Estresse hídrico em Alecrim-pimenta (Lippia Sidoides Cham.): aspectos fisiológicos e produtivos

Abstract

This study aimed to characterize the culture of rosemary-pepper (Lippia siodides Cham.) face to water availability, evaluating the productive behavior and physiology of the plant. The experiment was conducted in lysimeter drainage, at the Institute of Agricultural Sciences of the Federal University of Minas Gerais, in the city of Montes Claros, Minas Gerais State, in two stages, sensitivity to water stress and suppression of irrigation before harvest. To determine the sensitivity to water stress, the work was conducted evaluating different irrigation slides (0,5; 0,75; 1,0; 1,2; 1,4; 1,65 e 1,9x), Evapotranspiration of reference (ETo), with three replications, arranged in randomized blocks, in a crop cycle of 120 days. The ETo was determined by the Penman Monteith method, with the necessary data collected in automatic weather station present at the experimental area. They were determined the production of fresh and dry mass and essential oil content, Evapotranspiration culture (ETc), Evapotranspiration real of the culture (ETR) and the sensitivity of the culture to the water stress (Ky). The results indicated the rosemary-pepper sensitive to the water stress before harvest, with average values of 1.57 for fresh matter and 1.29 for essential oil content. The average production of dry mass per plant was 75 g plant-1. The second step consisted of suppression irrigation for 8, 6, 4, 2 and 0 days before harvest in a cycle of 270 days, keeping the soil at field capacity, evaluated the essential oil content and of the flavonoides. It was observed the tension values between -0.41 and -0.66 MPa, and production losses in essential oil content of 50% with the increment of -0.3 MPa. The data were submitted to the Tukey average test at 5% level of probability. The treatment with 8 days of stress before harvest showed leaf temperature above the other treatments. The other parameters as content of flavonoids, essential oil production, fresh and dry matter didn't show significance when compared.