Technical ArticleEffects of Combined Phosphorus-Zinc Fertilization on Grain Zinc Nutritional Quality of Wheat Grown on Potentially Zinc-Deficient Calcareous SoilLu, Xinchun; Tian, Xiaohong; Cui, Juan; Zhao, Aiqing; Yang, Xiwen; Mai, WenxuanAuthor Information Northwest A&F University, Yangling, Shaanxi Province, China. Dr. Xiaohong Tian is corresponding author. E-mail: email@example.com Received January 22, 2011. Accepted for publication August 16, 2011. Financial Disclosures/Conflicts of Interest: This study was supported by the National Natural Sciences Foundation of China (31071863, 40971179), the New-Century Excellent Talent Program of the Education Ministry of China (NCET-06-0866), and Innovative Research Team Program of Northwest A&F University in 2010. The authors have no conflicts of interest to report. Soil Science: December 2011 - Volume 176 - Issue 12 - p 684-690 doi: 10.1097/SS.0b013e3182331635 Buy Metrics Abstract A 2-year field experiment was conducted (i) to study the effect of combined P and Zn fertilization on the Zn nutritional quality of wheat grown on potentially Zn-deficient calcareous soil and (ii) to identify which soil Zn fraction had the greatest effect on grain Zn concentration. Results showed that Zn fertilization increased grain Zn concentrations by 13% in 2006–2007 and 15% in 2007–2008. However, the application of 200 kg P2O5 ha−1 combined with Zn fertilizer reduced grain Zn concentrations by 38% in 2006–2007 and 17% in 2007–2008 compared with the control (no fertilizer treatment). The phytic acid (PA) concentration and the PA:Zn molar ratio in wheat grain increased as P fertilizer application rate increased, regardless of the Zn fertilizer application rate. Zinc fertilization alone increased diethyltriaminepentaacetic acid–Zn by 220% in 2006–2007 and 470% in 2007–2008 compared with the no Zn fertilizer treatment. The combined application of P and Zn also increased diethyltriaminepentaacetic acid–Zn and loose organic matter–bound Zn, but the increase became smaller as the P fertilizer application rate increased. In conclusion, P fertilizer application rates to the potentially Zn-deficient calcareous soil used in this study should be less than 100 kg P2O5 ha−1 to ensure the efficacy of the Zn fertilizer. Among the soil Zn fractions in this study, loose organic matter–bound Zn had the greatest correlation with grain Zn concentration. © 2011 Lippincott Williams & Wilkins, Inc.