The Influence of Zeolite Amendment on Yield Performance, Quality Characteristics, and Nitrogen Use Efficiency of Paddy Rice

The yield and environmental benefits of zeolite (Z) applied to agriculture are clear in many different types of soil for upland crops. However, limited information is available for lowland rice (Oryza sativa L.) production systems. A 2-yr field experiment using a strip-plot design was conducted to evaluate the impact of Z amendment on yield performance, quality characteristics, and nitrogen (N) use efficiency of paddy rice. Japonica rice (cv. Gangyu 6) was cultivated in a silty loam soil with N application (0, 52.5, 105.0, and 157.5 kg N ha(-1)) as whole plots and Z amendment (0, 5, 10, and 15 t Z ha(-1)) as strip plots. Compared with the paddy field without Z amendment, there was 14.2 to 35.8% higher potential postharvest residual soil mineral N and 20.1 to 44.6% higher exchangeable potassium when the upper 30 cm of the soil was amended with 5 to 15 t Z ha(-1). Application of 5 to 15 t Z ha(-1) increased applied N fertilizer use efficiency by 39.0 to 64.4% and N recovery efficiency by 20.7 to 85.2%, respectively. Milling, appearance, and eating quality traits were not affected by Z amendment, whereas rice protein content was increased by Z addition. The enhanced yield performance due to Z was mainly caused by improved essential plant-available nutrients, which reduced ineffective tillers and produced more effective tiller number per square meter at harvest. In addition, these positive residual activities were maintained for at least an additional year after initial application in the lowland rice production system.