This article analyses the effect of the proportion of the different nitrogen forms on key enzyme activity of carbon and nitrogen metabolism under the condition of nutritional water while Tian Yan-7 was used as experim...This article analyses the effect of the proportion of the different nitrogen forms on key enzyme activity of carbon and nitrogen metabolism under the condition of nutritional water while Tian Yan-7 was used as experimental material.The result showed that nitrate reductase(NR) activity in the leaves gradually enhanced with the increase of NO - 3.No matter in root or leaves,glutamina synthetase(GS) activity first enhanced with increasing NH + 4 when NH + 4 was lower than that of NO - 3,and GS activity was the highest when NH + 4and NO - 3 was equal,then GS activity declined with NH + 4 increasing further.In the anaphase of growth,synthetic activity in root of sucrose synthetase(SS) in the mixed NH + 4 and NO - 3 was obviously highr than or NO - 3 alone.Both of the root and sugar yields were the highest when the proportion of NH + 4 and NO - 3 was 1:1.展开更多
It was shown from the experiment that glutamine synthetase activity (GSA) in both leaf blades and roots under different nitrogen levels rose rapidly to reach its peak from seedling stage to foliage rapid growth stage ...It was shown from the experiment that glutamine synthetase activity (GSA) in both leaf blades and roots under different nitrogen levels rose rapidly to reach its peak from seedling stage to foliage rapid growth stage and declined to its lowest level at the latter stage of root rapid growth, and then increased slightly. GSA in leaf blades had positive correlation with nitrogen level during the whole period of growth. GSA in roots showed the same tendency as it in leaf blades at the early middle stage of growth, but at the latter stage of growth, no positive correlation was established. GSA in leaf blades was the strongest compared with crowns, petioles and roots, and could represent the highest enzyme activity of the whole plant. GSA had quadratic curvilinear correlation with root yield and sugar production. GSA in leaf blades had significant positive correlation with α-NH2-N at the foliage rapid growth stage.展开更多
水分和氮肥是制约旱地农业生产的重要因素。基于2013—2022年内蒙古自治区突泉春玉米发育期、单产和田间管理数据,对农业生产系统模型(agricultural production system simulator,APSIM)调参验证;基于验证后的模型,结合1981—2022年突...水分和氮肥是制约旱地农业生产的重要因素。基于2013—2022年内蒙古自治区突泉春玉米发育期、单产和田间管理数据,对农业生产系统模型(agricultural production system simulator,APSIM)调参验证;基于验证后的模型,结合1981—2022年突泉气象数据,设计不同水分亏缺程度下水氮管理情景,以春玉米单产、水氮用量和效率为指标,提出春玉米最优水氮管理措施,并分析不同降水年型下春玉米适宜灌溉量和施氮量。结果表明:APSIM对春玉米出苗-开花日数、出苗-成熟日数和单产模拟值与实测值的归一化均方根误差分别为1.3%、1.2%和2.8%,APSIM可定量模拟春玉米发育期和单产。综合春玉米单产、灌溉量、施氮量、水分生产力和氮肥农学效率,最优管理措施为0~100 cm土壤剖面深度下水分亏缺程度为60%时补充灌溉,灌溉量为171.0 mm,施氮量为197.8 kg·hm^(-2)。当春玉米生长季降水量为200~400、401~600 mm和601~800 mm时,适宜的灌溉量分别为233.0~283.5、110.5~148.4 mm和125.0~155.0 mm,施氮量分别为176.9~219.3、218.3~241.5 kg·hm^(-2)和211.8~249.9 kg·hm^(-2)。展开更多
文摘This article analyses the effect of the proportion of the different nitrogen forms on key enzyme activity of carbon and nitrogen metabolism under the condition of nutritional water while Tian Yan-7 was used as experimental material.The result showed that nitrate reductase(NR) activity in the leaves gradually enhanced with the increase of NO - 3.No matter in root or leaves,glutamina synthetase(GS) activity first enhanced with increasing NH + 4 when NH + 4 was lower than that of NO - 3,and GS activity was the highest when NH + 4and NO - 3 was equal,then GS activity declined with NH + 4 increasing further.In the anaphase of growth,synthetic activity in root of sucrose synthetase(SS) in the mixed NH + 4 and NO - 3 was obviously highr than or NO - 3 alone.Both of the root and sugar yields were the highest when the proportion of NH + 4 and NO - 3 was 1:1.
文摘It was shown from the experiment that glutamine synthetase activity (GSA) in both leaf blades and roots under different nitrogen levels rose rapidly to reach its peak from seedling stage to foliage rapid growth stage and declined to its lowest level at the latter stage of root rapid growth, and then increased slightly. GSA in leaf blades had positive correlation with nitrogen level during the whole period of growth. GSA in roots showed the same tendency as it in leaf blades at the early middle stage of growth, but at the latter stage of growth, no positive correlation was established. GSA in leaf blades was the strongest compared with crowns, petioles and roots, and could represent the highest enzyme activity of the whole plant. GSA had quadratic curvilinear correlation with root yield and sugar production. GSA in leaf blades had significant positive correlation with α-NH2-N at the foliage rapid growth stage.
