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Nitrogen fertilization can provide greater nutritional support and mitigate salt stress in the millet crop. The aim of this study was to evaluate the physiological responses and agronomic performance of millet crop subjected to nitrogen fertilization and irrigation water salinity. The study was carried out in a greenhouse, using a completely randomized design in a 5 × 2 factorial scheme, with four replications, with five doses of nitrogen (40; 60; 80; 100 and 120 kg ha−1 of N), and two levels of electrical conductivity for the irrigation water: 0.3 and 4.0 dS m−1. We concluded that salt stress increased leaf sodium levels and had a negative impact on stalk and panicle dry mass, leaf gas exchange, mineral element concentrations (K, P, and Ca), and water use efficiency. The use of lower-salinity water associated with increased nitrogen fertilization provides greater stalk and panicle dry mass, photosynthesis, water use efficiency, chlorophyll index, leaf potassium concentration, and biomass production. The adverse effects of salt stress were evident in decreased transpiration and stomatal conductance, alongside reductions in leaf phosphorus and calcium levels, coupled with elevated leaf sodium concentrations, particularly as nitrogen fertilization rates increased in potted millet plants. These findings offer insights for devising strategies aimed at mitigating the detrimental effects of salt stress on millet plant nutrition through targeted nitrogen fertilization approaches.

The study hypothesis proposes that the use of Trichoderma, associated with fertilization with 100% of the recommended phosphorus, may mitigate saline stress and maximize the productivity and quality of the tuberous root. This study aims to evaluate the mitigating effects of phosphate fertilization and Trichoderma harzianum in beet plants under salt stress, by measuring the initial growth, leaf gas exchange, productivity and quality of the beet. The experimental design used was entirely randomized, in a 3 × 2 × 2 factorial scheme, referring to three doses of phosphate fertilization (25%, 50% and 100%), with and without the use of Trichoderma-based inoculation, and two levels of electrical conductivity of the irrigation water (0.5 and 6.2 dS m−1). Salt stress negatively affected the leaf area of the beet. The shoots’ dry mass was reduced as the electrical conductivity of the irrigation water increased, especially in the treatment with the 25% P2O5 dose. Salt stress reduced photosynthesis to a greater extent at the 25% P2O5 dose and in the absence of Trichoderma harzianum. Increasing the electrical conductivity of the irrigation water reduced transpiration and increased leaf temperature at the 25% P2O5 dose and in the presence of Trichoderma harzianum. The 25% P2O5 dose increased the stomatal conductance of the beet. The higher electrical conductivity of the irrigation water negatively affected water use efficiency, most significantly at the 25% P2O5 dose. Our data showed that the doses of 50% and 100% P2O5 were more efficient at increasing the productivity and quality of the beet, with the tuberous root diameter being higher under the lower electrical conductivity of the water and the absence of Trichoderma harzianum. The pH was high under the lowest electrical conductivity of the water, with a dose of 25% P2O5 and the absence of Trichoderma harzianum.

The deleterious effects of salts on plants exposed to high solar radiation tend to be more accelerated due to the increase of toxic ions in the aerial plant part. Consequently, the physiological and biochemical processes will be affected. These effects can be minimized, however, with the use of management strategies, such as the use of a shading screen and a protected environment. In this sense, the objective of this work was to evaluate the physiological responses of sugar beet cultivated in different environments and irrigated with saline water. The experiment was conducted in an experimental design entirely randomized, using the factorial scheme 3 × 2, equivalent to three environments (FS = full sun; SSOS = shading screen open on the sides and PE = protected environment) and two electrical conductivities of the irrigation water (0.5 and 6.2 dS m-1), with four repetitions. At 45 days after sowing (DAS) the following variables were analyzed: stomatal conductance, liquid photosynthesis, transpiration, internal CO2 concentration, leaf temperature, instantaneous water use efficiency, instantaneous carboxylation efficiency, intrinsic water use efficiency, and relative chlorophyll index. Irrigation with water of higher salinity negatively affected stomatal conductance, net photosynthesis, leaf temperature and instantaneous water use efficiency of sugar beet plants grown in a full sun environment. The protected environment and open shading on the sides partially mitigated the deleterious effects of salinity.

Resumo Apresenta-se os resultados de um experimento de cultivo de Palma Forrageira Orelha de Elefante (Opuntia stricta Haw) nas condições climáticas observadas na região Jaguaribana, região semiárida do Estado do Ceará. O experimento foi instalado em uma área de 480,0 m2 (0,048 ha) na Comunidade Riachão, localizada na zona rural do município de Jaguaribe-CE (5°47'15” S e 38°32'29” W), composto por vinte parcelas distribuídas em blocos casualizados com o uso de biofertilizante de esterco bovino em cinco tratamentos distintos, parcela de controle (sem uso do biofertilizante) e quatro doses que variaram 0,5 a 2,0 L, com quatro aplicações a partir do quadragésimo dia de plantio com intervalos de quinze dias até os cem dias de plantio. Os resultados mostraram que quatro das variáveis avaliadas apresentaram correlação estatística positiva entre a aplicação do biofertilizante e o desenvolvimento das plantas, e que as variáveis comprimento, largura e espessura dos cladódios, obtiveram os melhores resultados com a aplicação de doses de 2,0 L, obtendo valores médios de 22,27 cm, 16,47 cm, e 0,87 cm, respectivamente. Assim, concluiu-se que o cultivo desta cultura, com o uso de biofertizante de esterco bovino, pode auxiliar na criação dos rebanhos da região e mitigar os efeitos negativos causados pela falta de pastagem em períodos secos que são consequências da variabilidade climática observada na região.

The fava bean crop makes an important socioeconomic contribution to the Northeast region of Brazil. However, in this region, there is a quantitative and qualitative shortage of water, being necessary the use of brackish water for irrigation. This study aimed to evaluate the saline stress on the yield and water-use efficiency in fava bean crop cultivated under monoculture and intercropping systems. The experiment was conducted under field conditions, using a randomized blocks experimental design, in a 5 x 2 factorial arrangement, with four replications. The first factor corresponded to five levels of electrical conductivity of irrigation water (1.0, 2.0, 3.0, 4.0 and 5.0 dS m-1) and the second comprised two cropping systems: fava bean grown in monoculture and intercropped with corn. The salt stress negatively affected the number of pods in the intercropped system, but with less intensity. The increase of salts in the irrigation water reduces the pod length, diameter and mass, as well as the yield and water-use efficiency, while the monoculture system is less affected by these effects.

ABSTRACT Peanut cultivation in the northeast of Brazil has been badly affected by salts accumulating in the irrigation water; in this respect, the use of plant mulch is one way of mitigating salt stress. The aim of this study was to evaluate the effect of irrigation using brackish water under different mulching strategies on productivity and water use efficiency in the peanut. The experiment was carried out under field conditions in Redenção, in the state of Ceará, in a randomised block design of split-plots with five replications, in which the plots corresponded to two levels of electrical conductivity of the irrigation water (0.8 and 4.0 dS m-1), and the subplots to six mulching strategies based on the phenology of the crop (MS1: mulch throughout the cycle; MS2: flowering stage; MS3: appearance of the gynophore; MS4: pod formation; MS5: final flowering stage; MS6: no mulch). The following were determined at the end of the experimental cycle: commercial, non-commercial and total number of pods, number of grains per pod, pod length and diameter, productivity and water use efficiency. Irrigation with lower-salinity water, together with mulching during the phenological stages of the peanut, affords better productive performance and greater water use efficiency. Salt stress reduced the length and diameter of the pods and had a negative effect on productivity and water use efficiency, both with and without the use of plant mulch during the phenological stages.

In Brazil, the lima bean bean is cultivated throughout almost the entire country, and has relative economic importance in the Northeast, which is the main producer. Increasing the availability of K via fertilisation, would increase the productivity of the lima bean. Therefore, the aim of this study was to evaluate different doses of potassium on productivity in the lima bean. The study was carried out in the field between January and July 2019, in the town of Raposa, Baturité, Ceará. The experimental design was of randomised blocks, with five treatments and four replications. The treatments consisted of the following doses of potassium: 60, 90, 120, 150 and 180 kg ha-1 K2O, using potassium chloride as a source, corresponding to 50%, 75%, 100%, 125% and 150% of the recommended dose. As the pods dried and the grain was collected, the following variables were evaluated: number of pods per plant, pod length, pod diameter, pod weight and productivity. The potassium doses of 130, 109 and 180 kg ha-1 K2O afforded the greatest number of pods (124), pod weight (108.64g) and pod diameter (18 mm), respectively. The dose of 106.20 kg ha-1 K2O, lower than the recommended dose for the lima bean, determined the maximum grain yield, 1,567 kg ha-1.

ABSTRACT Inferior quality water can be used by agricultural producers in arid and semi-arid regions due to the lower availability of good-quality water. Therefore, the objective was to identify the influence of irrigation with saline water on gas exchange and leaf contents in corn (Zea mays L.) crop. The work was conducted in the field, in the experimental area of the Experimental Farm of the University of International Integration of Afro-Brazilian Lusofonia (UNILAB), Redenção-CE. The experimental design used in the research was randomized blocks, with five treatments: 1.0; 2.0; 3.0; 4.0 and 5.0 dS m-1 and four repetitions. At 45 days after sowing (DAS) the gas exchange variables were evaluated: transpiration, stomatal conductance, photosynthesis, internal CO2 concentration, water use efficiency and leaf temperature. And at 110 DAS the contents of N, P, K, Ca and Mg in plant leaves. The saline stress due to saltwater irrigation leads to a reduction in photosynthesis, stomatal conductance, internal CO2 concentration and transpiration in field maize plants. Salt stress reduces the levels of N, P, K, Ca and Mg mineral elements in maize leaves.

The use of brackish water causes chemical changes in cultivated soils. It is therefore necessary to apply strategies that can minimize its negative impacts, such as the use of organic fertilizers. This study aimed to evaluate in the field the chemical attributes of a Red Yellow Argisol under irrigation with saline water and organic fertilizing in an area cultivated with corn. The design was randomized blocks, in a split-plot scheme, with the plots comprising salinity levels for the irrigation water (0.8 and 3.0 dS m-1) and the subplots combinations of organic fertilizers (cattle manure + poultry biofertilizer + goat biofertilizer; cattle manure + goat biofertilizer; cattle manure + poultry biofertilizer; control), with four replications. The 3.0 dS m-1 irrigation has a negative effect on the soil chemical attributes, particularly reducing the pH and increasing the sodium, exchangeable sodium percentage and electrical conductivity of the soil saturation extract. The combination of cattle manure + poultry biofertilizer + goat biofertilizer mitigates the salt stress by favouring the accumulation of nitrogen and organic matter, while the cattle manure + poultry biofertilizer favours the potassium accumulation in the soil. The combination of cattle manure + poultry biofertilizer + goat biofertilizer increases the contents of phosphorus and potassium when using the 0.8 dS m-1 irrigation.

O estresse salino prejudica o desenvolvimento inicial da cultura do amendoim. Contudo, seus efeitos possuem intensidade que dependem de outros fatores, como as espécies ou cultivar. Objetivou-se avaliar os efeitos do estresse salino no crescimento inicial de genótipos de amendoim. O experimento foi conduzido em estufa agrícola sob condições de vaso na Universidade da Integração Internacional da Lusofonia Afro-Brasileira em Redenção/CE. Os tratamentos foram: dois níveis de condutividade elétrica da água de irrigação (2,0 e 5,0 dS m-1); e cinco genótipos de amendoim (cultivar BR-1, Acesso 08, 28, 43 e 130). Foi implantado num esquema fatorial (2 × 5) sob delineamento inteiramente casualizado com cinco repetições. Aos 34 dias após a semeadura foram avaliadas as seguintes variáveis: número de folhas, altura de plantas, área foliar, diâmetro do caule, massa seca da parte aérea, condutividade elétrica do extrato de saturação do solo e o pH. A água de irrigação com condutividade de 5,0 dS m-1 reduz área foliar, altura de planta, diâmetro do caule, número de folhas e a matéria seca da parte aérea de genótipos de amendoim, cultivar BR-1, Acessos 08, 28, 43 e 130. Também eleva o pH e a condutividade elétrica do extrato de saturação, em relação à água de menor condutividade (2,0 dS m-1).

The use of plant-growth-promoting rhizobacteria (PGPR) can be one option for mitigating the impact of abiotic constraints on different cropping systems in the tropical semi-arid region. Studies suggest that these bacteria have mechanisms to mitigate the effects of water stress and to promote more significant growth in plant species. These mechanisms involve phenotypic changes in growth, water conservation, plant cell protection, and damage restoration through the integration of phytohormone modulation, stress-induced enzyme apparatus, and metabolites. The aim of this study was to evaluate the growth, leaf gas exchange, and yield in maize (Zea mays L.—BRS Caatingueiro) inoculated with Bacillus aryabhattai and subjected to water and salt stress. The experiment followed a randomised block design, in a split-plot arrangement, with six repetitions. The plots comprised two levels of electrical conductivity of the irrigation water (0.3 dS m−1 and 3.0 dS m−1); the subplots consisted of three irrigation depths (50%, 75%, and 100% of the crop evapotranspiration (ETc)); while the sub-subplots included the presence or absence of B. aryabhattai inoculant. A water deficit of 50% of the ETc resulted in the principal negative effects on growth, reducing the leaf area and stem diameter. The use of B. aryabhattai mitigated salt stress and promoted better leaf gas exchange by increasing the CO2 assimilation rate, stomatal conductance, and internal CO2 concentration. However, irrigation with brackish water (3.0 dS m−1) reduced the instantaneous water-use efficiency of the maize. Our results showed that inoculation wiht PGPR mitigates the effect of abiotic stress (salt and water) in maize plants, making it an option in regions with a scarcity of low-salinity water.

O objetivo do presente estudo foi investigar os acessos de feijão-fava mais e menos tolerantes ao estresse salino em função das trocas gasosas foliares. O experimento foi conduzido em ambiente protegido em um delineamento experimental inteiramente casualizado (DIC), em esquema fatorial 5 x 4, referentes a cinco condutividades elétricas da água de irrigação - CEa: 1,0; 2,0; 3,0; 4,0 e 5,0 dS m-1, e quatro variedades de fava (Branquinha – C1, Manteiguinha – C2, Espírito Santo – C3 e Orelha-de-vó – C4), com quatro repetições. Aos 35 dias após a semeadura (fase vegetativa) coletaram-se dados da condutância estomática (gs), fotossíntese (A), transpiração (E), eficiência instantânea do uso da água (A/E), concentração intercelular do CO2 (Ci) e temperatura foliar (Tl). Os sais afetaram negativamente as trocas gasosas das variedades de fava. Os graus de redução na taxa de fotossíntese indicam as variedades C1 e C3, respectivamente, com maior e menor capacidade tolerar o estresse salino.

This work evaluated the effects of water salinity on the physiological indices in inoculated and non-inoculated peanut plants. The study was carried out in a protected environment at the seedling production unit (UPMA) at Campus das Auroras, at the University for International Integration of the Afro-Brazilian Lusophony (UNILAB), Redenção, Ceará. The experimental design used was in a completely randomized (CRD), with treatments in a factorial arrangement, 5x2, referring to the five salinity levels of the irrigation water - CEa: 0.5, 1.5, 3, 4.5, and 6.0 dSm-1, and inoculated and non-inoculated plants with a mix of rhizobia SEMIA 630, lot 0810, and SEMIA 6144, lot 0312, from Bradyrhizobium sp., isolated, with four replications. Recommended fertilization was done for phosphorus (62.5 kg ha-1 of P) and potassium (50 kg ha-1 of K) to supply the nutritional needs of the plants. The nutritional effect caused by symbiosis with Bradyrhizobium sp. favored inoculated plants to present greater tolerance to salt stress. The availability of nitrogen collaborated to increase the efficiency of plant physiological mechanisms. Uninoculated plants, even with a higher amount of chlorophyll and CO2, were not efficient in the photosynthetic rate. Saline stress affected photosynthesis, transpiration, stomatal conductance, internal CO2 concentration, water use efficiency, and chlorophyll; however, with less intensity when inoculated with Bradyrhizobium sp. The increase in salinity on irrigation water increased the leaf temperature.

Abstract The Climatological Water Budget (CWB) determined by the Thornthwaite and Matter (1955) allows the temporal visualization of the variables that compose the climate, thus allowing the climatic characterization of a region. Therefore, this work aimed at identifying and quantifying the months of water surplus and deficit through CWB to characterize the climate for the municipality of Cruzeiro do Sul - AC, Brazil, and analyze the temporal distribution of rainfall for the municipality. We used daily precipitation and temperature values and procedures to fill in the database. We calculated the potential evapotranspiration (ETP) using the Hargreaves Samani method (1985). Subsequently, we determined the periods of soil water storage (SWS), water deficiency (DEF), and water surplus (SUR) on a monthly scale. The climate of Cruzeiro do Sul, located in the northern region of Brazil, was characterized according to the Thornthwaite (1955) as B1rA'a' for a AWC of 140 mm, that is, a humid climate with annual rainfall average of 2227 mm and real evapotranspiration of 1660 mm, with small water deficiency in the months from June to October, with no thermal deficiency, and summer concentrated in three months with an average air temperature of 25 °C ranging between 18 °C and 32 °C.

Objetivou-se avaliar o crescimento inicial e os teores foliares de macronutrientes em plantas de quiabo (Abelmoschus esculentus L.) em função de diferentes doses e tipos de biofertilizantes. O experimento foi conduzido na fazenda experimental Piroás da Universidade da Integração Internacional da Lusofonia Afro-Brasileira (Unilab), no município de Redenção (CE). O delineamento experimental utilizado foi inteiramente casualizado, em esquema fatorial 5 x 2, referente a cinco doses de biofertilizante (0,0; 0,5; 1,0; 1,5 e 2,0 L planta-1 semana-1) e a dois tipos de biofertilizante (bovino e caprino). Foram analisadas as variáveis: altura de planta (AP), área foliar (AF), número de folhas (NF), diâmetro do caule (DC) e teores foliares de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca) e magnésio (Mg). O incremento das doses de biofertilizante contribuiu de forma positiva nas variáveis AP, AF, NF e DC. O insumo bovino foi mais eficiente quando comparado ao caprino para as variáveis AF e NF. O teor de N nas folhas foi elevado com o incremento das doses de biofertilizante. O fertilizante caprino promoveu um maior conteúdo de K nas folhas quando comparado ao bovino. Com a elevação das doses dos biofertilizantes bovino e caprino, os teores foliares de P, Mg e Ca foram reduzidos.

The objective of this research was to define the potential of brackish groundwater for 15 systems of biosaline agriculture in a representative area of the Brazilian semi-arid region. The study was conducted using a database of the State of Ceará, with 6284 wells having brackish water (EC ≥ 0.8 dS m−1 and discharge rate ≥ 0.5 m3 h−1). Our results show that the potential of brackish groundwater resources depends on the set of data: (i) production system (crop salt tolerance and water demand) and (ii) water source (salinity and well discharge rate). The joint analysis of these data shows that plant production systems with lesser water requirements, even with moderate tolerance levels to salt stress, present better results than more tolerant species, including halophytes and coconut orchards. About 41, 43, 58, 69, and 82% of wells have enough discharge rates to irrigate forage cactus (1.0 ha), sorghum (1.0 ha with supplemental irrigation), hydroponic cultivation, cashew seedlings, and coconut seedlings, respectively, without restrictions in terms of salinity. Otherwise, 65.8 and 71.2% of wells do not have enough water yield to irrigate an area of 1.0 ha with halophytes and coconut palm trees, respectively, butmore than 98.3 and 90.7% do not reach the water salinity threshold for these crops. Our study also indicates the need for diversification and use of multiple systems on farms (intercropping, association of fish/shrimp with plants), to reach the sustainability of biosaline agriculture in tropical drylands, especially for family farming.

As leguminosas podem ser eficientes para aumentar os teores de carbono (C) e nitrogênio (N) no solo. Com base nisso, objetivou-se com o presente estudo selecionar plantas leguminosas com o maior potencial para acumular C e N no solo. O experimento foi conduzido em 2018, em Redenção, Ceará. O delineamento experimental adotado foi em blocos casualizados, com oito tratamentos e três repetições. Os tratamentos correspondem a: controle (solo sem cobertura vegetal), palha, mucuna preta, mucuna cinza, lablab, feijão-guandu, crotalária e feijão-de-porco. No florescimento (aos 67 dias após a semeadura), as leguminosas foram cortadas e deixadas sobre a área. Aos 78 dias após o corte, amostras de solo foram coletadas nas camadas de 0-5 e 5-10 cm para determinação da densidade do solo (Ds) e de partículas (Dp), porosidade total (Pt), carbono orgânico total (COT), estoques de carbono (EstC) e nitrogênio (EstN), nitrogênio total (NT) e a relação de carbono com nitrogênio (C:N). As plantas de cobertura não alteraram Ds, Dp, Pt, NT e a relação C:N, em razão da textura arenosa do solo e curto período experimental. Porém, contribuíram para o aumento dos teores de COT. As plantas leguminosas são capazes de aumentar o estoque de carbono do solo mesmo em curto prazo. A mucuna cinza é a planta leguminosa com maior potencial para acumular C no solo. No entanto, para manutenção de resíduo orgânico no solo é recomendado o uso de Crotalaria juncea.

ABSTRACT Proper management of brackish water can increase plant production in the Brazilian semi-arid region. The objective of this study was to evaluate the production performance and water use efficiency of two peanut genotypes irrigated with brackish water during the reproductive stage, in soil with and without soil cover. The study was conducted in a greenhouse. The experimental design used was randomized blocks, with four replicates, in a 2 x 2 x 2 factorial scheme (two electrical conductivities of irrigation water - ECw 0.9 and 5.0 dS m-1, two peanut genotypes - AC 130 and cv. BR1, and the presence or absence of soil cover). At 72 days after sowing, harvest was performed and the following variables were evaluated: number of marketable pods, number of non-marketable pods, pod mass, diameter and length, production and water use efficiency. Salinity impacted production more than the water use efficiency in the two peanut genotypes, with the relative reduction in production being higher in cv. BR-1. Soil cover with dead plant material mitigated the effects of salinity on production and increased water use efficiency, only in genotype AC 130.

Resumo Das espécies do gênero Phaseolus, a fava é a mais tolerante à seca se comparada com os feijões comuns. Apesar da sua importância, ela tem sido pouco estudada, necessitando de pesquisas aplicadas à cultura para maior compreensão dos mecanismos envolvidos na resposta ao déficit hídrico. Este estudo avalia a tolerância de quatro genótipos de fava cultivados no Ceará quanto a sua resistência ao estresse hídrico. O experimento foi realizado em um delineamento inteiramente casualizado, no esquema fatorial 4 x 3 em que o primeiro fator foi constituído pelos genótipos: ‘Branca’, ‘Mulatinha’, ‘Preta’ e ‘Coquinho Laranja’; o segundo por três regimes hídricos: irrigado, déficit moderado e déficit severo; com cinco repetições. As plantas foram conduzidas em vasos até o estádio fenológico V3 onde foram avaliados os seguintes parâmetros fisiológicos: taxa fotossintética (A), condutância estomática (gs), relação Ci/Ca, Transpiração (E), eficiência no uso da água (EUA), eficiência no uso da água intrínseca (EUA int), eficiência instantânea de carboxilação (EiC) e taxa de transferência de elétrons (ETR). Sem comprometer seu metabolismo, o genótipo Coquinho Laranja foi mais tolerante ao déficit hídrico, evidenciando maior produtividade fotossintética, associadas à alta eficiência no uso da água pelo fechamento dos seus estômatos com redução da transpiração.

Resumo Este estudo apresenta uma análise da produção agrícola e suas relações com as secas no Ceará na produção agrícola de milho (Zea mays L.), feijão-caupi (Vigna unguiculata L. Walp.) e mandioca (Manihot esculenta Crantz), para o período de 1987-2016. Foram analisadas as variáveis de produção, rendimento e área plantada dessas culturas acompanhados de dados estatísticos, como médias, desvios padrões e coeficientes de variação desses cultivos. Uma ênfase foi dada ao período concomitante de secas entre 2011-2016. Foram coletados dados de precipitação diária (acumulados de 24 horas) em 220 pluviômetros no estado do Ceará, a variabilidade pluviométrica, expressa pelo cálculo de períodos de estiagens (menor ou igual a 2 mm.dia-1 entre 01 de fevereiro e 31 de maio) chamados de veranicos, que estão associados a esses anos de secas e às características de produção e rendimentos das culturas de sequeiro. No período analisado neste estudo (1987-2016) verificou-se influência direta das anomalias de chuva sobre a produtividade das culturas estudadas, pela incidência de veranicos, com destaque para os anos de 2011 a 2016.

O biofertilizante pode atenuar o efeito do estresse salino no crescimento inicial e na fisiologia do feijão-caupi (Vigna unguiculata). O objetivo deste trabalho foi avaliar o efeito do biofertilizante bovino no crescimento inicial e trocas gasosas de plantas de feijão-caupi irrigadas com água salina. O experimento foi conduzido em condição de campo na Horta Didática do campus da Liberdade na Universidade da Integração Internacional da Lusofonia Afro-Brasileira, Redenção, Ceará. A cultivar “BRS Tumucumaque” foi utilizada no experimento, sendo semeada em vasos plásticos de 8 litros, em delineamento de blocos ao acaso sob esquema fatorial 5x2, com quatro repetições, sendo o primeiro fator composto por cinco concentrações de biofertilizantes (5, 10, 15, 20 e 25% do volume do vaso e o segundo fator composto pela condutividade elétrica da água de irrigação (CEa: 0,5 e 5,0 dS m-1). A área foliar, número de folhas, diâmetro do caule, altura das plantas, condutância estomática, taxa de fotossíntese e transpiração foram avaliadas. O estresse salino reduziu a altura de plantas, transpiração e fotossíntese. A concentração de 15% de biofertilizante bovino foi a mais eficiente para atenuar o uso da água de alta salinidade para o número de folhas, diâmetro do caule, área foliar e a condutância estomática.

Zucchini culture is slightly sensitive to salinity and is among the ten vegetables of highest economic value, with characteristics of precocity and easy cultivation. These characteristics are some of the reasons for the expansion of its cultivation among small producers. Thus, the objective was to evaluate the effect of different levels of salinity in the irrigation water and biofertilizer types on the initial growth of the zucchini (Cucurbita pepo L.) culture. The experiment was carried out in the full sunlight in a randomized block design, in a 5x2 factorial arrangement. The treatments consisted of a combination of five types of biofertilizers (quail, sheep, mixed, bovine, and crab) and two salinity levels of the irrigation water (0.8 and 2.5 dS m-1), with five replicates. At 30 days after transplanting, the following variables were evaluated: electrical conductivity of the substrate, plant height, number of leaves, roots length, stem diameter, leaf area, chlorophyll content, dry mass of the aerial part, root dry mass, and total dry mass. Salt stress negatively interferes with the accumulation of zucchini plant biomass. Quail, bovine, and sheep biofertilizers are more efficient about plant height, number of leaves, and stem diameter. The sheep biofertilizer attenuates the salt stress for the dry mass of the aerial part, the root, and the total dry mass.

A salinidade e a deficiência hídrica são fatores abióticos com forte impacto sobre as atividades agrícolas, especialmente, em regiões áridas e semiáridas. Objetivou-se com a pesquisa analisar a tolerância de dois genótipos de sorgo forrageiro, EA 116 e BRS Ponta Negra, a diferentes níveis de estresse hídrico e salino durante a germinação. As condições de estresse hídrico e salino foram simuladas a partir do umedecimento do substrato com solução de manitol e Cloreto de Sódio (NaCl), respectivamente, com potencial hídrico ajustadas em: 0 (água destilada); -0,1; -0,2; -0,3; -0,4; -0,5 e -0,6 MPa. As variáveis analisadas foram Porcentagem de germinação, primeira contagem, índice de velocidade de germinação, comprimento da parte aérea e radicular, massa seca da plântula, extravasamento de eletrólitos e a relação Na+/K+ das folhas. Conduzido em delineamento inteiramente casualizado, distribuídos em esquema de fatorial 2 (genótipos) × 2 (condição de estresse) × 7 (potencial osmótico), com quatro repetições. Os genótipos EA 116 e BRS Ponta Negra apresentam maior tolerância ao estresse hídrico. A cultivar EA 116 manteve a germinação em condições de estresse hídrico de 0 a -0,6 MPa e salina de 0 a -0,4 MPa.

Mineral fertilization promotes good results for the components of production and quality of okra fruit; however, it raises the cost of production, making it, sometimes, unviable to the small producers. Thus, this study aimed to evaluate organic and mineral fertilization in different forms, in the components of production, productivity, and quality of okra fruits. The experiment was carried out, under full sunlight, in a completely randomized design (CRD), with six replications. The treatments corresponded to the different forms of fertilization, being: MF = mineral fertilization with NPK (100% of the recommended dose); BF = fertilization with bovine biofertilizer (100% of the NPK contents); VA = fertilization with vegetable ash (100% of NPK contents); MFBF = mineral fertilizer (50%) + bovine biofertilizer (50%); MFVA = mineral fertilizer (50%) + vegetable ash (50%); C = control (without fertilization). The variables analyzed were as follows: number of fruits per plant (NFP), average fruit mass (AFM), fruit length (FL), fruit diameter (FD), fruit skin thickness (FST), and yield (Y). Therefore, the use of bovine biofertilizer in isolation or supplemented with mineral fertilization enhances the production of okra and improves the quality of the fruits, reveling as promising alternatives for growing okra.

The objective of this study was to evaluate the effect of different doses of bovine biofertilizer on yield and post harvest of the strawberry crop in different growing environments. The experiment was carried out in two cycles of production, in Fortaleza, Ceará. The experimental design was in randomized blocks, arranged in subdivided plots, where the plots were of three cultivated environments (A1 = protected environment with screens, cold-water spraying, and white floor; A2 = environment with full sun, cold-water spraying, and white floor; A3 = environment with full sun, no cold-water spraying, and grey floor). The subplots consisted of five doses of biofertilizer (D1 = 0,0, D2 = 500, D3 = 750, D4 = 1000 and D5 = 1250 mL plant-1 week -1), with five replications. In the two-year period, the dose was higher in the protected environment of the weed type, with nebulization and on the white floor, at the dose of 500 mL week-1 plant-1 in the first cycle and 325 mL week-1 plant-1 in the second cycle. The dose of bovine biofertilizer of 1250 mL week-1 plant-1 promotes a longer duration and duration of the first cycle. During the second cycle, as the bovine biofertilizer doses of 585 and 620 provide higher and lower output than the protected environment. The environment without nebulization and on the floor without painting, the best soluble practices (Brix) in relation to the protected environment of the type screened and a full sun with nebulization.

Organic fertilization, associated to cultivation under a climatized environment, can make profitable the growth of strawberry plants in the Brazilian Northeast region, increasing the market value for their fruits. This study aimed to evaluate the effect of organic and/or mineral fertilization on strawberry plants grown under different environments. The experiment was carried out in a complete split-plot randomized block design, with four replications. The plots were composed by three cultivation environments and the subplots by six types of fertilization, associating mineral and organic fertilization. The organomineral fertilization with equal proportions of bovine manure and NPK mineral fertilizer provides a higher number of fruits per plant, average fruit mass per plant, yield and fruit length. There was no significant difference among the evaluated environments; however, in general, the climatized environment provides greater results, regarding the development and quality of the plants, improving the physicochemical characteristics of the fruits.

Objetivou-se avaliar o crescimento inicial do morangueiro irrigado com águas salinas em solo com e sem biofertilizante bovino. O experimento foi conduzido em ambiente protegido na Estação Agrometeorológica, Ciências Agrárias, da Universidade Federal do Ceará, Fortaleza, no período de setembro a outubro de 2016. O delineamento experimental foi inteiramente casualizado seguindo o esquema fatorial 5 x 2, com cinco repetições. O primeiro tratamento foi constituído pelos níveis de condutividade elétrica da água de irrigação, sendo: 0,5 dS m-1; 1,0 dS m-1; 1,5 dS m-1; 2,0 dS m-1 e 2,5 dS m-1, e o segundo tratamento compreendeu duas condições: sem e com biofertilizante bovino. Foram avaliadas as seguintes variáveis: número de folhas, comprimento da raiz, matéria seca da parte aérea, da raiz e total e condutividade elétrica. A salinidade da água de irrigação afetou o número de folhas, área foliar, comprimento da raiz, massa seca da parte aérea, da raiz e total, porém com menor intensidade em solo com biofertilizante bovino, demonstrando que o insumo atenua os efeitos da salinidade no crescimento do morangueiro.

O entendimento da dinâmica da matéria orgânica e dos nutrientes no dejeto suíno submetido à biodegradação anaeróbia é importante por auxiliar nas tomadas de decisão para a utilização do biofertilizante anaeróbio como fertilizante agrícola. Nesse sentido, desenvolveu-se um estudo, utilizando reatores anaeróbios de bancada, com o objetivo de avaliar as mudanças na matéria orgânica, através da quantificação do carbono nas frações húmicas e oxidáveis, e nas formas orgânicas e inorgânicas de fósforo da fração sólida do dejeto suíno, em função do tempo de biodegradação. Realizaram-se avaliações nos seguintes tempos de retenção hidráulica: 7, 14, 21, 28, 35, 42 e 49 dias de biodegradação e os resultados comparados com o dejeto não degradado. As mudanças na matéria orgânica ocorreram em suas frações mais lábeis (C-ácido fúlvico e fração F1) com redução dos seus conteúdos, favorecendo o acúmulo de frações mais recalcitrantes no biofertilizante final (C-ácido húmico e frações F2, F3 e F4). O conteúdo total de P não sofreu mudanças ao longo do processo. No entanto, a fração inorgânica de P extraível em água reduziu em 16,7 % após 49 dias de biodegradação, sendo consumida pela microbiota decompositora para a formação de matéria orgânica estabilizada, que se acumula, juntamente com as frações mais recalcitrantes de P no biofertilizante final. O uso do biofertilizante anaeróbio suíno possui, portanto, menor risco de contaminação ambiental pelo excesso de P do que a aplicação direta do dejeto in natura no solo.

Banana farming is an activity of great economic and social importance, and is carried out in most tropical countries. The aim of this work was to evaluate the biomass accumulation and levels of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) in micropropagated plants of the banana “Prata Catarina” during the acclimatization phase, under different types and doses of biofertilisers. The experimental design included randomised blocks in a 2 × 5 + (2) factorial scheme, with two types of liquid biofertilisers (bovine biofertiliser with anaerobic and aerobic fermentation) and five biofertiliser doses (0.25, 0.50, 0.75, 1.00, and 1.25 L plant-1 week-1), as well as two additional treatments (control and recommended mineral fertilisation). The following variables were analysed: dry weight of the leaves and roots, and mineral element content (N, P, K, Ca, and Mg) in different parts of the plant (leaf and root). During 90 days of acclimatization, the nutritional contribution of bovine biofertiliser with anaerobic fermentation was greater in comparison with the biofertiliser with aerobic fermentation and the control, but lower in comparison with mineral fertilisation. The 1000-mL dose of the biofertiliser with anaerobic fermentation promoted greater dry weight accumulation in the leaves and roots of the banana “Prata Catarina”. The biofertiliser with anaerobic fermentation promoted higher levels of N, K, and Ca in the leaves, whereas the biofertiliser with aerobic fermentation promoted higher levels of P in the leaves and roots.

The objective was to evaluate the productivity of the fig tree the organic fertirrigation cattle under different environmental conditions in Ceará semiarid region. The experiment was conducted in the experimental area of the Teaching Unit, Research and Extension, the IFCE, North Lemon Tree, EC. The experimental design was a randomized complete block design with split plots, with four replications and three plants per plot. The plots consisted of three rooms (full sun - PS; trellis - LT and greenhouse - EST), the subplots, the concentrations of bovine biofertilizer diluted in water in the following concentrations: T0 (0% of biofertilizer + 100% water); T1 (20% biofertilizer 80 +% water); T2 (40% biofertilizer + 60% water), T3 (60% biofertiliante + 40% water) and subsubplot, the production cycles. The variables were evaluated: average fruit weight, fruit diameter, number of fruits per plant and yield. The cultivation environments (greenhouse and trellis) promote better performance on average mass and diameter of the fruit compared to plants grown in full sun during the production cycles of the fig crop grown in Ceará semiarid region. The bovine biofertilizer in the concentration of 60% promoted the highest mass, diameter, number of fruits per plant and the fig crop yield.

As plantas respondem diferenciadamente aos efeitos dos sais nas distintas fases do seu ciclo. No entanto, o uso de condicionantes orgânicos pode atenuar o efeito do estresse salino sobre o crescimento das plantas. Este trabalho teve como objetivo avaliar o efeito do estresse salino no crescimento inicial de plantas de girassol cultivadas em substratos com diferentes fertilizantes orgânicos. O trabalho foi conduzido na área experimental da Estação Agrometeorológica da Universidade Federal do Ceará, em Fortaleza, no período de setembro a novembro de 2013. O delineamento experimental empregado foi inteiramente casualizado, em um esquema fatorial 4 x 2, referente aos substratos (S1 = areia + arisco + composto orgânico; S2 = areia + arisco + biofertilizante de caranguejo; S3 = areia + arisco + biofertilizante bovino de fermentação aeróbia; S4 = areia + arisco + biofertilizante bovino de fermentação anaeróbia), com duas condutividades elétricas da água de irrigação (0,8 e 5,0 dS m-1), com 5 repetições. Foram analisadas as seguintes variáveis: número de folhas, diâmetro do caule, área foliar e altura de plantas, matéria seca da parte aérea, da raiz e total. O S3 e o S4 proporcionam maior altura de planta e área foliar nas plantas irrigadas com água de baixa salinidade. As plantas cultivadas com o S3 e S4 apresentaram maiores valores em número de folhas, diâmetro do caule, matéria seca da parte aérea, da raiz e total. Palavras-chave: Helianthusannuus L. Estresse salino. Condicionantes orgânicos.

The use of organic fertilizer from animal waste can mitigate the harmful effects of salinity of irrigation water on the plants. This experiment was performed in the experimental area of the Universidade Federal do Ceará, Weather Station (Estação Meteorológica), from September to November 2012, aiming at evaluate the response of the cowpea (Vigna unguiculata L.) to salinity levels and biofertilizer types in a greenhouse. The experimental design was that of completely randomized, 5x3 factorialwith five replications. The first factor consisted of electrical conductivity of irrigation water levels, as follows: 0.8 dS m-1; 1.5 dS m-1; 3.0 dS m-1; 4.5 dS m-1 and 6.0 dS m-1; and the second factor comprised three conditions: without biofertilizers (B0), with enriched crabbio fertilizer (B1) and with bovine common biofertilizer (B3). The evaluated variables were: photosynthesis, leaf temperature, transpiration, stomatal conductance, plant height, stem diameter, number of leaves, leaf area, and shoot dry mass. The crab enriched biofertilizer more efficiently mitigates the salt stress on plant height, stem diameter, number of leaves, leaf area, photosynthesis, transpiration and stomatal conductance of cowpea cultivar BRS ITAIM compared to plants with biofertilizer and biofertilizer bovine common. The biofertilizer of crab enriched more efficiently mitigates the salt stress on plant height, stem diameter, number of leaves, leaf area, photosynthesis, transpiration and stomatal conductance of cowpea cultivar BRS ITAIM compared to plants without biofertilizer and bovine common biofertilizer. = O uso de fertilizantes orgânicos provenientes de resíduos de origem animal pode atenuar os efeitos danosos da salinidade da água de irrigação sobre as plantas. Um experimento foi conduzido na área experimental da Estação Agrometeorológica da Universidade Federal do Ceará, Fortaleza, Ceará, no período de setembro a novembro de 2012, objetivando-se avaliar a resposta do feijão-caupi a níveis de salinidade, sem e com dois tipos de biofertilizantes em casa de vegetação. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 5x3, com cinco repetições. O primeiro fator consistiu dosníveis de condutividade elétrica da água de irrigação, sendo:0,8 dS m-1; 1,5 dS m-1; 3,0 dS m-1; 4,5 dS m-1 e 6,0 dS m-1; e o segundo fator compreendeu três condições: sem biofertilizante (B0), com biofertilizante de caranguejo enriquecido (B1) e com biofertilizante bovino comum (B3). Foram avaliadas as seguintes variáveis: fotossíntese, temperatura da folha, transpiração, condutância estomática, altura de plantas, diâmetro do caule, área foliar e matéria seca da parte aérea. O biofertilizante de caranguejo enriquecido atenua com mais eficiência o estresse salino sobre a altura das plantas, diâmetro do caule, número de folhas, área foliar, fotossíntese, transpiração e condutância estomática do feijão-caupi cultivar BRS ITAIM em relação às plantas sem biofertilizante e com biofertilizante bovino comum.

This study was conducted to evaluate the effect of different irrigation frequencies on growth, gas exchange and yield of the peanut (Arachis ypogea L). The experiment was conducted in the field using the experimental design of randomized blocks with five treatments, five replications with four plants per plot. The treatments were composed: F2 = (irrigation every 2 days), F4 = (irrigation every 4 days), F6 = (irrigation every 6 days), F8 = (irrigation every 2 days) and F10 = (irrigation every 10 days). At 60 days after sowing (DAS), the gas exchange variables (photosynthesis, stomatal conductance and transpiration) and growth variables (plant height, leaf number, stem diameter and shoot dry matter) were evaluated. The highest irrigation frequency tested (every two days) promoted the best results for plant growth (leaf number, plant height, shoot dry matter) e for leaf gas exchange. The highest yield of field grown peanuts at the conditions prevailing in Fortaleza, Ceará, is associated with the adoption of an irrigation frequency interval of two days.

The bovine biofertilizer applied through irrigation water in the soil (bio fertigation), can be a viable organic source to maintain fertility levels in agricultural production systems. So, this work was aimed at evaluating the effects of different concentrations of bovine biofertilizer applied by fertigation on corn growth, gas exchange and yield. The experiment was conducted under full sun exposure, in Fortaleza, Ceara, in 100 liter (100 L) vessels. The experimental design was that of randomized blocks with five treatments and five repetitions. Treatments consisted of 0.5 L doses (per plant) of a fertigating solution (biofertilizer + water) weekly applied, with a different biofertilizer concentration to each treatment, as follows: C0 = 0% biofertilizer (control), C1 = 12.5%, C2 = 25% biofertilizer, C3=50% biofertilizer, C4 = 100% biofertilizer. We analyzed the effects on the following variables: plant height, stem diameter, leaf number, shoot dry weight, photosynthesis, stomatal conductance, transpiration and yield. The biofertilizer was the most efficient considering the initial growth and gas exchange. Also, the bovine biofertilizer treatments (as a whole) favored the increase in the weight of 1000 seeds and grain yield.

http://dx.doi.org/10.5902/1980509812347This paper evaluated the biometry of fruits, seeds and seedling emergence of Amburana cearensis (Allemão)AC Smith derived from fruits with different stages of coloring and drying. Fruits of red color, dark andclosed and the ground seeds were collected after dehiscence of the fruit. At each stage of maturation, length,width and thickness of fruits and seeds were measured. Then, we proceeded to the descriptive analysis.To test the emergency four replicates of 25 seeds were seeded and distributed in a completely randomizeddesign with factorial [(2 x 2 + 1)] and two fruit colors (red and dark) and two drying conditions (with andwithout ) and an additional (seeds collected on the ground after dehiscence). The evaluation was done bydetermining: the percentage, index of speed and average time of emergency, and measuring the height andshoot dry matter of the seedling. Considering the results, it was found that red and black fruits and theirseeds of Amburana cearensis have different biometric characteristics and the drying process favors theemergence percentage, but had no positive effect on height and shoot dry matter.

The potassium irrigation management and fertigation adjustment may improve grape yield and quality. Aiming at evaluating the biometric and productive characteristics of the 'Ribier' grapevine, under five irrigation levels (50%, 75%, 100%, 125% and 150% of the class A pan evaporation - CAE) and five potassium fertilization doses (2, 4, 6, 8 and 10 days), applied by fertigation, two experiments were carried out in a randomized blocks design, with five treatments and five replications, in Limoeiro do Norte, Ceará State, Brazil. The variables bunch number, size and average weight, soluble solids and yield were evaluated for the five irrigation levels, while the bunch average weight and width, number of berries, soluble solids and yield were evaluated for the five potassium fertigation intervals. The maximum irrigation level (150% of the CAE) and the seven days interval for the potassium fertigations provided the best yield for the 'Ribier' grapevine, under the Ceará State semiarid conditions.

This paper evaluated the biometry of fruits, seeds and seedling emergence of Amburana cearensis (Allemão) AC Smith derived from fruits with different stages of coloring and drying. Fruits of red color, dark and closed and the ground seeds were collected after dehiscence of the fruit. At each stage of maturation, length, width and thickness of fruits and seeds were measured. Then, we proceeded to the descriptive analysis. To test the emergency four replicates of 25 seeds were seeded and distributed in a completely randomized design with factorial [(2 x 2 + 1)] and two fruit colors (red and dark) and two drying conditions (with and without ) and an additional (seeds collected on the ground after dehiscence). The evaluation was done by determining: the percentage, index of speed and average time of emergency, and measuring the height and shoot dry matter of the seedling. Considering the results, it was found that red and black fruits and their seeds of Amburana cearensis have different biometric characteristics and the drying process favors the emergence percentage, but had no positive effect on height and shoot dry matter.

Objetivou-se com esse trabalho avaliar o efeito da salinidade da água de irrigação nas características agronômicas do amendoinzeiro (Arachis hypogaea L.) cultivado em solo sem e com biofertilizantes. O experimento foi conduzido em estufa telada na Estação Agrometereológica, Campus do Pici, Fortaleza, CE. A semeadura foi feita em vasos utilizando-se, como substrato, um Argissolo Vermelho-Amarelo, com uma planta por vaso. O experimento obedeceu a um delineamento inteiramente casualizado, em esquema fatorial 4 x 3, com cinco repetições. Os fatores referem-se aos valores de condutividadeelétrica da água de irrigação: 1,5; 3,0; 4,5 e 6,0 dS m-1 e sem e com biofertilizantes (sem biofertilizante -B0; com biofertilizanteanaeróbico-B1; e com biofertilizante aeróbico - B2). Foram avaliadas as seguintes variáveis: pH, condutividade elétrica do solo, crescimento inicial em número de folhas, altura de plantas, diâmetro do colmo, área foliar e matéria seca da parte aérea. O biofertilizante bovino diminuiu os efeitos negativos das concentrações crescentes de sais na água de irrigação nas variáveis estudadas. O nível salino do solo foi maior na presença do biofertilizante anaeróbico. O biofertilizante anaeróbico foi mais eficiente que o aeróbico na redução dos efeitos depressivos dos sais das águas de irrigação às plantas.This study evaluated the effects of irrigation water salinity on agronomics characteristics of peanut (Arachis hypogaea L.), cultivated without and with biofertilizers. The experiment was conducted in a greenhouse in the Estação Agrometereológica, Campus do Pici, Fortaleza, CE. The seeds were sown in pots using, as substrate, a Red-Yellow Argisol, with one plant per pot. The experiment followed a completely randomized design set as a 4 x 3 factorial, referring to four irrigation water electrical conductivity values: 1.5, 3.0, 4.5 and 6.0 dS m-1 in three soil configurations: B0(without biofertilizer), B1 (with anaerobic biofertilizer) and B2 (with aerobic biofertilizer), with five repetitions. The following variables were evaluated: pH, soil electrical conductivity, initial growth in number of leaves, plant height, stem diameter, leaf area and dry shoot mass. The bovine biofertilizer reduced the negative effects of increasing saline concentration in irrigation water in the variables evaluated.The soil salinity level was higher in the presence of anaerobic biofertilizer. The anaerobic biofertilizer was more efficient thanaerobic biofertilizer in reducing the depressive effects (to plants) of irrigation water salts.

O objetivo deste trabalho foi avaliar o efeito da irrigação com água de alta e baixa salinidade sob o crescimento inicial de plantas de milho cultivadas em solo adubado com biofertilizante bovino. O experimento foi conduzido em ambiente telado do Departamento de Ciências do Solo - UFC. O plantio das sementes deu-se em vasos com capacidade de 12 kg, contendo como substrato um Argissolo e uma planta por vaso. O experimento obedeceu a um delineamento experimental inteiramente casualizado, em esquema fatorial 5 x 2, com quatro repetições, referentes a cinco concentrações de biofertilizante: C1 = 50% bio + 50% água (1:1), C2 = 33,33% bio + 66,67 água (1:2), C3 = 25% bio + 75% água (1:3), C4 = 20% bio + 80% água (1:4) e C5 = 11,12+ 88,88% água (1:5) e dois níveis de salinidade para a água de irrigação S1 = 0,8 dS m-1 (baixa salinidade) e S2 = 3,4 dS m-1 (alta salinidade). Foram analisadas a condutividade elétrica do solo (CEes) e o crescimento inicial das plantas utilizando-se as seguintes características: altura de plantas, diâmetro do colmo, área foliar, matéria seca da parte aérea, da raiz e matéria seca total. A irrigação com água de baixa salinidade foi mais eficiente no crescimento inicial das plantas, exceto a matéria seca da raiz, sob concentrações crescentes de biofertilizante bovino. Sob as mesmas concentrações de biofertilizante bovino e irrigação com água salina, elevou o caráter salino do solo, mas com menos intensidade no solo irrigado com água de baixa salinidade.The purpose of this study was to evaluate the effect of irrigation with water of high and low salinity on the initial growth of corn plants grown in soil fertilized with bovine bio-fertilizer. The experiment was conducted in a greenhouse of the Department of Soil Science - UFC. The seeds were planted in vessels with a 12 kg capacity, containing Alfissol as substrate and one plant per pot. The experiment followed a completely randomized design, in a 5x2 factorial scheme, with four replications, referring to five concentrations of bio-fertilizer: C1 = 50% biofertilizer + 50% water (1:1), C2 = 33.33% biofertilizer + 66.67 + water (1:2), C3 = 25% biofertilizer + 75% water (1:3), C4 = 20% biofertilizer + 80% water (1:4) and C5 = 11.12% biofertilizer + 88, 88% water (1:5) and two salinity levels of irrigation water for S1 = 0.8 dS m-1 (low salinity) and S2 = 3.4 dS m-1 (high salinity). We analyzed the early growth of plants as compared to the readings of electrical conductivity of water saturated soil extracts (ECse) by using the collected data on plant height, stem diameter, leaf area, shoot dry matter, root dry matter and total dry matter. Irrigation with low salinity water was found more efficient in promoting the initial growth of plants under increasing concentrations of biofertilizer, except for root dry matter. Under the same concentrations of biofertilizer, plus irrigation with saline water, soil salinity increased, but did so with less intensity in soil irrigated with low salinity water.

O objetivo deste trabalho foi avaliar a influência da irrigação com água de alta e baixa salinidade sobre variáveis microbiológicas do solo em área submetida à rotação de cultura entre milho (Zea Mays L.) e feijão-de-corda (Vigna unguiculata L.). A área destinada ao experimento foi dividida em duas subáreas, sendo realizados quatro cultivos: dois cultivos irrigados na estação seca e dois de sequeiro na estação chuvosa. O estudo foi conduzido em campo, utilizando-se o delineamento em blocos ao acaso, com cinco repetições. Nos cultivos irrigados foram usadas água com as seguintes condutividades elétricas (CEa): 0,8; 2,2; 3,6 e 5,0 dS m-1. Os cultivos de sequeiro foram realizados nas mesmas parcelas que foram cultivadas na estação seca, as quais permaneceram demarcadas e identificadas. No início e ao final de cada cultivo, foram coletadas amostras em duas subáreas na região radicular das plantas, no terço médio da fileira central de cada parcela. O aumento da salinidade da água de irrigação promoveu aumento do número total de esporos de fungos micorrízicos arbusculares FMA e reduziu a respiração basal do solo, o carbono da biomassa e o coeficiente metabólico microbiano (qCO2), principalmente na área cultivada com feijão-de-corda. O gênero Glomus respondeu por mais de 70% dos esporos totais encontrados, sendo que essa percentagem aumentou nos tratamentos com maior salinidade nos cultivos da estação seca. Os dados não evidenciaram qualquer efeito negativo da salinidade residual sobre as variáveis microbiológicas avaliadas, em função da irrigação com água salina durante os cultivos da estação seca.This work carred out the influence of irrigation with water of high and low salinity on soil microbial variables in area under the crop rotation between maize (Zea Mays L.) and cowpea (Vigna unguiculata L.). The area for the experiment was divided into two sub areas being made four crops, two crops irrigated in the dry season and two dry in the rainy season. The study was conducted under field conditions using a randomized block design with five replications. In irrigated crops were used the following water with electrical conductivity (ECw): 0.8; 2.2; 3.6 and 5.0 dS m-1. The rainfed crops were conducted on the same plots that were cultivated during the dry season, which remained demarcated and identified. At the beginning and end of each crop were collected samples in two subareas in the region of root system plant, in the middle third of the central row of each plot. Increasing of salinity in irrigation water led to increase in the total number of spores and reduced soil basal respiration, biomass carbon and microbial metabolic coefficient (qCO2), mainly in the area cultivated with cowpea. The genus Glomus accounted for more than 70% of total spores found, and this percentage increased in treatments with high salinity in dry season crops. The data reveal no residual negative effect of salinity on the microbial variables assessed in function irrigation with saline water during the dry season crops.

Este experimento foi executado no Centro de Ciências Agrárias da UFPB,Areia, Estado da Paraíba, com objetivo de avaliar a fertilidade de substratos compostos por diferentes concentrações de fibra de coco (0 a 40%), esterco bovino (0 a 25%), terra vegetal (25 a 70%), 15% de areia e adubados com superfosfato triplo (0; 5,5 e 11 g L-1). Houveaumento das características químicas desejáveis do substrato com aumento da concentração de terra vegetal, fibra de coco e dose máxima do superfosfato triplo. A fibra de coco provocou aumento do teor de sódio nos substratos. Recomenda-se utilizar o substratoconstituído de 0 % de esterco, 46% de terra vegetal, 39% de fibra de coco, 15% de areia e 11 g L-1 de superfosfato triplo para obtenção dos máximos valores estimados de matéria orgânica, potássio, magnésio, cálcio e fósforo, e mínimo para H++Al+3 e sódio.This experiment was carried out at Centro de Ciências Agrárias of UFPB, Areia, state of Paraíba, whose objective was to evaluate thefertility of the substrata composed by concentrations of coconut fiber from 0 to 40%, manure bovine from 0 to 25.5%, soil from 25 to 70%, sand 15% and triple superphosphate between 0 and 11 g L-1. There was increase of the desirable chemical characteristics to thesubstratum with the increase of the concentration of soil, coconut fiber and maximum dose of the triple superphosphate. The coconut fiber increased the tenor of sodium in the substrata. It is recommended to use the concentrations of 0% of manure, 46% of soil, 39% of coconut fiber, 15% of sand and 11 g L-1 of triple superphosfate, to obtain the maxima estimated values of organic matter, potassium, magnesium, calcium and phosphorus, andminima for H++Al+3 and sodium.

O uso de fertilizantes orgânicos provenientes de resíduos de origem animal pode atenuar os efeitos danosos da salinidade da água de irrigação sobre as plantas. Um experimento foi conduzido na área experimental da Estação Agrometeorológica da Universidade Federal do Ceará, Fortaleza, Ceará, no período de setembro a novembro de 2012, objetivando-se avaliar a resposta do feijão-caupi a níveis de salinidade, sem e com dois tipos de biofertilizantes em casa de vegetação. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 5x3, com cinco repetições. O primeiro fator consistiu dosníveis de condutividade elétrica da água de irrigação, sendo:0,8 dS m-1; 1,5 dS m-1; 3,0 dS m-1; 4,5 dS m-1 e 6,0 dS m-1; e o segundo fator compreendeu três condições: sem biofertilizante (B0), com biofertilizante de caranguejo enriquecido (B1) e com biofertilizante bovino comum (B3). Foram avaliadas as seguintes variáveis: fotossíntese, temperatura da folha, transpiração, condutância estomática, altura de plantas, diâmetro do caule, área foliar e matéria seca da parte aérea. O biofertilizante de caranguejo enriquecido atenua com mais eficiência o estresse salino sobre a altura das plantas, diâmetro do caule, número de folhas, área foliar, fotossíntese, transpiração e condutância estomática do feijão-caupi cultivar BRS ITAIM em relação às plantas sem biofertilizante e com biofertilizante bovino comum.

RESUMO: Um experimento foi desenvolvido no período de janeiro a maio de 2008, em condições de campo, na área experimental da estação experimental da CAGECE/PROSAB/CT-UFC, localizada no município de Aquiraz, CE, para avaliar a produtividade da cultura da mamoneira sob diferentes fontes e doses de nitrogênio. O experimento obedeceu a um delineamento inteiramente casualizado, em esquema fatorial 5 x 3, referente as doses de nitrogênio: 0 kg ha-1; 30 kg ha-1; 50 kg ha-1; 70 kg ha-1 e 90 kg ha-1 versus três fontes de adubação nitrogenada (uréia, nitrato de amônio e sulfato de amônio), com cinco repetições. Aos 120 dias após a semeadura (DAS),as plantas foram coletadas e avaliadas as seguintes variáveis: altura do 1º racemo, número de racemo, comprimento do racemo, número de frutos por plantas e produtividade. A aplicação de nitrogênio aumenta o número de racemo, número de frutos e o comprimento do racemo da mamoneira aos 120 dias após a semeadura (DAS), independentemente da fonte utilizada. A aplicação de nitrogênio aumenta a produtividade da cultura da mamona irrigada com água de esgoto doméstico tratado, com a fonte ureia na dose de 76,41 kg ha-1 (1156,67 kg ha-1), na fonte sulfato amônio a dose de 57,95 kg ha-1 proporciona uma produtividade de 1491,68 kg ha-1 e para a fonte nitrato de amônio a dose de 108,08 kg ha-1 evidencia uma produtividade de 1925,41 kg ha-1.

O mamoeiro é uma planta herbácea que possui como principais características, seu rápido desenvolvimento e sua fácil propagação. Este experimento objetivou avaliar o crescimento de mudas de mamoeiro em substratos contendo diferentes concentrações de caulim. O experimento foi realizado no Viveiro de Fruticultura do Departamento de Fitotecnia, do Centro de Ciências Agrárias, da Universidade Federal da Paraíba, localizado no município de Areia – PB. O delineamento experimental utilizado foi em blocos ao acaso, com 11 tratamentos; constituídos por misturas de esterco (20 a 60%), solo (20 a 60%), caulim (0 a 30%) e 10% de areia, e três repetições. A unidade experimental foi constituída de quatro sacos contendo uma muda cada. As sementes foram semeadas em sacos de polietileno, com capacidade de 1 litro. Determinaram-se a altura e o diâmetro das mudas aos 42; 62 e 83 dias após a emergência inicial das sementes. A massa da matéria seca da parte aérea e do sistema radicular das mudas foi avaliada aos 83 dias após a emergência inicial das sementes. O rejeito de caulim promoveu aumento inicial do crescimento das mudas de mamoeiro com decréscimo a partir de concentrações superiores a 22%. Para obter o máximo crescimento do sistema radicular e da parte aérea das mudas recomenda-se o substrato constituído por 22% de rejeito de caulim, 29% de terra, 39% de esterco e 10% de areia.

Este experimento foi executado no Centro de Ciências Agrárias da UFPB, Areia, Estado da Paraíba, com objetivo de avaliar a fertilidade de substratos compostos por diferentes concentrações de fibra de coco (0 a 40%), esterco bovino (0 a 25%), terra vegetal (25 a 70%), 15% de areia e adubados com superfosfato triplo (0; 5,5 e 11 g L-1). Houve aumento das características químicas desejáveis do substrato com aumento da concentração de terra vegetal, fibra de coco e dose máxima do superfosfato triplo. A fibra de coco provocou aumento do teor de sódio nos substratos. Recomenda-se utilizar o substrato constituído de 0 % de esterco, 46% de terra vegetal, 39% de fibra de coco, 15% de areia e 11 g L-1 de superfosfato triplo para obtenção dos máximos valores estimados de matéria orgânica, potássio, magnésio, cálcio e fósforo, e mínimo para H++Al+3 e sódio.

ABSTRACT Strawberry is produced and appreciated in different regions of the world, due to its productive and commercial characteristics. Biofertilizer is an organic fertilizer that is easy to prepare and effective to nourish plants. The objective of this work was to assess the effect of different irrigation levels and anaerobically fermented bovine biofertilizer doses, on biomass accumulation and strawberry crop yield. The experiment was carried out in the experimental area of the UFC, in Fortaleza, Ceará, Brazil, from August to December 2012, under a screened environment. The experimental design was randomized blocks designed into subdivided plots, in which irrigation levels were applied via drip irrigation (equivalent to 33.3, 66.6, 100, 133.3 and 166.6% of the evaporation measured in the Class A tank - ECA), corresponding to the plots. The four doses of bovine biofertilizer (125, 250, 375 and 500 mL plant-1 week-1) were the subplots, with four replications. The assessed parameters were: biomass (root, shoot and total dry matter), fruit diameter, fruit length, number of fruits per plant, average fruit mass and yield. The biofertilizer and irrigation increased strawberry shoot biomass and total biomass. The interaction between irrigation and bovine biofertilizer raised the root matter to 3.7 g. The biofertilizer was nutritionally efficient for the strawberry regarding number of fruit, fruit diameter and yield. Irrigation increased strawberry length and average mass.

This study was conducted to evaluate the effect of different irrigation frequencies on growth, gas exchange and yield of the peanut (Arachis ypogea L). The experiment was conducted in the field using the experimental design of randomized blocks with five treatments, five replications with four plants per plot. The treatments were composed: F2 = (irrigation every 2 days), F4 = (irrigation every 4 days), F6 = (irrigation every 6 days), F8 = (irrigation every 2 days) and F10 = (irrigation every 10 days). At 60 days after sowing (DAS), the gas exchange variables (photosynthesis, stomatal conductance and transpiration) and growth variables (plant height, leaf number, stem diameter and shoot dry matter) were evaluated. The highest irrigation frequency tested (every two days) promoted the best results for plant growth (leaf number, plant height, shoot dry matter) e for leaf gas exchange. The highest yield of field grown peanuts at the conditions prevailing in Fortaleza, Ceará, is associated with the adoption of an irrigation frequency interval of two days.