Water-Retaining Polymer and Planting Pit Size on Chlorophyll Index, Gas Exchange and Yield of Sour Passion Fruit with Deficit Irrigation.

Water availability is a limiting factor for the cultivation of sour passion fruit. Soil management techniques and the use of water-retaining polymers can increase soil water retention, reducing the frequency of irrigation in the crop. In this context, the objective of the research was to evaluate the gas exchange, the chlorophyll index, and the yield of the sour passion fruit cv. BRS GA1 as a function of irrigation depths, pit volumes, and doses of water-retaining polymer. The experiment was carried out in randomized blocks, in plots subdivided in a 2 × (2 × 5) arrangement, with irrigation depths of 70 and 100% of the crop evapotranspiration (ETc) as the main plot, the subplots with the volumes of pit of 64 and 128 dm3, and doses of the water-retaining polymer of 0, 0.5, 1.0, 1.5, and 2.0 g dm-3. The interaction of irrigation depths × pit volumes × doses of water-retaining polymer influences chlorophyll indexes, gas exchange, and water productivity, with positive impacts on yield of the sour passion fruit. The water depth of 70% of ETc increased the yield of sour passion fruit, in pits of 64 dm3. The application of doses of up to 1.1 g dm-3 of the water-retaining polymer and irrigation with water of 70% of ETc is recommended, and a dose of 2.0 g dm-3 of the water-retaining polymer in a pit volume of 128 dm3, associated with an irrigation depth of 100% ETc causes stress in sour passion fruit plants due to excess water.

Salinity and Mulching Effects on Nutrition and Production of Grafted Sour Passion Fruit.

The Brazilian semiarid region stands out in terms of sour passion fruit production. Local climatic conditions (high air temperature and low rainfall), combined with its soil properties (rich in soluble salts), increase salinity effects on plants. This study was carried out in the experimental area "Macaquinhos" in Remígio-Paraíba (Brazil). The aim of this research was to evaluate the effect of mulching on grafted sour passion fruit under irrigation with moderately saline water. The experiment was conducted in split-plots in a 2 × (2 × 2) factorial scheme to evaluate the effects of the combination of irrigation water salinity of 0.5 dS m-1 (control) and 4.5 dS m-1 (main plot), passion fruit propagated by seed and grafted onto Passiflora cincinnata, with and without mulching (subplots), with four replicates and three plants per plot. The foliar Na concentration in grafted plants was 90.9% less than that of plants propagated via seeds; however, it did not affect fruit production. Plastic mulching, by reducing the absorption of toxic salts and promoting greater absorption of nutrients, contributed to greater production of sour passion fruit. Under irrigation with moderately saline water, the plastic film in the soil and seed propagation promote higher production of sour passion fruit.

Impact of nitrogen and potassium nutrition on papaya (Pawpaw) fruit quality / Impacto da nutrição nitrogenada e potássica na qualidade de frutos de mamoeiro formosa

Pawpaw (Carica papaya L.), also known papaya, is a fruit species with economic and social importance for Brazil, the second main world producer. Although this characteristic the relationship between N and K nutrition and papaya fruit quality has been poorly studied. Thus, an objective with this study was to evaluate the effect of nitrogen and potassium for papaya (pawpaw) fruit quality produced in North eastern Brazil. The experimental design consisted of randomised blocks, with treatments distributed in a factorial arrangement (4 x 4), using four nitrogen doses (320, 400, 480 and 560 g of N plant-1) and four potassium doses (380, 475, 570 e 665 g of K2O plant-1), containing with four replications of three plants each. The fruit characteristics, such as fruit mass, titratable acidity, soluble solids, pulp pH and fruit length and width, were recorded. The fruit qualityof pawpaw depend on nitrogen and potassium leaf concentration. The higher fruit quality parameters regarding to soluble solids, pH, fruit length and fruit mass are associated to 45.30 g kg-1 leaf N concentration and 37.55 leaf K concentration.

O mamoeiro Formosa (Carica papaya L.) é uma espécie frutífera de importância social e econômica para o Brasil, o segundo maior produtor mundial. Apesar dessa característica, a relação entre a nutrição com N e K e a qualidade de frutos têm sido pouco estudada. Assim, objetivou-se com o presente trabalho avaliar o efeito da nutrição nitrogenada e potássica na qualidade de frutos do mamoeiro Formosa no Nordeste brasileiro. Adotou-se o delineamento em blocos casualizados, em esquema fatorial 4 x 4, correspondentes a doses de nitrogênio em cobertura (320, 400, 480 e 560 g planta-1) e doses de potássio em cobertura (380, 475, 570 e 665 g planta-1), contendo quatro repetições de três plantas por parcela cada. A qualidade dos frutos foi determinada, avaliando-se a massa de fruto, acidez titulável, sólidos solúveis, pH da polpa, diâmetro longitudinal e transversal dos frutos. A qualidade de frutos de mamão formosa depende da concentração foliar de nitrogênio e potássio. Os melhores resultados de sólidos solúveis, pH de polpa, diâmetro longitudinal de frutos estão associados às concentrações foliares de 45,30 g kg-1 de N e 37,55 g kg-1 de K.

Emergência de plântulas de fava em função de posições e profundidades de semeadura / Emergence of lima bean seedlings as a function of position and depth of sowing

A fava, Phaseolus lunatus L., é cultivada em quase todo o território nacional, devido à sua importância econômica. No Nordeste do Brasil, tornou-se uma alternativa de renda e alimento para a população, pois seus grãos são consumidos maduros ou verdes. A pesquisa foi realizada em casa-de-vegetação, no Setor de Horticultura do Campus Professora Cinobelina Elvas, da Universidade Federal do Piauí, situado no município de Bom Jesus, Piauí, com o objetivo de verificar o efeito da posição e da profundidade de semeadura na emergência e no vigor de sementes de P. lunatus L. O delineamento utilizado foi DIC, em esquema fatorial 3X5, com quatro repetições de 25 sementes, onde os tratamentos foram 3 posições das sementes (HC, HB E HL) e 5 profundidades (1, 2, 3, 4, e 5 cm). Avaliaram-se a porcentagem de emergência, primeira contagem de emergência, índice de velocidade de emergência, comprimento e massa seca das plântulas. As sementes de P. lunatus devem ser semeadas com o hilo voltado para cima (HC) na profundidade de 3,3 cm.

Phaseolus lunatus L., is cultivated in almost all the national territory, due to its economic importance. In Northeastern Brazil, it has become an alternative source of income and food for native people because its grains are eaten mature or not. The research work was conducted in a net-house at the Horticulture Sector of Campus "Profa. Cinobelina Elvas", Federal University of Piaui, in Bom Jesus county, Piaui State, Brazil aiming to verify the effect of seed position and depth of sowing on seedling emergence and vigor of P. lunatus L. seeds. The experimental design was completely randomized with four replications of 25 seeds each, and treatments were three seed positions of sowing (HB, HL and HC ) and five depths (1, 2, 3, 4 and 5 cm). The percentage of emergence, emergence first count, emergence speed index, length and dry mass of seedlings were recorded. The P. lunatus seeds should be sown with the hilum facing up (HC) at a depth of 3.3 cm.

Crescimento e produção do maracujazeiro amarelo, sob diferentes fontes e doses de fósforo em cobertura / Growth and production of yellow passion fruits plants under different sources and doses of phosphorus

O Brasil é o maior produtor mundial do maracujazeiro amarelo, uma cultura exigente em nutrientes, mas pouco estudada quanto à adubação fosfatada, fundamental no estabelecimento da cultura. Nesse sentido, um experimento foi desenvolvido no período de março de 2010 a abril de 2011, no município de Remígio, PB, objetivando avaliar os atributos vegetativo e produtivo do maracujazeiro amarelo cultivar IAC 273/277 + 275 sob adubação com diferentes fontes e doses de fósforo em cobertura. O ensaio foi instalado em blocos ao acaso, em três repetições e 12 plantas por parcela, num arranjo fatorial de 2 x 5, referente às fontes de superfosfato simples e triplo, nas doses de 0, 12, 18, 24 e 30 g de P2O5 cova-1. Foram avaliadas as seguintes variáveis: diâmetro do caule, número de ramos produtivos, número de frutos por planta, massa média de frutos, produção por planta e produtividade. As fontes e doses de fósforo influenciam o crescimento e produção do maracujazeiro amarelo. O superfosfato triplo é a fonte fosfatada mais eficiente para o crescimento e produção do maracujazeiro amarelo. A dose com a máxima produtividade de maracujazeiro amarelo é 42,86 g de superfosfato triplo.

Brazil is the largest world producer of yellow passion fruit, a fruit crop which is exigent in nutrients, although little studied in relation to phosphorus fertilizing, fundamental on plant establishment. An experiment was carried out during the period of March/2010 to April/2011 in Remígio County, Paraiba State, Brazil, in order to evaluate the vegetative and productive attributes of yellow passion fruit plants under different sources and doses of phosphorus. Treatments were distributed in randomized blocks in tree replications and twelve plants by plot using the factorial design 2 x 5 referring the sources of superphosphate triple and superphosphate simple at levels P2O5 of 0, 12, 18, 24 and 30 g cave-1. The following variables were recorded: stem diameter, number of productive branches, number of fruits per plant, fruit mass and fruit yield. The sources and doses of phosphorus affected growth and fruit production of yellow passion plants. The triple superphosphate is the most phosphorus efficient source for growth and fruit production of yellow passion fruit. The triple superphosphate dose which promoted the maximum yield of yellow passion fruit is 42.86 g.

Produtividade e qualidade de frutos do mamoeiro em função de tipos e doses de biofertilizantes / Yield and fruit quality of papaya as function of types and levels of biofertilizers

Os biofertilizantes são produtos orgânicos geralmente obtidos via anaerobiose, estudados, principalmente, como fitoprotetores para a agricultura, mas que podem também incrementar a produção das plantas. Nesse sentido, um experimento de campo foi desenvolvido, no período de maio/2003 a agosto/2004, no município de Remígio-Pb, para avaliar os efeitos de dois biofertilizantes bovinos sobre a massa média, produtividade e a qualidade externa e interna dos frutos do mamoeiro Havaí (Carica papaya L.) cultivar ‘Baixinho de Santa Amália’. Os tratamentos foram dispostos em blocos casualizados com três repetições e 15 plantas por parcela, em esquema fatorial 2 x 5, sendo dois biofertilizantes: puro (água e esterco fresco de bovino) e o supermagro (além de água e esterco bovino fresco é enriquecido com macro, micronutrientes e mistura protéica), aplicados ao solo na forma líquida nos volumes 0,0; 0,5; 1,0; 1,5; e 2,0 L cova-1. A massa média, a produtividade e as variáveis referentes à qualidade externa e interna dos frutos não deferiram entre os tipos de biofertilizantes, mas responderam significativamente às doses de ambos os insumos. Os resultados, exceto quanto à firmeza dos frutos, demonstram efeitos positivos dos biofertilizantes no cultivo do mamoeiro ‘Baixinho de Santa Amália’ em termos de rendimento por área e qualidade físico-química dos frutos.

Biofertilizers are organic products usually obtained from an anaerobic process, evaluated mainly asphytoprotectors for agriculture, although they can improve fruit production. By this way, a field experiment was carried out in Remígio County, Paraiba State, Brazil, to evaluate the effects of two bovine biofertilizerson yield, medium mass and quality of papaya fruits (Carica papaya L.), ‘Baixinho de Santa Amália’cultivar. Treatments were distributed in a randomized complete blocks design with three replications and 15 plants in each parcel, in a 2 x 5 factorial arrangement, with two biofertilizers: simple (water and fresh bovine manure) and supermagro (water, fresh bovine manure, macro and micronutrients and a proteinmix), applied in soil under liquid form at five volumes, as follows: 0.0; 0.5; 1.0; 1.5; e 2.0 L cave-1. There was no statistical difference between biofertilizers for fruit mass, yield and external and internal fruit quality variables, while between volumes differences were registered for both biofertilizers. The results,except for fruit firmness, registered positive effects of the biofertilizers on ‘Baixinho de Santa Amália’papaya cultivar in relation to yield and physical and chemical fruit quality.