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11.
Marcelo Luiz Laia Acelino Couto Alfenas Sergio Hermnio Brommonschenkel Shinitiro Oda Eduardo Jose de Melo Inae Marie de Arau jo Silva Janana Fernandes Goncalves Ariadne Marques 《林业研究》2015,(3)
Disease-resistant genes play an important role in defending against a variety of pathogens and insect pests in plants. Most of the disease-resistant genes encode pro-teins with conserved leucine rich r... 相似文献
12.
Carmen Lucia de Souza Rech José Luiz Rech Vivian Fischer Mabel Mascarenhas Wiegand Heden Luiz Marques Moreira Maria Teresa Moreira Osório Frank Siewerdt 《Tropical animal health and production》2014,46(1):191-195
The objective of this trial was to evaluate the effect of whole rice meal (WRM) inclusion in the concentrate upon body development, carcass traits, and meat quality of lambs. Twenty-four castrated lambs with an average initial body weight of 17.90?±?2.72 kg were randomly blocked according to two genetic groups (Corriedale and Texel by Corriedale crossbreds). Three isocaloric (11.3 MJ/kg of metabolizable energy) and isonitrogenous (17 % crude protein) diets were offered to the animals for 74 days. Diets consisted of 40 % forage and 60 % concentrate diet, on a dry matter basis, with 0, 15, or 30 % of WRM inclusion into the concentrate. Body growth (after slaughter), carcass, and meat traits were evaluated on each animal. Results obtained indicated that genotype did not affect body growth, carcass, and meat traits except for yellowness. No significant interaction between diet and genotype were detected. Inclusion of up to 30 % WRM did not significantly (P?>?0.05) affect body growth, carcass, and meat traits, except for meat color. Meat luminosity progressively increased (36.32?+?0.055X) while redness (15.13???0.03X) decreased with the inclusion of WRM in the diet, but still remained within acceptable values. The study indicates that WRM may be included up to 30 % in the concentrate replacing corn without adverse effects upon body development, carcass traits, and meat quality of lambs. 相似文献
13.
Maria Margarida Ribeiro Leopoldo Sanchez Carla Ribeiro Fátima Cunha José Araújo Nuno M. G. Borralho Cristina Marques 《Annals of Forest Science》2011,68(4):701-714
• Introduction
Tree genetic improvement programs usually lack, in general, pedigree information. Since molecular markers can be used to estimate the level of genetic similarity between individuals, we genotyped a sample of a Portuguese Eucalyptus globulus breeding population—a reference population of 125 individuals—with 16 microsatellites (SSR). 相似文献14.
Marques L Mezouar M Hodeau J Nunez-Regueiro M Serebryanaya NR Ivdenko VA Blank VD Dubitsky GA 《Science (New York, N.Y.)》1999,283(5408):1720-1723
High-pressure studies on fullerenes have previously shown the existence of one- and two-dimensional (2D) polymerized C60 structures. Synchrotron radiation measurements, performed on C60 samples quenched from 13 gigapascals and 820 kelvin, yield unambiguous proof for the existence of a three-dimensional (3D) polymerized C60 derivative. Moreover, unusual ellipsoidal Debye-Scherrer diffraction patterns are observed, which shows that the giant anisotropic deformation induced by the nonhydrostatic compression is retained in the quenched samples. The multiple bonding possibilities of the highly symmetrical C60 allow the retention (down to ambient pressure) of the deformation, a phenomenon reported previously only under high pressure. 相似文献
15.
J.?M.?SerranoEmail author S.?Shahidian J.?Marques?da?Silva M.?Carvalho 《Precision Agriculture》2016,17(3):274-295
Soil organic carbon (SOC) plays a vital role in determining the susceptibility to land degradation. The recommended procedure for the recovery of the characteristic poor soils of the Southern region of Portugal is the installation of grazed permanent pastures and increase of soil fertility. The objectives of this study were: (i) to identify the spatial and temporal patterns of soil nutrients at four points in time over a 10-year period in a perennial pastureland; (ii) to test new tools for survey of the spatial variability of soil nutrients; (iii) to evaluate the potential for differential organic management. A 6 ha permanent bio-diverse pasture field, grazed by sheep and improved by annual application of super phosphate fertilizer, was installed on a shallow soil in Mediterranean conditions. Spatial variability and temporal stability of topsoil macronutrients (phosphorus, nitrogen and potassium), SOC and pH were measured. The results indicate that SOC and pH have great potential for implementing differential management. In the case of SOC, the management classes map shows that over 80 % of the area has temporal stability, while more than 50 % of the area has low levels of SOC (<10 g kg?1), justifying the potential for differential application of C-rich organic soil amendments. The geospatial measurements of apparent soil electrical conductivity (ECa) and NDVI index showed significant correlation between these parameters and soil properties, revealing the potential of these tools for producing detailed soil maps, decisive for understanding the changes in soil properties under sustainable management systems. 相似文献
16.
The in vitro formation of newly formed adventitious buds and shoots from internodal branch segments was studied on 12-month-old plants of Citrus aurantium L. cv. Brazilian. The effects of 6-Benzyladenine (BA) and α-Naphthalene acetic acid (NAA) treatments were evaluated on adventitious bud and shoot regeneration. High rates of bud initiation and shoot development were obtained both with BA supplemented medium, in the range from 1 mg L−1 to 3 mg L−1, and with 0.1 mg L−1 NAA supplemented medium. NAA concentrations above 1 mg L−1 significantly reduced bud initiation and shoot elongation. The results obtained using different in vitro culture vessels such as Petri dishes, tubes and glass culture jars were compared. The highest adventitious bud induction was observed in Petri dishes for internodes cultured in 2 mg L−1 BA supplemented medium, with 95% responsive explants forming 9.0 ± 2.4 adventitious buds. The adventitious buds observed in Petri dishes reached a maximum height of 1 mm, with no further development, while some of the adventitious shoots cultured in tubes and glass culture jars grew over 1 cm in height. A shoot regeneration gradient of the internodes collected along the branch axis was noticed, with basal ones exhibiting higher regeneration frequency. 相似文献
17.
18.
André MR Adania CH Teixeira RH Allegretti SM Machado RZ 《Journal of zoo and wildlife medicine》2011,42(1):139-143
Large and small piroplasms have been observed in the blood smears of various wild carnivores, but few studies utilizing molecular characterization have been done. The goal of this present study was to investigate the presence of Babesia sp. by molecular and serologic techniques in exotic and neotropical carnivores maintained in captivity at Brazilian zoos. Blood and sera samples were collected from 146 Brazilian wild felids, 21 exotic felids, 1 genet (Genetta tigrina), 3 European wolves (Canis lupus), and 94 Brazilian wild canids in Brazilian zoos in the S?o Paulo and Mato Grosso states and in the Federal District. A total of 53 wild felids (31.74%) and 10 wild canids (10.31%) were seropositive for Babesia canis by Indirect Fluorescent Antibody Test (IFAT). Antibodies were detected in ocelots, little-spotted cats, margays, pampas cats, jaguars, pumas, jaguarundis, crab-eating foxes, and bush dogs. Babesia sp. DNA, with high similarity to B. leo, was detected in one pampas cat and one genet. 相似文献
19.
Margarida C. Marques Gode Gravenhorst Andreas Ibrom 《Water, air, and soil pollution》2001,130(1-4):571-576
In this study the dry input of atmospheric particles into a forest stand is quantified. A wash-off-method using the natural leaf surfaces as collectors of the dry deposition was chosen. The direct on-site-measurement on living branches were achieved in a spruce stand (Picea abies (L.) Karst) at Solling, Germany. The ion exchange processes occurring on natural branches can reliably be quantified through immediate sequential washings. In order to calculate also the gas dry deposition of those trace elements which occur in both particle and gas phases, a resistance model was used. From these results the deposition velocity of particulate aerosol components into the forest stand was calculated. Dry particle deposition constitutes an important part of the total matter input into the forest ecosystem. Just the nitrogen input into Solling only by dry deposition (from particle-, mist-, and gas-deposition) with about 30 kg N ha?1 a?1 already exceeds the critical load of 20 kg N ha?1 a?1 by far, and this is without even considering the additional load by wet deposition which amounts to 15 kg ha?1 a?1. These findings are of greatest ecological importance, as the damage to the stability of the forest ecosystem caused by increased nitrogen input is considerable. Only a quick and drastic reduction of sulphur and nitrogen emissions could stop the further increase of the nutritient imbalance and the progressing acidification of this ecosystem. 相似文献
20.
Carbon dioxide emissions after application of tillage systems for a dark red latosol in southern Brazil 总被引:3,自引:0,他引:3
Soil tillage may influence CO2 emissions in agricultural systems. Agricultural soils are managed in several ways in Brazil, ranging from no tillage to intensive land preparation. The objective of this study was to determine the effect of common soil tillage treatments (disk harrow, reversible disk plow, rotary tiller and chisel plow tillage systems) on the intermediate CO2 emissions of a dark red latosol, located in southern Brazil. Different tillage systems produced significant differences in the CO2 emissions, and the results indicate that the chisel plow produced the highest soil carbon loss during the 15 days period after tillage treatments were performed. Emissions to the atmosphere increased as much as 74 g CO2 m−2, at the end of a 2-week period, in the plot where the chisel plow treatment was applied, in comparison to the non-disturbed plot. The results indicate that the total increase on the intermediate term soil CO2 emissions due to tillage treatments in southern Brazil is comparable to that reported for the more humid and cooler regions. 相似文献