Nitrogen topdressing at the jointing stage affects the nutrient accumulation and translocation in rainfed waxy maize

Abstract

Timely and fitting nitrogen (N) application decreases costs and pollution risk in maize cultivation. To explore the accumulation and remobilization of dry matter (DM), N, phosphorus (P), and potassium (K) in waxy maize under various N topdressings (0 kg ha−1, LN; 150 kg ha−1, MN; 300 kg ha−1, HN) at the jointing stage, a field trial involving two waxy maize varieties (Suyunuo 5 and Yunuo 7) was conducted in 2013–2016. The highest grain yield was obtained under MN mainly due to the highest grain numbers and grain weight. The increase in grain yield under MN was mainly due to the high DM accumulation post-silking, as well as high N, P, and K accumulation and remobilization pre-silking. Generally, the plants had high harvest index (HI) of DM (N, P, and K), partial N fertilizer productivity, and moderate N utilization efficiency (NUE) under MN.