Physiological changes of bell pepper grown under nutrient solutions prepared with brackish water and H2O2 concentrations

• Published in: Comunicata Scientiae Vol. 13; pp. 1 - 11
• Main Authors: Furtado, Guilherme de Freitas, do Nascimento, Ronaldo, Santos, José Amilton, Chaves, Lúcia Helena Garófalo, de Souza, Felipe Guedes, Gheyi, Hans Haj
• Format: Journal Article
• Language: English
• Published: Bom Jesus Comunicata Scientiae 01.01.2022
• Subjects: Abiotic stress; Agricultural engineering; Agricultural production; Arid regions; Arid zones; Brackish water; Carotenoids; Chlorophyll; Chlorophyll a; Electrical conductivity; Electrical resistivity; Foliar applications; Gas exchange; Hydrogen peroxide; Hydroponics; Irrigation; Irrigation water; Mineral nutrients; Nutrient concentrations; Nutrient solutions; Photosynthesis; Photosynthetic pigments; Pigments; Rain; Rain water; Salinity; Semi arid areas; Semiarid lands; Vegetables; Brazil
• ISSN: 2179-9079; 2177-5133
• DOI: 10.14295/CS.v13.3702

Adopting strategies to mitigate the negative effects of salt excess in irrigation water is essential to maintain production systems, especially in semi-arid regions. From this perspective, this study aimed to evaluate the gas exchange and photosynthetic pigments of hydroponic bell pepper grown under different water combinations (brackish water and rainwater) and foliar application of hydrogen peroxide (H2O2). The study was conducted in a protected environment at the Agricultural Engineering Academic Unit of the Federal University of Campina Grande, Brazil. The experiment was set up in a completely randomized design with 12 treatments and a 4 x 3 factorial arrangement with five replications, each consisting of four brackish water and rainwater combinations (10%/90%; 20%/80%; 30%/70%;40%/60%) and three H2O2 concentrations: 0.0 (control), 7.5 μM, and 15 μM supplied via foliar application every seven days starting 42 days after sowing (DAS). The application of 15.0 μM of H2O2 in bell pepper plants grown with the nutrient solution containing the 30%/70% and 40%/60% combinations between brackish water and rainwater increased photosynthesis 24 days after sowing and increased stress 61 days after sowing. After 61 DAS, the highest gs and E values of bell pepper grown with the nutrient solution at the electrical conductivity of 2.72 dS m-1 (10%/90%) were obtained by applying 15.0 μM of H2O2. The contents of chlorophyll "a", "b", total chlorophyll, and carotenoids of bell pepper plants showed deleterious effects caused by the salinity of the nutrient solution, mitigated by the exogenous application of 15 μM hydrogen peroxide.