خيارات البحث
النتائج 681 - 690 من 1,862
NEMATÓIDE DAS LESÕES ASSOCIADO A MUDAS DE MANGUEIRA EM ASSU-RN
2015
TORRES, GUSTAVO RUBENS DE CASTRO | SALES JÚNIOR, RUI | HOULLOU, LAUREEN MICHELLE | NEGREIROS, ANDREIA MITSA PAIVA
ABSTRACT: The aim of this study was to report for the first time Pratylenchus brachyurus population associated to mango cv. Tommy Atkins seedling roots, on naturally infested soil, on Assú municipality, Rio Grande do Norte State. The population of nematode was characterized based on a morphometric study that was done using 20 females collected from the roots. The morphometric data were compared to other data published by different authors in studies concerning to reporters of this species of root-lesion nematode, and it was possible to identify the population as P. brachyurus. | RESUMO: O objetivo do presente trabalho foi relatar, pela primeira vez, população de Pratylenchus brachyurus associada a raízes de mangueira cv. Tommy Atkins no estádio de muda em solo naturalmente infestado no município de Assú, Rio Grande do Norte. A caracterização da referida população do nematóide foi fundamentada em estudo morfométrico realizado em 20 fêmeas coletadas das raízes. Os dados morfométricos foram comparados aos dados publicados por diferentes autores em trabalhos sobre a ocorrência da referida espécie de nematóide das lesões e permitiram a identificação da população como pertencente à P. brachyurus.
اظهر المزيد [+] اقل [-]INFERÊNCIA BAYESIANA NA AVALIAÇÃO GENÉTICA DE BOVINOS DA RAÇA TABAPUÃ DO NORDESTE BRASILEIRO
2015
OLIVEIRA, ARACELE PRATES DE | MALHADO, CARLOS HENRIQUE MENDES | BARBOSA, LEANDRO TEIXEIRA | MARTINS FILHO, RAIMUNDO | CARNEIRO, PAULO LUIZ SOUZA
RESUMO: Objetivou-se comparar por meio do Fator de Bayes (FB), modelos para estimar componentes de covariância, parâmetros genéticos e valores genéticos para os pesos ajustados aos 205 (P205), 365 (P365) e 550 (P550) dias de idade em animais da raça Tabapuã, criados a pasto no Nordeste do Brasil. Foram utilizadas informações de 26.838 animais no período entre 1975 a 2007 provenientes do controle de desenvolvimento ponderal da Associação Brasileira de Criadores de Zebu (ABCZ). Os componentes de covariância e parâmetros genéticos foram estimados pela abordagem bayesiana em análises uni e bicaracterísticas utilizando-se o programa GIBBS3F90. O modelo completo proporcionou melhor ajuste para a estimativa dos parâmetros genéticos para as características P205 e P365. Quanto à característica P550, o modelo que proporcionou o melhor ajuste foi o que não incluiu o efeito de ambiente permanente. As tendências genéticas de efeito direto foram significativas para as características P205, P365 e P550, correspondendo a incrementos de 2,67 kg, 7,35 kg e 8,32 kg, respectivamente, durante os 32 anos avaliados. As tendências fenotípicas foram significativas apenas para as características P205 e P365, correspondendo a incrementos de 26,82 kg e 22,42 kg, respectivamente. As correlações genéticas entre o peso aos 205, 365 e 550 dias de idade foram de alta magnitude (P205P365=0,90; P205P550=0,90 e P365P550=0,98), podendo-se obter ganhos genéticos via resposta correlacionada para os pesos aos 365 e 550 dias de idade ao selecionar o P205. | ABSTRACT: The objective was to compare models by Bayes factor (BF) to estimate the (co)variance components, genetic parameters and genetic values for the adjusted weights at 205 (W205), 365 (W365) and 550 (W550) days of age in Tabapuã animals reared on pasture in the Brazilian Northeast. Information about 26,838 cattle born in the period from 1975 to 2007 originally from the weight-development-control system of the Brazilian Association of Zebu Farmers (Associação Brasileira de Criadores de Zebu, ABCZ) was used. The (co)variance components and genetic parameters were estimated by the Bayesian approach, in single- and two-trait analysis, using the GIBBS3F90 software. The full model provided the best fit to estimate the breeding value for W205 and W365 characteristics parameters. For trait W550, the model that provided the best fit was the one that did not include the effect of permanent environment. Genetic trends of direct effect were significant for the W205, W365 and W550 features, corresponding to increments of 2.67 kg, 7.35 kg and 8.32 kg, respectively, during the 32 years evaluated. Phenotypic trends were significant only for W205 and W365 characteristics corresponding to increments of 26.82 kg and 22.42 kg, respectively. The genetic correlations between weight at 205, 365 and 550 days of age were of high magnitude (P205P365 = 0.90, = 0.90 and P205P550 P365P550 = 0.98); you can obtain genetic gains via correlated response to the weights at 365 and 550 days old when selecting for W205.
اظهر المزيد [+] اقل [-]TAMANHO DE PARCELA E NÚMERO DE REPETIÇÕES PARA MAMONEIRA EM DIFERENTES ESPAÇAMENTOS ENTRE PLANTAS
2015
PALUDO, ANDRÉ LUIZ | LOPES, SIDINEI JOSÉ | BRUM, BETANIA | STORCK, LINDOLFO | SANTOS, DANIEL DOS | HAESBAERT, FERNANDO MACHADO
RESUMO: O planejamento adequado de experimentos na cultura de mamoneira é uma das formas de se maximizar as informações da pesquisa. Os objetivos deste trabalho foram determinar o tamanho de parcela e o número de repetições para a cultura de mamoneira e verificar a influência do espaçamento entre plantas no plano experimental. O experimento com o híbrido Sara foi conduzido na Universidade Federal de Santa Maria, em 2010, com espaçamento entre linhas de 1,2 m e espaçamentos entre plantas de 0,4, 0,6 e 0,8 m. Foram avaliados em cada planta o número de rácemos, peso de frutos, comprimento médio dos rácemos e número total de frutos, com identificação da planta pelo número de ordem da fileira e o número da planta dentro da fileira. O tamanho ótimo de parcela é de oito plantas para todos os espaçamentos e para todas as variáveis. Porém, a área do tamanho ótimo de parcela em cada espaçamento depende da área ocupada pela unidade básica. Assim, a área da parcela é de 3,84, 5,76 e 7,68 m2 para os espaçamentos entre plantas de 0,4, 0,6 e 0,8 m, respectivamente. Doze repetições, no delineamento blocos ao acaso, foram suficientes para identificar diferenças entre médias de tratamentos de 27%, com 5% de probabilidade de erro. | ABSTRACT: Proper planning of experiments in the culture of castor bean is one of the ways to maximize the research information. The aim of this study was to determine the optimum plot size and number of replications and the influence of spacing between plants in experiments involving castor bean crops. The experiment with the hybrid Sara was conducted at the Federal University of Santa Maria in 2010 with a spacing of 1.2 m between rows and between plants of 0.4, 0.6 and 0.8 m. Each plant was evaluated taking into account: the number of racemes, fruit weight, the average length of the racemes, and fruit number, with the plant identification by the order number of the row and the number of plants within the row. The optimum plot size is eight plants for all spacings and all variables. However, the area of optimum plot size inside the spacing depends on the area occupied by the basic unit. Thus, the plot area is 3.84, 5.76 and 7.68 m2 for each spacing of 0.4, 0.6 and 0.8 m, respectively. Twelve replications in randomized block design, are sufficient to identify, as significant at 5% probability, differences between treatment means of 27%.
اظهر المزيد [+] اقل [-]TAMANHO ÓTIMO DE PARCELA PARA A CULTURA DE GIRASSOL EM TRÊS ARRANJOS ESPACIAIS DE PLANTAS
2015
SANTOS, ANA MARIA PEREIRA BISPO DOS | PEIXOTO, CLOVIS PEREIRA | ALMEIDA, ADEMIR TRINDADE | SANTOS, JAMILE MARIA DA SILVA DOS | MACHADO, GISELE DA SILVA
ABSTRACT: The objective of this study was to evaluate the optimum plot size to three sunflower hybrids in three spatial arrangements of plants. The uniformity test was installed in the experimental field of the Federal University of Recôncavo of Bahia, in Cruz das Almas, Brazil, in 2012. The plots were composed of six lines of 36 m, which were willing three spatial arrangements of plants: A1 (0,45 m x 0,49 m); A2 (0,70 m x 0,32 m) and A3 (0,90 m x 0,25 m), and each arrangement were distributed three sunflower hybrids: Hélio 250, Hélio 253 e Aguara 3. For the evaluation of the optimal plot size, at 110 days after sowing was harvested a sample of 180 basic units (plants) per plot, in which were evaluated the final plant height, the final diameter of the rod and the diameter of the chapter. Thirty-one plots sizes of three hybrids were simulated and for each variable assessed, wherein each plant was considered as a basic unit. The estimation of optimum plot size to the sunflower crop was calculated by the method of modified curvature maximum. The combined use of hybrid H253, installed in the arrangement 0.45 m x 0.49 m, promotes obtainment the greatest value of curvature maximum it was estimated the optimum plot size of six plants. | RESUMO: O objetivo deste estudo foi avaliar o tamanho ótimo de parcela de três híbridos de girassol em três arranjos espaciais de plantas. O teste de uniformidade foi instalado no campo experimental da Universidade Federal do Recôncavo da Bahia, em Cruz das Almas, Brasil, em 2012. As parcelas foram compostas por seis linhas de 36 m, sendo dispostos três arranjos espaciais de plantas, quais sejam: A1 (0,45 mx 0,49 m); A2 (0,70 mx 0,32 m); e A3 (0,90 mx 0,25 m). Foram distribuidos em cada arranjo três híbridos de girassol: Hélio 250; Hélio 253; e Aguara 3. Para a avaliação do tamanho ótimo de parcela , aos 110 dias após a semeadura, foi colhida uma amostra de 180 unidades básicas (plantas) por parcela, no qual foram avaliadas a altura final de planta, o diâmetro final da haste e o diâmetro do capítulo. Foram simulados 31 tamanhos de parcela dos três híbridos e para cada variável analisada em cada planta considerada como uma unidade básica. A estimativa do tamanho de parcela para a cultura de girassol foi calculada pelo método de máxima curvatura modificada. O uso combinado do híbrido H253, instalado no arranjo de 0,45 mx 0,49 m, promoveu a obtenção do maior valor da máxima curvatura, estimando-se o tamanho ótimo de parcela de seis plantas.
اظهر المزيد [+] اقل [-]GENETIC DIVERSITY AMONG BITTER MELON GENOTYPES ASSESSED THROUGH MORPHO-AGRONOMIC VARIABLES
2022
SILVEIRA,THAÍSA DE OLIVEIRA | MARQUES,MAYARA DE MELLO | AMORIM,GUSTAVO TORRES DOS SANTOS | CARVALHO,MARIO GERALDO DE | DAMASCENO JUNIOR,PEDRO CORRÊA
ABSTRACT Bitter melon (Momordica charantia L.) is a plant species recommended by the Brazilian Health Regulatory Agency (Anvisa) as hypoglycemiant. The characterization of plants is an essential step in any breeding program. The objective of the present work was to organize and characterize a bitter melon germplasm collection, based on morpho-agronomic characters, to assess its genetic diversity and identify genotypes of agronomic interest. Eighty-eight genotypes were characterized for 38 descriptors. Redundant descriptors were identified through Principal Component Analysis (PCA); after their exclusions, a new PCA was carried out to verify the dispersion among the genotypes. Groups in the PCA were defined using the kmeans clustering method. The groups were studied for phenotype pattern using radar chart. Populational diversity was estimated through Shannon and Pielou indexes. Intra group diversity was estimated through analysis of similarity (anosim). The relative importance of variables for diversity was also estimated. Seventeen variables were redundant. The genotypes were grouped into 5 groups. Groups G1 and G5 were antagonist regarding fruit and seed productions and fruit, leaf, and seed sizes. A trend of decrease in fruit, leaf, and seed sizes was found in groups from G1 to G5. The diversity was high. Intra group diversity was high among small fruit genotypes, and low for medium-sized fruit genotypes. The variable number of male flowers (NMFL) was identified as that presented the greatest contribution to estimation of diversity. The genotypes UFRRJ MSC072, 042, 028, and 087 stood out with the highest number of fruits produced.
اظهر المزيد [+] اقل [-]LIMA BEAN POPULATIONS ASSESSMENTS VIA REML/BLUP METHODOLOGY
2022
CARVALHO,JHESSICA LANNA RODRIGUES DE | VIEIRA,MARIA DE FÁTIMA BRITO | ALBUQUERQUE,TAYNÁ MENDES DE | COSTA,GUILHERME ALEXANDRE LUZ DA | GOMES,REGINA LUCIA FERREIRA | LOPES,ÂNGELA CELIS DE ALMEIDA
ABSTRACT - Based on its nutritional and economic value, the lima bean (Phaseolus lunatus L.) is the second most important species of the genus. It has high genetic diversity and potential for production and is considered an alternative food and income source. The objective of this study was to apply the restricted maximum likelihood/ best linear unbiased prediction (REML/ BLUP) methodology to estimate genetic parameters and predict genotypic values in F3 populations of lima beans. Twelve characteristics were evaluated in five populations with indeterminate growth habits (H39, H72, H53, H90, and H56). Model 83 from the Selegen program was used for analysis. Considering the genetic parameters, the highest values of genetic variance were for plant height and number of pods per plant. Pod thickness and seed width are favorable for breeding programs. Seed width selection gain was significant for populations H56 and H90 at 11.26 mm and 10.50 mm, respectively. As for the length and thickness of seeds, the gains were less significant, with population H53 showing the greatest gain. The REML/ BLUP methodology proved efficient in estimating genetic parameters and predicting gains in lima bean populations. The estimated selection gains indicated that the highest gains were obtained for plant height, the number of pods per plant, pod thickness, seed width, and the number of days to maturity. Populations H53 and H56 stood out for having large and white seeds, thus being potential populations for species improvement.
اظهر المزيد [+] اقل [-]AGRONOMIC PERFORMANCE OF WHEAT CULTIVARS IN RESPONSE TO INOCULATION (Azospirillum brasilense) AND NITROGEN APPLICATION
2022
LUDWIG,RODRIGO LUIZ | MARTIN,THOMAS NEWTON | ROCKENBACH,DALVANE | GIACOMINI,SANDRO | VEY,ROSANA TASCHETTO
ABSTRACT The objective of this work was to verify the contribution of seed inoculation with the bacterium Azospirillum brasilense to promote growth on yield components in wheat crop. For this, experiments were carried out in different locations (Santa Maria and Cruz Alta, RS, Brazil), sowing times (June and July) and years of cultivation (2013 and 2014). A randomized block design with three replications was used. The treatments were composed by the combination of ten cultivars, three nitrogen managements and two types of inoculation (10 x 3 x 2). Inoculation was carried out with liquid inoculant in the seeds. The components of grain yield were evaluated. The average number of tillers per plant was influenced by seed inoculation (1.63 and 1.72) when uninoculated and inoculated, respectively. On the other hand, the hectoliter mass responded inversely, reducing to 75.7 kg hL-1. Inoculation with A. brasilense increased the grain mass (1%) and had no positive influence on the variables number of ears and spikelets per ear, grain yield and hectoliter weight.
اظهر المزيد [+] اقل [-]BORON AND ZINC FERTILIZER APPLICATION TO MAIZE CROPS IN A LITHIC QUARTZIPSAMMENT
2022
CRUZ,SIHÉLIO JÚLIO SILVA | COSTA JÚNIOR,JOSÉ ROBERTO DA | OLIVEIRA,SILVIA SANIELLE COSTA DE | PONCIANO,VANESSA DE FÁTIMA GRAH | VALICHESKI,ROMANO ROBERTO
ABSTRACT The objective of this work was to evaluate the effect of soil application of different boron (B) rates to the soil, with and without application of zinc (Zn), on growth, production components, and grain yield of maize crops grown in a Lithic Quartzipsamment with low B and Zn contents. A randomized block experimental design was used, in a 6×2 factorial arrangement corresponding to six B rates (0, 1, 2, 3, 4, and 5 kg ha-1), with and without application of Zn (2.0 kg ha-1), applied to the soil at sowing, with four replications. Growth variables (stem diameter and plant height), and chlorophyll SPAD index were evaluated at the R1 phenological stage. Maize ear length, one-thousand grain weight, and grain yield, and the B maximum efficiency rate were evaluated at the R6 phenological stage. Application of B and Zn to the soil increases maize grain yield in soils with sandy clay loam texture and low B and Zn contents; the plant absorption and metabolism indicated synergism between these elements when using soil applications of 1.0 kg ha-1 of B combined with 2.0 kg ha-1 of Zn to the planting furrows. The rates with maximum technical efficiency for grain yield were 3.29 and 4.31 kg of B ha-1 in treatments without and with application of Zn, respectively.
اظهر المزيد [+] اقل [-]CANONICAL CORRELATIONS BETWEEN CYCLE AND GRAIN PRODUCTION TRAITS IN LIMA BEAN1
2022
COSTA,GUILHERME ALEXANDRE LUZ DA | MEDEIROS,ARTUR MENDES | SILVA,VERÔNICA BRITO DA | LOPES,ÂNGELA CELIS DE ALMEIDA | CANDIDO,WILLAME DOS SANTOS | GOMES,REGINA LUCIA FERREIRA
ABSTRACT Lima bean is an important crop in Northeastern Brazil and a source of food and income for farmers in the region. However, there have been few genetic studies on this species, which limits the knowledge available for use in breeding programs. The objective of this study was to estimate the relationship between cycle and production traits using canonical correlation analysis and to identify traits that can be used for the indirect selection of lima bean. The experiment was conducted at the Department of Plant Science of the Universidade Federal do Piauí, Teresina, in a randomized block design with five replications, in which 11 agronomic traits from six lima bean populations in the F3 generation originating from biparental crosses were evaluated in 2019. The data were subjected to canonical correlation analysis using the virtual environment R. The results showed that only the first coefficient of the canonical pair was significant (r = 0.5531) by the quisquare test, suggesting that the studied groups were not independent, as the cycle traits showed coefficients of large magnitudes in the relationship between groups. The canonical correlation results suggested that there is a linear association between cycle and production traits in lima beans, in which days to flowering, days to maturation, pod length, seed width, and seed thickness contribute the most to the association between groups.
اظهر المزيد [+] اقل [-]INCREASES IN SOIL MESOFAUNA THROUGH TREE ESTABLISHMENT AND GRAZING DEFERMENT IN A DEGRADED AREA IN THE CAATINGA BIOME
2022
FERNANDES,SAMARA PAULO DOS SANTOS | BAKKE,OLAF ANDREAS | BAKKE,IVONETE ALVES | GUEDES,ROZILEUDO DA SILVA | MARTINS,KYEGLA BEATRIZ DA SILVA
ABSTRACT Environmental degradation impacts negatively the diversity and quantity of invertebrates living in the soil, mainly in semiarid regions. Generally, a high diversity of invertebrates indicates good biofunctionality and sustainable use of the soil. We evaluated the effects of 14 years of grazing deferment and the presence of the native trees Mimosa tenuiflora and Cnidoscolus quercifolius on the soil mesofauna of a degraded Caatinga area, according to the χ 2 test, applied to assess the abundance of these microorganisms. The grazing deferment alone more than tripled the soil mesofauna. The abundance of the mesofauna under M. tenuiflora canopies increased by a factor of 3.17 and 3.41 in grazed and ungrazed areas, respectively, and under C. quercifolius canopies increased by a factor of 22.6 in the ungrazed area. The effect of M. tenuiflora in the grazed area was similar to 14 years of grazing deferment. The quantity of mesofauna under C. quercifolius canopies after 14 years of grazing deferment was 6.6-fold higher than that under M. tenuiflora canopies, under similar conditions. The grazing deferment and trees, especially C. quercifolius, increased the soil mesofauna; however, full recovery of such organisms in degraded Caatinga areas may need more than 14 years. Considering the current scenario of increasing environmental degradation, our findings regarding the relationships between soil mesofauna, grazing deferment and native trees are important to devise strategies and procedures for the recovery of degraded areas in the Caatinga biome.
اظهر المزيد [+] اقل [-]