Differential Responses of Maize Hybrids for Growth and Nitrogen Utilization to Applied Nitrogen

The present study investigated the effects of nitrogen (N) application on the maize cultivars Xianyu 508 (XY 508) and Zhenghong 311 (ZH 311) at two experimental sites for a three-year field study.Six N levels applied were 0, 90, 180, 270, 360 and 450 kg N ha -1 .ZH 311 had comparatively greater plant height, leaf area index (LAI), dry matter and N accumulation, N partial factor efficiency, recovery efficiency, uptake efficiency and agronomic efficiency.However, it had relatively lower N grain production efficiency, harvest index (HI) and N harvest index (NHI).The response of these variables to increasing N levels was greater in XY 508 than ZH 311.In contrast, yield and its components were higher in ZH 311 than XY 508.The optimal N levels required for maximum dry matter accumulation, N accumulation and yield were greater in XY 508 (450.00,453.73 and 450.00 kg N ha -1 ) than in ZH 311 (330.14, 331.37 and 297.57kg N ha -1 ).Maize cultivar XY 508 was sensitive to low N levels should be planted in fertile plain regions or receive adequate N fertilization to ensure higher yield.On the other land, maize cultivars like ZH 311 which tolerate low N levels could be sown on barren hills and in mountainous regions to maintain high and stable yields while reducing N fertilizer application.