Uso de bioestimulante no capim-corrente submetido ao estresse hídrico

Abstract

The use of biostimulants in plants promotes activities similar to phytohormones. Thus, the objective was to evaluate the influence of a biostimulant on the growth and accumulation of phytomass in plants of urocloa grass (Urochloa mosambicensis), submitted to water stress conditions. The test was conducted from September to December 2019, in the experimental area of the Study Group on Forage (GEFOR), of the Federal Rural University of Pernambuco, Academic Unit of Serra Talhada (UFRPE-UAST). The design used was in randomized blocks, in a 4x2 factorial scheme, with four levels of water replacement, based on the culture evapotranspiration (ETc): 25%.ETc, 50%.ETc, 75%.ETc and 100%.ETc and two levels of a commercial Acadian® biostimulant (0 and 8 ml per liter), with four replications, totaling 32 experimental units, represented by vessels. Urocloa grass growth was monitored every seven days during a growth cycle. The structural characteristics were evaluated: plant height and width, stem length and diameter, number of: total tillers, fully expanded leaves, expanding leaves and senescent leaves. The leaf area was estimated, nondestructively, based on the linear dimensions of the length and width of the leaf blade. At the end of the cycle, the fresh and dry mass of the morphological components and the total aerial part were determined. The evaluation data were subjected to the normality test, homoscedasticity and analysis of variance by Test F. Since F was significant, the treatment means were compared using the Tukey test at 5% probability. The results showed that for most of the morphometric variables there was no interaction between the levels of biostimulant and the ETc levels. In the absence of the biostimulant, the largest stem diameter was obtained, except for 100% .ETc. Urocloa grass has a moderate tolerance to water stress.