Water management mitigates drought stress effects on maize leaf senescence and post-anthesis dry matter accumulation

Drought stress during the flowering stage adversely affects maize leaf senescence, dry matter accumulation, and grain yield. A field experiment was conducted during the 2022–2023 maize growing seasons at two representative sites in China’s Huang-Huai-Hai Plain, implementing three water management strategies: maintaining relative soil water content (RSWC) above 80 % (I 80 ), maintaining RSWC above 60 % (I 60 ), and non-interference (NI) under drought stress. The study investigated the mitigation effects of these strategies on drought stress during the flowering stage of two maize hybrids (LC310 and DH605) under field conditions. Changes in ear leaf green area (GLAear), post-anthesis leaf area duration (post-LAD), post-anthesis dry matter accumulation (Post-DMA), and grain yield were measured. The dynamics of GLAear after anthesis followed a logistic model, the initial senescence period (T 1 ) identified as a key factor in leaf senescence. Well-managed irrigation (I 80 ) significantly mitigated the reduction in the photosynthetic area of middle and lower leaves (8−13) after drought stress, increasing post-LAD by 38.0 % ( P＜0.05 ) compared to drought treatments (NI). Additionally, it significantly increased the photosynthetic rate of the ear leaf by 52.6 % ( P＜0.05 ) and prolonged the T 1 phase by 12.0 days ( P＜0.05 ). well-managed irrigation enhanced Post-DMA, increased stem and leaves dry matter translocation to grain yield by 31.1 % and 33.2 % ( P＜0.05 ) respectively, compared to NI treatment. Under drought stress, well-managed irrigation significantly increased the yield by 42.4 % ( P＜0.05 ). When well-managed irrigation was not guaranteed, a small amount of irrigation (I 60 ) could still increase the yield by 27.5 %. Under drought stress, well-managed irrigation improved post-LAD, prolonged T1, delayed leaf senescence, increased the translocation of dry matter to grains, and boosted grain yield. These findings provide new insights into the role of water management under drought stress from the perspectives of leaf senescence and dry matter translocation. • Drought-induced ear leaf senescence was quantified using logistic model. • Effective water management delayed the onset of senescence and increased green leaf duration. • Effective water management redirected more stem dry matter to kernels, boosting yield contribution.