The objective of this study was to evaluate the productive and economic performance of a forage cactus and sorghum intercropping system in relation to a forage cactus single cropping system under different irrigation blades with saline water. The study was conducted in Serra Talhada, State of Pernambuco, in a randomized block design, consisting of a factorial arrangement with split-plot parcels (5×2) and four replications. The five plots were the irrigation depths based on the reference evapotranspiration (ETo) (0, 8.75, 17.5, 26.25, and 35% ETo) and the two cropping systems were single forage cactus cropping and cactus intercropped with sorghum. The experiment was conducted for one year, with one forage cactus cycle and two cycles of sorghum. Yields were obtained at the end of the cycles. Economic profitability was analyzed by means of net revenue (NR) and the benefit/cost ratio (B/C), with cactus forage sold as forage or as "seed" and sorghum as forage. Net revenue and B/C simulations were carried out over an eight-year useful life span of the irrigation system. Increasing irrigation depth increased the dry matter yield of the intercropping system because of higher sorghum yield. Based on the NR and B/C ratio values, forage cactus and sorghum produced as forage produced higher economic outcomes in the intercropping system and showed a higher profitability from the 2nd year of implementation of the irrigation system. Forage cactus and sorghum intercropping irrigated with saline water is therefore recommended for forage production in the Brazilian semi-arid region.

The objective of this study was to evaluate the productive and economic performance of a forage cactus and sorghum intercropping system in relation to a forage cactus single cropping system under different irrigation blades with saline water. The study was conducted in Serra Talhada, State of Pernambuco, in a randomized block design, consisting of a factorial arrangement with split-plot parcels (5×2) and four replications. The five plots were the irrigation depths based on the reference evapotranspiration (ETo) (0, 8.75, 17.5, 26.25, and 35% ETo) and the two cropping systems were single forage cactus cropping and cactus intercropped with sorghum. The experiment was conducted for one year, with one forage cactus cycle and two cycles of sorghum. Yields were obtained at the end of the cycles. Economic profitability was analyzed by means of net revenue (NR) and the benefit/cost ratio (B/C), with cactus forage sold as forage or as "seed" and sorghum as forage. Net revenue and B/C simulations were carried out over an eight-year useful life span of the irrigation system. Increasing irrigation depth increased the dry matter yield of the intercropping system because of higher sorghum yield. Based on the NR and B/C ratio values, forage cactus and sorghum produced as forage produced higher economic outcomes in the intercropping system and showed a higher profitability from the 2nd year of implementation of the irrigation system. Forage cactus and sorghum intercropping irrigated with saline water is therefore recommended for forage production in the Brazilian semi-arid region. | Objetivou-se avaliar o desempenho produtivo-econômico da consorciação palma forrageira e sorgo em relação ao sistema de plantio exclusivo da palma forrageira sob diferentes lâminas de irrigação com água salina. A pesquisa foi conduzida em Serra Talhada, PE, com delineamento em blocos ao acaso, arranjo fatorial com parcelas subdivididas (5×2), quatro repetições, sendo considerada como parcelas as lâminas de irrigação complementar com base na evapotranspiração de referência (0; 8,75; 17,5; 26,25 e 35% ETo), e as subparcelas, os sistemas de plantio: palma exclusiva e consórcio palma-sorgo. O experimento foi conduzido por um ano, sendo um ciclo de palma e dois ciclos do sorgo. Ao final foram obtidas as produtividades de matéria fresca e seca. A rentabilidade econômica foi analisada por meio da receita líquida (RL) e da relação benefício/custo (B/C) da palma destinada à venda tanto para forragem como “semente” para o plantio, e do sorgo para produção de forragem. Simulações de RL e B/C foram feitas ao longo da vida útil de oito anos do sistema de irrigação. As lâminas de água aumentaram a produtividade de matéria seca do consórcio, devido ao benefício gerado ao sorgo. Com base na RL e B/C, verificou-se que a palma e o sorgo destinados à venda como forragem mostraram mais vantagem quando consorciadas e maior rentabilidade a partir do 2º ano de implantação do sistema de irrigação. Conclui-se que, o consórcio palma forrageira e sorgo irrigado com água salina deve ser recomendado para a produção de forragem no Semiárido brasileiro.

Researches evaluating the use of mulch has contributing to optimize soil management towards sustainability, and improving soil quality. The objective of this study was to evaluate the efficiency of mulching on the reduction of erosion in a soil with sorghum (Sorghum bicolor L. Moench) crops subjected to simulated rainfall and increased soil organic carbon. The experiment was carried out from August to December 2013 under field conditions, using a randomized block design with three replications. The treatments consisted of sorghum with mulch, using the local vegetation available in the area; and sorghum without mulch. Simulated rainfalls were performed in three different periods of the crop cycle (initial, intermediate, and final), using a rainfall simulator. The use of mulch in soils with sorghum crops was efficient in improving soil water retention in all phases of the crop, and maintaining soil moisture during the rainfall intervals used, resulting in the absence of plant water loss, and greater contribution to soil organic carbon.

Researches evaluating the use of mulch has contributing to optimize soil management towards sustainability, and improving soil quality. The objective of this study was to evaluate the efficiency of mulching on the reduction of erosion in a soil with sorghum (Sorghum bicolor L. Moench) crops subjected to simulated rainfall and increased soil organic carbon. The experiment was carried out from August to December 2013 under field conditions, using a randomized block design with three replications. The treatments consisted of sorghum with mulch, using the local vegetation available in the area; and sorghum without mulch. Simulated rainfalls were performed in three different periods of the crop cycle (initial, intermediate, and final), using a rainfall simulator. The use of mulch in soils with sorghum crops was efficient in improving soil water retention in all phases of the crop, and maintaining soil moisture during the rainfall intervals used, resulting in the absence of plant water loss, and greater contribution to soil organic carbon. | Pesquisas que avaliem o uso de cobertura morta no solo tem grande aceitação, uma vez que otimiza o manejo sustentável e melhora a qualidade do solo. Objetivou-se, com o presente trabalho, avaliar a eficiência da cobertura morta na redução das taxas erosivas do solo em cultivo de sorgo (Sorghum bicolor L. Moench) submetido à chuva simulada, bem como o incremento de carbono orgânico no solo. O experimento foi desenvolvido no período de agosto a dezembro de 2013 sob condição de campo, onde foram estabelecidos os seguintes tratamentos: sorgo com cobertura morta (CM) utilizando-se a vegetação espontânea da área e sorgo sem cobertura morta (SM), com três repetições em blocos casualizados. Foi realizada chuva simulada em três períodos distintos (nicial, intermediário e final do ciclo da cultura), utilizando-se um simulador de chuvas. Em todas as fases da cultura, o uso da cobertura morta no solo em cultivo de sorgo se mostrou eficiente por proporcionar maior retenção da umidade no solo, a qual se manteve por mais tempo entre os intervalos de chuva, resultando na ausência de perda de água, além de proporcionar maior aporte de carbono orgânico no solo.

The use of stimulants in the establishment of arbuscular mycorrhizal fungi has great potential in contributing to P uptake by plants. This study aimed to evaluate the effect of isoflavonoid formononetin as mycorrhization stimulant on soybean associated with phosphate fertilizer in Oxisols with intermediate (OPi) and low (OPl) phosphorus availability, in the Cerrado region of Piauí. The experiment in each soil consisted of randomized blocks design in a 4×4 factorial scheme, with four replications. The treatments comprised of four phosphorus doses (0, 26.66, 40 and 80 kg ha-1 P2O5), and four isoflavonoid formononetin doses (0, 0.5, 0.9 and 1.8 g kg-1 soybean seeds). The variables evaluated were soybean growth, yield, nodulation and mycorrhizal colonization rate. With the exception of mycorrhizal colonization rate in OPi, plant height and number of pods per plant in OPl, the other variables were not affected by the application of isoflavonoid formononetin, in both soils. Yield linearly increased with increase in the phosphorus doses in OPl, and presented agronomic efficiency of ~15 kg ha-1 grain for each kg ha-1 P2O5 applied to the soil.

The use of stimulants in the establishment of arbuscular mycorrhizal fungi has great potential in contributing to P uptake by plants. This study aimed to evaluate the effect of isoflavonoid formononetin as mycorrhization stimulant on soybean associated with phosphate fertilizer in Oxisols with intermediate (OPi) and low (OPl) phosphorus availability, in the Cerrado region of Piauí. The experiment in each soil consisted of randomized blocks design in a 4×4 factorial scheme, with four replications. The treatments comprised of four phosphorus doses (0, 26.66, 40 and 80 kg ha-1 P2O5), and four isoflavonoid formononetin doses (0, 0.5, 0.9 and 1.8 g kg-1 soybean seeds). The variables evaluated were soybean growth, yield, nodulation and mycorrhizal colonization rate. With the exception of mycorrhizal colonization rate in OPi, plant height and number of pods per plant in OPl, the other variables were not affected by the application of isoflavonoid formononetin, in both soils. Yield linearly increased with increase in the phosphorus doses in OPl, and presented agronomic efficiency of ~15 kg ha-1 grain for each kg ha-1 P2O5 applied to the soil. | O uso de estimulantes para o estabelecimento de fungos micorrízicos arbusculares tem grande potencial em contribuir para a absorção de P pelas plantas. Objetivou-se avaliar a eficácia do isoflavonóide formononetina como estimulante da micorrização na cultura da soja, associada a adubação fosfatada, em dois Latossolos com teores de fósforo disponível médio (LPm) e baixo (LPb) no Cerrado piauiense. O delineamento experimental em cada solo foi em blocos casualizados no esquema fatorial 4×4, com quatro repetições. Os tratamentos foram constituídos por quatro doses de fósforo (0; 26,66; 40 e 80 kg ha-1 de P2O5) e quatro doses do isoflavonóide formononetina (0; 0,5; 0,9 e 1,8 g kg-1 de semente de soja). As variáveis avaliadas foram, o crescimento, a produção, a nodulação e taxa de colonização micorrízica da soja. Com exceção da taxa de colonização micorrízica no LPm, altura e número de vagens por planta de soja no LPb, as demais variáveis, não foram influenciados pela aplicação do isoflavonóide formononetina, em ambos os solos. A produtividade cresceu linearmente ao incremento das doses de fósforo no LPb, apresentando uma eficiência agronômica de ~15 kg ha-1 de grãos para cada kg ha-1 de P2O5 aplicado no solo.

The interaction Fusarium oxysporum f. sp. cubense (Foc) x nematode and the genetic variability of Foc are the main problems with potential to affect the use of resistant varieties in the management of the Panama disease. The objective of this work was to evaluate the interaction between Foc and Meloidogyne javanica on the banana of the Prata Anã, Grande Naine and BRS Princesa cultivars. The experiment was conducted in a randomized block design, with six treatments and ten replications, which differed in the inoculation time of each pathogen. Simultaneous inoculation with Foc and M. javanica, inoculation with Foc one week before inoculation with M. javanica, and inoculation with M. javanica one week before inoculation with Foc. In addition to the controls, Foc isolated, M. javanica isolated, and cultivars without the pathogens. The seedlings were transplanted in 3-liter pots with sterile soil infested with 40 grams of Foc inoculum at the concentration of 1x106CFU/gram and 1000 eggs and J2 of M. javanica. At the end of 56 days, the treatments with 'Grande Naine' presented the highest reproduction factors of M. javanica. In the 'Prata Anã' no interaction was observed between Foc x M. javanica. The treatments with simultaneous inoculation of the two pathogens, and with Foc a week before, in the 'BRS Princesa', presented the highest external disease indices (DI), which promoted the highest AUDPC. The highest internal DI were observed in the treatments Foc+Mj+Grande Naine, Foc+Mj+BRS Princesa, Mj+Grande Naine+Foc and Foc+BRS Princesa+Mj. The simultaneous presence of M. javanica and Foc increases the severity of the Panama disease in Grande Naine and BRS Princesa cultivars.

The interaction Fusarium oxysporum f. sp. cubense (Foc) x nematode and the genetic variability of Foc are the main problems with potential to affect the use of resistant varieties in the management of the Panama disease. The objective of this work was to evaluate the interaction between Foc and Meloidogyne javanica on the banana of the Prata Anã, Grande Naine and BRS Princesa cultivars. The experiment was conducted in a randomized block design, with six treatments and ten replications, which differed in the inoculation time of each pathogen. Simultaneous inoculation with Foc and M. javanica, inoculation with Foc one week before inoculation with M. javanica, and inoculation with M. javanica one week before inoculation with Foc. In addition to the controls, Foc isolated, M. javanica isolated, and cultivars without the pathogens. The seedlings were transplanted in 3-liter pots with sterile soil infested with 40 grams of Foc inoculum at the concentration of 1x106CFU/gram and 1000 eggs and J2 of M. javanica. At the end of 56 days, the treatments with 'Grande Naine' presented the highest reproduction factors of M. javanica. In the 'Prata Anã' no interaction was observed between Foc x M. javanica. The treatments with simultaneous inoculation of the two pathogens, and with Foc a week before, in the 'BRS Princesa', presented the highest external disease indices (DI), which promoted the highest AUDPC. The highest internal DI were observed in the treatments Foc+Mj+Grande Naine, Foc+Mj+BRS Princesa, Mj+Grande Naine+Foc and Foc+BRS Princesa+Mj. The simultaneous presence of M. javanica and Foc increases the severity of the Panama disease in Grande Naine and BRS Princesa cultivars. | A interação Fusarium oxysporum f. sp. cubense (Foc) x nematoide e a variabilidade genética de Foc são os principais problemas com potencial de afetar o uso de variedades resistentes no manejo do mal-do-Panamá. O objetivo do trabalho foi avaliar a interação entre Foc e Meloidogyne javanica sobre as cultivares de bananeiras, Prata Anã, Grande Naine e BRS Princesa. O experimento foi conduzido em DBC, com seis tratamentos e dez repetições, os quais se diferenciaram no tempo de inoculação de cada patógeno. Inoculação simultânea de Foc e M. javanica, inoculação de Foc uma semana antes de M. javanica e inoculação de M. javanica uma semana antes de Foc. Além dos controles, Foc isolado, M. javanica isolado e cultivares sem patógenos. As mudas foram transplantadas em vasos de três litros com solo estéril infestado com 40 gramas de inóculo de Foc na concentração de 1x106UFC/grama e 1000 ovos e J2 de M. javanica. Ao final de 56 dias, os tratamentos em ‘Grande Naine’ apresentaram os maiores fatores de reprodução de M. javanica. Em ‘Prata Anã’ não foi observado interação entre Foc x M. javanica. Os tratamentos com inoculação simultânea dos dois patógenos e com Foc uma semana antes, em ‘BRS Princesa’, apresentaram os maiores índices de doença (ID) externos, o que proporcionou as maiores AACPD. Os maiores ID internos foram observados nos tratamentos, Foc+Mj+Grande Naine, Foc+Mj+BRS Princesa, Mj+Grande Naine+Foc e Foc+BRS Princesa+Mj. A presença conjunta de M. javanica e Foc aumenta a severidade do mal-do-Panamá nas cultivares Grande Naine e BRS Princesa.

The objective of the present work was to evaluate the use of extracts of leaves and fruits of neem (Azadirachta indica Juss) as coating for papaya Formosa fruits aiming to maintain their quality during post-harvest storage. A completely randomized experimental design in a 5x5 factorial arrangement was used, with 3 replications of 2 papaya fruits per plot. The treatments consisted of five coatings with extracts of neem leaves and fruits (leaf extracts at 5 and 10%, fruit extracts at 5 and 10% and a control treatment without coating) and five storage periods (0, 3, 6, 9 and 12 days) under mean temperature of 30.4 °C and relative humidity of 42%. The fruit weight loss, external appearance, pulp firmness, titratable acidity and soluble solids were evaluated, and the fungi species on the fruit surface of each storage were identified and quantified. The treatments with extract of neem leaves and fruits at 5% had papaya fruits with best external quality and provided best control of growth of phytopathogenic fungi. Regarding external appearance, papaya fruits coated with extracts of neem leaves and fruits at 5% had a shelf life of 12 days, while those coated with extracts at 10% had a shelf life of 9 days.

The objective of the present work was to evaluate the use of extracts of leaves and fruits of neem (Azadirachta indica Juss) as coating for papaya Formosa fruits aiming to maintain their quality during post-harvest storage. A completely randomized experimental design in a 5x5 factorial arrangement was used, with 3 replications of 2 papaya fruits per plot. The treatments consisted of five coatings with extracts of neem leaves and fruits (leaf extracts at 5 and 10%, fruit extracts at 5 and 10% and a control treatment without coating) and five storage periods (0, 3, 6, 9 and 12 days) under mean temperature of 30.4 °C and relative humidity of 42%. The fruit weight loss, external appearance, pulp firmness, titratable acidity and soluble solids were evaluated, and the fungi species on the fruit surface of each storage were identified and quantified. The treatments with extract of neem leaves and fruits at 5% had papaya fruits with best external quality and provided best control of growth of phytopathogenic fungi. Regarding external appearance, papaya fruits coated with extracts of neem leaves and fruits at 5% had a shelf life of 12 days, while those coated with extracts at 10% had a shelf life of 9 days. | O presente trabalho teve como objetivo avaliar uso de extrato à base de folhas e de frutos do nim (Azadirachta indica Juss) como recobrimento na manutenção da qualidade pós-colheita do mamão Formosa. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial 5 x 5, no qual o primeiro fator constou dos tipos de recobrimentos a base de folhas e frutos do nim (controle TC, extrato das folhas a 5% - T1, extrato das folhas a 10% - T2, extrato dos frutos a 5% - T3 e extrato dos frutos a 10% - T4) e o segundo fator dos tempos de armazenamento (0, 3, 6, 9 e 12 dias) a temperatura média de 30,4 ºC e UR de 42%, com 3 repetições de 2 frutos por parcela. A cada tempo de armazenamento foram avaliadas perda de massa, aparência externa, firmeza da polpa, teor de acidez titulável, sólidos solúveis, percentual de fungos na superfície dos frutos e identificação de espécies de fungos. O extrato das folhas e dos frutos de nim a 5% apresentaram os melhores resultados por manter a qualidade externa dos frutos, além de controlar o crescimento dos fungos fitopatogênicos. Com base na aparência externa, os frutos de mamão tratados com extratos das folhas e dos frutos do nim a 5% tiveram vida útil de 12 dias. Os frutos recobertos com extratos das folhas e dos frutos a 10% apresentaram vida útil de 9 dias.

Leguminous species can improve nutrient cycling and chemical quality of Oxisols, resulting in higher productivity of intercropped crops. Thus, this research aimed to evaluate the decomposition rate and nutrient accumulation in legume stubble, as well as its contribution to soil chemical attributes, the growth of baru trees (Dipteryx alata Vogel), and yield of intercropped maize in an agroforestry system. The experiment was developed during the crop years of 2010-2011 and 2011-2012, in Goiás State, Brazil. The experimental design was a randomized block with five replicates. Leguminous species consisted of sunn hemp (Crotalaria juncea), jack bean (Canavalia ensiformis), pigeon pea (Cajanus cajan), Stylosanthes (Stylosanthes macrocephala - 20% and Stylosanthes capitata - 80%), and spontaneous vegetation (control treatment). The decomposition rates of legume and spontaneous vegetation residues remained unchanged in the agroforestry system. Sunn hemp, jack bean, and Stylosanthes plants are advantageous options for total accumulation of nutrients. However, sunn hemp grown as straw cover for next crop seasons increases the available phosphorus levels in the soil and productivity of maize cobs. With this coverage, maize productivity values were up to 24% higher than were those with maize growing on spontaneous vegetation, besides having no effect on the growth of baru trees.

Leguminous species can improve nutrient cycling and chemical quality of Oxisols, resulting in higher productivity of intercropped crops. Thus, this research aimed to evaluate the decomposition rate and nutrient accumulation in legume stubble, as well as its contribution to soil chemical attributes, the growth of baru trees (Dipteryx alata Vogel), and yield of intercropped maize in an agroforestry system. The experiment was developed during the crop years of 2010-2011 and 2011-2012, in Goiás State, Brazil. The experimental design was a randomized block with five replicates. Leguminous species consisted of sunn hemp (Crotalaria juncea), jack bean (Canavalia ensiformis), pigeon pea (Cajanus cajan), Stylosanthes (Stylosanthes macrocephala - 20% and Stylosanthes capitata - 80%), and spontaneous vegetation (control treatment). The decomposition rates of legume and spontaneous vegetation residues remained unchanged in the agroforestry system. Sunn hemp, jack bean, and Stylosanthes plants are advantageous options for total accumulation of nutrients. However, sunn hemp grown as straw cover for next crop seasons increases the available phosphorus levels in the soil and productivity of maize cobs. With this coverage, maize productivity values were up to 24% higher than were those with maize growing on spontaneous vegetation, besides having no effect on the growth of baru trees. | O uso de espécies leguminosas poderá favorecer a ciclagem de nutrientes e a qualidade química dos latossolos, o que de certa forma promoverá maior desempenho dos cultivos consorciados. Desta forma, objetivou-se com esta pesquisa avaliar a taxa de decomposição e o acúmulo de nutrientes em leguminosas, além dos atributos químicos do solo, crescimento de barueiros e produtividade de milho cultivados em rotação no sistema agroflorestal. A pesquisa foi realizada em consórcio com árvores de barueiros (Dipteryx alata Vogel), durante o período das safras 2010-2011 e 2011-2012, no estado de Goiás, Brasil, O delineamento experimental foi em blocos casualizados, com cinco repetições. As leguminosas utilizadas foram: crotalária (Crotalaria juncea); feijão de porco (Canavalia ensiformis); feijão guandu (Cajanus cajan); estilosantes campo grande (Stylosanthes macrocephala - 20% e Stylosanthes capitata - 80%) e vegetação espontânea (tratamento controle). A taxa de decomposição dos resíduos de leguminosas e vegetação espontânea não é afetada no sistema agroflorestal. A crotalária, o feijão de porco e o estilosantes apresentam-se como opções vantajosas para o acúmulo total de nutrientes. Porém, o cultivo de crotalária com manejo de palhada visando rotação para próxima safra aumenta os teores de fósforo disponível no solo e a produtividade de espigas de milho verde com valores até 24% superiores em relação à área mantida sob vegetação espontânea, além de não afetar o crescimento das árvores.

The objective with this work was to evaluate the effect of the agricultural gypsum, associated with phosphate fertilization, on the nutrition, development and yield of soybean and corn in succession, under no-tillage system. The experiment was conducted at Universidade Federal de Goiás, Regional Jataí, in a randomized blocks design 5x3 factorial arrangement, with 4 replicates. The first factor consisted of the gypsum doses (0, 1, 2, 4 and 8 Mg ha-1) and the second the phosphorus doses (0, 50 and 100% of the recommended dose). Leaf nutrient contents, leaf area index, SPAD index, dry plant mass, final plant population, one thousand grain mass and grain yield were evaluated in the crops. In the soybean, the number of pods was also obtained and in the corn the average ear length, number of rows per ear, number of grain per ear and number of ears. Phosphorus doses increase leaf Mg contents in soybean and corn. The application of gypsum reduces the Mg and K leaf contents and increases the Ca, S, and Mn contents in the two cultures. Gypsum provides increases in the SPAD index in soybean plants. The unbalance of the N / K ratio in corn leaves, provided by the increase of the gypsum doses, reduces the leaf area of this crop. Doses of P and gypsum do not influence the yield of soybeans and maize.

The objective with this work was to evaluate the effect of the agricultural gypsum, associated with phosphate fertilization, on the nutrition, development and yield of soybean and corn in succession, under no-tillage system. The experiment was conducted at Universidade Federal de Goiás, Regional Jataí, in a randomized blocks design 5x3 factorial arrangement, with 4 replicates. The first factor consisted of the gypsum doses (0, 1, 2, 4 and 8 Mg ha-1) and the second the phosphorus doses (0, 50 and 100% of the recommended dose). Leaf nutrient contents, leaf area index, SPAD index, dry plant mass, final plant population, one thousand grain mass and grain yield were evaluated in the crops. In the soybean, the number of pods was also obtained and in the corn the average ear length, number of rows per ear, number of grain per ear and number of ears. Phosphorus doses increase leaf Mg contents in soybean and corn. The application of gypsum reduces the Mg and K leaf contents and increases the Ca, S, and Mn contents in the two cultures. Gypsum provides increases in the SPAD index in soybean plants. The unbalance of the N / K ratio in corn leaves, provided by the increase of the gypsum doses, reduces the leaf area of this crop. Doses of P and gypsum do not influence the yield of soybeans and maize. | Objetivou-se com este trabalho avaliar o efeito do gesso agrícola associado à adubação fosfatada, sobre a nutrição, desenvolvimento e produtividadeda da soja e do milho em sucessão, sob sistema plantio direto. O experimento foi conduzido na Universidade Federal de Goiás, Regional Jataí, com delineamento experimental constituído de 15 tratamentos estabelecidos em blocos casualizados em esquema fatorial 5x3, com 4 repetições. O primeiro fator correspondeu as doses de gesso (0, 1, 2, 4 e 8 Mg ha-1) e o segundo fator às doses de fósforo (0, 50 e 100% da dose recomendada). Foram avaliados nas culturas os teores foliares de nutrientes, índice de área foliar, índice SPAD, massa de plantas secas, população final de plantas, massa de mil grãos e produtividade de grãos. Ainda, na soja foi obtido o número de vagens e no milho o comprimento médio de espiga, número de fileiras de grãos por espiga, número de grãos por espiga e o número de espigas. As doses de fósforo aumentam os teores foliares de Mg na soja e no milho. A aplicação de gesso reduz os teores de Mg e K e aumentam os de Ca, S e Mn nas duas culturas. O gesso proporciona incrementos no índice SPAD em plantas de soja. O desbalanço da relação N/K nas folhas de milho, proporcionadas pelo incremento das doses de gesso, reduz a área foliar desta cultura. Doses de P e de Gesso não influenciam a produtividade da soja e do milho safrinha.

In wheat crops, it is often observed that the number of plants per area is lower than that of viable seeds used, which may be related to both environmental conditions and seed vigor. The aim of this study was to assess the effect of seed vigor level at different sowing densities on growth, development, and grain yield in wheat cultivars. The experiments were conducted in Londrina and Ponta Grossa, PR, Brazil, under a randomized block design in a 2 × 2 × 3 factorial scheme, with four replications. Two seed vigor levels (high and low), two sowing densities (200 and 400 viable seeds per m2), and three wheat cultivars (BRS Sabiá, BRS Gaivota, and BRS Gralha Azul) were assessed. In order to assess growth and development, plant samples were collected at the phenological stages of seedling growth, stem elongation, booting, and ear emergence. We assessed the emergence of seedlings, height and dry matter of plant shoot, and grain yield. The sowing density of 200 seeds per m2 led to a higher shoot dry matter production per plant at the stages booting and ear emergence. The cultivar BRS Sabiá presented the highest grain yield in Londrina, while BRS Sabiá and BRS Gralha Azul presented the highest grain yield in Ponta Grossa. High vigor seeds favor stand establishment, growth and development of plants at early phenological stages, and grain yield of wheat.

In wheat crops, it is often observed that the number of plants per area is lower than that of viable seeds used, which may be related to both environmental conditions and seed vigor. The aim of this study was to assess the effect of seed vigor level at different sowing densities on growth, development, and grain yield in wheat cultivars. The experiments were conducted in Londrina and Ponta Grossa, PR, Brazil, under a randomized block design in a 2 × 2 × 3 factorial scheme, with four replications. Two seed vigor levels (high and low), two sowing densities (200 and 400 viable seeds per m2), and three wheat cultivars (BRS Sabiá, BRS Gaivota, and BRS Gralha Azul) were assessed. In order to assess growth and development, plant samples were collected at the phenological stages of seedling growth, stem elongation, booting, and ear emergence. We assessed the emergence of seedlings, height and dry matter of plant shoot, and grain yield. The sowing density of 200 seeds per m2 led to a higher shoot dry matter production per plant at the stages booting and ear emergence. The cultivar BRS Sabiá presented the highest grain yield in Londrina, while BRS Sabiá and BRS Gralha Azul presented the highest grain yield in Ponta Grossa. High vigor seeds favor stand establishment, growth and development of plants at early phenological stages, and grain yield of wheat. | Na cultura do trigo, frequentemente, observa-se que o estabelecimento do número de plantas por área é inferior ao de sementes viáveis utilizadas, o que pode estar relacionado tanto a condições do ambiente quanto ao vigor de sementes. O objetivo foi avaliar o efeito do nível de vigor de sementes, em diferentes densidades de semeadura, sobre o crescimento, o desenvolvimento e o rendimento de grãos em cultivares de trigo. Os experimentos foram conduzidos em Londrina e Ponta Grossa, PR, Brasil, sob o delineamento experimental de blocos casualizados, em esquema fatorial 2 x 2 x 3, com quatro repetições. Foram avaliados dois níveis de vigor de sementes (alto e baixo), duas densidades de semeadura (200 e 400 sementes viáveis por m2) e três cultivares de trigo (BRS Sabiá, BRS Gaivota e BRS Gralha Azul). Para avaliação do crescimento e desenvolvimento foram realizadas coletas de plantas nos estádios fenológicos de desenvolvimento da plântula, alongamento do colmo, emborrachamento e emergência da inflorescência. As avaliações efetuadas foram: emergência de plântulas, altura e massa seca da parte aérea de plantas e produtividade de grãos. A densidade de semeadura de 200 sementes por m2 acarreta maior produção de massa seca da parte aérea por planta nos estádios de emborrachamento e emergência da inflorescência. Em Londrina, a cultivar BRS Sabiá e, em Ponta Grossa, a BRS Sabiá e a BRS Gralha Azul apresentam maiores produtividades de grãos. Sementes de alto vigor favorecem o estabelecimento do estande, o crescimento e o desenvolvimento das plantas nos estádios fenológicos iniciais e a produtividade de grãos de trigo.

Título em português: Crescimento e rendimento de trigo em resposta ao vigor de sementes e densidades de semeadura.

Irrigation with brackish water is common in the semiarid region of the Brazilian Northeast, potentiating the process of salinization of the soil in these areas. The hydroponic system stands out as an important strategy for crop management in semiarid regions, since crops show greater tolerance to the salt stress under hydroponic conditions, which minimize the effects of soil salinization. Thus, the objective of this work was to evaluate the effects of salt stress on the growth, fruit yield and mineral nutrition of sweet pepper in hydroponic system, using brackish water and coconut fiber substrate. The experiment was conducted in Recife, State of Pernambuco, Brazil (8°3'15''S, 34°52'53''W). A randomized block experimental design in a 5x2 factorial arrangement with five replications was used, consisting of five water salinity levels of the nutrient solution (2.0; 3.5; 4.5; 5.5 and 6.5 dS m-1) and two sweet pepper cultivars (Bruno and Rubia). The increasing salinity level of the nutrient solution decreased the fruit yield of the cultivars evaluated, reduced the potassium, phosphorus and sulfur, and increased the sodium and chlorine contents in the leaf tissues. The Ca contents of the cultivar Bruno decreased with increasing salinity, and increased in the cultivar Rubia. The cultivar Rubia stood out with the highest fruit yield and ionic selectivity, accumulating high amounts of potassium and calcium and maintaining low Na and Cl contents. The fruit yield of the cultivar Rubia (39.9 t ha-1) grown under solution with electrical conductivity of up to 3.5 dS m-1, denotes the potential viability of growing this cultivar under hydroponic conditions.

Irrigation with brackish water is common in the semiarid region of the Brazilian Northeast, potentiating the process of salinization of the soil in these areas. The hydroponic system stands out as an important strategy for crop management in semiarid regions, since crops show greater tolerance to the salt stress under hydroponic conditions, which minimize the effects of soil salinization. Thus, the objective of this work was to evaluate the effects of salt stress on the growth, fruit yield and mineral nutrition of sweet pepper in hydroponic system, using brackish water and coconut fiber substrate. The experiment was conducted in Recife, State of Pernambuco, Brazil (8°3'15''S, 34°52'53''W). A randomized block experimental design in a 5x2 factorial arrangement with five replications was used, consisting of five water salinity levels of the nutrient solution (2.0; 3.5; 4.5; 5.5 and 6.5 dS m-1) and two sweet pepper cultivars (Bruno and Rubia). The increasing salinity level of the nutrient solution decreased the fruit yield of the cultivars evaluated, reduced the potassium, phosphorus and sulfur, and increased the sodium and chlorine contents in the leaf tissues. The Ca contents of the cultivar Bruno decreased with increasing salinity, and increased in the cultivar Rubia. The cultivar Rubia stood out with the highest fruit yield and ionic selectivity, accumulating high amounts of potassium and calcium and maintaining low Na and Cl contents. The fruit yield of the cultivar Rubia (39.9 t ha-1) grown under solution with electrical conductivity of up to 3.5 dS m-1, denotes the potential viability of growing this cultivar under hydroponic conditions. | A irrigação com águas salobra, frequente na região semiárida do nordeste brasileiro, potencializa o processo de salinização do solo nessas áreas. O cultivo hidropônico destaca-se como uma importante estratégia de convivência com o semiárido, uma vez que as culturas apresentam maior tolerância ao estresse salino nestas condições de cultivo, as quais minimizam os efeitos da salinização dos solos. O objetivo deste trabalho foi avaliar os efeitos da salinidade sobre o crescimento, produção e nutrição mineral de pimentão em cultivo hidropônico utilizando água salina em substrato de fibra de coco. O experimento foi conduzido em Recife, Pernambuco, Brasil (8°3'15'' S, 34°52'53'' W). Foi utilizado o delineamento experimental em blocos casualizados com fatorial 5x2, com cinco repetições, consistindo em cinco níveis de salinidade da solução nutritiva (2,0; 3,5; 4,5; 5,5 e 6,5 dS m-1) e duas cultivares de pimentão (Bruno e Rúbia). O incremento dos níveis de salinidade da solução nutritiva diminuiu a produção de frutos das cultivares avaliadas, reduziu os teores de potássio, fósforo e enxofre e aumentou os teores de sódio e cloro no tecido foliar. O teor de Ca da cv. Bruno decresceu em função do aumento da salinidade, e a apresentou aumento na cv. Rúbia. A cv. Rúbia destacou-se pela maior produtividade e maior eficiência na seletividade iônica, sendo capaz de acumular mais potássio e cálcio, e manter menores teores de Na e Cl. A produtividade da cv. Rúbia (39,9 t ha-1) quando cultivada em solução com condutividade elétrica de até 3,5 dS m-1, indica a viabilidade potencial de seu cultivo em condições hidropônicas.