Reducing N Application by Increasing Plant Density Based on Evaluation of Root, Photosynthesis, N Accumulation and Yield of Wheat

(Aims) To clarify the mechanisms though which dense planting could alleviate negative effect of reducing N rate on yield, (Methods) an experiment with four nitrogen levels—0 (N0), 120 (N1), 180 (N2) and 240 (N3) kg ha−1—and three plant densities—180 (D1), (D2) 300 (D3) × 104 basic seedlings ha−1—was conducted. (Results) Increasing density decreased root length, volume, surface area tips individual while it enhanced aforementioned traits in population. The chlorophyll content, photosynthetic rate, stomatal conductance transpiration plants were increase level. increasing application leaf index, high-efficiency canopy photosynthetically active radiation accumulation per was Within same level, population, production efficiency recovery consistently D3 > D2 D1. A high not conducive to improving NR (nitrate reductase), GS (glutamine synthetase) GOGAT (glutamate synthase) activities. yield be maintained as stable or improved if decreasing by 60 ha−1 within range this experiment. (Conclusions) These results indicated that wheat less adjusting compensatory effects from populations.