Tropical Rice Cultivars from Lowland and Upland Cropping Systems Differ in Iron Plaque Formation     

Eduardo Gusmão Pereira  Marco Antonio Oliva  Advânio Inacio Siqueira-Silva  Laíse Rosado-Souza  Daniel Teixeira Pinheiro  Andréa Miyasaka Almeida 《Journal of plant nutrition》2014,37(9):1373-1394

In iron toxic wetlands, ferric hydroxide is commonly deposited on rice roots. This study aims to to evaluate the differences in iron plaque formation in rice cultivars from different cropping systems. Thirty days old seedlings of Brazilian rice cultivars from the lowland cropping system (‘BRS Atalanta’ and ‘Epagri 107’) and upland cropping system (‘Canastra’) or both systems (‘BRSMG Curinga’) and the cultivar ‘Nipponbare’ were exposed to iron excess [4 mM iron sulfate heptahydrate (FeSO₄.7H₂O)] for seven days in nutrient solution. It was observed iron plaque formation and ruptures of the root epidermal cells. The lowland cultivars showed higher Fe content in iron plaque. Iron stain was detected in the root hairs, epidermis, hypodermis, and exodermis. The root exodermis may be contributed to prevent the deposit of iron in the cortex of the lowland cultivars and in the cultivar ‘BRSMG Curinga’. It was observed in plants with iron plaque formation significant reductions in the shoot content of phosphorous, manganese and magnesium due to different causes. The differences in iron plaque formation among the cultivars might be an indicative of variations in exodermis selectivity, root oxidative capacity, and iron nutrition mechanisms.  相似文献   

Detection of Toxoplasma gondii DNA in Fresh and Frozen Semen from Rams in Brazil     

MJG Bezerra  JALO Cruz  ES Kung  PPF Albuquerque  PCP Kim  EPBX Moraes  JW Pinheiro Júnior  RA Mota 《Reproduction in domestic animals》2014,49(5):753-755

The aim of this study was to estimate the prevalence of genomic DNA of Toxoplasma gondii in semen samples from commercial rams in artificial insemination centres in Brazil, as well as in fresh semen from rams in the northeast of Brazil. In total, 108 semen samples were obtained from artificial insemination centres, and genomic DNA of T. gondii was detected in 24 of 108 (22.2%). The prevalence of antibodies anti‐Toxoplasma gondii among sheep on rural properties was 9.2% (10/109), and 100% of the semen samples of these animals were positive in the PCR for T. gondii DNA. The molecular identity was confirmed through sequencing, which indicated 99.9% similarity with the T. gondii DNA sequences stored in the GenBank. This study reports the first occurrence of T. gondii DNA in the semen of rams, which came from artificial insemination centres in Brazil, as well as the occurrence of T. gondii DNA in the fresh semen of naturally infected rams in the northeast of Brazil.  相似文献   

Compatibility of the fungus Metarhizium anisopliae and deltamethrin to control a resistant strain of Boophilus microplus tick   总被引：1，自引：0，他引：1  

Bahiense TC  Fernandes EK  Bittencourt VR 《Veterinary parasitology》2006,141(3-4):319-324

The tick Boophilus microplus causes economic impact to cattle producers and has a great capacity to develop resistance to chemical acaricides. It is very important the development of new techniques to complement the control of this parasitosis. Biological control is a promising option to maintain acceptable levels of tick populations in cattle. Therefore, the present study evaluated the association of deltamethrin and the entomopathogenic fungus Metarhizium anisopliae against B. microplus larvae resistant to pyrethroid. The synthetic pyrethroid, deltamethrin, was used at concentrations of 0.39, 0.78, 1.56, 3.12 and 6.12 ppm, M. anisopliae was used at concentrations of 10(5), 10(6), 10(7) and 10(8) conidia ml(-1). Their associations were also evaluated in in vitro tests. The assays showed that the tick strain is resistant to deltamethrin, but high mortality rates were observed when deltamethrin was associated with the entomopathogen. The larvae's mortality rates ranged from 7 to 36.5% for the different concentrations of deltamethrin, however, for the different concentrations of M. anisopliae, the mortality rates ranged from 10 to 96.9%. Mortality rates were proportional to the concentrations used for both deltamethrin and the fungus. Predominantly, the association of pyrethroid and fungus resulted in higher larvae mortalility rates than those obtained with the respective non-associated concentrations. Thus, the present study indicates that this association can be used as a tool for integrated control of the tick B. microplus.  相似文献   

Prediction of carcase and breast weights and yields in broiler chickens using breast volume determined in vivo by real-time ultrasonic measurement     

Silva SR  Pinheiro VM  Guedes CM  Mourão JL 《British poultry science》2006,47(6):694-699

1. The use of in vivo real-time ultrasonic (RTU) to predict breast and carcase weights and yields in 103 male broiler chickens was evaluated. Breast area (mm(2)), thickness (mm) and volume (cm(3)) were measured by RTU in three identified sites. After RTU measurements, the broiler chickens were weighed (live weight, LW, g) and slaughtered Carcase and breast weights (g) and physical measures of breast area (mm(2)), and thickness (mm) corresponding to the three identified sites, and volume (cm(3)) were recorded. 2. The best simple correlation between RTU and carcase measurements was obtained for breast volume. Breast and carcase weights were well predicted by LW. Furthermore, breast volume measured in carcase or by RTU was better in predicting breast weight and breast and carcase yields. 3. Multiple regression equations were fitted using LW (g) and RTU measurement of breast volume to predict breast and carcase weights and yields. The coefficients of determination were 0.52 and 0.65 for breast and carcase yields, respectively, and 0.92 and 0.99 for breast and carcase weights, respectively.  相似文献   

Effects of small hydropower plants on fish assemblages in medium‐sized streams in central and northern Portugal     

Jos M. Santos  Maria T. Ferreira  Antnio N. Pinheiro  Jorge H. Bochechas 《水产资源保护:海洋与淡水生态系统》2006,16(4):373-388

• 1. Over the last decade the development of small hydropower projects has been one of the most active areas of the energy sector. One of the main environmental challenges faced by such projects is related to fish passage.
• 2. The impact of 18 small hydropower plants (SHPs) with distinct levels of fish‐pass effectiveness was investigated in the summers of 1998 and 1999 by comparing fish assemblage composition and structure at 36 sites, above and below SHPs.
• 3. With regard to effectiveness, it was estimated that eight (44.4%) of the surveyed passage facilities were suitable for target species, whereas the remaining 10 (55.6%) were considered unsuitable. In neither case did the composition of fish assemblages upstream and downstream from SHPs differ significantly, while assemblage similarity was relatively high.
• 4. Multivariate techniques identified cover, depth and coarse substrate as the main parameters structuring fish assemblages. It is suggested that these variables have created a rich, patchy, heterogeneous habitat, thereby providing satisfactory resources and favourable conditions required by fish and contributing to the maintenance of assemblages.
• 5. Although populations of some species that occurred both upstream and downstream from SHPs have developed differences in their size structures, SHP‐induced fragmentation of fish populations may not necessarily result in genetic divergence among semi‐isolated populations.

Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

Antioxidant in Mango (<Emphasis Type="Italic">Mangifera indica</Emphasis> L.) Pulp     

Rocha Ribeiro SM  Queiroz JH  Lopes Ribeiro de Queiroz ME  Campos FM  Pinheiro Sant'ana HM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):13-17

This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid). Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography. Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g (Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet.  相似文献   

Viability,storage and ultrastructure analysis of Aechmea bicolor (Bromeliaceae) pollen grains,an endemic species to the Atlantic forest     

Everton Hilo de Souza  Fernanda Vidigal Duarte Souza  Mônica Lanzoni Rossi  Nathalia Brancalleão  Carlos Alberto da Silva Ledo  Adriana Pinheiro Martinelli 《Euphytica》2015,204(1):13-28

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Factors contributing to the development of aluminum resistance in the Madeiran maize germplasm     

Miguel . A. Pinheiro de Carvalho  Jan J. Slaski  Ivo Abreu  Filipe T. Ganana  Teresa M. M. dos Santos  Lurdes Freitas  Maria R. Clemente Vieira  Antonieta Nunes  Ana Domingues  Gregory J. Taylor 《植物养料与土壤学杂志》2004,167(1):93-98

Forty genotypes representing maize genetic diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of maize were obtained from local farmers from field plots spread around the island in a range of altitudes from 99 to 1000 m above sea level. The content of ionic aluminum and the pH of soils cultivated with maize were determined. The mean pH value of all examined soils was 4.9, while the mean ionic Al content was 0.76 cmol kg^–1. Seventy‐two hours (h) exposure to 100 and 200 μM Al followed by a 48 h recovery period of 4‐day old seedlings revealed significant differences in Al resistance in the Madeiran maize germplasm. Root survival and regrowth exceeding 80 % of the seedlings were observed in 22 and 8 of the tested genotypes screened at 100 and 200 μM Al in nutrient solution. High Al resistance among Madeiran maize genotypes appeared not to be associated with the lower pH of soil, and did not correlate with the amount of soil Al³⁺ or the altitude at the site of collection. The high level of Al resistance of the maize cultivars indicates an initial genetic trait enhanced by open pollination of maize.  相似文献   

Soil Surface‐Active Fauna in Degraded and Restored Lands of Northeast Brazil     

Ademir Srgio Ferreira de Araújo  Nico Eisenhauer  Luís Alfredo Pinheiro Leal Nunes  Luiz Fernando Carvalho Leite  Simone Cesarz 《Land Degradation \u0026amp; Development》2015,26(1):1-8

Land degradation reducing vegetation cover may affect the soil surface‐active fauna because both aboveground and belowground invertebrates depend on complex plant communities. In this study, we evaluated the effect of land degradation and restoration on soil fauna in northeast Brazil. Sites differed in degradation status: native vegetation, moderately degraded land, highly degraded land, and land under restoration for 4 years. Araneae and Coleoptera densities were significantly higher in natural vegetation and restored land (8 ± 4 ind./trap and 41 ± 21 ind./trap, respectively) than in degraded lands (−73% and −81%, respectively). The density of Formicidae was significantly higher in natural vegetation (206 ± 181 ind./trap) than in highly degraded land (32 ± 24 ind./trap), while restored land (51 ± 10 ind./trap) and moderately degraded land (37 ± 14 ind./trap) did not differ significantly from the other degradation levels. The density of Orthoptera did not follow the aforementioned patterns, while invertebrate groups mostly had highest densities in natural land and restored land. Linear regressions showed a strong negative relation between faunal density and soil bulk density, and a positive relation with soil organic matter due to an increase in plant cover. Our results indicate that land degradation simplifies soil surface‐active invertebrate communities with pronounced decreases in the density of Araneae, Coleoptera, and Formicidae, but that land restoration practices may recover the density of soil fauna even after only 4 years. Araneae, Coleoptera, and Formicidae respond sensitively to land degradation and restoration practice and are suggested as indicator groups for restoration success. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Iris biopsy to investigate feline iris hyperpigmentation     

Heidi J. Featherstone  Emma J. Scurrell  Mike Rhodes  Rodrigo Pinheiro de Lacerda 《Veterinary ophthalmology》2020,23(2):269-276

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