Investigating the Interaction of Deficit Irrigation and Magnetic Water on Yield, Yield Components, and Water Productivity of Marigold

To investigate the interaction of magnetic water and deficit irrigation on yield and yield components of marigold, a factorial experiment was conducted in a completely randomized design in the research greenhouse of the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2019, using pot culture with 3 replications. Treatments included 4 irrigation levels (100%, 85%, 70%, and 55% of field capacity) and 2 types of water (normal water and magnetic water). The results showed that different levels of irrigation on all traits (except physical water productivity which was significant at a 5% level) were significant (P <0.01). Effects of magnetic water on the dry weight of lateral branches and flowers, number of flowers and physical water productivity were significant (at P <0.01); and on the dry weight of flowering stems and leaves, number of leaves and lateral branches were also significant (at P <0.05). The interaction effect of the studied treatments was significant (P <0.01) on the number of leaves; and on the dry weight of roots, flowers, and flowering stems (P <0.05). The highest dry weights of leaves and flowering stems, number of flowers, number of leaves and lateral branches, height and physical water productivity were in irrigation with 100% field capacity and were, respectively, 1.77 and 0.37 g/plant, 7 and 6, 18.4 cm and 0.186 kg/m3. Also, reducing irrigation water by 15%, 30%, and 45% reduced the number of flowers by 25.7%, 32.8%, and 54.3%; and the physical water productivity by 18.8%, 21.5%, and 24.2%, respectively. The highest dry weight of flowers, roots, and lateral branches were observed in magnetic water + irrigation with 100% field capacity, as 0.29, 0.5, and 0.74 g/plant, respectively. The results showed that using a magnetic field increased flower yield and water productivity of Marigold plants under water stress. In this study, the best treatment was 0.6 teslas magnetized water+ 100%FC. However, to apply these stresses at the field level, more research is needed.