局部施氮对玉米生理生化特性和产量的影响

Effects of nitrogen localized supply on physiological response and yield of maize

采用大田试验,研究固定部分根区施氮、根系分区交替施氮及传统均匀施氮3种方式和高、中、低3个施氮水平对玉米叶片过氧化物酶(POD)活性、丙二醛(MDA)含量及百粒重和产量的影响。结果表明,与均匀施肥相比,固定施肥下玉米叶片的MDA含量显著增大,交替施肥明显减小。POD活性则表现为,交替施肥较之均匀施肥显著增大;固定施肥在高肥水平下明显增加,中、低肥水平下无显著差异。3种施氮方式下,MDA含量均随施氮量的增大而减小,POD活性随施氮量的增加显著增强。玉米百粒重表现为,与均匀施肥相比,交替施肥显著增大,固定施肥仅高肥水平下明显增加。两种局部施肥方式均明显提高了玉米的籽粒产量,其中,尤以交替施肥的增幅大。

By field experiment,effects of methods and quantities of N fertilization on the activity of Peroxidase（POD） and amount of malondialdehyde（MDA） in leaf during the flowering stage and yield of maize were studied.N fertilizer was supplied to two sides of maize row（conventional fertilization,CF）,or to one side only（fixed partial root zone fertilization,FPRF）,or alternatively to both sides（alternate partial root zone fertilization,APRF）.The quantities of N fertilizer included low,medium and high levels.The results showed that the amount of MDA in leaf increased significantly for FPRF treatment but decreased for APRF treatment when compared to that of CF treatment.The activity of POD was higher for APRF than for CF under all three fertilization levels.As for FPRF treatment,the activity of POD was higher under high level but there were no statistically significant differences under low and medium levels.With N fertilization increasing,the amount of MDA in leaf decreased but the activity of POD rose for all three fertilization levels.The 100-seed weight was significantly enhanced for APRF under all three fertilization levels but for FPRF only under high level when compared to that of CF treatment.Both two methods of nitrogen localized supply increased significantly maize yield when compared with that of CF and the increase for APRF was more significant.