SUPLEMENTAÇÃO FOLIAR COM AMINOÁCIDOS: IMPACTOS NO METABOLISMO DA CLOROFILA E NA PRODUTIVIDADE DO ALGODÃO HERBÁCEO

Abstract

Herbaceous cotton is a crop of considerable economic and historical importance, widely cultivated in over 70 countries and responsible for generating billions of dollars in international trade. In Brazil, cotton productivity has increased due to the adoption of more efficient cultivars and improved management practices; however, low-fertility soils, such as those prevalent in the Cerrado region, remain a significant constraint. In this context, foliar fertilization, particularly when associated with amino acids, has emerged as a promising strategy, as it enhances nutrient uptake, improves stress tolerance, and promotes plant productivity. Therefore, this study aimed to evaluate the effects of foliar application of an amino acid-based biostimulant on the physiological and yield-related characteristics of cotton plants. The experiment was conducted using a randomized complete block design, with six treatments and four replications. Treatments consisted of six doses of an amino acid-based biostimulant (0, 200, 400, 600, 800, and 1000 mL ha⁻¹), applied via foliar spraying at the flowering phenological stage (R1). The cotton cultivar used was FM 975 WS. The evaluated variables included SPAD index, dry matter accumulation, number of bolls per plant, and yield. Overall, the application of biostimulants showed potential to enhance both physiological performance and yield of cotton plants when applied at appropriate rates. It can be concluded that foliar application of the biostimulant improves cotton performance, with recommended application rates ranging from 600 to 800 mL ha⁻¹.