Grain Yield Formation and Nitrogen Utilization Efficiency of Different Winter Wheat Varieties under Rainfed Conditions in the Huang-Huai-Hai Plain

Winter wheat production is threatened by drought stress under rainfed conditions; thus, screening high- and stable-yielding varieties to ensure the sustainable development of food security in Huang-Huai-Hai Plain (HHHP) vital. In this research, four-year field experiments with twelve winter were conducted during wheat-growing seasons between 2016 2020 order to: (1) screen conditions, (2) investigate mechanism high-yielding yield formation relationships among grain-yield traits, (3) nitrogen utilization efficiency (NUtE) wheat. The results showed that high-yield level (HL; Yannong999, Taimai1918 Yannong173) obtained a higher average grain than medium-yield (ML) low-yield (LL) 10.1% 29.0%, respectively. Compared ML LL, HL had biomass at anthesis, spike dry matter partitioning index fruiting (grain set per unit weight anthesis), highest number square meter (24.2 × 103 m−2). Simultaneously, maintained leaf area (LAI) anthesis net photosynthesis rate (Pn) flag leaves after which contributed post-anthesis biomass; also maturity biomass, harvest (HI), remobilization comparison LL. above demonstrated improved increasing meter, remobilization, HI. Additionally, NUtE improving yield. Therefore, traits such as can help achieve high stable yields conditions.