Photosynthesis and production of West Indian cherry irrigated with saline waters under nitrogen/potassium fertilization

Fertilization management is a technique that has been studied for the mitigation of salt stress in plants. In this perspective, this work aimed to evaluate the effects of combinations of potassium and nitrogen fertilization on the photosynthetic pigments, photosynthetic efficiency, and production of the West Indian cherry irrigated with waters of different salinities, between 420 and 550 days after transplanting. The experiment was conducted in an open field at the Center of Sciences and Agrifood Technology of the Federal University of Campina Grande, using 60 L lysimeters, in a randomized block design with a 5 x 4 factorial scheme, corresponding to five salinity levels of the irrigation water – ECw (0.3; 1.3; 2.3; 3.3, and 4.3 dS m-1) and four combinations of nitrogen and potassium fertilization (C1 = 70% N + 50% K2O; C2 = 100% N + 75% K2O; C3 = 130% N + 100% K2O, and C4 = 160% N + 125% K2O) of the dose recommended for the West Indian cherry, with three replications and one plant per plot. The cv. Flor Branca was studied through its grafting on a rootstock of the cv. Junco. The irrigation with ECw above 0.3 dS m-1 reduced the contents of chlorophyll a and b in the leaves, the photochemical efficiency, CO2 assimilation rate, instantaneous carboxylation efficiency, instantaneous water-use efficiency, and the number of fruits per plant. The combined fertilization with 70% of N + 50% of K2O increased the photosynthetic pigments, photosynthesis, and the number of fruits per plant, as well as mitigated the deleterious effects of water salinity on the production per plant up to the ECw of 2.3 dS m-1, which revealed to be the most adequate combination for West Indian cherry fertilization.Fertilization management is a technique that has been studied for the mitigation of salt stress in plants. In this perspective, this work aimed to evaluate the effects of combinations of potassium and nitrogen fertilization on the photosynthetic pigments, photosynthetic efficiency, and production of the West Indian cherry irrigated with waters of different salinities, between 420 and 550 days after transplanting. The experiment was conducted in an open field at the Center of Sciences and Agrifood Technology of the Federal University of Campina Grande, using 60 L lysimeters, in a randomized block design with a 5 x 4 factorial scheme, corresponding to five salinity levels of the irrigation water – ECw (0.3; 1.3; 2.3; 3.3, and 4.3 dS m-1) and four combinations of nitrogen and potassium fertilization (C1 = 70% N + 50% K2O; C2 = 100% N + 75% K2O; C3 = 130% N + 100% K2O, and C4 = 160% N + 125% K2O) of the dose recommended for the West Indian cherry, with three replications and one plant per plot. The cv. Flor Branca was studied through its grafting on a rootstock of the cv. Junco. The irrigation with ECw above 0.3 dS m-1 reduced the contents of chlorophyll a and b in the leaves, the photochemical efficiency, CO2 assimilation rate, instantaneous carboxylation efficiency, instantaneous water-use efficiency, and the number of fruits per plant. The combined fertilization with 70% of N + 50% of K2O increased the photosynthetic pigments, photosynthesis, and the number of fruits per plant, as well as mitigated the deleterious effects of water salinity on the production per plant up to the ECw of 2.3 dS m-1, which revealed to be the most adequate combination for West Indian cherry fertilization

Summer squash morphophysiology under salt stress and exogenous application of H2O2 in hydroponic cultivation

Summer squash is a vegetable of significant acceptance in the market due to its economic and nutritionalimportance, with the potential for expansion in the food industry. In this context, this study aimed to evaluate the gas exchange and growth of summer squash plants subjected to a saline nutrient solution and exogenous application of hydrogen peroxide. The study was conducted in a greenhouse in Pombal – PB. The cultivation system used was the Nutrient Film Technique (NFT) hydroponic system. The experimental design was completely randomized, in a 4 x 4 factorial arrangement, whose treatments consisted of four levels of electrical conductivityof the nutrient solution - ECns (2.1, 3.1, 4.1, and 5.1 dS m-1) and four concentrations of  hydrogen peroxide – H2O2 (0, 20, 40, and 60 μM), with three replications. The increase in the nutrient solution salinity from 2.1 dS m-1 reduced the leaf area and transpiration of the summer squash plants. Hydrogen peroxide at a concentration of 40 μM increased the root length, the instantaneous carboxylation efficiency, and the CO2 assimilation rate when the plants were subjected to the saline solution of 2.1 dS m-1. Also, the application of 60 μM H2O2 mitigated the effect of salt stress on the internal CO2 concentration and stomatal conductance of the summer squash plants.A abobrinha italiana é uma hortaliça de grande aceitação no mercado, por apresentar importância econômica e nutricional, com potencial para expansão na indústria alimentar. Nesse contexto, objetiva-se nessa pesquisa avaliar como trocas gasosas e o crescimento da abobrinha italiana submetida a solução nutritiva salina e aplicação exógena de peróxido de hidrogênio. O trabalho foi conduzido em casa de vegetação, em Pombal - PB. O sistema de cultivo utilizado foi o hidropônico tipo Técnica de Fluxo Laminar de Nutriente - NFT. O delineamento experimental foi casualizado, sem esquema fatorial 4 x 4, utilizado consistindo de quatro níveis salinos de solução nutritiva - CEsn (2,1; 3,1; 4,1 e 5,1 dS m 2 S 2 -1 ), e de peróxido de hidrogênio - H (0; 20; 40 e 60 μM), com 3 repetições. O aumento da salinidade da solução nutritiva a partir de 2,1 dS m -1 reduz a área foliar e a respiração das plantas de abobrinha. O peróxido de hidrogênio com concentração de 40 μM de incremento ou comprimento de raiz, uma eficiência instantânea de carboxilação e os índices de assimilação de CO 2 quando submetido a uma solução salina de 2,1 dS m -1 , como também uma aplicação de 60 μM possui o efeito de estresse salino sobre a concentração interna de CO 2 e a condutância estomática das plantas

Growth and physiology of Annona squamosa L. under different irrigation depths and phosphate fertilization

This study aimed to evaluate the growth and physiology of Annona squamosa seedlings under increasing irrigation depths and phosphorus doses. The experiment was conducted in protected environment, evaluating five irrigation depths and four P2O5- doses, arranged in 5 x 4 factorial scheme, in randomized blocks, with four replicates and one plant per plot. Treatments were irrigation depths of 60, 80, 100, 120 and 140% of the real evapotranspiration of the seedlings – ETr and phosphorus doses of 0, 350, 700 and 1050 mg dm-3 of P2O5-. Plants were evaluated at 120 days after transplanting with respect to growth, gas exchanges, leaf water potential and total dry matter accumulation. Phosphorus dose of 350 mg dm-3 promotes satisfactory dry matter accumulation for A. squamosa seedlings, especially under 100% ETr irrigation. Leaf water potential and gas exchanges of A. squamosa are affected by water stress, through both lack and excess of water. Stomatal conductance is the variable most sensitive to the lack of water, whereas photosynthesis and water use efficiency are the most sensitive to the excess of water. Irrigation depth of 100% ETr is ideal to produce A. squamosa seedlings, but the irrigation depth of 80% ETr can be used to produce these seedlings, disregarding small losses of growth

Ecophysiology of west indian cherry irrigated with saline water under phosphorus and nitrogen doses

The quantitative and qualitative scarcity of water resources is a frequent problem in the semi-arid region of the Brazilian Northeast. The availability of water for irrigation with high salts contents is common, affecting the growth and development of the crops. Thus, it is necessary to adopt strategies that allow the establishment of irrigated cultivation in this region. The objective of this work was to evaluate the effect of water salinity and phosphorus/nitrogen combinations on the ecophysiology of the West Indian cherry grafted in the first year of cultivation. The research was carried out in a protected environment, in lysimeters filled with a Regolithic Neosol of loamy clay texture, having low initial phosphorus content. The experiment was arranged in a randomized block design, arranged in a 5x4 factorial scheme, with five levels of electrical conductivity of the irrigation water - CEa (0.6, 1.4, 2.2, 3.0 and 3.8 dS m -1) and four manures of fertilization with phosphorus and nitrogen (100: 100, 140: 100, 100: 140 and 140: 140% of the recommendation of P/N), with three replications, each plot consisting of one plant. Increased salinity of irrigation water reduced growth, photosynthesis and the production of West Indian cherry. Fertilization with 140% of the phosphorus and nitrogen recommendation minimizes the deleterious effect of salinity on West Indian cherry irrigated with water up to 3.0 dS m-1

Morfofisiologia e componentes de produção de mini-melancia sob níveis de reposição hídrica e adubação nitrogenada

No semiárido do Nordeste do Brasil, a irregularidade de chuvas e elevada evapotranspiração proporcionam déficit hídrico nas plantas na maior parte dos meses do ano, destacando-se como fator limitante para produção de olerícolas. Assim, a identificação de estratégias capazes de amenizar os efeitos do déficit hídrico nas plantas é essencial para produção sob condições irrigadas. Nesse contexto, objetivou-se avaliar o efeito da adubação nitrogenada na morfofisiologia e nos componentes de produção de mini-melancia 'Sugar Baby'. O experimento foi conduzido na Fazenda Experimental ‘Rolando Rivas Castellón’, São Domingos, Paraíba, sob condições de casa de vegetação, utilizando-se o delineamento de blocos casualizados em esquema fatorial 4 × 4, correspondendo a quatro níveis de reposição hídrica (50, 75, 100 - controle e 125% da evapotranspiração real da cultura - ETr) e quatro doses de nitrogênio - DN (50, 75, 100 e 125% da dose recomendada), com 3 repetições, totalizando 48 plantas. Foram avaliadas as variáveis de trocas gasosas, os teores de pigmentos fotossintéticos, o conteúdo relativo de água e o extravasamento de eletrólitos, o crescimento e a produção de fitomassa, os componentes de produção e a qualidade pós-colheita dos frutos de mini-melancia. A irrigação deficitária com 50% da evapotranspiração real inibiu as trocas gasosas, a síntese de pigmentos fotossintéticos, o crescimento, e a qualidade dos frutos da mini-melancieira ‘Sugar Baby’, independente da dose de nitrogênio. A lâmina de água com 125% da evapotranspiração real combinada à adubação de 100% da recomendação de nitrogênio proporcionou maiores teores de clorofilas totais, número de folhas e de fitomassa seca das raízes, caule, total, parte aérea e pH dos frutos de mini-melancieira ‘Sugar Baby’

Growth and fluorescence of ‘Tahiti’ acid lime/rootstock on Sunki mandarin hybrids under salinity

The objective of this study was to evaluate the ecophysiological behavior of ‘Tahiti’ acid lime/rootstock grafted on Sunki mandarin hybrids during the prefloration stage of the plants, in the field, under saline stress. The progenies originating from crossings of the ‘Sunki’ mandarin with ‘Rangpur’ lime and Poncirus trioliata, as rootstocks, combined with the ‘Tahiti’ acid lime as a scion. The experiment was carried out under field conditions, at the Federal University of Campina Grande (UFCG), Pombal PB fields. In drainage lysimeter of 150 dm3, studying 10 scion/rootstock combinations, irrigated with two water salinity levels (CEa) (S1 = 0.3 and S2 = 3.0 dS m-1) making a 10 x 2 factorial scheme. The experimental design was a randomized block design, with 3 replicates and each plot consisting of a useful plant, totalizing 60 parcels. The scion/rootstock plants were transplanted at one year of age from the rootstocks sowing, being the beginning of the applications of the saline stress to the 15 days after the transplant lasting until the period of flowering, that is, up to 195 days after transplanting, During this period the plants were analyzed for growth and chlorophyll fluorescence a. The combinations less sensitive to salinity were composed of the ‘Tahiti’ grafted with TSKFL x (LCR x TR) - 018, TSKFL x TRBK - 011 and TSKFL x TRBK - 030, it being possible to use saline water with up to 3.0 dS m-1 in irrigation. Salinity did not damage the biochemical phase of the scion/rootstock combinations, only affecting the initial fluorescence of the lighted tissue

Ecophysiology of citrus canopy / rootstock combinations under water salinity until pre-flowering.

As plantas cítricas possuem grande importância socioeconômica no Brasil e no mundo, todavia, em regiões com limitações hídricas qualitativas e quantitativas, a exemplo em localidade do semiárida, há necessidade de estratégias de manejo que melhorem o desempenho da cultura. Com isso, objetivou-se avaliar a ecofisiologia de genótipos de citros a partir de progênies oriundas de cruzamento da tangerineira ‘Sunki’ com limão ‘Cravo’ e Poncirus trioliata, estando combinadas à lima ácida ‘Tahiti’ como copa, todos obtidos junto a Embrapa Mandioca e Fruticultura, em Cruz das Almas, BA. O experimento foi realizado em condições de campo, na Universidade Federal de Campina Grande (UFCG), campos Pombal PB, em lisímetro de drenagem com capacidade de 150 dm3, estudando-se 10 combinações copa/porta-enxerto, referentes a Tahiti enxertada em 10 genótipos de citros (nove híbridos e uma testemunha), irrigadas com dois níveis de salinidade da água (CEa) (S1=0,3 e S2=3,0 dS m-1), perfazendo um esquema fatorial 10 x 2. Utilizou-se o delineamento experimental de blocos casualizados, com 3 repetições e cada parcela constituída por uma planta útil, totalizando 60 parcelas. As mudas enxertadas foram transplantadas com um ano de idade desde o semeio, sendo o início das aplicações do estresse salino aos 15 dias após o transplante perdurando até o período de prefloração, ou seja, até os 195 dias após o transplantio. Durante esse período as plantas foram analisadas quanto ao crescimento, trocas gasosas, fluorescência da clorofila a. A irrigação com água salina de 3,0 dS m-1 não influenciou atividade fotossintética das combinações copa/porta-enxerto de citros estudadas até a prefloração. Os maiores crescimentos foram obtidos pelas combinações entre a lima ácida ‘Tahiti’ com o TSKC x (LCR x TR) – 017, TSKFL x TRBK – 011 e o TSKFL x TRBK – 030, mesmo sob maior nível de salinidade; As maiores reduções no crescimento em função da salinidade são observadas nas combinações compostas pelo ‘Tahiti’ enxertado com TSKC x (LCR x TR) – 032, TSKFL x TRBK – 028 e a testemunha LCRSTC, sendo esta última a mais sensível a salinidade; As combinações menos sensíveis à salinidade foram compostas pelo ‘Tahiti’ enxertado com o TSKFL x (LCR x TR) – 018, TSKFL x TRBK – 011, TSKFL x TRBK – 30.Citrus plants have great socioeconomic importance in Brazil and in the world, however, In regions with qualitative and quantitative water limitations, the example, in location of semiariárido, There need for management strategies that improve crop performance. With that, the objective of this study was to evaluate the ecophysiology of citrus genotypes of progenies of crossing gives mandarina Sunki 'with lemon' blackhead 'and Poncirus trioliata, Being combined with the acidic file 'Tahiti' as a scullery Being combined with the acidic file 'Tahiti how scullery, All obtained Together The, In Cross of Almas, BA. The experiment was carried out under field conditions, At the Federal University of Campina Grande (UFCG), Pombal PB fields, Em lisímetro de drenagem com capacidade de 150 dm3, Studying 10 scullery/rootstock combinations, Referring to Tahiti grafted on 10 citrus genotypes (nine hybrids and one witness) Irrigated with two water salinity levels (CEa) (S1 = 0.3 and S2 = 3.0 dS m-1) Making a 10 x 2 factorial scheme The experimental design was a randomized block design, With 3 replicates and each plot consisting of a useful plant, totalizing 60 Parcel. The grafted seedlings were transplanted at one year of age from the sowing, Being the beginning of the applications of the saline stress to the 15 days after the transplant lasting until the period of prefloração, That is, up to 195 days after transplanting, During this period the plants were analyzed for growth, Gaseous Exchanges, Chlorophyll fluorescence a. Irrigation with 3.0 dS m-1 saline water did not influence photosynthetic activity of the citrus canopy / rootstock combinations studied until pre-chlorination; The highest growths were obtained by the combinations in between The Tahiti acid file with TSKC x (LCR x TR) - 017, TSKFL x TRBK - 011 and TSKFL x TRBK - 030, even under a higher salinity level; The highest reductions in growth as a function of salinity are observed in the combinations composed of Tahiti grafted TSKC x (LCR x TR) - 032, TSKFL x TRBK - 028 and the LCRSTC control, the latter being the most sensitive to salinity; The combinations less sensitive to salinity were composed of Tahiti 'grafted with TSKFL x (LCR x TR) - 018, TSKFL x TRBK - 011, TSKFL x TRBK – 30

Interação salinidade da água de irrigação e substratos na produção de mudas de maracujazeiro amarelo

The aim of the present study was to evaluate the yield og yellow passion fruit seedling according to the interaction between substrate composition and salinity levels of irrigation water in an experiment carried out from November, 2013 to January 2014, in a protected environment (greenhouse) at the Center of Science and Agrifood Technology - CCTA, Federal University of Campina Grande - UFCG, located in the municipality of Pombal, PB, Brazil. A randomized complete block design in a 4x3 factorial consisted of four levels of irrigation water salinity ECw (0.3, 1.5, 2.5 and 3.5 dS m-1) and three different substrates [S = soil; EO = Soil + sheep manure (2:1); and SC = soil + commercial substrate (2:1)], with a total of 12 treatments with three replications and three useful plants per replication were used. The increase in salinity of irrigation water reduced the emergence, growth and dry matter accumulation of passion fruit seedlings, being the total dry matter the variable that was most affected by salinity. The substrate containing soil + sheep manure in the ratio of 2:1 promoted the highest initial growth and dry matter accumulation of yellow passion fruit seedlings, using a maximun level of 1.5 dS m-1 of saline irrigation were used.Objetivou-se avaliar a produção de mudas de maracujazeiro amarelo em resposta a interação entre a composição de substratos e níveis de salinidade da água de irrigação em experimento desenvolvido no período de novembro de 2013 a janeiro de 2014, em ambiente protegido (casa de vegetação) do Centro de Ciências e Tecnologia Agroalimentar – CCTA, da Universidade Federal de Campina Grande - UFCG, localizado no município de Pombal, Paraíba PB. Adotando-se o delineamento experimental de blocos casualizados, em esquema fatorial4x3 constituído de quatro níveis de salinidade da água de irrigação - CEa (0,3; 1,5; 2,5 e 3,5 dS m-1) e três substratos [S= solo;S+EO= solo + esterco ovino (2:1);e S+SC= solo + substrato comercial (2:1)], totalizando 12 tratamentos, com três repetições e três plantas uteis por repetição. O aumento da salinidade da água de irrigação reduziu a emergência, o crescimento e o acúmulo de matéria seca das mudas de maracujazeiro amarelo, sendo a matéria seca total a variável mais afetada pela salinidade. O substrato contendosolo + esterco ovino na proporção (2:1) promoveu o maior crescimento inicial e acúmulo de matéria seca as mudas de maracujazeiro amarelo quando irrigadas com salinidade até o nível de 1,5 dS m-1

Interação salinidade da água de irrigação e substratos na produção de mudas de maracujazeiro amarelo

The aim of the present study was to evaluate the yield og yellow passion fruit seedling according to the interaction between substrate composition and salinity levels of irrigation water in an experiment carried out from November, 2013 to January 2014, in a protected environment (greenhouse) at the Center of Science and Agrifood Technology - CCTA, Federal University of Campina Grande - UFCG, located in the municipality of Pombal, PB, Brazil. A randomized complete block design in a 4x3 factorial consisted of four levels of irrigation water salinity ECw (0.3, 1.5, 2.5 and 3.5 dS m-1) and three different substrates [S = soil; EO = Soil + sheep manure (2:1); and SC = soil + commercial substrate (2:1)], with a total of 12 treatments with three replications and three useful plants per replication were used. The increase in salinity of irrigation water reduced the emergence, growth and dry matter accumulation of passion fruit seedlings, being the total dry matter the variable that was most affected by salinity. The substrate containing soil + sheep manure in the ratio of 2:1 promoted the highest initial growth and dry matter accumulation of yellow passion fruit seedlings, using a maximun level of 1.5 dS m-1 of saline irrigation were used.Objetivou-se avaliar a produção de mudas de maracujazeiro amarelo em resposta a interação entre a composição de substratos e níveis de salinidade da água de irrigação em experimento desenvolvido no período de novembro de 2013 a janeiro de 2014, em ambiente protegido (casa de vegetação) do Centro de Ciências e Tecnologia Agroalimentar – CCTA, da Universidade Federal de Campina Grande - UFCG, localizado no município de Pombal, Paraíba PB. Adotando-se o delineamento experimental de blocos casualizados, em esquema fatorial4x3 constituído de quatro níveis de salinidade da água de irrigação - CEa (0,3; 1,5; 2,5 e 3,5 dS m-1) e três substratos [S= solo;S+EO= solo + esterco ovino (2:1);e S+SC= solo + substrato comercial (2:1)], totalizando 12 tratamentos, com três repetições e três plantas uteis por repetição. O aumento da salinidade da água de irrigação reduziu a emergência, o crescimento e o acúmulo de matéria seca das mudas de maracujazeiro amarelo, sendo a matéria seca total a variável mais afetada pela salinidade. O substrato contendosolo + esterco ovino na proporção (2:1) promoveu o maior crescimento inicial e acúmulo de matéria seca as mudas de maracujazeiro amarelo quando irrigadas com salinidade até o nível de 1,5 dS m-1

GAS EXCHANGE AND CHLOROPHYLL FLUORESCENCE OF CITRUS ROOTSTOCK VARIETIES UNDER SALT STRESS

ABSTRACT High salt concentration in water are common in Brazilian semirad region, being important to research alternatives for use this waters on crop, like use of tolerant genotypes to salinity. Thus, in order to evaluate the saline stress perception of citrus rootstocks varieties crop from gas exchange and fluorescence analysis, an experiment was realized in greenhouse at the Center for Science and Technology Agrifood, CCTA, of Federal University of Campina Grande, UFCG, Pombal, PB, Brazil. It was studied in a randomized block design with factorial scheme (2x4), two salinity levels (0.3 and 4.0 dSm-1) and four varieties of citrus rootstocks [1 -common Sunki mandarin (TSKC), 2 - Florida Rough lemon (LRF), 3 -Santa Cruz Rangpur lime (LCRSTC) and 4-Volkamer lemon (LVK)], with three replications. The citrus rootstocks varieties grown on hydroponic system and at 90 days after sowing the plants were evaluated by gas exchange and PSII fluorescence at 0, 24 and 48 hours after application of treatments to determine the times for the physiological establishment of salt stress. The first 48h under saline conditions promoted changes in gas exchange and PSII fluorescence in varieties TSKC, LRF and LCRSTC indicating the begin of physiological stress; the common ‘Sunki’ mandarin and the ‘Florida Rough’ lemon are the more sensitive genotypes to saline stress, in order hand the ‘Santa Cruz Rangpur’ lime and ‘Volkamer’ lemon are the genotypes more tolerant