Effect of boron fertilization on nutrition and nutrient export in Arabica coffee plants

Abstract

The formation of the cell wall, membrane stability, and the reproductive phase influence the formation of coffee beans. The objective of this work was to evaluate the effect of boron fertilization on the assimilation and export of macronutrients and boron in Coffea arabica, aiming to understand its influence on the nutritional status of the crop. The experiment was conducted in the 2023/2024 growing season in Santo Antônio do Amparo (MG), in a randomized block design with five doses of B (0; 1.5; 3.0; 4.5 and 6.0 kg ha⁻¹) and five replications. The attributes evaluated were nutrient content in leaves, beans, and nutrient export. Leaf sampling was done according to the recommendations for the crop. Nutrient export was calculated using productivity data and nutrient concentrations in the beans. The application of boron to the soil did not alter the foliar macronutrient content, which remained within the adequate range for the crop. In the grains, there was no effect of B doses on N and Mg contents, while P and K showed responses, with a predominantly quadratic behavior at doses close to the average of 2.4 kg ha⁻¹ of B. S showed a decreasing linear behavior, with a reduction of approximately 27%. The accumulation and export of nutrients were influenced by B doses, with increases up to values ​​between 3.0 and 4.5 kg ha⁻¹. For N, P, Mg, S, and B, a quadratic response was observed, with maximums at the average of 3 kg ha⁻¹ of B. K was the most exported nutrient, with values ​​between 122 and 146 kg ha⁻¹, with a maximum point at the dose of 3.4 kg ha⁻¹. Ca showed a linear increase as the dose of boron in the soil increased. The dose of 6.0 kg ha⁻¹ did not provide additional gains, indicating a limitation to increasing boron doses.