Assessment of plant mineral nutrition concentrations of tomato irrigated with brackish water and RO concentrate
Hui Yang, Manoj K. Shukla, Taisheng Du
Abstract
Salinity-induced nutritional imbalances due to irrigation with brackish water could adversely affect crop production. This study evaluated the concentrations and distributions of 14 ions in roots, stems, leaves, and fruits of tomato irrigated with brackish water. The five saline treatments were tap-water of EC 0.6, brackish water of EC 2 and 3, and reverse osmosis (RO) concentrate of EC 4 and 6 dS/m. The higher concentrations of Na, Mg, Ca, K, and Cl in soil and irrigation water increased Na and Mg but decreased K and Ca concentrations in plant organs. The accumulations of micronutrients (Fe, Mn, Cu, B, and Al) except Zn in the whole plant decreased with increasing salinity levels. However, the amounts of Mn, Fe, B, and Al were positively correlated to yield at a significant level. The Principal Component Analysis (PCA) identified two PCs that explained more than 70% of variability for the whole plant, PC 1 included most ions of Na, K, Ca, P, N, Mn, Cu, Fe, B, and Al, while PC 2 included ions of Mg, Cl, S, and Zn. These results were in accord with the results of Pearson correlation analysis that tomato yield was significantly correlated to accumulations of Na, Ca, P, N, Mn, Fe, B, and Al in whole plants except K and Cu. To achieve an optimal comprehensive fruit nutrition, tomato can be irrigated up to an irrigation water salinity level of ≤2 dS/m.