Controlled?release nitrogen fertilizer management influences grain yield in winter wheat by regulating flag leaf senescence post?anthesis and grain filling

Controlled-release nitrogen fertilizer (CRNF) is expected to meet the nutrient demands for crop growth with single application, so as achieve high-yield, high-efficiency, and labor-saving cultivation. However, under current CRNF practices, a application of in winter wheat (Triticum aestivum L.) usually fails satisfactory effects due insufficient (N) supply later stage, contributing premature leaf senescence poor grain filling. To determine reasonable strategy improving weight yield wheat, responses senescence, photosynthetic capacity, grain-filling characteristics, different types [polymer-coated urea (PCU), sulfur-coated (SCU), urea-formaldehyde (UF)] fertilization practices [single (P1) twice-split (P2)] were investigated. The results showed that, compared P1, P2 increased activities catalase, peroxidase, superoxide dismutase, alleviated accumulation malondialdehyde, delayed flag enhanced net rate (Pn) leaves, which promoted assimilate transport grains. These advantages improved process active filling duration (T), average (G), maximum (Gmax) all being higher than those significantly 1000-grain (TGW) wheat. Among three CRNFs, PCU Pn at milk-ripe stage (Zadoks GS75), dry matter post-anthesis, T, Gmax, G, contributed TGW yield. Overall, our study suggested that could substantially delay post-anthesis increase thus productivity