Ação do 24-EPBL no comportamento de macronutrientes em plantas de sorgo (Sorghum bicolor L. Moench) submetidas ao déficit hídrico e reidratação

Abstract

Sorghum (Sorgum bicolor) is a cereal originating from Africa belonging to the Poaceae family, it is a forage crop with a C4 photosynthetic mechanism that stands out for being able to adapt to different environments, managing to produce even in unfavorable circumstances, mainly under conditions of water deficiency, as it is a more efficient cereal, when compared to others, in absorbing water and nutrients from the soil, which means that it can make better use of the available water and guarantee greater adaptability to different regions of the country. Brassinosteroids (BRs) are endogenous plant hormones, which act as resistance inducers and have the ability to promote, inhibit or alter physiological processes in plants facing water deficit conditions. The objective of the work was to analyze the attenuating effect of the Brassinosteroid hormone in the form of 24-epibrassinolide on Sorghum plants (Sorghum bicolor L. Moench) subjected to water deficit. The experiment was conducted in a greenhouse belonging to UFRA (Federal Rural University of the Amazon) in Belém, with a completely randomized experimental design (DIC), with a 2 x 3 x 5 factorial scheme, with two water conditions (water deficit and rehydration) and three dosages of Brassinosteroid in the form of 24-epibrassinolide (0 nM, 50 nM and 100 nM) with 5 repetitions, totaling 30 experimental units. Macronutrients (N, P, K, Ca and Mg) were analyzed in the Soil Physics laboratory of the research campus of Museu Paraense Emílio Goeldi. The application of 24- epibrassinolide was more effective in stressed plants, with no significant differences between treatments during irrigation suspension. Rehydrated plants maintained nutrient levels similar to control plants, regardless of BR application.