Effects phosphorus application rates on dry matter translocation and nutrient uptake and utilization of winter wheat under different seeding patterns

Objectives To select the suitable application rates of P that adapted to the uniform seeding technology of winter wheat in Xinjiang, changes in dry matter, yield and nutrient efficiency of winter wheat were investigated under different application levels of P.

Methods A field experiment with two-factor complete split-plot design was conducted, using wheat cultivar Xindong 22 as tested material. The main treatment factor consisted of two seeding ways: drill seeding pattern (D) and uniform seeding pattern(U), and sub-treatment was four P₂O₅ application levels of 0, 60, 120, and 180 kg/hm², which were represented by P₀, P₆₀, P₁₂₀ and P₁₈₀ in turn. In the main growing stages, plants samples were collected for measuring dry matter distribution and transportation. At the flowering and maturity stage, plant samples were taken for measuring NPK contents. At harvest, the yield and yield components were investigated.

Results The stem diameter and plant height of winter wheat in uniform seeding pattern had significant advantages (P < 0.05) over drill seeding one. Under uniform seeding pattern and among the four P level treatments, the translocation and distribution of dry matter and the phosphorus translocation and utilization in P₁₂₀ treatment were higher than other treatments, and the yield advantage was significant (P < 0.05). The reason was that more dry matter was translocated from the vegetative organs to the seeds of the tillers, and more N, P and K were allocated into the grains and thus promoted plant phosphorus transportation and utilization. In addition, the P₁₂₀ was the best for both seeding patterns contributed to the distribution of dry matter to leaves, stems and sheaths and panicles during flowering and maturity period, thus effectively increased the dry matter transportation rate and the contribution rate of dry matter transported to the grain, thereby increased the eoonomic coefficient and achieved high yield.

Conclusions Uniform seeding is more suitable to the growth of wheat than traditional drill seeding. The appropriate application rate of phosphorus fertilizer could promote the tillering and the allocation of dry matter and NPK nutrients to the grains in tillers, thus increase the yield consequently. Under the experimental condition, the optimum P₂O₅ application rate is 120 kg/hm².