Biofortificação agronômica com selênio em cultivares de repolho
Carregando...
Arquivos
Data
2018-04-13
Autores
Barboza, Eliza [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O objetivo deste trabalho foi avaliar concentrações de selênio (selenato e selenito de sódio) no crescimento, produção e biofortificação de duas cultivares de repolho. Para isso foram realizados dois experimentos em casa de vegetação, em sistema hidropônico, no período de julho a novembro de 2014, na UNESP, campus Jaboticabal-SP. Os experimentos diferiram conforme a fonte de selênio (Se) utilizada (selenato e selenito de sódio). Em ambos os experimentos, avaliaram-se dois fatores, sendo: duas cultivares de repolho (‘Fênix’ e 'Red Dinasty’) e cinco concentrações de Se (0, 5, 15, 30 e 60 µmol L-1) na solução nutritiva. O delineamento experimental utilizado foi o de blocos casualizados, com esquema fatorial 2 x 5 e quatro repetições. As variáveis analisadas foram o teor e acúmulo de Se na raiz e cabeça de repolho, área, diâmetro, comprimento e densidade de raiz, produtividade de repolho, massa seca de raiz, caule e cabeça de repolho e o teor e acúmulo de nitrogênio, fósforo e enxofre na cabeça de repolho. As fontes selenato e selenito promoveram o crescimento das raízes de repolho devido aos aumentos verificados em área, diâmetro, comprimento e densidade de raiz, em baixas concentrações de Se aplicadas. O aumento da produção de massa seca de raiz provavelmente foi devido o maior crescimento da raiz, que foi influenciado pelo fornecimento de Se. A massa seca do caule foi diferente apenas entre as cultivares de repolho com aplicação de selenato ou selenito. O teor de nitrogênio apresentou diferenças apenas entre as cultivares quando utilizada a fonte selenito. Ambas as fontes de Se também proporcionaram aumentos na absorção de fósforo e enxofre quando baixas concentrações de Se foram fornecidas. Observou-se que a aplicação de até 16,77 e 7,54 µmol L-1 de Se com as fontes selenato e selenito, respectivamente, proporcionaram os maiores incrementos na produtividade do repolho, e mesmo com a redução da produtividade com concentrações acima destas, os valores foram maiores que o tratamento controle. Isso indica que o Se foi benéfico ao repolho, pois não reduziu a sua produção. Verificou-se que a biofortificação foi eficiente para ambas as cultivares de repolho, que absorveram e acumularam Se na cabeça de repolho em função do incremento de Se, tanto com selenato como selenito.
The objective of this research was to evaluate concentrations of selenium (sodium selenate and selenite) in the growth, production and biofortification of two cabbage cultivars. Two experiments were carried out in greenhouse under hydroponic system, from July to November, 2014, at UNESP, Jaboticabal-SP campus. The experiments differed according to the source of selenium (Se) used (sodium selenate and selenite). In both experiments two factors were evaluated: two cabbage cultivars ('Fênix' and 'Red Dinasty') and five concentrations of Se (0, 5, 15, 30 and 60 μmol L-1) in the nutrient solution. The experimental was a randomized block design, with 2 x 5 factorial and four replications. The variables analyzed were the content and accumulation of Se in the root and shoot cabbage, evaluating area, diameter, length, density and dry mass in the root, cabbage yield, stem and cabbage head, and the content accumulation of nitrogen, phosphorus and sulfur in the cabbage shoot. Selenate and selenite sources promoted the growth of cabbage roots due to increases in area, diameter, length and root density at low concentrations of Se applied. The increase in root dry mass production was probably due to higher root growth, which was influenced by the supply of Se. The dry mass of the stem was different only between the cabbage cultivars with application of selenate or selenite. The nitrogen content presented differences only among the cultivars when the selenite source was used. Both S sources also provided increases in phosphorus and sulfur absorption when low concentrations of if were provided. It was observed that the application of up to 16,77 and 7,54 μmol L-1 of Se with selenate and selenite sources, respectively, provided the greatest increases in cabbage yield, and even with the reduction of productivity with concentrations above these, the values were higher than the control treatment. These indicate that the Se was beneficial to the cabbage, since it did not reduce its production. It was verified that biofortification was efficient for both cabbage cultivars, which absorbed and accumulated Se in the cabbage head as a function of the increase of Se, with both selenate and selenite.
The objective of this research was to evaluate concentrations of selenium (sodium selenate and selenite) in the growth, production and biofortification of two cabbage cultivars. Two experiments were carried out in greenhouse under hydroponic system, from July to November, 2014, at UNESP, Jaboticabal-SP campus. The experiments differed according to the source of selenium (Se) used (sodium selenate and selenite). In both experiments two factors were evaluated: two cabbage cultivars ('Fênix' and 'Red Dinasty') and five concentrations of Se (0, 5, 15, 30 and 60 μmol L-1) in the nutrient solution. The experimental was a randomized block design, with 2 x 5 factorial and four replications. The variables analyzed were the content and accumulation of Se in the root and shoot cabbage, evaluating area, diameter, length, density and dry mass in the root, cabbage yield, stem and cabbage head, and the content accumulation of nitrogen, phosphorus and sulfur in the cabbage shoot. Selenate and selenite sources promoted the growth of cabbage roots due to increases in area, diameter, length and root density at low concentrations of Se applied. The increase in root dry mass production was probably due to higher root growth, which was influenced by the supply of Se. The dry mass of the stem was different only between the cabbage cultivars with application of selenate or selenite. The nitrogen content presented differences only among the cultivars when the selenite source was used. Both S sources also provided increases in phosphorus and sulfur absorption when low concentrations of if were provided. It was observed that the application of up to 16,77 and 7,54 μmol L-1 of Se with selenate and selenite sources, respectively, provided the greatest increases in cabbage yield, and even with the reduction of productivity with concentrations above these, the values were higher than the control treatment. These indicate that the Se was beneficial to the cabbage, since it did not reduce its production. It was verified that biofortification was efficient for both cabbage cultivars, which absorbed and accumulated Se in the cabbage head as a function of the increase of Se, with both selenate and selenite.
Descrição
Palavras-chave
Brassica oleracea var. capitata, selenato, selenito, selenate, selenite