不同品种和氮肥条件下水稻根系主要几何参数动态量化

目的建立基于生物量的水稻根系主要几何参数动态模型,为水稻功能-结构模型的研究奠定基础。方法于2008和2009年设置3个品种两优108(V1,杂籼)、86优8(V2,杂粳)和南粳43(V3,常规粳稻)]和2个氮肥水平盆栽试验获取根系形态及根干重等指标,采用SPSSv13.0与Excel2007处理试验数据,RMSE检验模型。结果利用2008年观测资料,通过分析不同品种与施肥处理下水稻单株总根长及根直径与生物量间的定量关系,建立了基于生物量的水稻单株总根长动态模型;根据立体几何原理,构建了基于生物量的水稻总根体积与总根表面积动态模型。经2009年独立试验资料检验,单株总根长、总根体积及总根表面积的实测值与模拟值的RMSE分别为490.660cm/plant、131.859cm2/plant和2.532cm3/plant,说明模型拟合度较好。结论所建水稻根系主要几何参数模型具有一定机理性、解释性和通用性,对水稻功能-结构模型研究及水稻可视化奠定了基础。

Quantitative Research of Dynamic Models of the Main Geometric Parameters of Rice Root System of Different Varieties Under Different Nitrogen Conditions

【Objective】 The aims of this study were to build the biomass-based main geometric parameter dynamic models of rice root system according to the relationships between the total root length, the total root volume, the total root surface area per plant and the dry weight per plant of different rice cultivars under different fertilizer levels. 【Method】 Three rice cultivars, ‘Liangyou108’ (Hybrid long-shaped rice, V1), ‘86you8’ (Hybrid round-shaped rice, V2), and ‘Nanjing43’ (Round-shaped rice,V3), were planted in pots with two fertilizer levels: fertilizer (N:3.6 g/pot, P2O5:0.8 g/pot, K2O:3.6 g/pot) , and no fertilizer (with loamy soil) to obtain the root system morphological characteristics, the dry weight, etc., which were processed by SPSS v13.0 and Excel 2007. The models developed in this paper were verified using RMSE.【Result】The biomass-based dynamic models of the total root length were set up through analyzing relationships between the total root length and the biomass per plant from the experimental data in 2008, and then, the biomass-based dynamic models of the total root volume and the total root surface area per plant also were developed according to the principles of solid geometry, which were tested by using the experiment data in 2009. The results showed that the RMSE between the simulated values and the observed values of the total root length, the total root volume, and the total root surface area per plant were 490.660 cm/plant, 131.859 cm2/plant, and 2. 532 cm3/plant, respectively. 【Conclusion】 The models developed in this paper were reliable with mechanics, general adaptability, and interpretative characteristics in a certain extent, which would lay a basis for developing Functional-Structure Rice Models.