite clostridial com 16 casos (6,8%); leucose enzoótica bovina com 9 casos (3,8%); salmonelose com 8 casos (3,4%); intoxicação por nitrato/nitrito com 8 casos (3,4%); hemoncose com 7 casos (3,1%) e anaplasmose com 6 casos (2,6%). Já em ovinos foi hemoncose com 6 casos (19,4%) e em suínos doença de Glässer com 8 casos (6,4%); circovirose com 6 casos (4,8%) e raquitismo com 6 casos (4,8%).

INTOXICAÇÃO POR NITRATO/NITRITO NO OESTE DE SANTA CATARINA - ESTUDO RETROSPECTIVO (2013-2017)

A intoxicação por nitrato/nitrito é uma enfermidade comum no estado de Santa Catarina, e que leva a morte súbita em bovinos. Trata-se de um distúrbio ocasionado pela utilização excessiva de adubação nitrogenada nas pastagens e condições climáticas adversas, como diminuição de luminosidade ou déficit hídrico, levando ao acúmulo de nitrato na pastagem. Este trabalho teve como objetivo relatar a ocorrência dos casos de intoxicação por nitrato/nitrito em bovinos na região oeste de Santa Catarina, diagnosticados pelo Laboratório de Patologia Veterinária (LPV) do Instituto Federal Catarinense – Campus Concórdia. Entre os anos de 2013 e 2017, foram diagnosticados por necropsia 10 surtos de intoxicações por nitrato/nitrito. De um total de 641 bovinos necropsiados pelo LPV nesse período, 19 correspondem a essa intoxicação, representando 2,96% da casuística de necropsias e 2,20% da casuística total de diagnósticos (necropsias e histopatológico). Ainda que seja um número expressivo de causa mortis, acredita-se que existam muitos outros casos não diagnosticados pelo LPV, visto que nem todos os animais são remetidos para necropsia. Conclui-se que as intoxicações por nitrato/nitrito são expressiva causa de morte nos rebanhos bovinos da região, devendo serem adotadas medidas de controle e prevenção. Palavras-chave: metemoglobina, patologia, bovino, diagnóstico, necropsia.