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作物学报 ›› 2014, Vol. 40 ›› Issue (10): 1776-1786.doi: 10.3724/SP.J.1006.2014.01776

• 耕作栽培·生理生化 • 上一篇    下一篇

基于Richards扩展方程提取水稻灌浆结实光温特性参数

杨沈斌1,2,江晓东2,王应平3,申双和1,石春林4,王萌萌2,陈斐2   

  1. 1南京信息工程大学气象灾害预报预警与评估协同创新中心 / 江苏省农业气象重点实验室,江苏南京 210044; 2南京信息工程大学应用气象学院,江苏南京 210044; 3 CSIRO Marine and Atmospheric Research, PMB # 1, Aspendale, Victoria 3195, Australia; 4江苏省农业科学院,江苏南京 210014
  • 收稿日期:2014-04-09 修回日期:2014-07-06 出版日期:2014-10-12 网络出版日期:2014-07-23
  • 基金资助:

    本研究由国家公益性行业(气象)科研专项(GYHY201306035, GYHY201306036, GYHY201206020), “十二五”国家科技支撑计划项目(2011BAD32B01)和江苏高校优势学科建设工程项目(PAPD)资助。

Charactering Light and Temperature Effects on Rice Grain Filling Using Extended Richards Equation

YANG Shen-Bin1,2,JIANG Xiao-Dong2,WANG Ying-Ping3,SHEN Shuang-He1,SHI Chun-Lin4,WANG Meng-Meng2,CHEN Fei2   

  1. 1 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters / Jiangsu Key Laboratory of Agricultural Meteorology, Nanjing University of Information Science & Technology, Nanjing 210044, China; 2 College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing 210044, China; 3 CSIRO Marine and Atmospheric Research, PMB # 1, Aspendale, Victoria 3195, Australia; 4 Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
  • Received:2014-04-09 Revised:2014-07-06 Published:2014-10-12 Published online:2014-07-23

摘要:

以籼型两系杂交稻陵两优268和两优培九为材料,进行了为期两年(20122013)的大田分期播种试验,每年分7期播种,旨在研究水稻灌浆期光温要素对籽粒灌浆结实的影响,并提取与此有关的光温特性参数。因此,以Richards方程拟合观测数据得到的平均灌浆速率为纽带,通过引入光温订正方程,建立Richards扩展方程。结合全局优化算法SCE-UA (Shuffled Complex Evolution Algorithm),优化方程参数,估算2个品种灌浆结实的光温特征参数和响应曲线。结果显示,光照主要通过影响籽粒最终重量而间接作用于平均灌浆速率,温度则通过影响灌浆进程的快慢作用于平均灌浆速率。陵两优268灌浆结实期的光照阈值(R0)、最低(Tmin)、最高(Tmax)和最适温度(Top)分别为18.94 MJ m-2 d-16.8130.2833.29; 两优培九上述参数分别为21.71 MJ m-2 d-16.1024.1633.74。形成的光照和温度响应曲线,能够较好地反映两品种平均灌浆速率对光温条件的响应差异,其中陵两优268平均灌浆速率表现为温度敏感型,而两优培九表现为光照敏感型。本文运用数学模型方法定量分析和比较了光温要素对有效灌浆期内平均灌浆速率的影响,其方法和结论为建立相应的农业气象指标,评估气候资源对水稻产量的影响提供了重要参考依据。

关键词: 水稻, 灌浆结实期, 光温环境, 数学模型, 参数优化

Abstract:

Richards equation has been widely used to simulate rice grain filling rates, but the lack of capability to relate environmental factors in its simulation impedes the application of Richards equation in evaluating the impact of adverse climate on grain filling process. Therefore, a mathematical modeling method, together with two-year filed-seeding experiment (2012–2013) data, was used in this paper to examine the feasibility of an extended Richards equation on this issue. The two-year experiment was carried out in Nanjing with two indica two-line hybrid rice cultivars, Lingliangyou 268 and Liangyoupeijiu. On the basis of the observations, Richards equation was first used to estimate rice grain filling parameters and calculate mean grain filling rate in each effective grain filling period. Subsequently, a radiation and temperature correction function was introduced into the Richards equation to form an extended equation by linking the mean grain filling rates to daily radiation and mean temperature observations. A set of radiation and temperature characteristic parameters were included in the correction function, which theoretically reflect the response of mean grain filling rates to the change of temperature and radiation conditions and form response curves for the two tested varieties. To estimate these parameters, we applied the Shuffled Complex Evolution (SCE-UA) global optimization algorithm in this paper, since the extended equation was highly nonlinear. Statistical methods were also applied to analyze the relations between retrieved rice grain filling parameters and climatic factors. The results showed that insufficient sun radiation had an indirect and negative effect on mean grain filling rate by imposing an adverse influence on CO2 assimilation. Daily mean temperature mainly showed an evident effect on mean grain filling rate which could be accelerated under high temperatures or slow down at adverse low temperatures, but it also had a great influence on CO2 assimilation as well as the accumulation of assimilation products in grains. The estimated critical radiation and critical temperatures for Lingliangyou 268 were 18.94 MJ m-2 d-1, 6.81°C, 30.28°C, 33.29°C, respectively, and 21.71 MJ m-2 d-1, 6.10°C, 24.16°C, and 33.74°C for Liangyoupeijiu, which demonstrate an evident difference between the two varieties. Quantitative analyses based on the temperature and radiation response curves showed that the correction coefficients for rice seeding dates in May in 2012 for both rice varieties were generally higher than that of other seeding dates, which implies that the time of seeding is critical to grain filling and yield formation. In addition, Lingliangyou 268 exhibited stronger temperature sensitivity in grain filling period, which means that the mean grain filling rate is more sensitive to the temperature change than to the radiation variation. In comparison, Liangyoupeijiu represented greater radiation sensitivity in grain filling, which indicates that this cultivar can be greatly influenced by insufficient radiation during the grain filling stage. On the whole, the mathematical model presented successfully retrieved the critical parameters representing the effects of daily mean temperature and radiation on mean grain filling rates from field observations. Although more validations are expected to examine the reliability and effectiveness of the proposed method, it can be an important reference for developing agro-meteorological indexes for monitoring and evaluating the effects of meteorological factors on rice grain filling as well as on yield formation.

Key words: Rice, Grain filling, Light-temperature, Mathematical model, Parameter optimization

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