Effects of fertilizer management strategies on maize yield and nitrogen use efficiencies under different densities

Abstract

AbstractRational plant density and fertilizer management are important practices to improve maize (Zea mays L.) yield and nutrient use efficiency. Previous research indicated that plant density and fertilization had positive interaction on maize yield and N utilization. The research studied on the interactive effects of slow‐released fertilizer (added amino acid polymer biological preparation) and density on maize yield and nitrogen use efficiencies (NUEs). A 2‐yr field experiment with varieties Suyu29 (SY29) or Suyu30 (SY30) was conducted using a split‐split plot design. Three densities (6.0, 7.5, and 9.0 × 104 plants per ha) and three fertilization modes (0F‐no fertilizer, SF‐one‐time application of slow‐released fertilizer, and CF‐twice application of conventional fertilizer) were assigned. Results indicated that grain yields and NUEs of SF under 7.5 × 104 plants per ha were the highest both in SY29 and SY30. Compared with CF under 7.5 × 104 plants per ha, SF could improve pre‐ and post‐silking N uptake and promote N translocation from stalk and leaf into grain, which increased its contribution efficiency to grain N content and obtained higher NUE. The average N partial productivity, N agronomic efficiency, N recovery efficiency, and N absorption efficiency of SF were 5.3, 9.9, 20.1, and 11.4% higher than CF under 7.5 plants × 104 plants per ha. Increasing plant density, the grain yield, total N accumulation, and NUEs initially increased and then decreased both in SF and CF. These results suggest that one‐time application of SF combined with appropriate density could increase maize yield and NUE under our experiment condition.