Hydroponic wheat production using fresh water and treated wastewater under the semi-arid region

Abstract

The use of alternative water sources such as tertiary treated wastewater is considered very important for growing crops due to irrigation water scarcity, particularly in arid regions like the UAE. Treated wastewater contains nutrients that are essential for the cultivation of nutritively important crops. In the present study, we evaluated and compared the effect of differently treated wastewater samples using an auto-pot watering hydroponic system. The growth solution was prepared using well water (H), and treated wastewaters collected from different geological areas Abu Dhabi (H1) and Al Ain (H2). The study was carried out with two wheat varieties (ESWYT and SAWYT)) obtained from the CIMMYT Genetic Resource Centre. Temperature, pH, and electrical conductivity (EC) of the growth solutions were monitored. Twelve weeks after planting, the wheat plants were harvested and root, shoot and spike biomasses were measured. The H2 treatment had a positive impact on wheat growth and different morphological characters, especially for SAWYT variety. Moreover, for both the varieties, highest grain yield, total chlorophyll and carotenoids were observed with H2 treatment. Between the treatments H1 and H2, there was only a slight variation in protein content and fiber content for both the wheat varieties. The growth of wheat plants was inhibited by H1 treatment due to the high electrical conductivity of the wastewater. The final kernel was analyzed and the levels of Ca, K and P were higher in plants grown in H2. The study revealed appreciable results suggesting that the hydroponic effluents are a strong fertilizer source. In addition, the use of treated wastewater in the irrigation of wheat crops in hydroponic systems has been considered as a useful alternative wastewater disposal method without the possibility of accumulation of heavy metals in the soil.