Barra de Santo Antônio, Brazil
Barra de Santo Antônio, Brazil

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PubMed | Federal University of Goais, Embrapa Rice and Beans, Brazilian National Council for Scientific and Technological Development, University of Wisconsin - Madison and University of California at Davis
Type: Evaluation Studies | Journal: PloS one | Year: 2016

This research evaluated a multivariate approach as an alternative tool for the purpose of selection regarding expected progeny differences (EPDs). Data were fitted using a multi-trait model and consisted of growth traits (birth weight and weights at 120, 210, 365 and 450 days of age) and carcass traits (longissimus muscle area (LMA), back-fat thickness (BF), and rump fat thickness (RF)), registered over 21 years in extensive breeding systems of Polled Nellore cattle in Brazil. Multivariate analyses were performed using standardized (zero mean and unit variance) EPDs. The k mean method revealed that the best fit of data occurred using three clusters (k = 3) (P < 0.001). Estimates of genetic correlation among growth and carcass traits and the estimates of heritability were moderate to high, suggesting that a correlated response approach is suitable for practical decision making. Estimates of correlation between selection indices and the multivariate index (LD1) were moderate to high, ranging from 0.48 to 0.97. This reveals that both types of indices give similar results and that the multivariate approach is reliable for the purpose of selection. The alternative tool seems very handy when economic weights are not available or in cases where more rapid identification of the best animals is desired. Interestingly, multivariate analysis allowed forecasting information based on the relationships among breeding values (EPDs). Also, it enabled fine discrimination, rapid data summarization after genetic evaluation, and permitted accounting for maternal ability and the genetic direct potential of the animals. In addition, we recommend the use of longissimus muscle area and subcutaneous fat thickness as selection criteria, to allow estimation of breeding values before the first mating season in order to accelerate the response to individual selection.

Pires L.P.M.,Federal University of Lavras | Ramalho M.A.P.,Federal University of Lavras | Abreu A.F.B.,Embrapa Rice and Beans | Ferreira M.C.,University of Sao Paulo
Scientia Agricola | Year: 2014

Plant with a more upright architecture offers many advantages to farmers. Recurrent mass selection (RS) programs for carioca type common bean have been implemented for the purpose of obtaining new lines that will generate the high yields that are associated with upright plant architecture. This study aimed to assess the efficiency of recurrent mass selection (RS) for upright plant architecture in common bean (Phaseolus vulgaris) and the effect of RS on grain yield and to verify whether or not there is still variability in the population that favors continuing selection programs, using information obtained from progenies evaluated in cycle five (CV) and cycle eight (CVIII) of the RS program. Mass selection for more upright plants was performed visually in the "S0" generation before flowering. Progenies S0:3 and S0:4 were evaluated in 2009 (CV) and 2011 (CVIII). Heritability (h2) and RS progress were estimated using adjusted means. After eight selection cycles, the population subjected to RS still had enough genetic variability to achieve continued success through recurrent selection. The RS progress was 1.62 % per cycle for the growth habit scores and 6.81 % for grain yield.

Mascarin G.M.,Embrapa Rice and Beans | Mascarin G.M.,National United University | Mascarin G.M.,University of Sao Paulo | Jackson M.A.,National United University | And 3 more authors.
Journal of Invertebrate Pathology | Year: 2015

A major constraint to the commercial use of fungal biocontrol agents is the availability of low-cost production media and processes. Previous attempts in producing Beauveria blastospores using liquid culture fermentation processes required long fermentation times (6-8days) and produced cells that had poor survival after desiccation and storage. In this study, isolates of Beauveria bassiana and Isaria fumosorosea were evaluated for blastospore yield, desiccation tolerance, storage stability, and biocontrol efficacy using fermentation media containing acid hydrolyzed casein or cottonseed flour as the nitrogen source. Cultures of B. bassiana and I. fumosorosea grown in media containing cottonseed flour produced high blastospore concentrations (>1×109mL-1) after 3days which is comparatively less expensive nitrogen source than acid hydrolyzed casein. The resultant air-dried blastospores (<3% moisture) of all fungal isolates survived drying (61-86% viability), irrespective of the nitrogen source tested. Storage stability at 4°C varied with nitrogen source and fungal strain. Air-dried blastospores of B. bassiana strains showed half-lives >14months in contrast to 9.2-13.1months for I. fumosorosea. Blastospores of B. bassiana and I. fumosorosea killed Bemisia tabaci whitefly nymphs faster and required lower concentrations compared with aerial conidia. Our findings support the use of liquid culture fermentation as a cost-effective process to rapidly produce high yields of stable and infective blastospores of either B. bassiana or I. fumosorosea. These results support further evaluation of blastospore sprayable formulations for the control of soft-bodied insects. © 2014 Elsevier Inc.

Colombari Filho J.M.,Embrapa Rice and Beans | Geraldi I.O.,University of Sao Paulo
Crop Breeding and Applied Biotechnology | Year: 2014

In plant breeding programs, the knowledge about the appropriate sample size for the evaluation of populations is very important. A small sample reduces the chance of selecting superior genotypes, whereas a very large sample may lead to unnecessary increases in cost and labor. A population consisting of 192 soybean lines was divided in groups of 24 lines, which were assessed for grain yield in eight randomized complete block experiments. Analyses of variance were performed for each experiment as well as for groups of experiments, resulting in analyses of variance consisting of 24, 48, 72, 96, 120, 144, 168, and 192 lines. As the sample size increased, the width of confidence intervals of parameter estimates decreased, stabilizing with samples of 144 lines. Therefore, an appropriate sample size for the evaluation of soybean inbred populations should contain about 150 lines.

Moreira A.S.,Embrapa Rice and Beans | Filho A.B.,University of Sao Paulo | Rezende J.A.M.,University of Sao Paulo
Journal of Phytopathology | Year: 2015

Zucchini yellow mosaic virus (ZYMV), Papaya ringspot virus - type W (PRSV-W) and Zucchini lethal chlorosis virus (ZLCV) cause important diseases on zucchini squash crops in Brazil. ZYMV and PRSV-W belong to the genus Potyvirus and are transmitted by aphids, whereas ZLCV belongs to Tospovirus and is transmitted by the thrips Frankliniella zucchini. These three viruses may occur simultaneously in the field, and the epidemiology of the corresponding diseases may be determined by interactions among viruses, hosts and vectors. In this work, the progress of the diseases caused by these viruses was studied over a temporal and geographic range for three planting seasons (PS). For the lethal chlorosis (ZLCV), a monomolecular model was found to be the best fit for the data, though only during the third PS. For data collected during the first two PS, the Gompertz model was found to fit the data best. The spatial distribution of disease indicated disease aggregation at the end of the crop cycle. For the yellow mosaic (ZYMV), the model that best fit in the 1st PS was the logistic and in the 2nd and 3rd PS was monomolecular. The spatial pattern of the disease was random when the disease incidence was low but aggregated when the disease incidence was high. The common mosaic (PRSV-W) showed the lowest incidence in all three PS. An exponential model was the best fit for data collected during all PS, and the spatial pattern of the disease was random. Interactions among the three viruses apparently did not result in changes in the epidemiology of the diseases. Removal of sources of inoculum and planting at an unfavourable time for reproduction of virus vectors are the two main measures recommended for the control of these diseases. The use of insecticide is indicated only for the control of the F. zucchini. © 2014 Blackwell Verlag GmbH.

Garcia R.A.V.,Federal University of Goais | Rangel P.N.,Monsanto Corporation | Bassinello P.Z.,Embrapa Rice and Beans | Brondani C.,Embrapa Rice and Beans | And 3 more authors.
Euphytica | Year: 2012

The decrease in the per capita consumption of beans has been partially attributed to their lengthy cooking time and the aggregated capital costs of their preparation. The aim of this study was to map microsatellite (SSR) markers linked to quantitative trait loci (QTLs) that govern the cooking time of common beans. An F 2 generation consisting of 140 families was generated from a cross between lines CNFM7875 and Laranja. The cooking time of the F 2:4 and F 2:5 generations was then evaluated, and the latter generation was tested in two environments. The analysis of variance found a significant effect for the interactions between the families (P < 0.01) in both the F 2:4 and F 2:5 generations, as well as for the group analyses performed in the two environments. The experimental coefficient of variation varied from 9.42 to 17.94%. The Pearson's correlation test indicated no significant association between water absorption and cooking time. The heritability coefficients had values of 0.532 and 0.739 for the F 2:5 families evaluated at the two different locations, and the group analysis of the F 2:5 generation indicated that there was a significant genotype × environment interaction. Of the 105 polymorphic SSRs evaluated, 91 mapped to 12 linkage groups with an estimated map size of 1,303. 7 cM. Six significant QTLs were detected in both environments, and the percentage of the phenotypic variation that was explained by these loci ranged from 11.54 to 21.63%. As the genetic control was oligogenic, the identification of QTLs should serve as an optimal starting point for the implementation of a selection program. © 2011 Springer Science+Business Media B.V.

Mascarin G.M.,Embrapa Rice and Beans | Kobori N.N.,Embrapa Rice and Beans | de Jesus Vital R.C.,Embrapa Rice and Beans | Jackson M.A.,National United University | Quintela E.D.,Embrapa Rice and Beans
World Journal of Microbiology and Biotechnology | Year: 2014

We investigated the potential production and desiccation tolerance of microsclerotia (MS) by Brazilian strains of Metarhizium anisopliae (Ma), M. acridum (Mc) and M. robertsii (Mr). These fungi were grown in a liquid medium containing 16 g carbon l-1 with a carbon:nitrogen ratio of 50:1. One hundred milliliters cultures were grown in 250 ml Erlenmeyer flasks in a rotary incubator shaker at 28 °C and 200 rpm for 5 days. Five-day-old MS were harvested, mixed with diatomaceous earth (DE) and air-dried for 2 days at 30 °C. The air-dried MS-DE granular preparations were milled by mortar + pestle and stored in centrifuged tubes at either 26 or -20 °C. Desiccation tolerance and conidia production were assessed for dried MS granules by measuring hyphal germination after incubation for 2 days on water agar plates at 26 °C and for conidia production following 7 days incubation. Yields of MS by all strains of Metarhizium were 6.1-7.3 × 106 l-1 after 3 days growth with maximum MS yields (0.7-1.1 × 107 l-1) after 5 days growth. No differences in biomass accumulation were observed after 3 days growth, whereas Ma-CG168 showed the highest biomass accumulation after 5 days growth. Dried MS-DE preparations of all fungal strains were equally tolerant to desiccation (≥93 % germination) and the highest conidia production was obtained by MS granules of Mc-CG423 (4 × 109 conidia g-1). All MS granules showed similar stability after storage at either 26 or -20 °C for 3.5 months. © 2013 Springer Science+Business Media Dordrecht.

Geraldine A.M.,Federal University of Goais | Lopes F.A.C.,Federal University of Goais | Carvalho D.D.C.,University of Brasilia | Barbosa E.T.,Embrapa Rice and Beans | And 4 more authors.
Biological Control | Year: 2013

Field outcomes of 10 Trichoderma spp. isolates against white mold (Sclerotinia sclerotiorum) on common beans were matched to laboratory results, to identify the causes of variance related to biocontrol effectiveness. Laboratory assays estimated sclerotia parasitism and production of the cell wall-degrading enzymes (CWDEs) lipase, NAGase, β-1,3-glucanase, β-glucosidase and protease. Field trials were carried out in 2009 and 2010 under a randomized block design and sprinkling irrigation, where 2×1012sporesmL-1 of each antagonist were applied to the plots at the early R5 stage. The density of S. sclerotiorum apotheciam-2 and disease severity were assessed, respectively at R7 and R8 stages, with yield and its components also estimated for each year. Field results were analyzed jointly by the Tukey-Kramer multiple comparison test, and all variables from both field and laboratory experiments were subjected to principal component analysis (PCA). In both years, isolates TR696 and TR356 of Trichoderma asperellum were effective in reducing apothecia density and disease severity. Biocontrol increased the number of pods per plant and yields up to 40% when compared to controls, even under higher disease pressure in 2010. PCA demonstrated in 2009 and 2010 that apothecia density, disease severity, NAGase, β-1,3-glucanase and number of pods were the main sources of the first component of variance. Such results suggest that the CWDEs NAGase and β-1,3-glucanase and sclerotia parasitism are key components of Trichoderma spp. action in biocontrol of S. sclerotiorum in the field, and may be used as markers to hasten the selection of new, promising isolates. © 2013 Elsevier Inc.

Siqueira B.D.S.,Federal University of Goais | Vianello R.P.,Embrapa Rice and Beans | Fernandes K.F.,Federal University of Goais | Bassinello P.Z.,Embrapa Rice and Beans
LWT - Food Science and Technology | Year: 2013

Instrumental texture analysis is a fast and practical tool that has been used to assess bean cooking quality. However, lack of standardization for sample preparation has resulted in quite divergent reports in literature. So, five bean cooking methods were evaluated to identify and establish the best one that differentiates hardness of fresh and aged grains. Bean hardness was highly affected by cooking time and temperature. Mattson Bean Cooker and hot air oven were not adequate, providing undercooked grains with hardness above 4N. Hardness of grains cooked on a hotplate decreased as the cooking time increased from 30 to 60min. Likewise, with the autoclave at milder condition (105°C/10min) the grains were harder (2.99N for fresh grains and 3.40N for aged grains), while at severe condition (115°C/20min) softer grains were obtained (0.77N for fresh grains and 1.01N for aged grains). The suitable methods to prepare cooked bean for instrumental texture analyses seem to be the hotplate cooking for 45 or 60min and the autoclave procedure at 110°C/15min, once they promoted the grain softening and discriminated fresh and aged beans. © 2013 Elsevier Ltd.

de Aguiar R.A.,Federal University of Goais | da Cunha M.G.,Federal University of Goais | Lobo Junior M.,Embrapa Rice and Beans
Biological Control | Year: 2014

Field trials were carried out to evaluate six treatments combining biological agents and chemical fungicides applied via chemigation against white mold (Sclerotinia sclerotiorum) on processing tomatoes. The experiment was performed in Goiânia, Brazil, with tomato hybrid Heinz 7155 in 2009 and 2010 in a field previously infested with S. sclerotiorum sclerotia. Treatments were arranged in a randomized complete block design in a 2×3 factorial structure (with and without Trichoderma spp. 1.0 ×109 viable conidia mL-1 ha-1) ×fluazinam (1.0Lha-1), procimidone (1.5Lha-1) and control, applied by drip irrigation. Treatments were applied three times 10days apart, starting one month after transplanting. Each treatment consisted of plots with three 72-meter rows with four plants m-1 and 1.5m spacing between rows, with three replications. Based on disease incidence evaluated weekly, the area under the disease progress curve (AUDPC) was obtained. Yield and its components were evaluated in addition to fruit pH and °Brix. Results were subjected to ANOVA, Scott-Knott (5%), and regression analysis. Biocontrol using Trichoderma spp. via chemigation singly or in combination with synthetic fungicides fluazinam and procimidone reduced AUDPC and increased fruit yield up to 25tha-1. The best treatment for controlling white mold also increased pulp yield around 1.0 and 7.0tha-1 in 2009 and 2010, respectively. The present work demonstrated the advantages of white mold biological control in processing tomato crops, where drip irrigation favored Trichoderma spp. delivery close to the plants and to the inoculum source. © 2014 Elsevier Inc.

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