To provide base for adjusting the sowing date,achieving the yield potential of wheat cultivars with different growth characteristics,and improving the utilization rate of natural resource in the North China Plain （NC...To provide base for adjusting the sowing date,achieving the yield potential of wheat cultivars with different growth characteristics,and improving the utilization rate of natural resource in the North China Plain （NCP）,a 4-yr field experiment of growing degree-days （GDD） before winter （realized through different sowing dates） with three wheat （Triticum aestivum L.） cultivars of each type of semi-winterness and weak springness was carried out at 20 test experimental sites （32°4’N36°1’N） of Henan Province in the NCP.The results showed that：（i） yield of semi-winterness wheat was significantly higher than weak springness wheat （P〈0.01）;（ii） there was a quadratic regression between the yield and GDD before winter.According to the regression equation,the optimum GDD range with high yield of semi-winterness and weak springness wheats was 750-770 and 570-590°C d,respectively;（iii） under the optimum GDD condition,the foliar age on the main stem of semi-winterness and weak springness wheats was 7.67-7.91 and 6.36-6.86 leaves,respectively,calculated by the linear regression equation between foliar age and GDD before winter;（iv） both semi-winterness and weak springness wheats were in the double ridge stage of spike differentiation under the condition of the optimum GDD range,and at this time,the foliar age on the main stem of semi-winterness and weak springness wheats was about 7.80 and 6.07 leaves,respectively,which was consistent with the results calculated by the liner regression equation.Therefore,we could consider that the sowing date is appropriate if the foliar age is about 7.8 and 6.3 leaves for semi-winterness and weak springness wheats,respectively.According to the results of this study,choosing semi-winterness wheat and planting 710 d earlier would improve yield and natural resource utilization in NCP.展开更多
In this note we prove the existance of (u,3,λ)IGD[v,n] and that of (w,4,λ)-IGD[v,n] where w≡1(mod 3),w≠10 or 19,and (v,n)≠(6,1),which generalizes the results of [2],[4] 3nd [5]。
【目的】基于棉花形态器官形成过程的定量描述,模拟棉花三维生长过程,为虚拟棉作研究提供技术基础。【方法】基于2005-2006年棉花品种、播期、氮素、水分和DPC化控试验,将系统分析方法和数学建模技术应用于棉花植株的形态建成,通过对棉...【目的】基于棉花形态器官形成过程的定量描述,模拟棉花三维生长过程,为虚拟棉作研究提供技术基础。【方法】基于2005-2006年棉花品种、播期、氮素、水分和DPC化控试验,将系统分析方法和数学建模技术应用于棉花植株的形态建成,通过对棉花形态数据的定量分析,构建了棉花形态建成模型,主要包括:主茎叶长宽、主茎叶柄长、主茎节间长粗、果枝叶长宽、果枝叶柄长、果节长粗以及棉铃高度和直径等模型。结合OpenGL技术,在Visual C++6.0平台上实现了棉花虚拟生长系统VGSC(virtual growth system for cotton)。【结果】棉花形态模型采用Logistic方程描述各器官尺寸随GDD(生长度日,℃·d)、氮素、水分及DPC的动态变化过程,利用2006年的试验数据对模型进行检验,棉花主茎叶长宽、主茎叶柄长、主茎节间长粗、果枝叶长宽、果枝叶柄长、果节长粗以及棉铃高度和直径的观测值与模拟值的根均方差分别为0.85、0.82、0.87、0.57、0.086、0.65、0.74、0.8、0.73、0.016、0.36和0.4cm,模型预测性好。此外,以NURBS(non-uniform rational B-spline,非均匀有理B样条)曲面模拟棉花叶片及棉铃形状,以圆柱体实现茎(节)可视化表达,构建的虚拟生长系统主要包括模型库、数据库和人机界面。【结论】用户输入系统所需的相关参数值,就可较好地模拟显示棉花器官、个体和群体的三维动态生长过程。展开更多
基金supported by the Key Technologies R&D Program of China during the 11th and 12th Five-Year Plan periods(2006BAD02A07,2011BAD16B07)
文摘To provide base for adjusting the sowing date,achieving the yield potential of wheat cultivars with different growth characteristics,and improving the utilization rate of natural resource in the North China Plain （NCP）,a 4-yr field experiment of growing degree-days （GDD） before winter （realized through different sowing dates） with three wheat （Triticum aestivum L.） cultivars of each type of semi-winterness and weak springness was carried out at 20 test experimental sites （32°4’N36°1’N） of Henan Province in the NCP.The results showed that：（i） yield of semi-winterness wheat was significantly higher than weak springness wheat （P〈0.01）;（ii） there was a quadratic regression between the yield and GDD before winter.According to the regression equation,the optimum GDD range with high yield of semi-winterness and weak springness wheats was 750-770 and 570-590°C d,respectively;（iii） under the optimum GDD condition,the foliar age on the main stem of semi-winterness and weak springness wheats was 7.67-7.91 and 6.36-6.86 leaves,respectively,calculated by the linear regression equation between foliar age and GDD before winter;（iv） both semi-winterness and weak springness wheats were in the double ridge stage of spike differentiation under the condition of the optimum GDD range,and at this time,the foliar age on the main stem of semi-winterness and weak springness wheats was about 7.80 and 6.07 leaves,respectively,which was consistent with the results calculated by the liner regression equation.Therefore,we could consider that the sowing date is appropriate if the foliar age is about 7.8 and 6.3 leaves for semi-winterness and weak springness wheats,respectively.According to the results of this study,choosing semi-winterness wheat and planting 710 d earlier would improve yield and natural resource utilization in NCP.
文摘In this note we prove the existance of (u,3,λ)IGD[v,n] and that of (w,4,λ)-IGD[v,n] where w≡1(mod 3),w≠10 or 19,and (v,n)≠(6,1),which generalizes the results of [2],[4] 3nd [5]。
文摘【目的】基于棉花形态器官形成过程的定量描述,模拟棉花三维生长过程,为虚拟棉作研究提供技术基础。【方法】基于2005-2006年棉花品种、播期、氮素、水分和DPC化控试验,将系统分析方法和数学建模技术应用于棉花植株的形态建成,通过对棉花形态数据的定量分析,构建了棉花形态建成模型,主要包括:主茎叶长宽、主茎叶柄长、主茎节间长粗、果枝叶长宽、果枝叶柄长、果节长粗以及棉铃高度和直径等模型。结合OpenGL技术,在Visual C++6.0平台上实现了棉花虚拟生长系统VGSC(virtual growth system for cotton)。【结果】棉花形态模型采用Logistic方程描述各器官尺寸随GDD(生长度日,℃·d)、氮素、水分及DPC的动态变化过程,利用2006年的试验数据对模型进行检验,棉花主茎叶长宽、主茎叶柄长、主茎节间长粗、果枝叶长宽、果枝叶柄长、果节长粗以及棉铃高度和直径的观测值与模拟值的根均方差分别为0.85、0.82、0.87、0.57、0.086、0.65、0.74、0.8、0.73、0.016、0.36和0.4cm,模型预测性好。此外,以NURBS(non-uniform rational B-spline,非均匀有理B样条)曲面模拟棉花叶片及棉铃形状,以圆柱体实现茎(节)可视化表达,构建的虚拟生长系统主要包括模型库、数据库和人机界面。【结论】用户输入系统所需的相关参数值,就可较好地模拟显示棉花器官、个体和群体的三维动态生长过程。
