Fertilization as the most critical factor affecting yield response and agronomic efficiency of phosphorus in Chinese rice production: evidence from multi-location field trials

BACKGROUNDEfficient utilization of phosphorus (P) has been a major challenge for sustainable agriculture. However, the responses of fertilizer rate, region, soil properties, cropping systems and genotypes to P have not been investigated comprehensively and systematically. RESULTSA comprehensive analysis of 9863 fertilizer-P experiments on rice cultivation in China showed that rice yield increased first and then fell down with the addition of P fertilizer, and the highest yield of 7963 kg ha(-1) was observed under 100% P treatment. Under 100% P treatment, the yield response of applied P (YRP) and agronomic efficiency of applied P (AE(P)) were 12.8% and 30.1 kg ha(-1), respectively. Lower soil pH (< 5.5) and organic matter (< 30.0 g kg(-1)) were associated with lower YRP and AE(P). By contrast, soil available P < 25.0 mg kg(-1) resulted in decreased YRP (15.3 to 11.4%) and AE(P) (32.3 kg kg(-1) to 26.2 kg kg(-1)), whereas soil available P > 25.0 mg kg(-1) maintained the relatively stable YRP and AE(P). Also, the YRP and AE(P) were significantly higher for single-cropping rice compared to other cropping systems. Moreover, the rice genotypes such as 'Longdun', 'Kendao' and 'Jigeng' had higher YRP and AE(P) than the average value. Overall, the fertilizer-P rate was the primary factor affecting YRP and AE(P), and the recommended P fertilizer rate can be reduced by 9-21 kg P ha(-1) compared to existing expert recommendations. CONCLUSIONThe present study highlights the role of fertilizer-P rate in maximizing the YRP and AE(P), thereby providing a strong basis for future fertilizer management in rice cultivation systems. & COPY; 2023 Society of Chemical Industry.