Effect of increasing N, P and K uptake and yield of spring maize through combined silicon and phosphate fertilizer application in Sichuan

ObjectivesThe effect of combined application of phosphorous fertilizer and silicon fertilizer on the N, P and K uptake and grain yield of spring maize was investigated on the low phosphorus brown purple soil in Sichuan Province in 2014 and 2015, in order to provide support for using silicon fertilizer to improve the efficiencies of fertilizers in this area.

MethodsA split plot field experiment was conducted continually in two years with two maize cultivars ZH2 and ZH115 as the main plots and fertilizer treatment as the subplots:neither Si nor P fertilizer, only Si fertilizer (SiO₂ 75 kg/hm²), only P fertilizer (P₂O₅ 60 kg/hm²), both P (P₂O₅, 60 kg/hm²) and Si fertilizer (SiO₂, 75 kg/hm²), named P₀Si₀, P₀Si₇₅, P₆₀Si₀ and P₆₀Si₇₅, respectively. The contents of soil available P in 0-20 and 20-40 cm soil depths were measured; The N, P and K uptake of plants in jointing stage, silking stage and harvest stage were determined, and the yield and yield components were investigated at harvest.

ResultsThere was no significant difference in N, P and K uptake of plants between the two cultivars of ZH2 and ZH115 in the two years' experiment, but the grain yield of ZH2 was significantly higher than that of ZH115 in 2014, not significant in 2015. Comparing with P₀Si₀, the N, P and K uptake in plant and grain yield were increased significantly under the treatment of P₀Si₇₅, P₆₀Si₀ and P₆₀Si₇₅, with the highest increase in P₆₀Si₇₅. In jointing and harvest stage, the N, P and K uptake in maize show significantly positive correlation with the contents of soil available P, and plant N uptake positively correlated with P and K uptake in plant. grain yield strongly positive correlated with N, P and K uptake in jointing stage and harvest stage. Compared to P₆₀Si₀ treatment, the uptake efficiency and partial factor productivity (average of 2014 and 2015) of N, P and K fertilizer were average increased 13.30% and 10.25%, 24.77% and 10.25%, 8.58% and 10.25% respectively. The grain yield was increased by 8.34% and 12.12% respectively in P₆₀Si₇₅ treatment, compared to P₆₀Si₀.

ConclusionsCombined application of Si and P fertilizer could significantly improve the P supply of soil during the whole growth stage, increase the N, P and K uptake of maize in jointing, silking and harvest stage, and increase the utilization efficiency of N, P and K fertilizers. So the technique is recommended as an effective way for increasing yield and fertilizer efficiency in the low phosphorus brown purple soil in Sichuan Province.