Effect of Detergents in Irrigation Water on the Productivity and Chemical Composition of Spring Wheat Grain and Straw

Abstract

The effects of used laundry detergent solution (laundry greywater) on the productivity, technological grain quality, and chemical composition of spring wheat straw of the Myronivchanka cultivar were investigated. The study aimed to assess plant responses to irrigation with laundry greywater of different concentrations and to evaluate its potential use as an alternative water source under conditions of water scarcity. The research was conducted over two years as a vegetation experiment in a soil tub. The experimental design included a control treatment irrigated with tap water and two treatments irrigated with laundry detergent solutions of different concentrations. Plant phenotype and height, grain weight and yield, technological grain quality parameters, as well as the contents of major nutrients, heavy metals, and trace elements in the straw were evaluated. The results showed that the tested solutions did not cause visible signs of toxic effects on the growth and development of spring wheat. Grain weight and plant height generally remained comparable to the control. Irrigation with the less concentrated solution resulted in the highest average grain yield over the study period, whereas the higher detergent concentration had a positive effect on technological grain quality, particularly on protein and gluten contents. Agrochemical analysis of the straw revealed changes in the accumulation of individual nutrients depending on the composition of the irrigation water. At the same time, the concentrations of the analysed heavy metals and trace elements did not exceed the maximum permissible levels, while the accumulation of several elements was lower in the laundry greywater treatments than in the control. The findings indicate that, under the conditions of the vegetation experiment, irrigation with water containing the tested concentrations of laundry detergent did not adversely affect the main growth and productivity parameters of spring wheat and did not result in excessive accumulation of the analysed heavy metals in the straw. These results support the need for further investigation into the potential reuse of household laundry greywater in irrigation systems, with particular consideration of its chemical composition and the duration of application.