Controlled-release nitrogen fertilizer improved lodging resistance and potassium and silicon uptake of direct-seeded rice

Authors: ZHANG, SHUGANG - Shandong Agricultural University; YANG, YUECHO - Shandong Agricultural University; ZHAI, WEWEI - Shandong Agricultural University; TONG, ZHAOCHUI - Shandong Agricultural University; SHEN, TIANLIN - Shandong Agricultural University; LI, YUNCONG - University Of Florida; ZHANG, MIN - Shandong Agricultural University; Sigua, Gilbert; CHEN, JIANQIU - Shandong Agricultural University; DING, FANGJUN - Shandong Agricultural University

Submitted to: Journal of Agronomy and Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/10/2019
Publication Date: 10/17/2019
Citation: Zhang, S., Yang, Y., Zhai, W., Tong, Z., Shen, T., Li, Y., Zhang, M., Sigua, G.C., Chen, J., Ding, F. 2019. Controlled-release nitrogen fertilizer improved lodging resistance and potassium and silicon uptake of direct-seeded rice. Journal of Agronomy and Crop Science. 59:1-8. https://doi.org/10.2135/cropsci2018.12.0765.
DOI: https://doi.org/10.2135/cropsci2018.12.0765

Interpretive Summary: Controlled-release fertilizers have been strongly advocated especially in rice production. These innovative fertilizers reduce nutrient loss while improving nutrient use efficiency, decreasing groundwater pollution and simultaneously addressing environmental and economic problems. Compared with conventional fertilizers, controlled-release fertilizers increase rice yield more with the same amount of applied nutrients due to their higher nutrient use efficiencies, while providing the same benefits of conventional fertilizers in increasing the diameter and height of rice. However, this effect has not yet tested for improving rice lodging resistance. The objective of this two-year research was to evaluate the effects of controlled-release urea (CRU) on lodging incidences, nutrient uptake, growth parameters and yield of rice. Results indicated that the lodging occurred only in urea (U) treatment. Microscopic assessment of rice stem revealed that the potassium (K) and silicon (Si) content in stems found to play important roles in rice lodging resistance. Cell image showed that plant cells from CRU treatments were tight, short, rounded and full when compared with U treatments with long, wizened and irregular cell images. These results indicated that CRU improved rice grain yield and lodging resistance due to efficient CRU’s nitrogen (N) release rate and the cumulative nitrogen (N) uptake, while also enhancing the uptake of K and Si. When compared to those of conventional urea, the N release characteristics of CRU found in this study were more closely matched the quantities of N required by direct-seeded rice over the course of its growth period. At an equivalent amount of N from urea, CRU enhanced the rice uptake of K and Si, which benefits lodging resistance. The lodging index also indicated that CRU can improve lodging resistance. The use of CRU increased mean rice grain yields by around 11.5 to 28.7 percent (%) when compared with U treatment.

Technical Abstract: Lodging, a severe problem in rice (Oryza sativa L.) production, resulted in decreased rice yield and potentially total crop loss. Controlled-release nitrogen fertilizers have found to influence rice yield, improve nitrogen (N) use efficiency, and promote the uptake of other nutrients such as phosphorus (P), potassium (K) and silicon (S). This study investigated whether a controlled-release urea (CRU) could improve lodging resistance in rice plants. In this paper, a 2-yr field experiment with four N rates (120, 180, 240, 360 kilogram (kg) N hectare (ha-1) of CRU, a conventional urea (U) fertilizer (four split applications totaling 360 kg N ha-1) and a control were evaluated in regards to yield and lodging resistance of direct-seeded rice. Results indicated that the lodging occurred only in U treatment. Microscopic assessment of rice stem revealed that the K and Si content in stems found to play important roles in rice lodging resistance. Cell image showed that plant cells from CRU treatments were tight, short, rounded and full when compared with U treatments with long, wizened and irregular cell images. These results indicated that CRU improved rice grain yield and lodging resistance due to efficient CRU’s N release rate and the cumulative N uptake, while also enhancing the uptake of K and Si.