The effects of foliar application of selenium sources at different soybean development stages, focusing on leaf morphology, development, and grain yieldLisboa, Lucas Aparecido Manzani (Avtor) Jonack, Marcos Vinícius (Avtor) Jatoba, Matheus Ferreira (Avtor) Siqueira, Hiago Rocha (Avtor) Pinow, Vinicius de Lima (Avtor) Glycine max L.micronutrientplant growthgrain productionThis study aimed to understand the effects of foliar application of selenium sources at different soybean development stages, focusing on leaf morphology, development, and grain yield. The experiment was carried out in December 2024, at the “Capão da Onça” School Farm of the State University of Ponta Grossa (UEPG), in the South-Central region of the State of Paraná, Brazil. The experimental design was a completely randomized block (RBC) design in a 2 x 3 factorial arrangement, where the first factor was application at the Vegetative7 and Reproductive1 development stages, interacting with the selenium sources: selenate, selenite, and absence of the nutrient, totaling 6 treatments with four replicates, totalling 24 plots The selenium influences soybean plant development. The use of 10 µM selenate improves soybean crop development, grain yield, palisade parenchyma thickness, xylem diameter, phloem diameter, stomatal density and stomatal functionality. Selenium application at the Vegetative7 development stage can result in increased plant height, palisade parenchyma thickness, and phloem diameter.20262026-03-11 10:25:34Članek v reviji180560UDK: 633ISSN pri članku: 1854-1941DOI: 10.14720/aas.2026.122.1.24344COBISS_ID: 271200771sl