胡海燕 阳会兵

摘 要：在轻简化栽培技术的前提下，研究有序机抛条件下水稻不同生育期叶绿素相对含量的光谱估算模型。分析水稻叶片SPAD 值与冠层一阶微分光谱的相关性，选取相关系数最大的波段作为敏感波长，建立了基于敏感波长的线性、指数和多项式的SPAD 值估算模型，并利用决定系数（R2）、均方根误差（RMSE）以及相对误差（RE）对模型精度进行评价。结果表明：在近红外波段（780～1000nm），杂交稻不同生育时期的光谱反射率差异较大;各生育期的SPAD值与冠层光谱相关性较好，分蘖期R439=0.7182、孕穗期R773=0.8294、齐穗期R669=0.7761和灌浆期R994=0.8028的多项式模型的SPAD值含量估测效果较好;孕穗期的模型拟合效果最佳。

关键词：有序机抛;杂交稻;SPAD值;冠层光谱

中图分类号：S511;TP7     文献标志码：A

Spectral Estimation Model for SPAD Value of Hybrid Rice under Orderly Throwing Cultivation

HU Haiyan， YANG Huibing*

（College of Agriculture， Hunan Agricultural University，

Changsha， Hunan 410128， China）

Abstract： Based on the light simplified cultivation techniques， the spectral estimation model of chlorophyll relative content of rice at different growth stages under orderly throwing cultivation was studied. The correlation between the SPAD value of rice leaves and the first-order differential spectrum of canopy was analyzed， and the band with the largest correlation coefficient was selected as the sensitive wavelength to establish the linear， exponential and polynomial SPAD value estimation model based on the sensitive wavelength， and the accuracy of the model was evaluated by using the determination coefficient （R2）， root mean square error （RMSE） and relative error （RE）. The results showed that the spectral reflectance of hybrid rice at different growth stages varied greatly in the near infrared band （780～1000 nm）; the correlation between SPAD value and canopy spectrum at each growth stage was good. The polynomial model with R439 = 0.7182 at tillering stage， R773 = 0.8294 at booting stage， R669 = 0.7761 at full heading stage and R994 = 0.8028 at filling stage had better estimation effect; the model fitting effect at booting stage was the best.

Key words： Orderly machine throwing; hybrid rice; SPAD value; canopy spectrum

水稻是我國重要的粮食作物之一，在保障国家粮食安全方面起了极其重要的作用。随着农村劳动力的减少以及现代农业的进步与发展，人们对水稻种植的机械化需求增加，而传统人工栽插的水稻种植方式已经无法适应日益发展的水稻生产需求[1]。为保证口粮安全，我国传统水稻生产方式朝机械化、轻简化的方向转型[2]。而目前机械移栽技术是水稻全程机械化生产方面的瓶颈和热点。水稻有序机抛技术作为湖南省主推的水稻栽培新技术之一，其工作效率高，且生产效益好[3]。再加上目前农业生产领域“一控两减三基本”战略中的“两减”是要求减少化肥、农药使用总量，研究有序机抛技术条件增密减肥轻简化栽培具有现实意义。……