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Search Results: 1 - 10 of 18611 matches for " Hans Raj;Soares "
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Produ??o de girassol sob estresse salino e aduba??o nitrogenada
Nobre, Reginaldo Gomes;Gheyi, Hans Raj;Soares, Frederico Antonio Loureiro;Cardoso, José Alberto Ferreira;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000300027
Abstract: the limited availability of low-salinity water in brazilian semiarid region causes producers to use water of moderate to high salinity for irrigation. in view of the increasing importance of sunflower (helianthus annuus l.) in this region as a potential source of renewable energy, this study was conducted to evaluate sunflower crops irrigated with different water salinity levels (ecw) and fertilized with nitrogen. the experiment was conducted in a greenhouse of the federal university of campina grande (ufcg), from july to october 2009, in a randomized block design, to test five ecw levels (0.5 - control, 1.6, 2.7, 3.8, and 4.9 ds m-1) and four n rates (50, 75, 100 and 125 % of the rate recommended for pot experiments) in a 5 x 4 factorial scheme, with three replications. the salinity of irrigation water and nitrogen fertilization affected the sunflower plants in independent ways. water salinity affected the leaf area, biomass of aerial parts and roots, weight and total production of achenes and harvest index linearly and negatively. higher n rates on the other hand reduce the crop cycle and period from achene formation to physiologic maturity, and increased its mass.
Crescimento de híbridos e variedades porta-enxerto de citros sob salinidade = Growth of hybrids and rootstock varieties of citrus under salinity.
Pedro Dantas Fernandes,Marcos Eric Barbosa Brito,Hans Raj Gheyi,Walter dos Santos Soares Filho
Acta Scientiarum : Agronomy , 2011,
Abstract: A salinidade da água e do solo afeta o crescimento, o desenvolvimento e a produ o de espécies frutíferas, dentre as quais os citros. O uso de porta-enxertos tolerantes pode garantir a sustentabilidade do agronegócio citrícola em tais condi es. Assim, estudou-se a sensibilidade à salinidade durante a fase de forma o de portaenxertoscompreendendo variedades e híbridos selecionados. O experimento foirealizado em casa-de-vegeta o, considerando cinco níveis de salinidade da água de irriga o [testemunha, irriga o com água de abastecimento local, condutividade elétrica da água (CEa) de 0,41 dS m-1 e água com CEa de 1,0; 2,0; 3,0 e 4,0 dS m-1] e sete genótipos, utilizando delineamento em blocos casualizados, com cinco repeti esem esquema fatorial e quatro plantas úteis por parcela, durante o período de 150 dias. Avaliaram-se variáveis de crescimento e fisiológicas. A redu o mais expressiva foi observada na fitomassa seca total da parte aérea com aumento unitário da CEa. Observou-se redu o linear no crescimento com aumento da salinidade nos híbridosLVK x LVA-009 e TSK x TRENG-256. Dentre os genótipos avaliados, o limoeiro ‘Volkameriano’ foi o menos sensível ao estresse salino. Water and soil salinity affects the growth, development and production of fructiferous species, such as citrus. The use of tolerant rootstocks can guarantee the agribusiness of citrus under such conditions. Thus, the sensibility to salinity during the phase of rootstock formation of varieties and selected hybrids was studied. The experiment was carried out in a greenhouse, with five levels of irrigation water salinity [control, tap water with electrical conductivity (ECw) of 0.41 dS m-1, and water with ECw of 1.0, 2.0, 3.0 and 4.0 dS m-1] and seven genotypes, in a randomized block designand five replications each consisting of four plants, during 150 day period. Growth and physiologic variables were evaluated. Significant effects of genotypes and salinity in the variables were observed. The most expressive reduction was found for total dry matter with unit increase of ECw. A linear reduction was observed in hybrids LVK x LVA-009 and TSK x TRENG-256. Among the evaluated genotypes ‘Volkamer’ lemon was the least sensitive to saline stress.
Crescimento e Produ o de Flores de Girassol Irrigado com água Salobra
Kaline Dantas Travassos,Frederico Antonio Loureiro Soares,Hans Raj Gheyi,Nildo da Silva Dias
Revista Brasileira de Agricultura Irrigada , 2011, DOI: 10.7127/rbai.v5n200036
Abstract: Nos últimos anos, devido ao aumento de produ o de espécies ornamentais no Brasil e no mundo, o girassol também ganhou destaque como planta ornamental. Este trabalho teve como objetivo verificar os efeitos da salinidade da água de irriga o no crescimento e na produ o de flores do girassol (Helianthus annuus L., cv. Embrapa 122-V2000) através das variáveis diametro externo do capítulo, início do florescimento, dura o de pós colheita, número de pétalas no capítulo para fins ornamentais. Os tratamentos foram compostos de seis níveis de salinidade da água de irriga o (CEa ) de 0,5; 1,0; 2,0; 3,0; 4,0 e 5,0 dS m-1 à 25 oC, em delineamento inteiramente casualisado com 10 repeti es por tratamentos. O número de pétalas no capítulo diminuiu significativamente com o aumento da salinidade da água de irriga o, sendo as plantas irrigadas com água de baixa (0,5 dS m-1) e alta salinidade (5 dS m-1) apresentando 27,8 e 17,5 pétalas, respectivamente. O diametro externo médio do capítulo para as plantas irrigadas com água de baixa e alta salinidade foram de 17,5 e 14,3 cm, respectivamente. O decréscimo de fitomassa seca da parte aérea das plantas de girassol foi de 12,8% por aumento unitário da salinidade da água, confirmando a tolerancia do girassol à salinidade. é possível produzir flores de girassol com água de salinidade até CEa de 5,0 dS m-1 sem afetar qualidade comercial.
Salinidade da água de Irriga o na Aclimatiza o de Mudas, Desenvolvimento e Produ o de Heliconias
Antonio Evami Cavalcante Sousa,Frederico Antonio Loureiro Soares,Hans Raj Gheyi,Helder Morais Mendes Barros
Revista Brasileira de Agricultura Irrigada , 2011, DOI: 10.7127/rbai.v5n400067
Abstract: A utiliza o de águas com altos níveis de condutividade elétrica comumente encontrados no final do período de estiagem, trás sérios riscos de saliniza o para os solos a serem irrigados, causando prejuízos, para as culturas. O objetivo deste trabalho foi avaliar os efeitos da salinidade da água de irriga o sobre aclimatiza o de mudas, crescimento, desenvolvimento e produ o de seis genótipos de heliconias. O experimento foi conduzido em casa de vegeta o, município de Campina Grande-PB. A pesquisa foi realizada em duas etapas, sendo a primeira utilizando seis níveis de condutividades da água de irriga o CEa (0,3; 0,8; 1,3; 1,8; 2,3 e 2,8 dS m-1) e seis genótipos de heliconias, compondo um esquema fatorial (6 x 6). Para a segunda etapa observou-se, três níveis (CEa de 0,8; 1,8; e 2,8 dS m-1) em dois tipos de forma es de mudas de seis genótipos de heliconias compondo esquema fatorial triplo (3 x 2 x 6), ambos em delineamento experimental de bloco ao caso, com três repeti es. Nas variáveis de crescimento da primeira etapa, o genótipo Latispatha de médio porte foi maior ao genótipo Rostrata e as de pequeno porte Golden Torch, Nickeriensis, Sassy e Red Opol n o houve diferen a significativa entre elas. Entre as variáveis de crescimento da segunda etapa, o genótipo que melhor desenvolveu-se foi a Nickeriensis e as que desenvolveram-se menos na variável número de folhas foi o genótipo Latispatha, em altura de plantas a Sassy e em diametro do pseudocaule foram os genótipos Rostrata e Latispatha
Salt tolerance of precocious-dwarf cashew rootstocks: physiological and growth indexes
Carneiro Paulo Torres,Fernandes Pedro Dantas,Gheyi Hans Raj,Soares Frederico Ant?nio Loureiro
Scientia Agricola , 2004,
Abstract: The cashew crop (Anacardium occiedentale L.) is of great economic and social importance for Northeast Brazil, a region usually affected by water and soil salinity. The present study was conducted in a greenhouse to evaluate the effects of four salinity levels established through electrical conductivity of irrigation water (ECw: 0.7, 1.4, 2.1 and 2.8 dS m-1, at 25oC), on growth and physiological indexes of five rootstocks of dwarf-precocious cashew varieties CCP06, CCP09, CCP1001, EMBRAPA50, and EMBRAPA51. Plant height, leaf area, dry weight of root, shoot and total; water content of leaves, root/shoot ratio, leaf area ratio, absolute and relative growth rates and rate of net assimilation were evaluated. The majority of the evaluated variables were found to be affected by ECw and the effects varied among clones; however, no significant interactive effects were observed for factors. The value of ECw = 1.39 dS m-1 was considered as a threshold tolerance for the precocious cashew rootstocks used in this study. The dwarf-precocious cashew is moderately sensible to soil salinity during the formation phase of rootstock. Clones EMBRAPA51 and EMBRAPA50 presented, respectively, the least and the best development indexes.
Gas exchange and nutrient content in leaves of physic nut irrigated with wastewater and doses of phosphorus Trocas gasosas e teor de nutrientes em folhas de pinh o manso irrigado com água residuária e doses de fósforo
Antonio Evami Cavalcante Sousa,Claudivan Feitosa de Lacerda,Hans Raj Gheyi,Frederico Antonio Loureiro Soares
Semina : Ciências Agrárias , 2012,
Abstract: With the objective of evaluating leaf gas exchange and nutrient concentration in plants of Physic nut irrigated with wastewater of domestic origin an experiment was conducted in protected ambient adopting randomized block in factorial layout, to study the effects of five levels of hydric reposition – HR (0.25; 0.50; 0.75; 1.00 and 1.25 times of water consumed by the plant), and two levels of phosphorus (135 and 200 g P2O5 plant-1 year-1) with four repetitions. The data of leaf gas exchange were obtained using a portable photosynthesis meter (IRGA). To determine the nutrient content of the plant, fourth and fifth leaves below the inflorescence was used. The reduction in water supply provoked reduction in the rate of carbon assimilation, limiting the production capacity of the Physic nut plants. The increase in level of hydric reposition with wastewater resulted increase in leaf gas exchange, notably in the rate of carbon assimilation. The accumulation of the nutrient follows the sequence: N > K > Ca > Na > Cl > Mg > P > S > Fe > Mn > Zn > Cu, and with the increase of water supply the leaf contents of phosphorus, zinc and copper increased. The doses of P2O5 did not influence the contents of studied elements. Com o objetivo de avaliar trocas gasosas e teores de minerais em plantas de pinh o manso irrigadas com água residuária de origem doméstica foi conduzido um ensaio em ambiente protegido adotando-se um delineamento em blocos casualizados em um fatorial com cinco níveis de reposi o hídrica (0,25; 0,50; 0,75; 1,00 e 1,25 do consumo de água pela planta) e duas doses de P2O5 (135 e 200 g planta-1) por ano com quatro repeti es. Os dados de trocas gasosas foliares foram obtidos utilizando-se medidor portátil de fotossíntese (IRGA). Para determinar o teor de nutrientes da planta, utilizou-se o limbo foliar localizado entre a quarta e quinta folha abaixo da inflorescência. A redu o da reposi o hídrica provocou diminui o na taxa de assimila o de carbono, limitando a capacidade produtiva das plantas de pinh o manso. O incremento na reposi o hídrica com água residuária proporcionou incremento nas trocas gasosas foliares, notadamente na taxa de assimila o de carbono. Verificou-se que o acúmulo dos elementos segue a sequência: N > K > Ca > Na > Cl > Mg > P > S > Fe > Mn > Zn > Cu, e com o aumento da reposi o hídrica, o fósforo, o zinco e o cobre aumentaram suas concentra es no limbo foliar. As doses de P2O5 aplicadas n o influenciaram os teores de nenhum dos elementos estudados.
Water salinity and initial development of yellow passion fruit
Soares Frederico Ant?nio Loureiro,Gheyi Hans Raj,Viana Sergio Batista Assis,Uyeda Claudio Augusto
Scientia Agricola , 2002,
Abstract: Considering the lack of information on salt tolerance of passion fruit (Passiflora edulis) seedlings, a study was carried out to evaluate the effects of water salinity on the vigor and initial growth in a completely randomized design with 8 levels of electrical conductivity of irrigation water (ECw), varying from 1.0 to 8.0 dS m-1. Salinity delayed the germination process, but relative reduction was observed only above ECw 4.43 dS m-1. Seedling vigor and growth decreased with increasing salinity, however, water at 4 dS m-1 resulted in 85% of vigor and seedlings with more than 50% growth in comparison to the lowest salinity treatment. Based on soil salinity, the passion fruit may be considered as 'moderately tolerant' to salinity during the initial phase.
Emergência, crescimento e produ??o da mamoneira sob estresse salino e aduba??o nitrogenada
Nobre, Reginaldo Gomes;Lima, Geovani Soares de;Gheyi, Hans Raj;Louren?o, Givanildo da Silva;Soares, Lauriane Almeida dos Anjos;
Revista Ciência Agron?mica , 2013, DOI: 10.1590/S1806-66902013000100010
Abstract: the use of saline water in agriculture is becoming a reality in many regions of the world, given the increased demand for fresh water, both for irrigated agriculture, as well as for urban and industrial supply. in this context, the aim of this research was to evaluate the effect of different salinity levels in irrigation water, associated with amounts of nitrogen fertilizer, on the emergence, growth and yield of the castor bean, cv. brs energia, in an experiment where plants were maintained in lysimeters under field conditions, at the ccta / ufcg. a randomised block design in a 5 x 5 factorial with three replications was used to study the effects of five levels of electrical conductivity of the irrigation water (0.4, 1.4, 2.4, 3.4 and 4.4 ds m-1) associated with five levels of nitrogen fertilizer (50, 75, 100, 125 and 150% of the dose recommended for testing in pots). the salinity of the irrigation water from 0.4 ds m-1 affects negatively and in a linear manner the percentage of emergence (pe), the emergence speed index (ive), plant height (ap), the stem diameter (dc), the shoot dry-weight (fspa) and root dry-weight (fsraiz) and the seed mass of the primary raceme (msemrp), whereas increasing levels of nitrogen caused an increase in dc, fspa and fsraiz. the application of increasing doses of n reduced the effect of salinity on the dc and fsraiz of the castor bean cv. brs energia.
Componentes de produ??o de pinh?o manso irrigado com água de diferentes condutividades elétrica e doses de fósforo
Sousa, Antonio Evami Cavalcante;Gheyi, Hans Raj;Soares, Frederico Antonio Loureiro;Nobre, Reginaldo Gomes;Nascimento, Elka Costa Santos;
Ciência Rural , 2012, DOI: 10.1590/S0103-84782012000600009
Abstract: the physic nut has attracted considerable interest in recent years because of the high potential to provide oil for biofuel production and this has caused the rapid expansion of cultivated area worldwide. this research aimed to evaluate the influence of irrigation with water of different electrical conductivity (ecw) and two doses of phosphorus on the production components of physic nut during the third year of production. a randomized block design in a factorial (5x2) was adopted with four repetitions, with five levels of salinity (ecw - 0.6 control; 1.2; 1.8; 2.4 and 3.0ds m-1) of the irrigation water and two doses of p2o5 (135 and 200g plant-1 year-1), in which the water of 0.6ds m-1 refers to municipal supply water and the dose of 135g plant-1 is the recommended dose for physic nut. plants were cultivated in recipient of 200l and irrigated at intervals of three days. the number of days for inflorescence, number of clusters plant-1, grain yield and oil content of physic nut seeds were negatively affected by the increasing salinity of the irrigated water. the cultivation of physic nut irrigated with electrical conductivity of 1.3ds m-1 reduces the productivity by 10% and consequently the seed oil content. only the number of days for inflorescence was affected by phosphorus doses. a positive and significant correlation between weight of 100 seeds and oil content of seeds was observed and in the treatment with the lowest ecw the values obtained were respectively 90.26g and 36.39%.
Teor de óleo no pinh?o manso em fun??o de laminas de água residuária
Sousa, Antonio Evami Cavalcante;Gheyi, Hans Raj;Soares, Frederico Antonio Loureiro;Medeiros, Everaldo Paulo de;Nascimento, Elka Costa Santos;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011000100015
Abstract: the objective of this work was to study the influence of different levels of wastewater and two doses of phosphorus on the productivity and oil content of physic nut seeds. a randomized design in a 5x2 factorial arrangement was used, with four replicates with one plant per plot. treatments consisted of a combination of five levels of irrigation depths (0.25, 0.50, 0.75, 1.00 and 1.25 of water consumption) and two doses of p2o5 (135 and 200 g per plant) per year. the productivity and oil content of the seeds were positively and significantly affected by water depths, while phosphorus doses had no influence.
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