Produtividade da água na produção e crescimento de Melissa officinalis L. irrigada com água tratada magneticamente

Abstract

Melissa (Melissa officinalis L.) is a plant with active principles of medicinal use of soothing, diuretic and sedative, with emphasis on the production of essential oil, widely used for antioxidative, antibiotic, antifungal, antibacterial and sedative activity. One technique that has been shown to be promising in different areas, including agricultural area, is the use of magnetically treated water. The technique consists of a process in which water is subjected to a constant magnetic field, causing changes in its physical and chemical properties. The objective of the present study was to evaluate the growth and water productivity in relation to the leaves dry matter production and production of essential oil of Melissa officinalis produced in a greenhouse, irrigated by dripping with conventional and magnetically treated water. The variation in the evapotranspiration was estimated by weighing lysimeters, using 25%, 75%, 100% and 125% of the evapotranspiration of the crop (Etc) applied with magnetically treated water (MTA) and conventional water (CW). Plant height, stem diameter, leaf dry mass, leaf area, electrical conductivity and pH of the drained solution, crop yield and yield of the essential oil, and water productivity in relation to dry leaf mass production and e the essential oil production were evaluated. The results showed that the variables of stem diameter, water productivity in relation to leaf dry mass production and in relation to essential oil production presented a significant difference, through the analysis of variance, in depending on the type of water used. The treatments that received 25% of ETc for both MTA and CW showed a significant difference, with lower values in relation to the others for the variables plant height, stem diameter, growth rate at plant height, leaf area, leaf dry mass, and essential oil production, and higher for essential oil yield and water productivity compared to essential oil production. On the other hand, the variables electrical conductivity and pH did not present any significant difference between the treatments. Taking into consideration the evaluated parameters, the treatment of 75% of the ETc irrigated with CW it was the one with best results.