Magnetically treated water affects Melissa officinalis L growth, nutritional status and essential oil compounds

Abstract

Drip irrigation is one of the agricultural techniques mostly used to grow a wide variety of vegetable crops. Studies focused on improving this technique based on using magnetized water, as well as on investigating its effects on medicinal plant production processes, remain incipient in the literature. Some benefits of this technique are the optimization of the quality and quantity of irrigation water, economy of the water absorbed by the plants, improvement in the vegetative growth and productivity, reduction of the use of fertilizers and the greater availability of nutrients in the soil for crops compared to irrigation using conventional water. Thus, the aim of the current study is to assess the effect of different magnetized and non-magnetized water irrigation levels on Melissa officinalis growth, nutritional status and essential oil compounds in plants grown in protected environment. The experimental design consisted of completely randomized design with two water types (magnetized and non-magnetized) and four irrigation levels (25%, 75%, 100% and 125% of crop evapotranspiration - ETc) with four replications. Irrigation conducted with different magnetized water levels had significant effect on the accumulation of nitrogen, phosphorus, sulfur, and of all micronutrients in plants’ leaves, and on soluble protein contents. The study also demonstrated significant effects of magnetically treated irrigation water on major chemical compounds such as citral (neral + geranial) and citronellal on the leaves of lemon balm plants. Different water levels significantly affected plant dry weight production parameters. In this study it was shown that the plant treated with magnetized water required less amount of water applied being a promising potential in saving water resources that will be of significant importance in the future. Overall, the results need to be further tested under field conditions to assess the usefulness of magnetic irrigation water treatment.in cultivation with medicinal, aromatic and spice plants. It is hoped that this study can contribute to improving water management, reducing the environmental impact without implying great costs for the producer.