Studies on plant nitrogen accumulation characteristics and the effect of single application of base fertilizer on super-high-yield summer maize.

【Objective】 The aim of the experiment is to study the fertilizer practice for realizing the target of simplify, high yield and high efficiency fertilization of super-high-yield summer maize. 【Method】 Field experiments were conducted to study the characteristics of the absorption, distribution and accumulation of N of super-high-yield summer maize (≥12 000 kg·hm-2) and the slow/controlled release nitrogen fertilizer (CRNF) application effects in 2007 and 2008. 【Result】The results showed that the stage from jointing to trumpeting and the stage from silking to the middle filling were the two critical periods for plant N absorption of maize, the plant N distribution center was leaves from seeding to silking and grain/ear after silking, respectively. N absorption proportion after silking stage was 40%-48% of the total, so it is important to provide maize with sufficient N supply at later stage not only for grain filling but also for realizing super-high-yield. The plant N accumulation, yield, N fertilizer utilization rate and N fertilizer agronomy efficiency of CRNF improved by 6%-7%, 3%-4%, 5 percentage points, and 1.26-1.59 kg·kg-1 compared with the conventional fertilizer application, respectively. 【Conclusion】 Applying CRNF was beneficial to realizing single application of base fertilizer and realizing the aim of simplify, high yield and high efficiency fertilization by increasing N absorption and accumulation in the late growing periods of super-high-yield summer maize.