Mango floral induction: nutritional strategies with molybdenum and nitrate to improve flowering

Floral induction in mango enables flowering at any time of the year. However, among the stages that constitute floral induction, foliar nitrate application requires optimization due to the low absorption efficiency, which may occur under molybdenum deficiency. Molybdenum is a key nutrient for activating the enzyme nitrate reductase, which regulates nitrate assimilation in plants. This study aimed to optimize nitrate application for floral induction in ‘Tommy Atkins’ mango trees through molybdenum supplementation. The experiment was carried out in the Sub-Middle São Francisco Valley, Brazil, between 2022 and 2024. A randomized block design was used, with five replications and six plants per plot. Treatments were arranged in a 4 × 2 factorial scheme with four molybdenum concentrations (0.000, 0.100, 0.225, and 0.375 g L−1) and two calcium nitrate concentrations (conventional and adjusted). Molybdenum supplementation increased flowering by up to 33.5% and yield by up to 162.5%, depending on nitrate concentration. Molybdenum availability is a key factor regulating nitrogen assimilation efficiency during floral induction in mango. Its supplementation improved flowering and yield, allowing a reduction in nitrate application without compromising productivity. The combinations of 0.100 g L−1 Mo with conventional nitrate and 0.225 g L−1 Mo with reduced nitrate were the most effective for optimizing reproductive performance. These findings support molybdenum supplementation as a practical strategy to improve nitrogen use efficiency and fertilization management in mango production systems.