摘要
采用盆栽单株种植,以采自甘肃榆中和天祝2个扩展能力不同的野生草地早熟禾(Poa pratensis)为材料,设3个氮素施肥水平(N1,5 g·m-2;N2,10 g·m-2;N3,15 g·m-2)、3个磷素(P2O5)施肥水平(P1,5 g·m-2;P2,15 g·m-2;P3,25 g·m-2),共10个处理组合,研究了氮、磷肥对草地早熟禾氮积累、分配及硝酸还原酶(NR)活性的影响,以期为草地早熟禾草坪施肥管理提供理论和实践依据。结果表明:随施氮量增加,草地早熟禾地上、地下和整株氮积累量逐渐增加;随施磷量增加,天祝草地早熟禾地上、地下和整株氮积累量先增大后减小,榆中草地早熟禾地上、整株氮积累量逐渐增加,地下氮积累量先增大后减小。随氮、磷肥施量增加,草地早熟禾地上氮分配比例逐渐增加,地下氮分配比例逐渐降低;氮利用效率逐渐降低。草地早熟禾硝酸还原酶(NR)活性随氮肥施量的增加逐渐增加,随磷肥施量的增加先增大后减小。榆中草地早熟禾氮积累量、氮利用效率高于天祝草地早熟禾。与磷肥相比,氮肥对草地早熟禾氮积累、分配和利用的影响更为明显。硝酸还原酶活性与氮肥施量极显著(天祝)或显著(榆中)正相关,氮积累量与硝酸还原酶(NR)活性极显著正相关。
To investigate the effect of nitrogen and phosphorous application on nitrogen accumulation,allocation and nitrate-reductase activity in Kentucky bluegrass(Poa pratensis),two varieties were selected under pot culture experiments.An experiment with a randomized block design was conducted to determine the effects of different phosphorous(P2O5)application rates(5,15 and 25 g·m-2)and nitrogen application rates(5,10 and 15 g·m-2)on nitrogen accumulation,allocation and nitrate-reductase activity in Kentucky bluegrass.The results showed that aboveground nitrogen accumulation,underground nitrogen accumulation and nitrogen accumulation in whole plant increased as nitrogen application rate increased.For the Kentucky bluegrass from Tianzhu county,the aboveground nitrogen accumulation,underground nitrogen accumulation and nitrogen accumulation in whole plant as phosphorous application rate increased.For the Kentucky bluegrass from Yuzhong county,the aboveground nitrogen accumulation and nitrogen accumulation in whole plant increased,whereas underground nitrogen accumulation increased firstly,and then decreased as phosphorous application rate increased.The aboveground nitrogen allocation increased as nitrogen and phosphorous application rate increased,while The underground nitrogen allocation and nitrogen use efficiency decreased as nitrogen and phosphorous application rate increased.The nitrate-reductase activity in Kentucky bluegrass increased as nitrogen application rate increased,whereas increased firstly,and then decreased as phosphorous application rate increased.The nitrogen accumulation and nitrogen use efficiency in Kentucky bluegrass from Yuzhong county was higher than that in Kentucky bluegrass from Tianzhu county.Effects of nitrogen application on nitrogen accumulation,allocation and nitrate-reductase activity was distinctly higher than that of phosphorous application.A significant positive correlation was found between nitrate-reductase activity and nitrogen application rate(P<0.01),and between nitrate-reductase activity and nitrogen accumulation(P<0.05).
作者
张浩玮
白小明
陈辉
樊敬辉
李雄亮
连亚红
孙敏
Zhang Haowei;Bai Xiaoming;Chen Hui;Fan Jinghui;Li Xiongliang;Lian Yahong;Sun Min(College of Grassland Science/MOA Key Laboratory of Grassland Ecosystem/Pratacultural Engineering Laboratory of Gansu Province,Gansu Agricultural University,Lanzhou 730070,China)
出处
《中国沙漠》
CSCD
北大核心
2019年第5期222-231,共10页
Journal of Desert Research
基金
国家自然科学基金项目(31560667)
