Physiological responses of the beet crop under agricultural environment and saline stress
Revista Ambiente E Água
Physiological responses of the beet crop under agricultural environment and saline stress
Autor Correspondente: José Thomas Machado de Sousa | [email protected]
Palavras-chave: Beta vulgaris L., gas exchange, salinity levels
Resumos Cadastrados
Resumo Português:
Os efeitos deletérios dos sais nas plantas expostas a altas radiações solares tendem a ser mais acelerados em razão do aumento de íons tóxicos na parte aérea vegetal, consequentemente, os processos fisiológicos e bioquímicos serão afetados. No entanto, esses efeitos podem ser minimizados com a utilização de estratégias de manejo, como o uso de tela de sombreamento e ambiente protegido. Nesse sentindo, objetivou-se avaliar as repostas fisiológicas da cultura da beterraba cultivada em diferentes ambientes e irrigada com águas salinas. O experimento foi conduzido em delineamento experimental inteiramente casualizado, fazendo uso do esquema fatorial 3 × 2, equivalente a três ambientes (PS = pleno sol; TS = telado de sombreamento aberto nas laterais e AP = ambiente protegido) e duas condutividades elétricas da água de irrigação (0,5 e 6,2 dS m-1), com quatro repetições. Aos 45 dias após a semeadura (DAS) foram analisadas as seguintes variáveis: condutância estomática, fotossíntese liquida, transpiração, concentração interna de CO2, temperatura foliar, eficiência instantânea no uso da água, eficiência da carboxilação instantânea, eficiência intrínseca do uso da água e índice relativo de clorofila. A irrigação com água de maior salinidade afetou negativamente a condutância estomática, a fotossíntese liquida, a temperatura foliar, eficiência instantânea no uso da água de plantas de beterrabas cultivadas em ambiente pleno sol. O ambiente protegido e o telado aberto nas laterais atenuou parcialmente os efeitos deletérios da salinidade.
Palavras-chave: Beta vulgaris L.; níveis de salinidade; trocas gasosas
Resumo Inglês:
The deleterious effects of salts on plants exposed to high solar radiation tend to be more accelerated due to the increase of toxic ions in the aerial plant part. Consequently, the physiological and biochemical processes will be affected. These effects can be minimized, however, with the use of management strategies, such as the use of a shading screen and a protected environment. In this sense, the objective of this work was to evaluate the physiological responses of sugar beet cultivated in different environments and irrigated with saline water. The experiment was conducted in an experimental design entirely randomized, using the factorial scheme 3 × 2, equivalent to three environments (FS = full sun; SSOS = shading screen open on the sides and PE = protected environment) and two electrical conductivities of the irrigation water (0.5 and 6.2 dS m-1), with four repetitions. At 45 days after sowing (DAS) the following variables were analyzed: stomatal conductance, liquid photosynthesis, transpiration, internal CO2 concentration, leaf temperature, instantaneous water use efficiency, instantaneous carboxylation efficiency, intrinsic water use efficiency, and relative chlorophyll index. Irrigation with water of higher salinity negatively affected stomatal conductance, net photosynthesis, leaf temperature and instantaneous water use efficiency of sugar beet plants grown in a full sun environment. The protected environment and open shading on the sides partially mitigated the deleterious effects of salinity.
Keywords: Beta vulgaris L., gas exchange, salinity levels
Resumo Espanhol:
The deleterious effects of salts on plants exposed to high solar radiation tend to be more accelerated due to the increase of toxic ions in the aerial plant part. Consequently, the physiological and biochemical processes will be affected. These effects can be minimized, however, with the use of management strategies, such as the use of a shading screen and a protected environment. In this sense, the objective of this work was to evaluate the physiological responses of sugar beet cultivated in different environments and irrigated with saline water. The experiment was conducted in an experimental design entirely randomized, using the factorial scheme 3 × 2, equivalent to three environments (FS = full sun; SSOS = shading screen open on the sides and PE = protected environment) and two electrical conductivities of the irrigation water (0.5 and 6.2 dS m-1), with four repetitions. At 45 days after sowing (DAS) the following variables were analyzed: stomatal conductance, liquid photosynthesis, transpiration, internal CO2 concentration, leaf temperature, instantaneous water use efficiency, instantaneous carboxylation efficiency, intrinsic water use efficiency, and relative chlorophyll index. Irrigation with water of higher salinity negatively affected stomatal conductance, net photosynthesis, leaf temperature and instantaneous water use efficiency of sugar beet plants grown in a full sun environment. The protected environment and open shading on the sides partially mitigated the deleterious effects of salinity.
Keywords: Beta vulgaris L., gas exchange, salinity levels
