Physiology and production of sugar-apple under water stress and application of proline.

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.

Salicylic acid does not mitigate salt stress on the morphophysiology and production of hydroponic melon.

The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.

Physiology and production of sugar-apple under water stress and application of proline / Fisiologia e produção de pinheira sob estresse hídrico e aplicação de prolina

The objective of this study was to evaluate the physiology and production of sugar-apple as a function of irrigation intervals and foliar application of proline under the conditions of Paraíba's semi-arid region. A randomized block design was laid out in a 4 × 2 factorial scheme, with treatments resulting from the combination of four irrigation intervals (1, 4, 8 and 12 days) and two concentrations of proline (0 and 10 mM), with four replicates, and the plot consisted of four usable plants. Increase in irrigation intervals reduced the gas exchange of sugar-apple plants at 298 days after transplanting. Exogenous application of proline at concentration of 10 mM increased contents of chlorophyll a, chlorophyll b, total chlorophyll and carotenoids and fruit fresh mass in plants grown under 12-day irrigation intervals.

Objetivou-se com este trabalho avaliar a fisiologia e a produção da pinheira em função dos turnos de rega e aplicação foliar de prolina em condições do semiárido Paraibano. Foi utilizado o delineamento de blocos casualizados em esquema fatorial 4 × 2, cujos tratamentos resultam da combinação de quatro turno de rega (1, 4, 8 e 12 dias) e duas concentrações de prolina (0 e 10 mM), com quatro repetições, cuja a parcela foi constituída de quatro plantas úteis. O incremento nos turnos de rega reduziu as trocas gasosas das plantas de pinheira, aos 298 dias após o transplantio. A aplicação de prolina na concentração de 10 mM aumentou o extravasamento de eletrólitos no limbo foliar, a condutância estomática e diminuiu a concentração interna de CO2 das plantas de pinheira. A aplicação exógena de prolina na concentração de 10 mM aumentou os teores de clorofila a, b, total e carotenoides e a massa fresca de frutos nas plantas cultivadas sob turno de rega de 12 dias.

Salicylic acid does not mitigate salt stress on the morphophysiology and production of hydroponic melon / Ácido salicílico não mitiga o estresse salino sobre a morfofisiologia e produção de meloeiro hidropônico

The excess of salts present in the water can limit the hydroponic cultivation of melon in semi-arid regions of the Brazilian Northeast, making it necessary to use strategies that allow the use of these waters. Among these strategies, the use of elicitor substances stands out, such as salicylic acid. In this context, this study aimed to evaluate the effect of foliar application of salicylic acid in mitigating the harmful effects of salt stress on the morphophysiology and production of 'Gaúcho' melon cultivated in a hydroponic system. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution - ECsn (2.1, 3.2, 4.3, and 5.4 dS m-1) considered the plots and four salicylic acid concentrations - SA (0, 1.5, 3.0, and 4.5 mM), the subplots, with six replications. The foliar application of salicylic acid concentrations did not mitigate the deleterious effects of salt stress on the morphophysiology and yield of melon grown in hydroponic system. The concentration of 4.5 mM of salicylic acid intensified the harmful effects of the salinity of the nutrient solution on gas exchange and fresh weight of hydroponic melon.

O excesso de sais presentes na água pode limitar o cultivo hidropônico do meloeiro em regiões semiáridas do Nordeste brasileiro, fazendo-se necessária a utilização de estratégias que possibilitem o uso dessas águas, dentre essas estratégias, destaca-se a utilização de substâncias elicitoras, como ácido salicílico. Neste contexto, objetivou-se avaliar o efeito da aplicação foliar de concentrações de ácido salicílico na mitigação dos efeitos deletérios do estresse salino a morfofisiologia e produção do meloeiro 'Gaúcho' cultivado em sistema hidropônico. O experimento foi desenvolvido em casa de vegetação na Universidade Federal de Campina Grande, Pombal-PB. Adotou-se o delineamento inteiramente casualizado em esquema de parcelas subdivididas, sendo quatro níveis de condutividade elétrica da solução nutritiva - CEsn (2,1; 3,2; 4,3 e 5,4 dS m-1) considerados as parcelas e quatro concentrações de ácido salicílico - AS (0, 1,5; 3,0 e 4,5 mM), as subparcelas, com seis repetições. A aplicação foliar das concentrações de ácido salicílico não mitigaram os efeitos deletérios do estresse salino sobre a morfofisiologia e produção do meloeiro cultivado em sistema hidropônico. A concentração de 4,5 mM de ácido salicílico intensificou os efeitos deletérios da salinidade da solução nutritiva sobre as trocas gasosas e peso fresco de fruto do meloeiro hidropônico.