TY - REP AU - Ping,H. AU - Bao,L. AU - Feijie,L.|Yuexian,X.|Yansheng,Y.|Naiquan,X.|Fangquan,M. AU - Jiyun,J. TI - Effect of nitrogen application rates on leaf senescence and its mechanism in spring maize (zea mays L.) SN - 7-80119-788-7 PY - 1999/// CY - Beijing (China) PB - China Agricultural Scientech Press KW - Analysis KW - Chlorophylls KW - Crop yield KW - AGROVOC KW - Maize KW - Nitrogen KW - Plant growth substances KW - Plant physiology and biochemistry KW - Zea mays ER -