Biomass accumulation and partition in different plant organs affect the grain yield in cereal crops. Many investigators have established equations to simulate the dynamic growth and biomass accumulation of crops in various experiments using polynomial, Expolianear, Logistic, and Richard models. However, these models have limitations in some extent. The vapor pressure (VP) model has been used to quantitatively simulate the dynamic accumulation of dry matter in maize (Zea mays L.) roots and the branch number of princess flower. In this study, the VP model was introduced in wheat (Triticum aestivum L.) to test its applicability in simulating accumulation and partitioning of biomass. Four wheat cultivars with four plant types, respectively, were planted in 2006-2007 and 2007-2008 growing seasons under the nitrogen application levels of 75,150, and 225 kg ha~(-1). Based on the dry weights of various organs at main growth stages, the Richards and VP equations tested the fitness of the biomass accumulation and partitioning in relation to accumulated growing-degree days. The results showed that with increasing nitrogen rate, the average dry matter growth rate (R_a), maximum growth rate (R_(max)) and duration of the third phase (D_3) increased, while the time reaching to R_(max) was shortened consistently in four cultivars. In Aikang 58 (compact-short type), Huaimai 17 (loose type) and Yangmai 12 (intermediate type), the initial growth potential (R_0) increased with the promotion of nitrogen rate, while the duration of early increment phase (D_1) and the dry matter accumulation at R_(max)(W_(Rmax)) decreased. In contrast, the R_0, W_(Rmax), and Ningmai 9 (compact-high type) exhibited an opposite pattern. In Aikang 58 and Ningmai 9, the second phase duration (D_2) decreased when the nitrogen rate increased, and Yangmai 12 and Huaimai 17 had the smallest D_2 value under the medium nitrogen rate. With the increase of nitrogen rate, the maximum dry matter partitioning percentage (P_(max)) of leaf and spike in Huaimai 17 and Yangmai 12 as well as the maximum dry matter partitioning percentage of stem and sheath (P_(Smax)) in Aikang 58 and Ningmai 9 decreased. In contrast, the P_(max) of leaf and spike in Aikang 58 and Ningmai 9, and the P_(Smax) in Huaimai 17 and Yangmai 12 increased accompanying with the increase of nitrogen rate. In terms of the maximum decreasing rate of dry matter partitioning percentage (MDRP) to leaf, Ningmai 9, Huaimai 17 and Yangmai 12 showed a decrease trend when nitrogen rate increased, while Aikang 58 was in an increase tendency. For the maximum increasing rate of dry matter partitioning percentage (MIRP) to spike, Aikang 58 and Ningmai 9 had a negative response to nitrogen rate and Huaimai 17 and Yangmai 12 had a positive response. Excessive application of nitrogen had negative effects on the promotion of MDRP to spike in Ningmai 9 and the reduction of MIRP to spike in Yangmai 12. No consistent effects were observed on the maximum changing rate of dry matter partitioning percentage to stem and sheath (R_(Simax) and R_(Sdmax))- Thereby, plant types of wheat cultivars should be considered in the nitrogen application regime in practical system of cultivation techniques.%为了揭示株型和施氮量对小麦干物质积累与分配动态的影响,通过实施不同株型小麦品种和氮肥处理的田间试验,于主要生育期测定了各处理单株及不同器官干物质积累量,并分别利用Richards和VP方程对其进行拟合.结果表明,适量施氮提高了各株型小麦的干物质平均增长速率(R_a)和最大增长速率(R_(max)),缩短了各株型小麦到达R_(max)的时间,延长了各株型小麦的缓增持续期(D_3).施氮提高了紧凑型矮秆品种矮抗58、松散型品种淮麦17和中间型品种扬麦12的起始生长势(R_0),缩短了上述3种株型小麦的渐增持续期(D_1),降低了其到达R_(max)时的干物质积累量(W_(Rmax)),而紧凑型高秆品种宁麦9号的R0、W_(Rmax)和D1与上述3种株型小麦的变化趋势相反.随施氮量的增加,矮抗58和宁麦9号的快增持续期(D_2)呈下降趋势,而淮麦17和扬麦12的D_2以中氮处理(150 kg hm~(-2))最低.施氮降低了淮麦17和扬麦12的叶、穗最大分配比例(P_(max))以及矮抗58和宁麦9号的茎鞘最大分配比例(P_(Smax)),但增加了矮抗58和宁麦9号的叶部和穗部P_(max)以及淮麦17和扬麦12的P_(Smax).施氮降低了宁麦9号、淮麦17和扬麦12的叶分配比例最大下降速率及矮抗58和宁麦9号的穗分配比例最大增长速率,而增加了矮抗58的叶分配比例最大下降速率及淮麦17和扬麦12的穗分配比例最大增长速率,但过量施氮抑制了宁麦9号穗分配比例最大增长速率的增加和扬麦12穗分配比例最大增长速率的下降.施氮对各株型小麦茎鞘分配比例最大增长和下降速率(R_(Simax)和R_(Sdmax))的影响无明显规律.因此,在建立高产小麦栽培技术体系时,应充分考虑到不同株型小麦干物质积累和分配动态对施氮量的响应差异.
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