Resposta da cana-de-açúcar e ambiente rizosférico a aplicação de bioestumulantes

Abstract

The cultivation of sugarcane in Brazil is of great importance for agribusiness, and its productivity needs to meet the new demands for renewable sources. Biostimulants are substances that, when applied to plants, can alter various specific metabolic and physiological processes, acting at different stages of crop development. The objective of this work was to evaluate the effect of a biostimulant on the distribution of the root system of the cane plant; enzymatic activity in the soil; on microbial diversity at the rhizosphere level, as well as on sugarcane growth and development. The study was carried out in a commercial area of sugarcane cultivation in the Coastal Tablelands, Paraíba. The experiment was set up in an area of six hectares, divided into two areas of three hectares, with one area receiving the application of Viusid Agro® and the other the management adopted by the company. Three collections were carried out, in the intense growth phase of the crop (120 DAP) (240 DAP), culture maturation phase and the last collection in August 2020, 30 days after the sugarcane harvest. At 402 days after planting, manual cutting was performed to evaluate the technological variables (TCH, Brix, ATR and Pol %). The activities of the enzymes urease, acid phosphatase and general enzymatic activity of the soil (hydrolysis of fluorescein diacetate - ADF) were evaluated. In the observed results, Viusid Agro® provided a significant increase in the productivity of the cane-plant, with an increment of 20.19 t ha-1, when compared to the control treatment, greater uniformity of the cane field, in germination, increase in rooting, reduction of failures and competition among the clumps themselves, and tillering patterns. ADF hydrolysis values were higher in the three collections in the area with VIUSID Agro®. Urease did not show significant differences between the area where the VIUSID Agro® biostimulant was applied and the control at 120 days after planting and 30 days after harvesting. The maximum activity of acid phosphatase was in the control of 1638.8 μg p-nitrophenol h-1 g-1 240 days after planting.