ABSTRACT The permanence of sugarcane straw on the soil surface, in systems without the pre-harvest straw burning practice, directly affects the soil organic matter dynamics. The objective of this work was to evaluate the changes in total organic carbon (TOC), carbon in the light organic matter (CLOM) and particulate organic carbon (POC), and their carbon stocks in a typic Quartzipsamment cultivated for nine years with sugarcane crops, which were conducted without the pre-harvest straw burning practice, in Paraipaba, State of Ceará, Brazil. Disturbed and undisturbed soil samples were collected at depths of 0.0-0.025, 0.025-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.30 m, in the sugarcane crop area and in an adjacent native forest area, in order to quantify the TOC, CLOM and POC, as well as the carbon stocks accumulated in the layer 0.0-0.30 m related to these fractions (TOCSt, CLOMSt and POCSt). TOC content changes after nine years of sugarcane crops, conducted without pre-harvest straw burning, were found only in the layers 0.10-0.20 and 0.20-0.30 m. The CLOM varied only in the layer 0.025-0.05 m. The POC content changes were more noticeable than the changes in TOC and CMOL. The CLOM of the sugarcane crop area presented high similarity with TOC, which may affect their quantification in studies related to the soil organic matter dynamics. The sugarcane crop increased the TOCSt, POCSt and CLOMSt in the layer 0.0-0.30 m, compared with the adjacent native forest area. | RESUMO A permanência da palhada da cana-de-açúcar sobre a superfície do solo no sistema sem queima do canavial tem influência direta na dinâmica da matéria orgânica desses solos. Objetivou-se com este estudo avaliar as mudanças ocorridas nos conteúdos de carbono orgânico total (COT), carbono da matéria orgânica leve (CMOL) e carbono orgânico particulado (COP) e em seus respectivos estoques de carbono em um Neossolo Quartzarênico após nove anos de cultivo com cana-de-açúcar sem queima prévia do canavial em Paraipaba-CE. Foram coletadas amostras de solo deformado e indeformado nas profundidades de 0,0 - 0,025; 0,025 - 0,05; 0,05 - 0,10; 0,10 - 0,20 e 0,20 - 0,30 m em uma área sob cultivo de cana-de-açúcar e em uma área de mata nativa adjacente, quantificando-se os teores de COT, CMOL e COP, assim como os valores de estoques de carbono acumulados na camada de 0 - 0,30 m associados a essas frações: EstCOT, EstCMOL e EstCOP. Mudanças no conteúdo de COT após nove anos de cultivo de cana-de-açúcar sem queima foi observado apenas nas camadas de 0,10 - 0,20 e 0,20 - 0,30 m. Já o CMOL apresentou variação apenas para a camada de 0,025 - 0,05 m. As mudanças ocorridas no conteúdo de COP foram mais perceptíveis do que no conteúdo de COT e CMOL. O CMOL na área de cana apresentou uma elevada similaridade com o COT, o que pode tornar inviável sua quantificação em estudos para inferir sobre a dinâmica da matéria orgânica em solos. O cultivo de cana-de-açúcar aumentou o EstCOT, o EstCOP e o EstCMOL na camada de 0 - 0,30 m em comparação a área de mata nativa adjacente.

The permanence of sugarcane straw on the soil surface, in systems without the pre-harvest straw burning practice, directly affects the soil organic matter dynamics. The objective of this work was to evaluate the changes in total organic carbon (TOC), carbon in the light organic matter (CLOM) and particulate organic carbon (POC), and their carbon stocks in a typic Quartzipsamment cultivated for nine years with sugarcane crops, which were conducted without the pre-harvest straw burning practice, in Paraipaba, State of Ceará, Brazil. Disturbed and undisturbed soil samples were collected at depths of 0.0-0.025, 0.025-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.30 m, in the sugarcane crop area and in an adjacent native forest area, in order to quantify the TOC, CLOM and POC, as well as the carbon stocks accumulated in the layer 0.0-0.30 m related to these fractions (TOCSt, CLOMSt and POCSt). TOC content changes after nine years of sugarcane crops, conducted without pre-harvest straw burning, were found only in the layers 0.10-0.20 and 0.20-0.30 m. The CLOM varied only in the layer 0.025-0.05 m. The POC content changes were more noticeable than the changes in TOC and CMOL. The CLOM of the sugarcane crop area presented high similarity with TOC, which may affect their quantification in studies related to the soil organic matter dynamics. The sugarcane crop increased the TOCSt, POCSt and CLOMSt in the layer 0.0-0.30 m, compared with the adjacent native forest area.

RESUMO O potássio (K) é um nutriente essencial para o crescimento do arroz, no entanto existem poucas informações sobre os efeitos do K no crescimento radicular e na capacidade de absorção de nutrientes por diferentes cultivares de arroz de terras altas. Um experimento foi conduzido em casa de vegetação para avaliar a influência de diferentes níveis de K no solo no crescimento radicular e absorção de nutrientes de quatro cultivares de arroz de terras altas. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 4x4, (4 níveis de K: 20, 40, 80 e 160 mg dm-3; 4 cultivares: Caiapó, BRS-Primavera, IAC-202 e Maravilha), com quatro repetições. Com base nas equações de regressão, o maior valor para comprimento radicular seria obtido com aplicação de 136 mg dm-3 de K. O diâmetro e a matéria seca radicular, a concentração de K e a biomassa da parte aérea aumentaram linearmente com o aumento das doses de K, porém a concentração de K na parte aérea não diferiu entre as cultivares de arroz. O aumento do nível de K no solo reduziu a concentração Ca na parte aérea das cultivares dos grupos intermediário e moderno, mas a concentração de Mg reduziu em todas as cultivares. A adubação potássica aumentou o desenvolvimento das plantas, variando de acordo com o genótipo. | ABSTRACT Potassium (K) is an essential nutrient for upland rice growth, but little information on the effects of K on root growth and nutrient uptake capacity of upland rice is found. Therefore, an experiment was conducted under greenhouse conditions to evaluate the influence of soil K levels on root growth and nutrient uptake of four upland rice cultivars. A completely randomized experimental design, in a 4x4 factorial scheme (4 levels of K: 20, 40, 80, and 160 mg dm-3; 4 cultivars: Caiapó, BRS-Primavera, IAC-202, and Maravilha) was used, with four replications. Based on regression equations, the highest values of root length density would be found with 136 mg dm-3 of K. The root diameter and dry matter, shoot dry matter and shoot K concentration increased linearly with the increasing K rates. The shoot K concentration of the upland rice cultivars did not differ. The increased level of K in the soil reduced the shoot Ca concentration of intermediate and modern cultivars, and the shoot Mg concentration of all cultivars. The potassium fertilization increased the plant growth, but the magnitude of this effect varied according to the cultivar.

Potassium (K) is an essential nutrient for upland rice growth, but little information on the effects of K on root growth and nutrient uptake capacity of upland rice is found. Therefore, an experiment was conducted under greenhouse conditions to evaluate the influence of soil K levels on root growth and nutrient uptake of four upland rice cultivars. A completely randomized experimental design, in a 4x4 factorial scheme (4 levels of K: 20, 40, 80, and 160 mg dm-3; 4 cultivars: Caiapó, BRS-Primavera, IAC-202, and Maravilha) was used, with four replications. Based on regression equations, the highest values of root length density would be found with 136 mg dm-3 of K. The root diameter and dry matter, shoot dry matter and shoot K concentration increased linearly with the increasing K rates. The shoot K concentration of the upland rice cultivars did not differ. The increased level of K in the soil reduced the shoot Ca concentration of intermediate and modern cultivars, and the shoot Mg concentration of all cultivars. The potassium fertilization increased the plant growth, but the magnitude of this effect varied according to the cultivar..

ABSTRACT Passiflora cincinnata Mast. has become more popular in the market because the unusual flavor of its fruits and natural beauty of its flowers, and has great potential for breeding programs of Passiflora edulis f. flavicarpa, because its resistance to diseases and drought. The objective of this work was to evaluate seven wild passion fruit (P. cincinnata) accessions, using morphological and agronomic descriptors and molecular markers type ISSR, to identify their morphoagronomic and genetic variabilities and potential for use in breeding programs. A randomized block experimental design was used with five replications and two plants per plot. Thirteen qualitative and twenty-one quantitative, vegetative and floral characteristics were used for morphoagronomic characterization. Twelve ISSR primers were evaluated for molecular characterization. Among the qualitative characteristics, only the color variations were significantly different between the accessions. According to the mean squares of the quantitative characteristics evaluated, obtained from analysis of variance, the means of accessions showed significant differences (p<0.01) for all characteristics. The IAL (internode average length) was the morphological descriptor that most contributed to diversity, with 43.12%, followed by DH5 (stem diameter at 5 cm height) and SW (sepal width). The average genetic similarity found was 68%. Despite the low genetic variability found among accessions, the primers UBC-887 and UBC-841 stood out with high percentage of polymorphism with 14 and 11 polymorphic fragments, respectively, and higher values of polymorphism information content (PIC), resolving power (RP) and marker index (MI), denoting suitability for use in diversity studies of P. cincinnata. Low variability was found among accessions evaluated. | RESUMO A espécie Passiflora cincinnata Mast. vem se popularizando no mercado pelo sabor incomum dos seus frutos, beleza natural de sua flores e possui grande potencial para a cultura de Passiflora edulis f. flavicarpa, pois apresenta resistência a doenças e déficit hídrico. Este trabalho teve como objetivo avaliar sete acessos de maracujá-do-mato (P. cincinnata) por meio de descritores morfológicos, descritores agronômicos e marcadores moleculares do tipo ISSR visando identificar variabilidade morfoagronômica e genética e o potencial para serem utilizados em programas de melhoramento. O delineamento experimental foi em blocos casualizados, com cinco repetições e duas plantas por parcela. Para caracterização morfoagronômica foram avaliadas 13 características qualitativas e 21 características quantitativas vegetativas e florais. Para caracterização molecular foram testados 12 primers de ISSR. Entre as características qualitativas apenas as variações de coloração apresentaram diferenças marcantes entre os diferentes acessos. De acordo com os quadrados médios obtidos das análises de variância para as características quantitativas avaliadas pode-se ressaltar as diferenças significativas (p<0,01) entre as médias dos acessos para todos os caracteres avaliados. Verificou-se que para os 21 descritores morfológicos avaliados, o que mais contribuiu para a diversidade foi o MI (média internódio) com 43,12%, seguido por DH5 (diâmetro das hastes a 5 centímetros do solo) e LS (largura da sépala). A similaridade genética média encontrada foi 68%. Apesar de ser diagnosticada baixa variabilidade genética entre os acessos avaliados, os primers UBC-887 e UBC-841 se destacaram com alto percentual de polimorfismo, com 14 e 11 fragmentos polimórficos respectivamente e valores altos para conteúdo da informação de polimorfismo (PIC), poder de resolução do primer (RP) e índice do marcador (MI) dos primers, demonstrando aptidão para serem utilizados em pesquisas de diversidade em P. cincinnata. Foi diagnosticada baixa variabilidade entre os acessos avaliados.

Passiflora cincinnata Mast. has become more popular in the market because the unusual flavor of its fruits and natural beauty of its flowers, and has great potential for breeding programs of Passiflora edulis f. flavicarpa, because its resistance to diseases and drought. The objective of this work was to evaluate seven wild passion fruit (P. cincinnata) accessions, using morphological and agronomic descriptors and molecular markers type ISSR, to identify their morphoagronomic and genetic variabilities and potential for use in breeding programs. A randomized block experimental design was used with five replications and two plants per plot. Thirteen qualitative and twenty-one quantitative, vegetative and floral characteristics were used for morphoagronomic characterization. Twelve ISSR primers were evaluated for molecular characterization. Among the qualitative characteristics, only the color variations were significantly different between the accessions. According to the mean squares of the quantitative characteristics evaluated, obtained from analysis of variance, the means of accessions showed significant differences (p<0.01) for all characteristics. The IAL (internode average length) was the morphological descriptor that most contributed to diversity, with 43.12%, followed by DH5 (stem diameter at 5 cm height) and SW (sepal width). The average genetic similarity found was 68%. Despite the low genetic variability found among accessions, the primers UBC-887 and UBC-841 stood out with high percentage of polymorphism with 14 and 11 polymorphic fragments, respectively, and higher values of polymorphism information content (PIC), resolving power (RP) and marker index (MI), denoting suitability for use in diversity studies of P. cincinnata. Low variability was found among accessions evaluated.

ABSTRACT The selectivity of five insecticides, regularly used in peach farming, was assessed for larvae of the predator Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) by means of bioassay in semi-field conditions. The bioassay was based on the counting of captured larvae after release in peach trees treated with the insecticides (% of active ingredient in spray liquid): deltamethrin (0.001), fenthion (0.050), phosmet (0.100), lufenuron (0.005) and malathion (0.200). Bait-cards with eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) were used to capture larvae from treated plants; five of them were fixed in plant canopy and five others left on the soil around stem. A protective barrier made up of galvanized steel sheet was used for each plant to avoid loss of larvae. The number of larvae feeding on the bait-cards was measured for four days. According to the number of captured larvae, each insecticide effect was estimated and classified into toxicity categories as stated by the International Organization for Biological and Integrated Control of Noxious Animals and Plants (IOBC). Based on observations, the insect growth regulator lufenuron was harmless, while the neurotoxins deltamethrin and malathion were slightly harmful; and lastly, fenthion and phosmet were moderately harmful to C. externa larvae in semi-field conditions. Thus, lufenuron should be recommended for integrated pest management, since it would preserve this predator species in peach orchards. | RESUMO A seletividade de cinco inseticidas utilizados em pomares de pessegueiro foi avaliada sobre larvas do predador Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) por meio de bioensaio conduzido em semicampo. O bioensaio baseou-se na contagem do número de larvas capturadas após liberação em plantas de pessegueiro tratadas com os inseticidas (% de ingrediente ativo na calda) deltametrina (0,001), fentiona (0,050), fosmete (0,100), lufenurom (0,005) e malationa (0,200). Para captura das larvas nas plantas tratadas foram utilizados dez cartões-isca contendo ovos de Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae), sendo cinco fixados na copa e cinco fixados no solo ao redor do caule. Uma barreira de proteção composta por chapa de aço galvanizado foi utilizada em cada planta para evitar a perda de larvas. O número de larvas alimentando-se nos cartões foi mensurado durante quatro dias. Em função do número de larvas capturadas, o efeito de cada inseticida foi calculado e classificado nas categorias de toxicidade segundo a “International Organization for Biological and Integrated Control of Noxious Animals and Plants” (IOBC). Baseado no efeito observado, o regulador de crescimento lufenurom foi inofensivo, enquanto os neurotóxicos deltametrina e malationa foram pouco tóxicos, e fentiona e fosmete foram moderadamente tóxicos a larvas de C. externa em condições de semicampo. Desta forma, lufenurom deve ser recomendado no manejo integrado de pragas a fim de se preservar esta espécie de predador em pomares de pessegueiro.

The selectivity of five insecticides, regularly used in peach farming, was assessed for larvae of the predator Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) by means of bioassay in semi-field conditions. The bioassay was based on the counting of captured larvae after release in peach trees treated with the insecticides (% of active ingredient in spray liquid): deltamethrin (0.001), fenthion (0.050), phosmet (0.100), lufenuron (0.005) and malathion (0.200). Bait-cards with eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) were used to capture larvae from treated plants; five of them were fixed in plant canopy and five others left on the soil around stem. A protective barrier made up of galvanized steel sheet was used for each plant to avoid loss of larvae. The number of larvae feeding on the bait-cards was measured for four days. According to the number of captured larvae, each insecticide effect was estimated and classified into toxicity categories as stated by the International Organization for Biological and Integratec Control of Noxious Animals and Plants (IOBC). Based on observations, the insect growth regulator lufenuron was harmless, while the neurotoxins deltamethrin and malathion were slightly harmful; and lastly, fenthion and phosmet were moderately harmful to C. externa larvae in semi-field conditions. Thus, lufenuron should be recommended for integrated pest management, since it would preserve this predator species in peach orchards.

RESUMO Com o objetivo de avaliar os efeitos de doses de biofertilizante bovino na produção e qualidade e frutos um experimento foi conduzido no município de Nova Floresta, PB, em delineamento de blocos ao acaso, com três repetições e três plantas por parcela, adotando o esquema fatorial 3G x 5B, referente a três genótipos: Genótipo Local (Guinezinho) e dois híbridos, o BRS Sol do Cerrado e BRS Gigante Amarelo e cinco doses de biofertilizante bovino (B) aplicados mensalmente em volume constante de 5 L planta-1, após diluído em água de irrigação (A) de condutividade elétrica 1,4 dS m-1 nos níveis percentuais de 0% (água de irrigação - 0B + 5A), 10% (1B + 9A), 20% (2B + 8A), 30% (3B + 7A) e 40% (4B + 6A). Semanalmente os frutos foram colhidos, contados e pesados para obtenção do número de frutos por planta, produção por planta, e produtividade. No pico da produção, foram colhidos ao acaso, dois frutos por parcela da área útil, para determinação da massa média do fruto, casca e polpa (sementes + suco), espessura da casca, diâmetro e comprimento dos frutos. Além do rendimento em polpa, teor de sólidos solúveis, acidez titulável, vitamina C, valores de pH e da condutividade elétrica da polpa. A aplicação do biofertilizante não comprometeu a capacidade produtiva dos genótipos Guinezinho e Gigante Amarelo. As doses de biofertilizante proporcionaram características de qualidade aos frutos superiores às exigidas pelo mercado. | ABSTRACT This study aimed at evaluating the effects of bovine biofertilizer on passion fruit production and fruit quality. We carried out an experiment in the city of Nova Floresta, Paraíba State, Brazil. It was carried out in a randomized block design with three replications and three plants per plot. We adopted a 3 x 5 factorial scheme, which evaluated three passion fruit genotypes and five cattle biofertilizer doses. The assessed genotypes consisted of a local one (Guinezinho - LG) and two hybrids (BRS Gigante Amarelo - GA and BRS Sol do Cerrado - SC). We applied five rates of cattle biofertilizer (B) monthly at a constant volume of 5 L plant-1, after diluting in irrigation water (W) at an electrical conductivity of 1.4 dS m-1. The evaluated rates were 0% (100% irrigation water - 0B + 5W), 10% (1B + 9W), 20% (2B + 8W), 30% (3B + 7W) and 40% (4B + 6W). Every week, we sampled, counted and weighed fruit to gather data on fruit number per plant, pant production, and yield. At peak production, we also sampled two fruit randomly from each plot floor area. These fruits were used for determinations of the average mass in fruit, peel and pulp (seeds + juice), peel thickness, fruit diameter and length, pulp yield, soluble solid content, titratable acidity, vitamin C, pH and pulp electrical conductivity. As a result, we observed that the biofertilizer did not compromise both LG and GA production capacity. Overall, the biofertilizer doses provided quality characteristics superior to those required by the fruit market.

This study aimed at evaluating the effects of bovine biofertilizer on passion fruit production and fruit quality. We carried out an experiment in the city of Nova Floresta, Paraíba State, Brazil. It was carried out in a randomized block design with three replications and three plants per plot. We adopted a 3 x 5 factorial scheme, which evaluated three passion fruit genotypes and five cattle biofertilizer doses. The assessed genotypes consisted of a local one (Guinezinho - LG) and two hybrids (BRS Gigante Amarelo - GA and BRS Sol do Cerrado - SC). We applied five rates of cattle biofertilizer (B) monthly at a constant volume of 5 L plant-1, after diluting in irrigation water (W) at an electrical conductivity of 1.4 dS m-1. The evaluated rates were 0% (100% irrigation water - 0B + 5W), 10% (1B + 9W), 20% (2B + 8W), 30% (3B + 7W) and 40% (4B + 6W). Every week, we sampled, counted and weighed fruit to gather data on fruit number per plant, pant production, and yield. At peak production, we also sampled two fruit randomly from each plot floor area. These fruits were used for determinations of the average mass in fruit, peel and pulp (seeds + juice), peel thickness, fruit diameter and length, pulp yield, soluble solid content, titratable acidity, vitamin C, pH and pulp electrical conductivity. As a result, we observed that the biofertilizer did not compromise both LG and GA production capacity. Overall, the biofertilizer doses provided quality characteristics superior to those required by the fruit market.

ABSTRACT Knowledge of the interactions between soil physical properties and yield performance in agricultural crops is very important for the adoption of appropriate management practices. This study aimed to evaluate the linear and spatial correlations between some soil physical attributes, straw production in the palisade grass (Urochloa brizantha), and grain yield of winter common bean in succession to the grass under an irrigated no-till system in an Oxisol Haplorthox in the Cerrado lowlands region of Brazil. The plant attributes determined were dry matter yield of U. brizantha (DMY), and grain yield (GY) and final plant population (PP) of winter common bean. The soil physical attributes, evaluated at 0.0-0.10 m and 0.10-0.20 m, were soil bulk density (BD), macroporosity (MA), microporosity (MI), total porosity (TP), penetration resistance (PR), gravimetric water content (GW), and volumetric water content (VW). A geostatistical grid with 124 sampling points was installed to collect the soil and plant data in an area of 4000 m2. The remaining straw amount of palisade grass exhibited an inverse linear correlation with bean yield and bean plant population when the bean was cultivated in succession. However, no spatial correlations were observed among the attributes. The common bean yield had a direct linear correlation with gravimetric water content in the 0.10-0.20 m soil layer. From a spatial point of view, winter bean yield showed a strong dependence on the distribution of the volumetric water content in the 0-0.10 m soil layer. | RESUMO O conhecimento das interações entre os atributos físicos do solo e o desempenho produtivo das culturas agrícolas é de suma importância para a adoção de práticas de manejo adequadas. Deste modo, o presente estudo objetivou avaliar as correlações lineares e espaciais entre alguns atributos físicos do solo com a produção de palhada do capim-marandu (Urochloa brizantha) e a produtividade de grãos do feijoeiro de inverno cultivado em sucessão ao capim sob sistema plantio direto na região de Cerrado de baixa altitude, em condições irrigadas em um Latossolo Vermelho distroférrico. Os atributos das plantas foram: a produtividade de matéria seca (PMS) para a Urochloa brizantha, e para o feijoeiro a produtividade de grãos (PRO) e a população de plantas (PP). Os atributos físicos do solo avaliados nas camadas de 0,0-0,10 m e 0,10-0,20 m de profundidade foram: a densidade do solo (DS), macroporosidade (MA), microporosidade (MI), porosidade total (PT), resistência à penetração (RP), umidade gravimétrica (UG) e umidade volumétrica (UV). Para coleta dos dados foi instalada uma rede amostral contendo 124 pontos, em uma área de 4000 m2. A palhada remanescente do capim-marandu apresentou correlação linear inversa com os atributos do feijoeiro de inverno (população de plantas e a produtividade de grãos). Entretanto, sem correlação espacial sobre tais atributos. A produtividade de feijão teve correlação linear direta com a umidade gravimétrica do solo na camada de 0,10-0,20 m. Do ponto de vista espacial, a produtividade do feijoeiro de inverno apresentou forte dependência com a distribuição da umidade volumétrica na camada de 0-0,10m.

Knowledge of the interactions between soil physical properties and yield performance in agricultural crops is very important for the adoption of appropriate management practices. This study aimed to evaluate the linear and spatial correlations between some soil physical attributes, straw production in the palisade grass (Urochloa brizantha), and grain yield of winter common bean in succession to the grass under an irrigated no-till system in an Oxisol Haplorthox in the Cerrado lowlands region of Brazil. The plant attributes determined were dry matter yield of U. brizantha (DMY), and grain yield (GY) and final plant population (PP) of winter common bean. The soil physical attributes, evaluated at 0.0-0.10 m and 0.10-0.20 m, were soil bulk density (BD), macroporosity (MA), microporosity (MI), total porosity (TP), penetration resistance (PR), gravimetric water content (GW), and volumetric water content (VW). A geostatistical grid with 124 sampling points was installed to collect the soil and plant data in an area of 4000 m2. The remaining straw amount of palisade grass exhibited an inverse linear correlation with bean yield and bean plant population when the bean was cultivated in succession. However, no spatial correlations were observed among the attributes. The common bean yield had a direct linear correlation with gravimetric water content in the 0.10-0.20 m soil layer. From a spatial point of view, winter bean yield showed a strong dependence on the distribution of the volumetric water content in the 0-0.10 m soil layer.

RESUMO O nitrogênio (N) é o segundo nutriente mais demandado pela melancia e o que mais limita o seu crescimento e afeta a qualidade quando em deficiência. Foi avaliada a concentração de N no solo (N-nitrato), o teor de N na planta e sólidos solúveis da melancia 'Top Gun’ no Brasil, com seis doses de N (0, 50, 100, 150, 200 e 250 kg ha-1). Os valores de N-nitrato e N foliar aumentaram linearmente com as doses de N. Número de frutos total e comercial, massa de frutos total e comercial e produtividade total e comercial apresentaram efeito quadrático. A maior produtividade total e comercial foram obtidas com 187 e 184 kg ha -1 de N, respectivamente. As doses de N não influenciaram no teor de sólidos solúveis. | ABSTRACT Nitrogen (N) is the second most important nutrient required by watermelons that can limit their growth and affect fruit quality when deficient. We evaluated the soil (N-nitrate) and foliar N contents and soluble-solid content of the watermelon 'Top Gun' in Brazil at six rates of N fertilization (0, 50, 100, 150, 200 and 250 kg ha-1). N-nitrate and foliar N levels increased linearly with rate. Number of total and marketable fruit, weight of total and marketable fruit and total and marketable yields varied quadratically with rate. N rates of 187 and 184 kg ha-1 produced the highest total and marketable yields, respectively. The rate of N fertilization did not significantly affect total-solid content.

Nitrogen (N) is the second most important nutrient required by watermelons that can limit their growth and affect fruit quality when deficient. We evaluated the soil (N-nitrate) and foliar N contents and soluble-solid content of the watermelon 'Top Gun' in Brazil at six rates of N fertilization (0, 50, 100, 150, 200 and 250 kg ha-1). N-nitrate and foliar N levels increased linearly with rate. Number of total and marketable fruit, weight of total and marketable fruit and total and marketable yields varied quadratically with rate. N rates of 187 and 184 kg ha-1 produced the highest total and marketable yields, respectively. The rate of N fertilization did not significantly affect total-solid content.

RESUMO O objetivo do trabalho foi avaliar os efeitos da aplicação de gesso e vinhaça na produção de matéria seca, nutrição e atributos químicos do solo cultivado com alfafa. O experimento foi realizado em delineamento experimental de blocos ao acaso, em esquema fatorial 3 × 5, com três doses de vinhaça, 0, 150 e 300 m3 ha-1 e cinco doses de gesso agrícola (0, 3, 6, 9 e 12 Mg ha-1). Foram avaliados a composição química e matéria seca da parte aérea (MSPA) e os atributos químicos do solo (0-0,2 e 0,21-0,4 m). As doses de vinhaça aumentaram os teores de potássio, enquanto as doses de gesso promoveram acréscimos lineares nos teores de cálcio e enxofre no solo. A saturação de bases foi crescente e o magnésio teve efeito quadrático na camada de 0,21-0,4 m em função das doses de gesso. Os teores de cálcio, magnésio e fósforo na folha da alfafa foram menores com a aplicação de vinhaça. As doses de gesso promoveram acréscimos lineares na MSPA da alfafa. A dose de 150 m3 ha-1 já foi suficiente para aumentar a MSPA. Os teores de cálcio e magnésio na folha tiveram ajuste quadrático, com máximo acúmulo de cálcio em 9,5 Mg ha-1 e o magnésio com ponto de mínimo na dose de 8,7 Mg ha-1 de gesso. Os teores foliares de enxofre sob doses de vinhaça e os de potássio na maior dose obtiveram máximo acumulo na presença de 9 Mg ha-1 de gesso. | ABSTRACT The objective of this work was to evaluate the effects of the application of phosphogypsum and vinasse on soil chemical properties and productivity and nutritional characteristics of alfalfa (Medicago sativa). The experiment was conducted in a randomized block design, using a 3×5 factorial arrangement, with three vinasse rates (0, 150 and 300 m3 ha-1) and five phosphogypsum rates (0, 3, 6, 9 and 12 Mg ha-1). The alfalfa chemical composition and shoot dry matter (SDW) and soil chemical properties (in the layers 0.0-0.2 and 0.21-0.4 m) were evaluated. The vinasse rates increased the soil potassium contents, while the phosphogypsum rates promoted linear increases in soil calcium and sulfur contents. The base saturation was increased and the magnesium content showed a quadratic response on the layer 0.21-0.4 m with the increase in phosphogypsum rates. The calcium, magnesium and phosphorus contents in the alfalfa leaves were lower with vinasse application. The phosphogypsum rates promoted linear increases in alfalfa SDW. Vinasse rated 150 m3 ha-1 was been enough to SDW increase. Calcium and magnesium contents in the leaves fitted a quadratic model, with maximum calcium content in the phosphogypsum rate of 9.5 Mg ha-1 and the minimum magnesium content in the phosphogypsum rate of 8.7 Mg ha-1. The leaf sulfur contents in all vinasse rates and leaf potassium contents in the highest vinasse rate showed maximum accumulation at near 9 Mg ha-1 of phosphogypsum.

The objective of this work was to evaluate the effects of the application of phosphogypsum and vinasse on soil chemical properties and productivity and nutritional characteristics of alfalfa (Medicago sativa). The experiment was conducted in a randomized block design, using a 3×5 factorial arrangement, with three vinasse rates (0, 150 and 300 m3 ha-1) and five phosphogypsum rates (0, 3, 6, 9 and 12 Mg ha-1). The alfalfa chemical composition and shoot dry matter (SDW) and soil chemical properties (in the layers 0.0-0.2 and 0.21-0.4 m) were evaluated. The vinasse rates increased the soil potassium contents, while the phosphogypsum rates promoted linear increases in soil calcium and sulfur contents. The base saturation was increased and the magnesium content showed a quadratic response on the layer 0.21-0.4 m with the increase in phosphogypsum rates. The calcium, magnesium and phosphorus contents in the alfalfa leaves were lower with vinasse application. The phosphogypsum rates promoted linear increases in alfalfa SDW. Vinasse rated 150 m3 ha-1 was been enough to SDW increase. Calcium and magnesium contents in the leaves fitted a quadratic model, with maximum calcium content in the phosphogypsum rate of 9.5 Mg ha-1 and the minimum magnesium content in the phosphogypsum rate of 8.7 Mg ha-1. The leaf sulfur contents in all vinasse rates and leaf potassium contents in the highest vinasse rate showed maximum accumulation at near 9 Mg ha-1 of phosphogypsum.

RESUMO O objetivo deste trabalho foi avaliar a capacidade antioxidante e a qualidade fisicoquímica e microbiológica de tomates cereja orgânicos cultivados com diferentes teores de nitrogênio (%N) utilizando águas residuárias da bovinocultura. As amostras de tomate foram obtidas na Fazendinha Agroecológica (SIPA - Seropédica, RJ) e submetidas a quatro diferentes tratamentos de acordo com os níveis de nitrogênio (T1=0, T2=50, T3=100 e T4=150 %N). Foram determinadas a umidade, teores de cinzas, lipídeos, proteínas e fibras totais. Além do pH, sólidos solúveis (ºBrix), açúcares totais e redutores (%); e acidez titulável (mg de NaOH por 100 g). O teor de compostos fenólicos e a capacidade antioxidante das amostras (DPPH e FRAP) foram avaliadas. Os diferentes %N afetaram o pH e o conteúdo de proteínas e sólidos solúveis totais dos tomates. Elevados teores de nitrogênio forneceram amostras com maiores capacidades antioxidantes (método DPPH) e compostos fenólicos. Em contrapartida, obtiveram-se as menores capacidades antioxidantes segundo o método FRAP nas amostras fertirrigadas com altos teores de nitrogênio. A fertirrigação não influenciou significativamente a qualidade microbiológica das amostras estudadas, que apresentaram contagem de coliformes fecaist <3 NMP/g e ausência de Salmonella em 25 g. | ABSTRACT The objective of this work was to evaluate the physicochemical and microbiological characteristics, antioxidant capacity and phenolic compounds of organic cherry tomatoes grown under fertigation with organic dairy cattle wastewater (DCW) with different nitrogen rates. Tomato plants, grown in an agroecological farm in Seropédica, State of Rio de Janeiro, Brazil, were subjected to four different nitrogen rates (T1=0, T2=50, T3=100 and T4=150% of N). The moisture, lipids, ashes, protein and total fiber contents, soluble solids (ºBrix), reducing and total sugars (%), pH and total titratable acidity (mg NaOH per 100 g) were evaluated. The total phenolic content (TPC) and the antioxidant capacity was determined by the DPPH and FRAP methods. The different nitrogen rates (%N) affected the pH, protein and soluble solids contents. The increase in %N increased the antioxidant capacities, according to the DPPH assay, and TPC. On the other hand, the tomatoes under fertigation with the highest %N presented lower antioxidant capacities according to the FRAP assay. The fertigation did not affect the microbiological characteristics of the tomatoes, which presented fecal coliforms count <3 NMP g-1 and absence of Salmonella in 25 g.

The objective of this work was to evaluate the physicochemical and microbiological characteristics, antioxidant capacity and phenolic compounds of organic cherry tomatoes grown under fertigation with organic dairy cattle wastewater (DCW) with different nitrogen rates. Tomato plants, grown in an agroecological farm in Seropédica, State of Rio de Janeiro, Brazil, were subjected to four different nitrogen rates (T1=0, T2=50, T3=100 and T4=150% of N). The moisture, lipids, ashes, protein and total fiber contents, soluble solids (ºBrix), reducing and total sugars (%), pH and total titratable acidity (mg NaOH per 100 g) were evaluated. The total phenolic content (TPC) and the antioxidant capacity was determined by the DPPH and FRAP methods. The different nitrogen rates (%N) affected the pH, protein and soluble solids contents. The increase in %N increased the antioxidant capacities, according to the DPPH assay, and TPC. On the other hand, the tomatoes under fertigation with the highest %N presented lower antioxidant capacities according to the FRAP assay. The fertigation did not affect the microbiological characteristics of the tomatoes, which presented fecal coliforms count <3 NMP g-1 and absence of Salmonella in 25 g.

RESUMO A cajazeira é encontrada em quase todas as Regiões do Brasil vem apresentando crescente demanda de frutos in natura e produtos processados. Este trabalho teve como objetivo avaliar o comportamento pós-colheita de frutos de cajá recobertos com fécula de mandioca e filme PVC. Para realização deste trabalho utilizaram-se frutos da cajazeira do genótipo ‘Lagoa Redonda’ colhidos em Limoeiro do Norte-CE em maturação fisiológica. Em seguida, os frutos foram transportados ao Laboratório de Química do IFCE Campus Limoeiro do Norte e armazenados por 8 dias a 29,7 ºC e 59% de UR. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 3 x 5, com três tipos de revestimento (controle, fécula de mandioca a 3 % e fécula de mandioca a 3 % associada ao filme de PVC) e cinco tempos de armazenamento (0,2, 4, 6 e 8 dias), com quatro repetições de cinco frutos por parcela. Avaliou-se a coloração da casca, aparência externa, teores de sólidos solúveis e de acidez titulável, relação SS/AT e a perda de massa. O uso do filme plástico foi eficiente na conservação da aparência externa e controle da perda de massa. O uso da fécula de mandioca não se mostrou tão eficiente quanto o filme plástico na conservação de cajás. A vida útil pós -colheita dos frutos foi de 8 dias para os tratados com fécula de mandioca ou fécula de mandioca associada ao PVC e de 6 dias para o controle. | ABSTRACT The mombin tree (Spondias mombin L.) is found in almost all regions of Brazil. Fresh and processed mombin fruits are increasingly demanded by the market. The objective of this work was to evaluate the post-harvest characteristics of mombin fruits coated with cassava starch and PVC film. Fruits from the mombin cultivar Lagoa-Redonda were harvested at physiological maturity in Limoeiro do Norte, State of Ceará, transported to the Chemistry Laboratory of the Ceará Federal Institute, Limoeiro do Norte campus, and stored for 8 days at 29.7°C and 59% of relative humidity. A completely randomized experimental design in a 3x5 factorial arrangement was used, with three coating types (control, cassava starch at 3%, and cassava starch at 3% combined with PVC film) and five storage times (0, 2, 4, 6 and 8 days), four replicates and five fruits per plot. The fruit skin color, external appearance, soluble solids (SS), titratable acidity (TA), SS/TA ratio and weight loss were evaluated. The PVC film was effective in maintaining the fruit external appearance and decreasing weight loss. The use of cassava starch was not as efficient as the PVC film for conserving mombin fruits. The post-harvest life of fruits was 8 days for those treated with cassava starch or cassava starch combined with PVC film, and 6 days for the control.

The mombin tree (Spondias mombin L.) is found in almost all regions of Brazil. Fresh and processed mombin fruits are increasingly demanded by the market. The objective of this work was to evaluate the post-harvest characteristics of mombin fruits coated with cassava starch and PVC film. Fruits from the mombin cultivar Lagoa-Redonda were harvested at physiological maturity in Limoeiro do Norte, State of Ceará, transported to the Chemistry Laboratory of the Ceará Federal Institute, Limoeiro do Norte campus, and stored for 8 days at 29.7°C and 59% of relative humidity. A completely randomized experimental design in a 3x5 factorial arrangement was used, with three coating types (control, cassava starch at 3%, and cassava starch at 3% combined with PVC film) and five storage times (0, 2, 4, 6 and 8 days), four replicates and five fruits per plot. The fruit skin color, external appearance, soluble solids (SS), titratable acidity (TA), SS/TA ratio and weight loss were evaluated. The PVC film was effective in maintaining the fruit external appearance and decreasing weight loss. The use of cassava starch was not as efficient as the PVC film for conserving mombin fruits. The post-harvest life of fruits was 8 days for those treated with cassava starch or cassava starch combined with PVC film, and 6 days for the control.