Hydrogen peroxide and saline nutrient solution in hydroponic zucchini culture

• Autor(a) principal: Dantas, Maila Vieira
• Data de Publicação: 2022
• Outros Autores: Lima, Geovani Soares de, Gheyi, Hans Raj, Silva, Luderlândio de Andrade, Silva, Petterson Costa Conceição, Soares, Lauriane Almeida dos Anjos, Lopes, Iracy Amélia Pereira, Roque, Iara Almeida
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Semina. Ciências Agrárias (Online)
• Texto Completo: https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/43137
• topic: Cross-tolerance; Cucurbita pepo L.; ROS; Salinity.; Cucurbita pepo L.; Salinidade; Tolerância cruzada; EROs.

Saline water has been used in irrigation due to the limited availability of fresh water, especially in arid and semi-arid regions. However, the use of this type of water can affect crop growth and development. Studies have tested the use of chemical conditioners to minimize the negative effects of salinity on plants. In this scenario, the present study examined the role of hydrogen peroxide in mitigating the negative effects of salt stress on zucchini plants grown in a hydroponic system. The study was carried out in a greenhouse in Pombal - PB, Brazil. The NFT (nutrient film technique) hydroponic system was employed. A randomized complete experimental design was set up with a 4 × 4 factorial arrangement consisting of four levels of electrical conductivity in the nutrient solution (ECns: 2.1 [control], 3.6, 5.1, and 6.6 dS m-1) and four concentrations of hydrogen peroxide (H2O2: 0, 20, 40, and 60 uM), in three replicates. Foliar spraying with H2O2 at 60 and 40 uM associated with the nutrient solution of 2.1 dS m-1 increased stem diameter and root length, respectively, at 47 days after transplanting. However, at ECns higher than 2.1 dS m-1, the application of H2O2 at the concentrations of 60 and 40 uM intensified salt stress, reducing stem diameter and root length. Nutrient solution salinity levels above 2.1 dS m-1 reduce photosynthetic pigments; the number of leaves; leaf area; the length of the main branch; and the dry biomass of stems, leaves, and roots of zucchini plants. Chlorophyll b and carotenoid contents are the variables most sensitive to changes in salinity levels.