Abstract:Phosphorus (P) and zinc (Zn) are both essential elements for plant growth and development. There are strong relationships between different nutrients that changing one or more nutrients in the growth medium affects the concentrations of many other nutrients in plants. Phosphorus in the form of Pi can influence the mobility and bioavailability of many metal elements such as iron, manganese, copper, and Zn. Early studies performed in various crop species indicate the existence of a negative relationship between Pi and Zn accumulation in plants. In this study, the indica hybrid rice cultivar Guangliangyou 35 and conventional japonica rice cultivar Nipponbare were treated with combined application of three Zn levels and four P levels in field trials to investigate the effects of combinations of P and Zn on rice growth and yield production, as well as the nutrient utilization. We analyzed the shoot dry weight at different growth stages, the yield and its components at mature stage as well as the P, Zn, N and K concentrations, accumulations and distributions in different organs and tissues. Results showed that the combined application of P and Zn fertilizers had synergistic effect or antagonistic effect on the rice biomass, yield production, the nutrient absorption and distribution. Under the middle- and low P levels, the proper application of Zn increased the rice biomass and yield production. However, under the high P level, the application of Zn decreased the biomass. For different rice cultivars, under different P levels, the proper application of Zn increased the yield. The significantly increased 1000-grain weight and fertility determined the increased yield under the combined application of P and Zn fertilizers. The proper combined application of P and Zn fertilizers not only increased the concentrations of P and Zn in rice plant, but also promoted the P and Zn distribution to the productive organ. Additionally, the proper combined application of P and Zn fertilizers also increased the concentrations of nitrogen (N) and potassium (K) in rice plant, as well as the distribution of N to the productive organ, which is one of the main physiological mechanisms of increased yield production under the combined application of P and Zn fertilizers.