Optimizing Soil and Fertilizer Phosphorus Management According to the Yield Response and Phosphorus Use Efficiency of Sugarcane in Southern China

• DOI: 10.1007/s42729-020-00236-8
• Publication Date: 2020-04-02T13:32:32Z
• Authors: Qihua Wu; Wenling Zhou; Diwen Chen; Andong Cai; Junhua Ao; Zhenrui Huang
• Keywords: Soil test

The objective of this study was to determine the suitable range of available phosphorus (P) and fertilizer application rate in a sugarcane-growing region with red soil in southern China. Thirty-five monitoring sites were selected to investigate the soil available P in relation to crop yield, P-use efficiency (PUE) and soil total P under four different P rates. Compared with the no-P treatment, all three treatments involving fertilizer P presented sugarcane yields increased to varying extents, with an average increase of 17.6–25.8%. The yield-increasing effects and PUE in each P treatment decreased with increasing soil available P. The agronomic critical values of available P for sugarcane according to the linear-linear, linear-plateau and Mitscherlich models were 27.7, 41.5 and 17.0 mg kg−1, respectively. When the response of the yield-increasing effects of P fertilizer to soil available P and the agronomic critical values of the three models were combined, the linear-linear model exhibited the best fit. An observable change occurred in the available P response to total P. After the change point, the available P increased dramatically with increasing total P, possibly leading to decreased PUE or even triggering water pollution. Therefore, 28–50 mg kg−1 is the suggested range of suitable soil available P for the sugarcane-growing region. In addition, when the soil P budget and current relatively high level of available P are considered, applications of P fertilizer at 120 kg P2O5 ha−1 (1/2 the conventional P fertilizer rate) are recommended in this region.