Integrative analysis of nutrient uptakes for 100 kg-grain production of rice and the impact factors

Objectives We investigated the uptake and influencing factors of macro- and micronutrients for producing 100 kg grain of rice, to provide a theoretical basis for scientific fertilization of rice.

Methods The literatures published since 1990 were searched by keywords of rice, nutrient uptake, N, P₂O₅, K₂O, SiO₂, CaO, MgO, S, Fe, Mn, Zn, Cu, B, Mo and Cl in China National Knowledge Infrastructure (CNKI). There were total of 127 literatures meeting the requirement and 2763 groups of data were obtained. The nutrient absorption required per unit mass of rice was calculated, and the effects of rice type, planting areas and fertilizer application rate on the nutrient uptakes of N, P₂O₅ and K₂O were analyzed.

Results The requisite amount for producing 100 kg grain of rice was N 0.63−3.29 kg, P₂O₅ 0.23−3.26 kg, K₂O 0.54−5.23 kg, SiO₂ 4.04−18.21 kg, CaO 0.23−0.71 kg, MgO 0.17−1.19 kg, S 0.11−0.82 kg, Fe 15.02−95.35 g, Mn 31.25−94.45 g, Zn 1.73−14.97 g, Cu 152.38−831.14 mg, B 409.24−1806.15 mg, Mo 79.33−334.94 mg and Cl 0.20−0.71 kg. The P₂O₅ requirement for 100 kg-grain production of indica rice was 26.0% lower, and the K₂O requirement was 5.4% higher than that for japonica rice (P<0.05). The N requirement for 100 kg-grain production of hybrid rice was 2.7% higher and the P₂O₅ requirement was 17.4% lower than that of conventional rice. The highest P₂O₅ and K₂O absorption was in the single-season rice (1.04 and 2.74 kg), and the lowest was in late rice (0.91 and 2.45 kg, respectively). The N and K₂O absorption in northeast China rice production (1.54 and 2.03 kg, respectively) were significantly lower, while the P₂O₅ absorption (1.40 kg) was significantly higher than those in other regions. The nutrient uptakes of 100 kg-grain of rice increased with the increase of fertilizer application rate.

Conclusions The average nutrient requirements per 100 kg grain production of rice are N (1.85±0.39) kg, P₂O₅ (1.00±0.45) kg, K₂O (2.66±0.73) kg, SiO₂ (11.47±4.59) kg, CaO (0.39±0.14) kg, MgO (0.50±0.28) kg, S (0.41±0.18) kg, Fe (44.66±20.38) g, Mn (67.34±18.22) g, Zn (6.09±3.45) g, Cu (447.82±201.07) mg, B (968.41±367.06) mg, Mo (196.69±70.07) mg and Cl (0.40±0.14) kg. Nutrient uptake per 100 kg grain of rice is affected by rice types, planting areas and fertilizer application rates which should be considered in the recommendation of fertilizer.