Phosphorous requirement for yield formation of wheat in main wheat production regions of China

【Objectives】 Phosphorous uptake of wheat and the regional variations is the base to guild reasonable phosphorous fertilization strategy. This paper aimed to investigate the P absorption amount and the response to phosphorous fertilization in the main wheat-planting regions. 【Methods】 Data were collected from the published papers and field experiments, in which the wheat yields, P absorption in both grains and straw, P uptakes in the shoots and P concentrations in grains and straw were analyzed in the Huang-Huang-Hai winter wheat planting region (HH), Northwest China spring-winter wheat planting region (NW) and Changjiang River winter wheat planting region (CR), and the wheat P absorption under different yield levels was studied. 【Results】 The results showed that wheat grain yields, P contents in grains and straw, above-ground P uptake, P absorptions in both grains and straw and P amounts needed to produce per 100 kg grains had significant regional variations. The mean grain yield in China was 6.18 t/hm2 with a variation coefficient of 33.1%. The mean values of P concentrations in both grains and straw were 0.32% and 0.08%, and the corresponding variation coefficients were 34.3% and 75.0%. The shoot P uptake and P absorption in grains and in straw were 26.4 kg/hm2, 17.0 kg/hm2 and 5.4 kg/hm2 with the variation coefficients of 58.6%, 55.1% and 94.8%, respectively. Excluding the P concentrations in grains, all other parameters were highest in HH, and lowest in NW. The averaged P amount needed to produce 100kg grain was 0.46 kg with the variation of 37.0% in China, and HH had the highest value of 0.50 kg, while the amounts for YR and NW were 0.44 kg and 0.41, respectively. As increasing wheat yield, N requirement per 100 kg grain was increased consequently, and the N requirements were 0.41 kg, 0.43 kg, 0.50 kg, 0.52 kg for wheat yields 4.50 t/hm2, 4.50-6.50 t/hm2, 6.50-8.50 t/hm2, and 8.50 t/hm2, respectively. The P concentrations in grains maintained the certain levels with 0.32%, 0.31%, 0.31% and 0.33%, respectively for the corresponding yield levels. The P concentrations in straw increased with the corresponding values of 0.05%, 0.07%, 0.11% and 0.12% for the grain yield levels. 【Conclusions】 Differences of temperature, water and soil in the wheat-planting regions caused the differences of P absorption characteristics. For improving wheat yield and N use efficiency, wheat grain yield and P absorption for a region should be taken into account.