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Nascimento J.B.,Federal University of Goais | Barrigossi J.A.F.,Embrapa Rice and Beans | Borba T.C.D.O.,Embrapa Rice and Beans | Martins J.F.D.S.,Embrapa Temperate Agriculture | And 2 more authors.
Crop Protection | Year: 2015

This study aimed to observe the response of 34 rice accessions to attack by sugarcane borer (. Diatraea saccharalis Fabr., 1794) and to analyze the genetic diversity of these accessions by microsatellite markers. Twenty larvae were placed on the leaf sheaths of rice plants. At 30 days after infestation the rice plants at ground level were taken to the laboratory where the signs of borer attack, external and internal diameter of the stem and weight of surviving larvae were determined. For the molecular analysis of rice accessions, 24 microsatellite markers were used. The results of the morphological traits of the rice plant, response of the plant to insect attack, development of the sugarcane borer larvae and molecular data, indicated a genotypic variation. The accessions that most favored larval survival were IAC 47 and Ti Ho Hung. Larvae with highest weight (0.0986g and 0.0862g) and the largest internal diameters of the rice stem (3.18mm) were found in land races "Canela de Ferro" (rust colored stem) and all these "Canela de Ferro" accessions also remained genetically grouped. The most tolerant materials, based on the ability to produce new tillers after larval infestation were, Chiang an Tsao Pai Ku and IR 40 which remained morphological and genetically grouped. The results of this study indicate that all the traits and molecular analyses were able to separate the accessions of rice into different groups in relation to resistance to the sugarcane borer. These materials can be used as donor sources in breeding for genetic resistance to sugarcane borers and can be used as donors to amplify the genetic base of Brazilian rice. © 2014 Elsevier Ltd.

Neitzke R.S.,Embrapa Temperate Agriculture | Jaksch T.,Weihenstephan-Triesdorf University of Applied Sciences | Kohlrausch F.,Weihenstephan-Triesdorf University of Applied Sciences | Rober R.,Weihenstephan-Triesdorf University of Applied Sciences
Acta Horticulturae | Year: 2013

Ornamental peppers are easy to propagate and cultivate. They have a relatively short production cycle and are well accepted by the market. This study aims to evaluate the response of 10 cultivars of ornamental peppers to different fertilization regimes. The experiment was conducted during the autumn season of 2010 in Freising, Germany. The plants were grown in 9 cm pots filled with substrate (commercial peatclay mix; ~80:20 vol.) and fertilized with a fertigation system based on subirrigation using a commercial fertilizer. The pots were placed in a greenhouse and treated during two phases, the first of 5 weeks and the second of 6 weeks, with different concentrations of a nutrient solution. Low fertilization leads to compact plants and high amounts of fertilizer result in large plants. But their ornamental value, determined by the number of the fruits, increases with rising fertilization.

Reis D.A.,Federal University of Pelotas | de Lima C.L.R.,Federal University of Pelotas | Pauletto E.A.,Federal University of Pelotas | Dupont P.B.,Federal University of Pelotas | Pillon C.N.,Embrapa Temperate Agriculture
Scientia Agricola | Year: 2014

Management systems may influence the structural quality of soils. Tensile strength (TS) and friability (F) are indicators of soil structural quality. The aim of this study was to evaluate the TS and F of an Alfisol under different management systems. The treatments were as follows: (i) soil under conventional system with growing maize after tobacco cultivation, (ii) soil under conventional system with growing maize after use as pasture, (iii) soil under natural pasture, and (iv) a natural area with predominance of spontaneous vegetation. TS and F were evaluated at depths of 0.00-0.05 and 0.05-0.10 m. The water content of soil aggregates, soil particle-size distribution, total organic carbon, carbon in the coarse fraction and carbon associated with minerals were also determined. The increase in clay content and soil organic carbon influences the values of TS. The lowest TS was for the soil under maize cultivation after tobacco in the conventional system. Soil under natural area in the 0.05-0.10 m layer was classified as slightly friable, while other systems were classified as friable. Evaluations of the structural quality of soils under management systems can be performed using TS. However, F was not efficient in detecting changes between the different management systems.

Tesio F.,ValOryza Sas 55 | Follis F.,ValOryza Sas 55 | Andres A.,Embrapa Temperate Agriculture
Experimental Agriculture | Year: 2014

Cultivation of less productive soils such as closed landfills has become convenient because European subsidies covered part of the risk to obtain production. Aim of the research was to evaluate grain yields of maize hybrids belonging to different maturity classes (FAO 200, 300 and 400) (Gretzmacher, R. (1979). Die Bodenkultur 30:256 - 280) grown on closed landfills by the adoption of two minimum tillage methods (chisel plowing at 0.35 m plus disk harrowing at 0.20 m, or only disk harrowing at 0.20 m). Maize cultivation inserted in a winter cereal rotation had a grain production ranging from 4.6 t ha-1 (FAO 200, disk harrowing only) to 8.3 t ha-1 (FAO class 400, chisel plowing plus disk harrowing) in the two considered years (2011 and 2012). The adoption of chisel plowing coupled with disk harrowing reduced yield fluctuation between years, and furnished higher yield performance if compared with the single disk harrowing passage. The best growing hybrid cycles were those belonging to FAO class 300 with production similar to that of the longest maturity class, and with moisture content equal to the shortest maturity class. Copyright © Cambridge University Press 2013.

Palhares J.C.P.,Embrapa Cattle Southest | Guidoni A.L.,Embrapa Temperate Agriculture | Steinmetz R.L.R.,Embrapa Swine and Poultry | Mulinari M.R.,Embrapa Swine and Poultry | Sigua G.C.,U.S. Department of Agriculture
Archivos de Zootecnia | Year: 2012

Brazil is one of the largest producers of food in the world. Agriculture and livestock production are concentrated in certain regions of the country. Livestock has been perceived as a constant threat to the quantity and quality of water resources. The objective of this study was to evaluate the impact of mixed farms on superficial water quality in Pinhal River sub-basin, which is located in Concordia, Santa Catarina State. Eight sampling sites representing different land-uses (LU1: dairy cattle; LU2: without animals; LU3: dairy + pigs + poultry + crops; LU4: pigs + poultry + crops; LU5: dairy + pigs + poultry + crops + human; LU6: dairy + pigs + crops; LU7 and LU8: dairy + pigs) were evaluated. These sampling sites were assessed longitudinally and sampled during the summer, spring, autumn, and winter of 2006 to 2009. LU1 presented the worst water quality with high concentrations of total suspended solids (TSS) and chemical oxygen demand. In this point, cows had access to the river. The highest concentration of nitrate (NO3-N) was found at the estuary of the river. There were higher concentrations of TSS, NO3-N and NO2-N in wet season. At this time, intensive fertilizer application to corn fields is common. Autumn and winter presented the worst water quality with respect to nitrogen concentration. Results showed a strong relationship between the sources of pollution (e.g., cows, pigs and poultries) and water quality. Managing the use of animal manure with optimum chemical fertilizer applications along with riparian fencing may provide important mitigation options for protecting water quality of Pinhal River.

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