Agronomic performance of cauliflower (Cv. Cindy) under different boron rates and irrigation levels in the Cerrado–Amazon Ecotone, Brazil

Water availability and boron (B) supply are interdependent factors that strongly influence cauliflower production, particularly in the Cerrado–Amazon Ecotone, where high temperatures and irregular rainfall may limit nutrient uptake. This study assessed the agronomic performance of cauliflower cv. Cindy under different boron rates and irrigation depths. The experiment was carried out in the Cerrado–Amazon Ecotone, Brazil, using a randomized complete block design in a 5 × 4 factorial arrangement with five irrigation depths (2, 3, 4, 5, and 6 mm day−1) and four B rates (0, 2, 4, and 6 kg ha−1), with three replications (blocks), totaling 60 experimental units (plots). Each plot contained 18 plants spaced 0.90 × 0.90 m, with the four central plants used for evaluations. Variables assessed included fresh biomass (FB), total curd yield (TCY), marketable curd yield (MCY), curd diameter (CD), stalk diameter (SD), crop cycle duration (CCD), and curd deformation (CDF). No significant interaction between B and irrigation was observed (p > 0.05). B application increased FB, TCY, and MCY, with the maximum MCY (12.15 t ha−1) estimated at 4.56 kg ha−1, while extreme doses (0 and 6 kg ha−1) reduced commercial quality. Irrigation had a significant effect on all variables, and 6 mm day−1 resulted in the best crop performance, with means of 1,106.51 g (FB), 13.66 t ha−1 (TCY), 10.50 t ha−1 (MCY), 18.56 cm (CD), and only 0.99% CDF. These results show that adequate soil moisture enhances B uptake and improves yield components, even in the absence of a significant interaction between factors.