基于无人机可见光谱平台的烤烟氮素营养诊断  

Diagnosis of Nitrogen Nutrition in Flue-Cured Tobacco Based on UAV Visible Spectrum Platform

作　　者：孙志伟 王晓琳 张启明 苑举民 张爽 闫慧峰[1] 王树声[1] SUN Zhi-wei;WANG Xiao-lin;ZHANG Qi-ming;YUAN Ju-min;ZHANG Shuang;YAN Hui-feng;WANG Shu-sheng(Tobacco Research Institute of Chinese Academy of Agricultural Sciences,Key Laboratory of Tobacco Biology and Processing,Ministry of Agriculture and Rural Affairs,Qingdao266101,China;Jiangxi Institute of Tobacco Science,Nanchang330025,China)

机构地区：[1]中国农业科学院烟草研究所/农业农村部烟草生物学与加工重点实验室,山东青岛266101 [2]江西省烟草科学研究所,江西南昌330025

出　　处：《光谱学与光谱分析》2021年第2期586-591,共6页Spectroscopy and Spectral Analysis

基　　金：国家重点研发计划项目(2018YFD0201100);中央级公益性科研院所基本科研业务费专项(1610232019004);中国烟草总公司江西省公司科技项目(2016.01.006)资助。

摘　　要：利用不同氮肥用量田间试验,分析基于无人机平台的可见光谱诊断技术对烟草氮素营养进行无损评估预测的可行性,明确该技术的最佳颜色参数和方程模型。2018年在江西省安福县开展田间试验,设置不同氮肥用量,分别为0,45,90,135,180和300 kg N·ha^-1,于移栽后47 d(团棵期)、移栽后83 d(旺长后期)和移栽后116 d(下部叶成熟期),利用无人机获取冠层RGB色彩数字图像,同时采集植株样品分析地上部生物量、叶片生物量、地上部氮浓度、叶片氮浓度、叶片SPAD值等氮营养状况指标,对冠层数字图像进行数字化分析,获得颜色指标值,通过颜色指标与烟草氮营养状况指标的相关性分析,筛选适宜的颜色指标并建立氮营养诊断方程。利用不同地块的氮肥用量试验,对氮营养诊断方程拟合精度进行验证。试验结果表明,旺长后期各处理间冠层图像的颜色标准值存在显著差异,团棵期与下部叶成熟期不存在显著差异。在10个颜色指标中,NRI,NGI,G/R,G/(R+B),(G-R)/(R+G+B)和ExG与5个烤烟氮素营养指标均达到极显著相关(p<0.01)。在归一化颜色指标体系、比颜色指标体系和归一化差分颜色指标体系中选择潜在的最佳颜色参数指标分别为NGI,G/R和ExG。根据不同类型的回归分析结果,确定指数回归作为地上部生物量和叶片生物量的预测模型,线性回归作为地上部氮浓度、叶片氮浓度及叶片SPAD值的预测模型。对潜在的最佳指标进行验证性筛选,G/R对地上部氮浓度和叶片氮浓度的RMSE值分别为0.3751%和0.2491%,明显低于NGI和ExG,预测精度最高。用G/R值表示的地上部生物量、叶片生物量、地上部氮浓度、叶片氮浓度、SPAD值预测方程分别为Y=21.785e 1.3502G/R,Y=4.0579e 1.9373G/R,Y=5.0399G/R-3.3332,Y=4.2814G/R-3.8029,Y=40.168G/R-28.188。因此,基于无人机平台的可见光谱诊断技术在烤烟氮素营养诊断方面具有应用潜力,评估最佳时期为�The feasibility of non-destructive assessment and prediction of tobacco nitrogen nutrition based on visible spectrum diagnostic technology on UAV platform was analyzed by field experiments with different nitrogen dosage,and the optimum color parameters and model of the technology were defined.Field experiments were carried out in Anfu,Jiangxi Province in 2018.Different nitrogen dosages were set at 0,45,90,135,180 and 300 kg N·ha^-1.At 47 days after transplantation(cluster stage),83 days after transplantation(flourishing late stage)and 116 days after transplantation(mature stage of lower leaves),digital images of canopy RGB color were obtained by UAV.At the same time,plant samples were collected to analyze aboveground biomass and leaf biomass.Digital analysis of canopy images was carried out to obtain the value of color indices.Through correlation analysis between color indices and tobacco nitrogen nutrition indices,appropriate color indices were screened and nitrogen nutrition diagnosis equation was established.The fitting accuracy of the diagnostic equation of nitrogen nutrition was validated by the experiment of nitrogen consumption in different plots.The results showed that the standard color values of canopy images were significantly different between different treatments in the later stage of flourishing growth,and there was no significant difference between the clustering stage and the maturity stage of lower leaves.Among the 15 color indexes,NRI,NGI,G/R,G/(R+B),(G-R)/(R+G+B)and ExG were significantly correlated with nitrogen nutrition indexes of 5 flue-cured tobacco varieties(p<0.01).According to the screening method of canopy color index,NGI,G/R and ExG are the potential optimal color parameters in the normalized color index system,the ratio color index system and the normalized difference color index system.According to different types of regression analysis results,exponential regression was determined as the prediction model of aboveground biomass and leaf biomass,and linear regression as the predicti

关 键 词：烤烟 冠层可见光谱 氮营养诊断 颜色指标 方程模型 生育期 

分 类 号：O433.4[机械工程—光学工程]