bluuebunny/crossref_metadata_2025 huggingface dataset:
Discriminação entre vozes adaptadas, levemente soprosas e tensas: diferenças entre os dois primeiros harmônicos
Authors: Cordeiro Gislaine Ferro , Cunha Maria Gabriela Bernardo da , Menezes Márcia Helena Moreira , Ubrig-Zancanella Maysa Tibério , Nemr Kátia
Published: July 2010

OBJETIVO: Verificar a eficácia dos valores da diferença entre os dois primeiros harmônicos para diferenciar vozes adaptadas de vozes levemente soprosas (B) ou tensas (S), durante a emissão da vogal "é" prolongada. MÉTODOS: Foram avaliadas 30 mulheres com vozes normais e alteradas. Foi gravada a vogal "é" de cada sujeito para posterior extração da intensidade dos dois primeiros harmônicos, por meio do gráfico FFT. Foi feita a subtração da amplitude do primeiro pelo segundo harmônico (H1-H2) e os dados foram tratados estatisticamente. RESULTADOS: A variação entre os valores de H1-H2, entre os sujeitos com grau 0 de soprosidade e tensão e os sujeitos com grau 1, também nos dois parâmetros, foi muito grande, portanto os valores não foram estatisticamente significativos. Entretanto, quando a soprosidade e tensão atingem o grau 2 a variação dos valores aproxima-se das descrições da literatura. CONCLUSÃO: A medida estudada não é eficaz para diferenciar vozes adaptadas daquelas levemente soprosas e tensas, em emissões da vogal "é" prolongada.
Correlação entre fechamento velofaríngeo e dimensões nasofaríngeas após cirurgia de retalho faríngeo avaliados por meio da técnica fluxo-pressão
Authors: Lanziani Flávia Fernandes , Yamashita Renata Paciello , Fukushiro Ana Paula , Trindade Inge Elly Kiemle
Published: July 2010

OBJETIVO: Verificar se a área dos orifícios velofaríngeos obtida após o retalho faríngeo (RF) durante a respiração de repouso (AVFr) é um indicador do grau de fechamento velofaríngeo durante a fala (AVFf). MÉTODOS: Os sujeitos foram 62 pacientes com fissura de palato, associada ou não à fissura de lábio, de ambos os gêneros, com idades entre seis e 32 anos, submetidos ao RF há, pelo menos, 12 meses. AVFr e AVFf foram determinadas por meio da técnica fluxo-pressão. Valores de AVFr inferiores a 0,500 cm² foram considerados subnormais. A AVFf foi classificada como adequada (0-0,049 cm²), marginal (0,050-0,199 cm²) ou inadequada (>0,200 cm²). A associação entre os valores de AVFr e AVFf pós-cirúrgicos foi analisada por meio de um modelo de regressão logística. RESULTADOS: Após o RF, 92% dos pacientes com valores de AVFr subnormais (<0,500 cm²) apresentaram fechamento velofaríngeo adequado. A proporção de pacientes com valores de AVFr normais (>0,500 cm²) e fechamento velofaríngeo adequado foi menor, porém ainda expressiva (55%). Não houve associação estatisticamente significante entre as duas variáveis. CONCLUSÃO: A maioria dos pacientes com retalho largo apresentou fechamento velofaríngeo adequado durante a fala. Entretanto, os resultados mostraram que as dimensões dos orifícios velofaríngeos durante a respiração de repouso não podem predizer a eficácia do retalho faríngeo para a fala.
Determinantes do grau de evidenciação de risco de crédito pelos bancos brasileiros
Authors: Dantas José Alves , Rodrigues Fernanda Fernandes , Rodrigues Jomar Miranda , Capelletto Lucio Rodrigues
Published: July 2010

Estudos que avaliam o nível de evidenciação praticado pelas organizações têm adquirido relevância na literatura contábil, na medida em que a evidenciação assume papel cada vez mais importante para a redução da assimetria de informação entre os diversos agentes econômicos. No caso do sistema financeiro, considerando suas peculiaridades, a transparência é essencial para garantir a confiabilidade e a estabilidade do sistema. O presente estudo teve por objetivo central avaliar o grau de transparência do risco de crédito praticado pelas instituições financeiras brasileiras, tendo por referência as divulgações qualitativas e quantitativas requeridas pelo Acordo de Basiléia II. Com base nas Informações Financeiras Trimestrais dos 50 maiores bancos, os resultados das análises revelaram, inicialmente, que o grau de evidenciação apresentou crescimento paulatino e constante no período, mas ainda atende a menos de 40% dos itens requeridos. Por meio de regressão, com o uso de dados em painel, foi constatado que o grau de evidenciação do risco de crédito de um período é explicado, inicialmente, pela divulgação do período anterior. Também foi constatado que o nível de evidenciação é explicado pela vigência de Basiléia II, pelo porte das instituições, pelo nível de rentabilidade, pelo índice de imobilização e pela listagem das ações na Bovespa.
O uso de quartis para a aplicação dos filtros de Graham na Bovespa (1998-2009)
Authors: Artuso Alysson Ramos , Chaves Neto Anselmo
Published: July 2010

Com o objetivo de avançar na compreensão do mercado acionário brasileiro e de analisar estratégias adequadas para o pequeno investidor, propõe-se uma análise da aplicação dos filtros de Graham para a seleção de ativos na Bovespa no período de 1998 a 2009. Mediante uma abordagem de carteira e de testes estatísticos, notou-se a presença de retornos anormais e superiores ao Ibovespa especialmente nas carteiras montadas por um período de cinco anos, entretanto as carteiras montadas possuíam baixa diversificação de ativos. Como os filtros de Graham foram desenvolvidos para o mercado norte-americano da década de 1970, sugeriu-se a elaboração de novos qualificadores de forma a adequá-los ao momento e ao cenário brasileiro. Essa abordagem usou os quartis mais interessantes de cada critério para definir os novos qualificadores e mostrou-se superior ao Ibovespa para todos os períodos analisados, mas não eliminou o problema de baixa diversificação dos portfólios.
O impacto da Lei Sarbanes-Oxley (SOX) na qualidade do lucro das empresas brasileiras que emitiram ADRs
Authors: Mendonça Mark Miranda de , Costa Fábio Moraes da , Galdi Fernando Caio , Funchal Bruno
Published: July 2010

Este trabalho objetiva analisar o impacto da Lei Sarbanes-Oxley (SOX) na qualidade do lucro das empresas brasileiras que emitiram ADR antes de 2002. Os escândalos contábeis de companhias como Enron e WorldCom reduziram a confiança dos investidores sobre a veracidade das demonstrações financeiras. A SOX surgiu com o propósito de proteger os investidores pela melhora na precisão e na confiabilidade na divulgação das demonstrações das empresas. Para medir a qualidade dos lucros, foram utilizados o Modelo de Basu (1997) e os modelos apresentados em Ball e Shivakumar (2005), estimados com dados em painel. Esperava-se que o aumento da regulamentação implicasse em maior grau de qualidade dos lucros nas empresas no período pós-SOX. Os resultados encontrados não são significativos nos modelos de Reversão à média das variações dos lucros e Cash Flow de Ball e Shivakumar (2005), mas os resultados do Modelo de Basu (1997) sugerem indício de aumento do conservadorismo contábil após a SOX, nas empresas brasileiras que emitiram ADR antes de 2002. Contudo, esse aumento do conservadorismo pelo Modelo de Basu (1997) também foi observado para todas as empresas brasileiras. Portanto, os resultados aqui apresentados sugerem indícios de aumento do conservadorismo brasileiro a partir de 2002, mas por outros motivos econômicos que não ocasionados pelo efeito SOX.
Goodwill: uma análise dos conceitos utilizados em trabalhos científicos
Authors: Martins Eliseu , Almeida Diana Lúcia de , Martins Eric Aversari , Costa Patrícia de Souza
Published: July 2010

A literatura contábil considera que o goodwill representa a diferença entre o valor da empresa e o seu patrimônio líquido avaliado a valores de mercado. A utilização de um conceito divergente desse, na elaboração de pesquisas teóricas ou empíricas, pode gerar resultados distorcidos, conclusões equivocadas, demonstrações financeiras apresentadas incorretamente, entre outros problemas de ordem teórica e prática. Nesse contexto, o objetivo do presente trabalho é verificar se o conceito de goodwill utilizado no desenvolvimento de pesquisas publicadas nos principais periódicos internacionais e nacionais, bem como na elaboração de dissertações e teses na área da contabilidade, é aquele referendado pela literatura contábil como correto. Por meio de análise de conteúdo, foram analisados 138 trabalhos científicos nacionais e internacionais, que contêm qualquer um dos seguintes termos no título, resumo ou palavras-chave: goodwill, intangible, intangibles, fundo de comércio, intangível e intangíveis. O total de trabalhos analisados está dividido em 60 trabalhos empíricos e 78 teóricos. Desse total geral de trabalhos, apenas 47 apresentam, explicitamente, o conceito de goodwill, sendo 24 empíricos e 23 teóricos. A maioria desses trabalhos que apresentam o conceito de goodwill o faz para discutir sobre tratamento contábil e avaliação de empresas. Do total de trabalhos com o conceito de goodwill explícito, 18 apresentam conceito divergente daquele definido pela literatura contábil. Os erros conceituais foram classificados em seis categorias, sendo que 61% deles se referem ao cálculo do goodwill como sendo a diferença entre o valor de mercado (somente calculado ou efetivamente pago) e o valor contábil do patrimônio.
Chill-induced changes in fatty acid composition of tonoplast vesicles from hypocotyls of Vigna unguiculata (L.) Walp.
Authors: Oliveira Luciana M. N. de , Sobreira Alana C. de M. , Monteiro Fernando de P. , Melo Dirce F. de
Published: July 2010

The present study was undertaken to investigate the changes induced by chilling on fatty acid composition of tonoplast vesicles from hypocotyls of Vigna unguiculata (L.) Walp. The 7 day-old control seedlings were grown at 25°C while treated seedlings were submitted to low temperatures (10°C and 4°C) for 4 days after 3 days germination. The chilling stress resulted in a differential inhibition of plant growth at 10°C and 4°C. Following chilling at 10°C and 4°C, the rate of unsaturated to saturated fatty acids increased under chilling stress. Our results suggest that the increase of unsaturated fatty acids content as well as the higher rate unsaturated/saturate fatty acidsmight be used by V. unguiculata plants as an adaptation mechanism likely to maintain the vacuolar membrane fluidity under low temperatures.
Experimental study on the setting time of cement paste mixed with accelerating admixtures based on C3A
Authors: Yi S.-T. , Heo G.
Published: July 2010

Setting time is a very important factor in terms of affecting the quality of tunnel lining and inclined slope strengthening. However, the quality criterion of the accelerating admixture (AA) used to improve setting time is not well established. In this study, methods of measuring the setting time of cement pastes with mixed AAs were evaluated using the Gillmore and Vicat needle test methods. It was found that for both test methods, regardless of initial and final setting, the setting time when the admixture was simultaneously added was faster than the post-addition method. For the Gillmore needle test method, two types of measurement methods were evaluated and it was observed that the setting time with cement type varied even when the same AA was used. Accordingly, manufacturing companies should develop AAs that are less influenced by cement type. For the Vicat needle test method, six types of measurement methods were evaluated and the following conclusions were obtained: (a) the temperature of materials should be controlled exactly and (b) to evaluate the performance of AA, an admixture usage of 5% (ratio of cement weight) was recommended.
Prediction of compressive strength of Portland cement paste based on electrical resistivity measurement
Authors: Wei X. , Tian K. , Xiao L.
Published: July 2010

Six cement pastes were prepared with two strength grades of cement and three water–cement ratios for electrical resistivity and compressive strength tests. The results from electrical resistivity measurement show that electrical resistivity values at 1 day and water–cement ratios follow a power function which is comparable with the relationship between compressive strength and water–cement ratio. A linear relation was established between the compressive strength at 2 days and the resistivity at 1 day, and a logarithmic relation was established between the compressive strength at 7 days or 28 days and the resistivity at 1 day. The quantitative relationships offer an alternative and non-destructive method to predict the compressive strength of pastes.
Microwave vitrification for lightweight aggregate manufacture
Authors: Robinson J. P. , Parry A. R. , Grenfell J. R. A. , Ghazireh N.
Published: July 2010

By-products of aggregate production, such as quarry fines, are a significant burden on the quarrying industry. This paper reports on an experimental study to manufacture lightweight aggregates, suitable for use in lightweight concrete building blocks, from fly ash and mixtures with quarry fines, by microwave heating. Material preparation and processing are described, along with their impact on yields of manufactured lightweight aggregates. Conventional lightweight aggregates include pumice and furnace bottom ash. Compared to these, based upon measurements of density and crushing strength, the manufactured aggregates would be suitable for use as aggregates in lightweight building blocks.
Chromosome Numbers and Microsporogenesis in Dallisgrass Paspalum Dilatatum Poir1
Authors: Bashaw E. C. , Forbes Ian
Published: July 2010

Synopsis

The common type of Paspalum dilatatum and a closely related yellow‐anthered type had 50 chromosomes. Meiosis I was characterized by 20 bivalents and 10 univalents which lagged at anaphase I. A semi‐prostrate, purple‐anthered type had 40 chromosomes and extreme meiotic irregularity, frequently having 20 laggards at anaphase I. A yellow‐anthered, erect type with pubescent spikelets had 40 chromosomes and regular meiotic behavior.
The Effect of Other Species and Mowing Height on Persistence of Lawn Grasses1
Authors: Davis R. R.
Published: July 2010

Synopsis

Bentgrass completely dominated mixtures in which it was seeded and spread into other plots. Merion bluegrass and red fescues were more resistant to invasion than common Kentucky bluegrass. Invasion occurred less at mowing height of 2 inches than at ¾ inch.
Inheritance of Resistance in Corn to Rust, Puccinia Sorghi Schw., and Genetic Relationships Among Different Sources of Resistance1
Authors: Russell W. A. , Hooker A. L.
Published: July 2010

Synopsis

Resistance was due to one dominant gene in each line. These are either in an allelic series or involve different loci that are closely linked.
Leaf Removal in Grain Sorghum. III. Main Culm‐Tiller Relationships1
Authors: Pauli A. W. , Stickler F. C.
Published: July 2010

Synopsis

Grain yields of main culms of 3 grain sorghum varieties were not significantly influenced by defoliating the tillers, and vice versa. Yield compensation for loss of leaf blade area was restricted to the defoliated culms.
Yields and Percentages of Crude Protein and Moisture of Several Annual Forage Crops as Affected by Harvest Date1
Authors: Wedin W. F.
Published: July 2010

Synopsis

Species exhibiting superior recovery capacity, rape and sudangrass, produced highest drymatter yields. Considering the first cutting only, differences in percent crude protein and dry‐matter yields among crops were highly significant (P=0.01). Harvestdate delay, studied over a 3‐week period, resulted in an approximate 340‐pound‐per‐acre dry matter increase to each percentage point decline in crude protein. Moisture percentages of early‐summer crops decreased more rapidly with advancing maturity than those of late‐summer crops.
Effects of Stand Reduction in Soybeans Simulating Three‐Cornered Alfalfa Hopper Injury1
Authors: Caviness C. E. , Miner F. D.
Published: July 2010

Synopsis

Reductions in yield due to 3 rates of plant removal (15, 30, and 45%) at 3 stages of plant growth were relatively small. Greatest reduction in yield occurred when plants were removed about 2 weeks after bloom with progressively less reduction being evident at the peak blooming period and about 2 weeks before bloom! An increased number of pods per plant appeared to be the component of yield primarily responsible for this compensation.
Yield and Persistence of Several Legume‐Grass Mixtures as Affected by Cutting Frequency and Nitrogen Fertilization1
Authors: Wolf Dale D. , Smith Dale
Published: July 2010

Synopsis

Mixtures containing alfalfa and orchard‐grass were the highest yielding. Mixtures cut 3 times produced higher yields than those cut 5 times. Yields from 5 cuttings were increased more by nitrogen than yields from 3 cuttings. Nitrogen had no influence on yields of alfalfa mixtures cut 3 times, but increased those cut 5 times. Birdsfoot trefoil and ladino clover mixtures were predominately grass, especially when nitrogen was applied.
Effect of Soil Actinomycetes on Strains of Rhizobium japonicum1
Authors: Damirgi Salih M. , Johnson Herbert W.
Published: July 2010

Twenty‐four isolates of Actinomycetes were taken from soil of an experimental soybean field. Susceptibility of eight Rhizobium japonicum strains to antimicrobial action of the Actinomycete isolates on yeast extractmannitol agar was tested. Twenty of the isolates produced no inhibition of rhizobia. Isolate E1 antagonized only R. japonicum strain 76 and isolate E8 was antagonistic to all strains. Two other isolates showed slight inhibition of strains 122 and 123.

Infectivity of rhizobia on soybean variety Kent was evaluated in the presence of selected Actinomycete isolates. In autoclaved soil, reductions in nodule numbers produced by rhizobial strains were 35% and 53%, when Actinomycete E8 was introduced into the soil at the time of planting and 28 days before planting, respectively. Generally, similar results were obtained in sterilized sand jars.

The results suggest that anti‐rhizobial soil microorganisms in a particular soil play a role in the establishment of specific rhizobial strains.
Nitrogen Effect on Leaf Area, Yield, and Nitrogen Uptake of Barley under Moisture Stress1
Authors: Luebs R. E. , Laag A. E.
Published: July 2010

Two nitrogen and two moisture levels were combined in 4 treatments to study nitrogen and moisture effects on barley grown under moisture stress conditions. Nitrogen was applied at 17 and 68 kg/ha and moisture levels differed by 3.7 surface cm at heading. The higher nitrogen level increased dry matter production during the vegetative growth period. Green leaf area (both sides) reached a maximum of 4.8 times the land area at late jointing and decreased because of moisture stress thereafter. Green leaf area was higher for over a month between late jointing and the soft dough stage with higher nitrogen. This greater transpiring area is suggested as the cause for grain yield decreases with more nitrogen. Increased moisture stress with higher nitrogen was indicated by decreased green to necrotic leaf weight ratios and greater straw to grain weight ratios.

Additional applied nitrogen was reflected in increased uptake of nitrogen. However, for a given nitrogen level, nitrogen content was higher at the lower moisture level.

The additional 3.7 cm of water at heading increased average barley grain yield 560 kg/ha and increased moisture use efficiency up to 23.3 kg per hectare‐centimeter of water for the growing season.
Castorbean Production as Related to Length of Growing Season. II. Date of Planting Tests1
Authors: Kittock D. L. , Williams J. H.
Published: July 2010

Yield of irrigated castorbeans (Ricinus communis L.) in Nebraska was highest when planted the first 2 weeks of May, particularly when Alternaria leaf spot [Alternaria ricini (Yoshii) Hansford] was not a factor in the results. for nonirrigated castorbeans there was little difference in yield for any May plantings. April and June plantings were lower in yield. The time required for emergence was correlated with soil temperature and decreased with later plantings. Total emergence increased from 55% for March planting to 75% for June plantings. Lodging was inversely correlated with hypocotyl diameter within but not between varieties. Weight per 100 seeds in most cases was highest for primary racemes and progressively lower for secondary, tertiary, and quaternary racemes. Seed from racemes, particularly tertiary and quaternary, rapidly decreased in weight with later plantings. A positive and significant correlation coefficient of 0.88 was found between weight per 100 seeds and germination percentage. Seeds from earlier planting dates tend to have higher germination.
Relationship of Temperature to the Development of Calcium Deficiency Symptoms in Nicotiana tabacum1
Authors: Chang S. Y. , Lowe R. H. , Hiatt A. J.
Published: July 2010

Tobacco (Nicotiana tabacum L.) was grown in controlled environmental growth chambers at five different temperatures (21, 23, 26, 29, and 30 C) in two separate experiments. Plants grown at 21 and 23 C developed no Ca deficiency symptoms, and only a few plants of genetically susceptible varieties (‘Burley 21’ and Ky Exp 22) developed Ca deficiency symptoms when grown at 26 C. However, these varieties developed very severe Ca deficiency symptoms when grown at either 29 or 30 C. ‘Ky 16’ (nonsusceptible) and ‘Ky 12’ (slightly susceptible) developed slight and severe deficiency symptoms at 29 C. These two varieties were grown only at the 23 and 29 C temperatures.

A moderately deficient level of K (0.6 meq/liter) resulted in appreciably less severe development of Ca deficiency symptoms. Differences due to K were slight or not apparent at higher levels of K concentration in the nutrient solutions. However, increasing the level of K nutrition resulted in a decrease in Ca content at all levels of K used.

An increase in temperature at which the plants were grown resulted in an increase in Ca accumulation in the stems. Apparently the Ca is being immobilized in the stems at higher temperatures and is failing to reach the meristem and terminal leaves, the critical portion of the plant with respect to Ca deficiency.
Moisture Equilibrium Values for Several Grass and Legume Seeds1
Authors: Harrington James F.
Published: July 2010

The equilibrium moisture contents of seeds of 35 kinds of grasses and legumes were determined for the seed moisture range of 13 to 4%. In comparison with the mean equilibrium moisture values of all seeds tested, the correlation coefficients for every kind of seed tested are highly significant, with r values of .95 to .99. This shows that although a given kind of seed may have a higher or lower moisture content than another kind at a given relative humidity, all kinds of seed tested showed essentially parallel changes in moisture content with changes in relative humidity, at least in the seed moisture range of 13 to 4%. A method is given for using the data presented in forecasting the equilibrium moisture percentage that each kind of seed will reach in a mixture of seeds in a sealed container.
Root and Foliage Growth of Oats at Several Levels of Fertility and Moisture1
Authors: McNeill M. J. , Frey K. J.
Published: July 2010

The effects of fertility and moisture on root and shoot gorwth of oats (Avena sativa L.) were studied in potculture experiments. An experimental unit was a 75‐liter garbage can filled with low‐fertility Thurman sand, embedded 0.6 m deep in the soil. Forty‐eight can were covered with a plastic shelter to permit controlled moisture regimes. A factorial set of fertilizer treatments using two levels each of N (0 and 140 kg/ha), P (0 and kg/ha), and K (0 and 93 kg/ha) were applied at seeding time. At the initiation of stem elongation, wet (field capacity) and dry (wilting coefficient) moisture regimes were imposed across all fertility treatments.

Traits measured on the plant tops were plant height, number of tillers, number of spikelets per panicle, dry weight and stem diameter. Weights were taken on roots extracted from 0.007‐m3 soil samples from the 0‐15‐, 15‐30‐, 30‐45‐, and 45‐60‐cm soil depths.

The root and shoot growth responded more to fertilizer application when moisture was adequate than when deficient. Nitrogen and phosphorus, applied alone and in combination, gave more shoot and root growth than any other element or combination of elements. Shoot growth responded to added fertilizer in both the high and low moisture regimes, but root growth responded only in the wet regime. Leaching of the nutrients with surface irrigations caused maximum root response to N in the 30‐45‐ cm zone, but for P, which resists leaching, maximum response was in the 0‐15‐cm zone. Reduced root‐top ratios resulting from added moisture and fertilizer elements were due largely to large increases in top growth without concomitant increases in root growth.

Increase in shoot weight from added fertilizer under the dry regime was not accompanied by increased root weight. We concluded that root response to added fertility could not be responsible for oat plants utilizing subsoil (30‐60‐cm depth) moisture to produce increased shoot weights.
Fertilizer Placement with Sodding1
Authors: Foote L. E.
Published: July 2010

Sod knit was significantly increased by fertilization. Tilling fertilizer into the soil prior to sod placement had no effect. The best fertilizer placement seemed to be one‐half under and one‐half over the sod. A useful mechanism for mechanically measuring sod knit is described. Other methods of measuring sod knit and fertilizer effect were not successful.
Resistance of Certain Grain Sorghum Hybrids to Bird Damage in Louisiana1
Authors: Tipton K. W. , Floyd E. H. , Marshall J. G. , McDevitt J. B.
Published: July 2010

Several grain sorghum hybrids were evaluated for resistance to bird damage at Baton Rouge, Alexandria, and St. Joseph La. Most of the damage was done by the English sparrow during the milk stage of seed development. Loss from damage by birds varied from less than 1% to as great as 80% seed loss. Approximately onehalf the hybrids tested exhibited considerable resistance to birds. Bird feeding on grain sorghum in the field continued on a limited scale until the crop was harvested. During the milk stage of seed development, the bird crushed or mashed the juices from the seed. After hardening, the seed was removed from the plant and swallowed whole. Chemical analyses of developing grain of susceptible and resistant hybrids showed that the contents of tannic acid and total astringents of a resistant hybrid were approximately eight and four times, respectively, greater than that of two susceptible hybrids. Content of tannic acid and total astringents did not change with seed maturity.
Effect of 2‐Chloroethylphosphonic Acid on Vegetative Development and Seed Yield of Castor (Ricinus Communis L.)1
Authors: Stafford R. E.
Published: July 2010

The compound, 2‐chloroethylphosphonic acid (formerly referred to as 2‐chloroethanephosphonic acid), sprayed on plants of two normal‐monoecious castor (Ricinus communis L.) varieties significantly increased node number to first raceme and significantly reduced seed yield and bushel weight. Mature plant height, weight per 100 seeds, and oil percentage were not significantly affected. No apparent increase in number of pistillate flowers on either variety was noted.
Periodic Changes in the Ionic Concentrations of Some Submerged Soils of Bihar1
Authors: Biswas D , Naphade J. D. , Dhua S. P.
Published: July 2010

The investigation was carried out under laboratory conditions to study the chemistry of submerged soils of Bihar to help in assessing their potentialities in meeting the nutritional requirements of the rice plant (Oryza sativa L.). The soils were kept at 1:1.5 soil:water ratio and analyzed periodically for pH, electrical conductivity, soluble NH4+, Fe++, Mn++, P, Na+ K+, Ca++, CO3=, HCO3−, and Cl− on the 15th, 30th, 45th, and 60th day. The results show differential release of these nutrients in different soils with time. While the pH of acidic soils increased, that of alkaline soils decreased with the time of submergence. The pH of all soils fell between 6.50 and 8.50 on the 60th day. In general the peak values of Mn++ and CO3 = were noted on the 15th day, HCO3− and Cl− on the 30th day, and that of NH4+ between the 30th and 45th day after submergence. Most of the soils appear to be inherently deficient in N, P, K, Fe++ etc. and a good response of rice to fertilizer applications may be expected.
Crop Response to Phosphate Fertilization and to Residual Phosphate Levels: I. Field Experiments1
Authors: Giskin M. , Hagin J. , Kafkafi U.
Published: July 2010

Intensive phosphate fertilization practices over the last two decades have resulted in large quantities of phosphates accumulating in soils. The objective of two field experiments was to evaluate yield response to various levels of residual phosphorus.

The experiments were carried out within an irrigated rotation having two crops per year. The initial experimental treatments consisted of four rates of superphosphate equivalent to 0, 48, 144, and 432 kg P/ha, applied prior to each of three crops. Following the harvest of the third crop the original plots were quartered and six additional crops were grown on each of the two soils. Superphosphate was added before the seeding of each crop in amounts equal to 0, 13, 26, and 52 kg P/ha.

Out of the 18 crops harvested, there were only four yield responses to P fertilization significant at either the 0.05 or 0.01 level. The high initial residual P level (10‐11 ppm NaHCO3‐soluble P) and the low P fixing power of the soils (68 and 75% of the added P remained exchangeable) could explain the low frequency of response to phosphate fertilization. It was only after five to six successive crops were grown, that the bicarbonate‐soluble P in the control plots dropped below 8 ppm. In these cases plant response to residual P was found. Accepted agronomic fertilizer rates (13 to 52 kg P/ha) applied to crops 4 to 9 were capable of maintaining soil residual P levels between 6.3 and 17.5 ppm P (NaHCO3‐soluble). At residual P levels of 26.2 to 97.5 ppm P (NaHCO3‐soluble) similar fertilizer rates were not capable of maintaining or recharging the soil “phosphate pool” which had been achieved by the heavy fertilizations (48 to 432 kg P/ha) applied to crops 1 to 3.
Oxygen Diffusion in the Soil‐Plant System V. Oxygen Concentration and Temperature Effects on Oxygen Relations Predicted for Maize Roots1
Authors: Luxmoore R. J. , Stolzy L. H.
Published: July 2010

A model for steady state isothermal oxygen diffusion into a cylindrical root surrounded by a uniform water film, accounting for longitudinal oxygen flux through intercellular gas spaces, radial flux through the water film, and a concentration‐dependent respiratory oxygen sink, was used to assess effects of change in soil and root oxygen concentration and temperature on the oxygen relations of maize (Zea mays L.) roots.

Increases in both root oxygen concentration at 5 cm from the tip and in soil oxygen concentration increased the root oxygen profile. Under conditions of high soil oxygen concentration and low root concentration oxygen diffused back along the root toward the shoot. Change in root oxygen concentration (0.05 to 0.15 ml/ml) at cm from the root tip had only a small effect on the oxygen concentration at the root tip, whereas an increase in soil oxygen concentration (0.05 to 0.15 ml/ml) increased the root tip oxygen concentration (0.02 to 0.07 ml/ml). Respiration rate of the root tip (1‐mm section) was closely dependent on soil oxygen supply and plant aeration had very little effect. Plant aeration contributed significantly to the respiration rate on a whole‐root basis. Mean root respiration rate increased with increase in soil and root oxygen concentration and also with increase in temperature. The root oxygen concentration profile decreased with rise in temperature associated with an increased respiratory oxygen demand. For mean respiration rate Q10 was less than 2 and decreased with increase in temperature.
Comparison of Heavily Fertilized Pangolagrass and Stargrass Pastures under Humid Tropical Conditions1
Authors: Caro‐Costas Rubén R. , Abruña Fernando , Vicente‐Chandler José
Published: July 2010

There is little information on the comparative productivity of intensively managed pastures of pangolagrass (Digitaria decumbens) and stargrass (Cynodon Niem fuensis) under humid tropical conditions.

Therefore, an experiment was conducted to compare the productivity of these grasses growing on a steep ultisol when fertilized with 2.2 metric tons of 14‐4‐10/ha yearly and grazed by young cattle over a 2‐year period in the humid tropics of Puerto Rico.

Stargrass produced 1,514 kg/ha of beef yearly with daily gains of 0.60 kg per head, compared with 1,062 kg/ha of beef and daily gains of 0.49 kg per head for pangolagrass. Stargrass had a carrying capacity of 7.4 steers (275 kg)/ha compared to 6.5 for pangolagrass. Throughout the year, stargrass had higher dry matter and protein contents (ranging from 11.3 to 19.6%) than pangolagrass.
Phosphorus Utilization by Flax, Wheat, Rape, and Buckwheat from a Band or Pellet‐like Application. I. Reaction Zone Root Proliferation1
Authors: Strong W. M. , Soper R. J.
Published: July 2010

To explain the large variability among crops in their utilization of P from band or pellet‐like applications, the recovery of 32P‐labelled dicalcium phosphate dihydrate (DCPD) from a simulated phosphate fertilizer reaction zone was studied in a pot experiment with four crops, flax (Linum usitatissimum L., cv. Redwood), wheat (Triticum vulgare L., cv. ‘Manitou’), rape (Brassica napus L., ‘Tanka’), and buckwheat (Fagopyrum escutentum Moench). Attention was focused on the portion of the root system which feeds on the applied P. Reaction zone root development was quantified by confining the spread of applied P to a small, easily recoverable portion of the soil mass in the pot. Root systems of the four crops proliferated within this simulated phosphate reaction zone, each to a varying degree. In increasing order of reaction zone root proliferation, the crops ranked as follows: flax, wheat, buckwheat, and rape.

The influence of root development within the fertilizer reaction zone on applied P utilization was assessed for these four crops by comparing crop utilization of applied P from two systems each fertilized with a simulated fertilizer reaction zone containing 32P‐labelled DCPD. In one system the reaction zone was positioned at the center of the soil mass within the pot. In the other, a greater opportunity was afforded the root system to develop within the reaction zone by so positioning the reaction zone that the entire root mass passed through it. Recovery of labelled P from these contrasting pot shapes indicated that the proportion of the root system which feeds within the reaction zone as well as the opportunity given it to absorb applied P has direct bearing on crop recovery of band applied phosphatic fertilizer.
Screening of Rice Cultivars for Tolerance to Al‐toxicity in Nutrient Solutions as Compared with a Field Screening Method1
Authors: Howeler R. H. , Cadavid L. F.
Published: July 2010

Upland rice (Oryza sativa L.) grown on acid soils may suffer serious yield reductions due to Al‐toxicity. Field experiments showed that many tall traditional cultivars from acid soil areas required only small lime applications, while most of the new semi‐dwarf cultivars required substantial quantities of lime to reach their yield potential. Without or with modest applications of lime, the tall Al‐tolerant cultivars consistently outyielded the Al‐susceptible semi‐dwarf cultivars. Since high lime applications are often prohibitively costly and difficult to incorporate deeply, Al tolerance can be an important characteristic for upland rice cultivars.

Large numbers of rice cultivars were screened in the field for AI tolerance at several lime levels. A more rapid nutrient solution screening method for rice seedlings was developed. The relative rootlengths (RRL) of plants grown at 30 and 3 ppm AI was used as an index of AI tolerance. The RRL values of eight cultivars used as standards corresponded to field observations of their relative tolerance to acid soils. Moreover, the RRL values of 240 cultivars were well correlated with grain yields in the field, obtained at a low lime level.
Leaf, Petiole, and Stem Accumulation, and Digestibility in ‘Amclo’ Clover1
Authors: Beaty E. R. , Smith Albert E. , Powell John D.
Published: July 2010

The South has long needed a high yielding legume to complement the perennial grasses of the region. ‘Amclo’ arrowleaf clover (Trifolium vesiculosum Savi) released in 1963 is high yielding and the forage is high in quality, but management required to maintain the high quality in the harvested feed is not known. We wanted to know the dry matter accumulation rate and digestibility during the active growth period. In 1973 and 1974, we measured dry matter accumulation and digestibility of leaves, stems, petioles and flowers of field grown volunteer stands of Amclo clover growing on Orangeburg loamy sand, a silicous thermic typic Paleudult by harvesting a new plot each week from January or February until June. The plant samples were separated into plant parts, dried, ground, and analyzed for in vitro digestible dry matter weekly throughout the experiment.

By mid‐March leaflet and petiole production had maximized at 3,500 to 4,000 kg/dm/ha. Stem growth was active during April and by 2 May stem yield was approximately 6,000 kg/ha. During May stem growth slowed and flowering was active. Flower production averaged approximately 2,000 kg/ha. In vitro dry matter digestibility averaged 69% for leaves and 73% for petioles while stem digestibility dropped from 73% in March to 51% in June.

Leaf N averaged 5.5% until mid‐April and fell to 3.2% in June. Petiole N averaged approximately 2% throughout the growth period and stem N was high in March but decreased rapidly in late April and May. By 6 June stem N was approximately 1%.

Total forage N increased from 59 kg/ha in early February to 232 kg/ha on 11 April and remained constant at that level during May and into June.

The arrowleaf clovers are growing in importance for both grazing and harvested feed. Value for each is related to the mix of leaves, petioles, and stems. This research shows the ratio and IVDMD of each over the life of the plant. The arrowleaf clovers are being used for grazing, hay, industrial forage, and silage over a wide range of uses and these data are expected to be widely used in making more effective management time of harvest decisions.
Forage Establishment in Wheat Stubble
Authors: Olsen F. J. , Jones J. H. , Faix J. J.
Published: July 2010

The establishment of forages using wheat (Triticum aestivum L.) as a companion crop has been unreliable in recent years because of competition for light and moisture by vigorous, high‐yielding, modern wheat cultivars. This field study was conducted during 1975–77 to assess the feasibility of establishing forages in late summer in wheat stubble grown on a fine‐silty, mixed, mesic Aquic Hapluadolf soil using different tillage systems and seeding implements. Tillage systems used included conventional, disk, and no‐till. The Allis‐Chaimers No‐Till planter, Brillion seeder, International Harvester grain drill, John Deere Model 1500 Powr‐till drill, and Zip seeder were employed to determine the possibility of obtaining acceptable stands of Ladino clover (Trifolium repens L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Forages were successfully established in wheat stubble without tillage using the Allis‐Chalmers No‐Till planter and John Deere Model 1500 Powr‐till drill. Satisfactory forage stands were obtained using the Brillion seeder and International Harvester grain drill in disked wheat residue and a conventionally prepared seedbed. The Zip seeder did not operate satisfactorily in wheat stubble in this study. Planting forages in wheat stubble enhanced winter cover, providing soil protection from erosion.
Salt Tolerance of Australian Channel Millet1
Authors: Shannon M. C. , Wheeler E. L. , Saunders R. M.
Published: July 2010

Undomesticated plant species may be a valuable resource for increasing crop diversity and developing crops for use in semiarid and saline areas. Australian channel millet (Echinochloa turnerana (Domin) J. M. Black) is very drought tolerant; however, its salt tolerance has not been tested. In drum culture studies, conducted in the greenhouse, plant height, weight, and seed grain weight were measured as a function of saline stress. Concentrations of Na, Ca, and Cl in leaves and stems increased as soil salinity increased. At salinities above 1.5 S m−1, E. turnerana is as salt tolerant as bermudagrass (Cynodon dactylon L.). The grain yield by E. turnerana was decreased by 50% by 2.4 S m−1 salinity; whereas, previous studies have shown that proportionate grain yield reductions of sorghum [Sorghum bicolor (L.) Moench] and barley (Hordeum vulgare L.) occur at 1.1 and 1.8 S m−1, respectively. E. Turnerana has high salt tolerance as either a grain or forage crop, and as a forage displays superior digestibility. This species could be exploited for future use on marginal lands.
Compensatory Response of Sunflower to Stand Reduction Applied at Different Plant Growth Stages1
Authors: Miller J. F. , Roath W. W.
Published: July 2010

Differential plant populations occurring among plots in yield trials can be critical in evaluating potential worth of sunflower (Helianthus annuus L.) hybrids or breeding lines. The objective of this study was to determine degree of loss in seed yield when stand is reduced at various growth stages of plant development and to identify the nature of plant compensation for stand loss in sunflower.

No significant reductions in seed yield occurred when plant populations were reduced 25% from the check (50,000 plants/ha) at the 4, 8, and 16‐leaf growth stages. Compensation was due to significant increases in head diameter. Stand loss of 25% at later growth stages resulted in significant yield loss. Compensation occurred in seed weight as well as head diameter when stands were reduced 50% at early growth stages. Seed yields were reduced 18 to 23%.

Sunflower plants were able to significantly compensate even when 75% stand reduction was applied at bud and flowering stages, with seed weight accounting for most recovery in yield. A 38 to 42% and 56 to 58% loss occurred when stands were reduced 75% at the 4 to 16‐leaf and bud to flowering growth stages, respectively. Oil percentages of seeds from plants grown in plots with high stand reductions were reduced 6% and height was decreased 25 cm. Significant negative correlations were noted between oil percentage and height with yield, head diameter, and seed weight at the lowest plant population. Plant population would be critical to control in studies investigating inheritance of plant height or oil percentage of sunflower.
Warm‐season Grass Establishment with Atrazine1
Authors: Martin A. R. , Moomaw R. S. , Vogel K. P.
Published: July 2010

Weed competition is a limiting factor in warm‐season grass establishment often delaying the first forage harvest 2 or 3 years. Weed control with herbicides could reduce this competition resulting in more rapid grass establishment. Field experiments were conducted to evaluate the effect of atrazine [2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine] on weed control, warm‐season grass establishment, and forage yield during the seeding and following year.

Several warm‐season grass species were spring seeded at locations having distinctly different soils. The soils involved were a Butler silty clay loam (Abruptic Argiaquoll) containing 3.8% organic matter and a pH of 5.2, a Crofton silty clay loam (Typic Ustorthent) containing 2.1% organic matter with a pH of 7.2 and a Nora silty clay loam (Udic Haplustoll) containing 2.8% organic matter and pH 5.8. Atrazine at various rates was applied preemergence shortly after grass seeding and at one site it was atso applied the preceding fall. Weed control, grass establishment, and forage yield were measured the year of seeding and the following year.

Uncontrolled weeds during the year of seeding reduced stands and 1st year forage yields of big bluestem (Andropogon gerardi Vitman), indiangrass [Sorghastrum nutans (L.) Nash], sand lovegrass [Eragrostis trichodes (Nutt.) Wood], sideoats grama [Bouteloua curtipendula (Michx.) Torr.], and switchgrass (Panicum virgatum L.). Big bluestem and switchgrass tolerated preemergence atrazine applications of 3.4 kg/ha on the Butler soil. Big bluestem was less tolerant of atrazine than switchgrass on the Crofton soil. Some atrazine tolerance was present in indiangrass but not in sand lovegrass and sideoats grama. Seeding year forage yields of big bluestem and switchgrass were significantly increased by atrazine. Weed control during the seeding year sometimes resulted in higher forage yields the following year. Big bluestem and switchgrass can he readily established and produce substantial forage yields the year of seeding by using atrazine for weed control. This would make these grasses more attractive to farmers and ranchers.
A Field Study of Plant Resistance to Water Flow in Alfalfa1
Authors: Abdul‐Jabbar A. S. , Lugg D. G. , Sammis T. W. , Gay L. W.
Published: July 2010

The objective of this study was to investigate the plant resistance to water flow (Rp) in alfalfa (Medicago sativaL.) under field conditions. Plant resistance was computed using Ohm's law analog from leaf water potential (ψ1), transpiration rate (T), soil resistance (Rs), and soil water potential (ψs). A pressure chamber was used to measure ix hourly throughout the 3 days, 18, 19, and 20 Aug. 1982. Evapotranspiration rate (ET) was measured continuously using the energy balance‐Bowen ratio method, and T was assumed to equal ET because the alfalfa completely covered the soil, thus limiting evaporation from the soil. The leaf area index was 4.3. Soil resistance was computed from root radius and root length density data, and had a value of 698 h, which was much smaller than the calculated value of (Rp). Soil water potential was calculated from soil moisture content data obtained using a neutron probe. Using this approach, Rpwas almost constant throughout the day from 0730 to 1500 h, with an average value of 1.97 × l05h. From 0730 to 1500 h, (Rp) was not significantly correlated (P<0.05) with the water potential gradient (ψ1−ψs) (r=0.08). In addition, & was not significantly correlated with values of T above 0.2 mm/h (r= −0.32). Plant resistance to water flow in alfalfa was similar to reported values for other crops.
Structural Polysaccharides in Forages and Their Degradability
Authors: Hatfield R.D.
Published: July 2010

Plant cell walls are organized into complex matrices composed primarily of carbohydrates that represent a potential energy source for ruminants. An overview of the basic structural features of the major groups of polysaccharides that make up forage cell walls, metabolic changes during cell wall development, cell wall component interactions, and some aspects of cell wall degradation are presented. Polysaccharide components that compose the cell wall matrix can be disassociated and fractionated according to similar physio‐chemical properties. Plant structural polysaccharides vary in monosaccharide composition, substitution patterns, and glycosidic linkages between monomers. Chemical fractionation schemes typically separate structural polysaccharides into three major groups. These include pectic polysaccharides rich in galacturonic acid residues, hemicellulosic polysaccharides typically rich in xylose, and the cellulose fraction. Mature walls can be envisioned as a layered matrix with cellulose microfibrils embedded in an amorphous material composed of pectic and hemicellulosic polysaccharides. The amorphous regions of cell walls show the greatest variation during development. Interactions among individual components of the cell wall are key to the formation and structural integrity of the matrix. These include bonding interactions that range from weak hydrogen bonds to covalent cross‐links. During growth of plant cells there is a rearrangement of structural elements within the wall. The matrix undergoes reorganization by disruption of selected intra‐ and intermolecular bonds and de novo synthesis and insertion of new wall polymers. Individual polysaccharides may vary in rates and possibly extent of degradation by rumen microorganisms. These differences are due to the degree of hydrogen bonding of the individual polysaccharides, branching patterns, and associations with other wall constituents.