EARLY PHENOLOGICAL AND GROWTH RESPONSES OF COTTON (GOSSYPIUM HIRSUTUM L.) TO HUMIC-BASED BIOSTIMULANTS UNDER VARIABLE PLANTING DENSITIES

Abstract

The regulation of early plant development plays a decisive role in determining the productivity and adaptability of cotton under intensive cultivation systems. This study investigates the influence of humic-based biostimulants—Ekogumin, a soil-applied humic acid formulation, and Novogumin, a foliar-applied fulvic acid complex—on the phenological development of cotton  under varying planting densities. Field experiments were conducted in the irrigated conditions of the Fergana Valley during the 2025 growing season, employing a factorial design that included twelve treatment combinations across three plant population densities.

Phenological parameters, including plant height, number of branches, flowering intensity, and boll formation, were systematically recorded from June to September. The results demonstrate that humic-based treatments significantly accelerate both vegetative and reproductive development. The combined application of Ekogumin and Novogumin produced the most pronounced effects, enhancing plant height by up to 10% during early growth stages and increasing reproductive indicators by 5–10% compared to untreated controls. These improvements were especially evident during the transition from vegetative to reproductive phases, suggesting enhanced physiological activity and metabolic efficiency. The findings confirm that humic substances play a critical role in optimizing growth dynamics and improving plant adaptability under conditions of increased population density.