Aplicação foliar de ácido ascórbico em plantas de rabanete e seu potencial na tolerância à deficiência hídrica
Carregando...
Data
2020-12-16
Autores
Santos, Osvaldir Feliciano dos
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O aumento da demanda de hortaliças no mundo, é recorrente aos elevados teores de nutrientes e minerais que tais plantas possuem. Neste aspecto o rabanete se destaca devido a suas diversas propriedades nutracêuticas, além de bons teores de vitaminas. Assim como outras hortaliças, possui grande suscetibilidade a deficiência hídrica (DH), o qual impacta negativamente sobre seu rendimento. A aplicação exógena de vitaminas pode tornar-se possível alternativa na atenuação deste estresse, em decorrência de sua ação indireta em diversos componentes da planta. O objetivo dos experimentos foi determinar efeitos fisiológicos, bioquímicos, biométricos e nutricionais da DH e a influência do ácido ascórbico (AsA) na mitigação desses efeitos em plantas de rabanete cultivadas em ambiente protegido. Os ensaios foram conduzidos em blocos casualizados em esquema de parcelas subdivididas, adotando-se duas tensões de água no solo (10 e 30 kPa) e, nas subparcelas, cinco doses de ácido ascórbico (0, 250, 500, 750 e 1000 ppm). Em outro experimento complementar, aplicou-se duas tensões de água no solo de (10 e 20 kPa) e nas subparcelas quatro períodos de aplicação de AsA na dosagem de 1000 ppm (controle, 3, 6 e 9 dias), com quatro repetições. Verificou-se que a DH alterou todos os padrões de parâmetros morfológicos, bioquímicos, fisiológicos e nutricionais das plantas. Independentemente do fator hídrico, houve maior incremento das variáveis quando as plantas foram tratadas com 1000 ppm de AsA. A maximização da eficácia desta dosagem em plantas submetidas ao DH foi registrada em frequências de aplicações a cada 9 dias. Pode-se concluir que a aplicação de AsA apresenta potencial para mitigar o impacto da DH em plantas de rabanete além de proporcionar maior rendimento da cultura, mesmo em ambientes com boa disponibilidade hídrica.
The increase in the demand for vegetables in the world is recurrent to the high levels of nutrients and minerals that such plants have. In this respect, the radish stands out due to its various nutraceutical properties, in addition to good levels of vitamins. Like other vegetables, it is highly susceptible to water deficiency (DH), which negatively impacts its yield. The exogenous application of vitamins may become a possible alternative to alleviate this stress, due to its indirect action on several components of the plant. The purpose of the experiments was to determine the physiological, biochemical, biometric and nutritional effects of DH and the influence of ascorbic acid (AsA) in mitigating these effects in radish plants grown in a protected environment. The tests were carried out in randomized blocks in a split plot scheme, adopting two water tensions in the soil (10 and 30 kPa) and, in the subplots, five doses of ascorbic acid (0, 250, 500, 750 and 1000 ppm). In another complementary experiment, two water tensions were applied to the soil of (10 and 20 kPa) and in the subplots four periods of application of AsA at 1000 ppm (control, 3, 6 and 9 days), with four repetitions. It was found that DH altered all patterns of morphological, biochemical, physiological and nutritional parameters of plants. Regardless of the water factor, there was a greater increase in variables when the plants were treated with 1000 ppm AsA. The maximization of the effectiveness of this dosage in plants submitted to DH was registered in frequency of applications every 9 days. It can be concluded that the application of AsA has the potential to mitigate the impact of DH on radish plants in addition to providing greater crop yield, even in environments with good water availability.
The increase in the demand for vegetables in the world is recurrent to the high levels of nutrients and minerals that such plants have. In this respect, the radish stands out due to its various nutraceutical properties, in addition to good levels of vitamins. Like other vegetables, it is highly susceptible to water deficiency (DH), which negatively impacts its yield. The exogenous application of vitamins may become a possible alternative to alleviate this stress, due to its indirect action on several components of the plant. The purpose of the experiments was to determine the physiological, biochemical, biometric and nutritional effects of DH and the influence of ascorbic acid (AsA) in mitigating these effects in radish plants grown in a protected environment. The tests were carried out in randomized blocks in a split plot scheme, adopting two water tensions in the soil (10 and 30 kPa) and, in the subplots, five doses of ascorbic acid (0, 250, 500, 750 and 1000 ppm). In another complementary experiment, two water tensions were applied to the soil of (10 and 20 kPa) and in the subplots four periods of application of AsA at 1000 ppm (control, 3, 6 and 9 days), with four repetitions. It was found that DH altered all patterns of morphological, biochemical, physiological and nutritional parameters of plants. Regardless of the water factor, there was a greater increase in variables when the plants were treated with 1000 ppm AsA. The maximization of the effectiveness of this dosage in plants submitted to DH was registered in frequency of applications every 9 days. It can be concluded that the application of AsA has the potential to mitigate the impact of DH on radish plants in addition to providing greater crop yield, even in environments with good water availability.
Descrição
Palavras-chave
Estresse hídrico, Vitamina C, Raphanus sativus, Produção vegetal, Water stress, Vitamin C, Plant production