Post-silking leaf senescence is delayed in low-N-tolerant maize cultivars under low N fertilization  

作　　者：Gui Wei Xinglong Wang Yawei Wu Fan Liu Tianqiong Lan Qinlin Liu Chengcheng Lyu Fanlei Kong Jichao Yuan 

机构地区：[1]College of Agronomy,Sichuan Agricultural University,Chengdu 611130,Sichuan,China [2]Key Laboratory of Crop Ecophysiology and Farming System in Southwest China,Ministry of Agriculture,Chengdu 611130,Sichuan,China [3]Crop Ecophysiology and Cultivation Key Laboratory of Sichuan Province,Chengdu 611130,Sichuan,China

出　　处：《The Crop Journal》2025年第1期246-256,共11页作物学报(英文版)

基　　金：supported by the National Key Research and Development Program of China(2022YFD190160304 and 2018YFD0301206);Natural Science Foundation of Sichuan Province(2022NSFSC0013);Sichuan Provincial Maize Innovation Team Construction Project(SCCXTD-2023-02).

摘　　要：A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.

关 键 词：Low-N-tolerant maize variety Nitrogen fertilizer Spatio-temporal characteristics Chlorophyll degradation 

分 类 号：S513[农业科学—作物学]