Estresse salino e bioestimulante vegetal no crescimento, produção e fisiologia do manjericão.

• Autor(a) principal: Sousa, Leonardo Vieira de
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/14739
• topic: Ocimum basilicum L.; Lamiaceae; Salinidade hídrica; Hormônios vegetais; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA

The cultivation of basil (Ocimum basilicum L.) may be an economical alternative for the Brazilian northeast, however, some areas of this region have excess salts in the water. The application of growth regulators may mitigate the deleterious effects of saline stress. The objective of this work was to evaluate the action of biostimulant on the basil culture submitted to saline stress. The experiment was conducted at the Federal University of Paraíba, Campus II, Areia, Paraíba, Brazil. The experimental design was a randomized block, in a factorial of 5 x 5, combined according to the Central Composite matrix of Box, referring to five electrical conductivities of the irrigation water and five doses of plant growth regulator, with minimum values (- α) and (α), respectively 0.5 and 6.0 dS m-1 and 0.0 and 10.0 mL L-1, totaling nine treatments, with four replications and two plants per plot. Plants were evaluated for development, gas exchange, chlorophyll fluorescence and chlorophyll content as well as soil chemical analysis. There was no interaction between the electrical conductivities of the irrigation water and the doses of plant growth regulator for any studied variable. A statistical difference was found between the electrical conductivities for all growth variables. As for the physiological variables, there was a difference between the electrical conductivities for the chlorophyll indices, initial fluorescence, potential and effective quantum yield of photosystem II, internal CO2 concentration, water use efficiency, water use efficiency and instantaneous carboxylation efficiency. Regarding the soil chemical attributes, an increasing response occurred due to the increase of the electrical conductivities for all variables studied. The salinity of the water causes reduction of the development parameters of basil. Applications of biostimulant have no effect on the growth and physiology of basil when the plants are irrigated with salt water. Saline stress causes changes in potassium and sodium contents, as well as increase in the electrical conductivity of the saturation extract, cation exchange capacity, base sum and base saturation.