Effect of Sulfur Fertilization on Productivity and Grain Zinc Yield of Rice Grown under Low and Adequate Soil Zinc Applications
Kankunlanach Khampuang, Nanthana Chaiwong, Atilla Yazıcı, Baris Demirer, İsmail Çakmak, Chanakan Prom‐u‐thai
Abstract
This study explored the responses in production and grain zinc (Zn) accumulation of rice (Oryza sativa cv. Osmancik 97) to a combination of Zn and sulfur (S) fertilization. The experiment was arranged in factorial with two Zn and three S rates of soil application in a completely randomized design with four replications. Plants were grown under greenhouse conditions at low (0.25 mg/kg) and adequate (5 mg/kg) Zn rates using a combination of S (CaSO4·2H2O) applied at low (2.5 mg/kg), moderate (10 mg/kg) and adequate (50 mg/kg) concentrations. Applying the lowest rate of S under adequate soil Zn treatment increased grain yield by 68% compared to the same S rate at low Zn supply, while plants with the adequate S rate produced the highest grain yield by 247% and 143% compared to low S rate at low Zn and adequate Zn supply, respectively. Grain Zn and S concentrations responded to the applied S rates differently depending on the soil Zn condition. The highest grain Zn concentration was 41.5 mg/kg associated with the adequate Zn supply at low S rate. Applying an adequate S at the low soil Zn conditions yielded the highest grain S concentration. The total grain Zn uptake per plant showed particular increases in grain Zn yield when applied with adequate S rates by 208% and 111% compared to low S rates in low and adequate soil Zn conditions, respectively. The results indicated that soil Zn and S application synergistically improved grain production and grain Zn yield, suggesting that attention should be given to the total grain Zn yield beside grain Zn concentration, especially under the growth conditions where grain yield shows particular increases as grain Zn is diluted due to increased grain yield by increasing S fertilization.