Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images

Lodging depresses the grain yield and quality of maize crop. Previous machine learning methods are used to classify crop lodging extents through visual interpretation and sensitive features extraction manually, which are cost-intensive, subjective and inefficient. The analysis on the accuracy of sub...

Full description

Bibliographic Details
Main Authors: Xin Yang, Shichen Gao, Qian Sun, Xiaohe Gu, Tianen Chen, Jingping Zhou, Yuchun Pan
Format: Article
Language:English
Published: MDPI AG 2022-07-01
Series:Agriculture
Subjects:
Online Access:https://www.mdpi.com/2077-0472/12/7/970
_version_ 1797407890354470912
author Xin Yang
Shichen Gao
Qian Sun
Xiaohe Gu
Tianen Chen
Jingping Zhou
Yuchun Pan
author_facet Xin Yang
Shichen Gao
Qian Sun
Xiaohe Gu
Tianen Chen
Jingping Zhou
Yuchun Pan
author_sort Xin Yang
collection DOAJ
description Lodging depresses the grain yield and quality of maize crop. Previous machine learning methods are used to classify crop lodging extents through visual interpretation and sensitive features extraction manually, which are cost-intensive, subjective and inefficient. The analysis on the accuracy of subdivision categories is insufficient for multi-grade crop lodging. In this study, a classification method of maize lodging extents was proposed based on deep learning algorithms and unmanned aerial vehicle (UAV) RGB and multispectral images. The characteristic variation of three lodging extents in RGB and multispectral images were analyzed. The VGG-16, Inception-V3 and ResNet-50 algorithms were trained and compared depending on classification accuracy and Kappa coefficient. The results showed that the more severe the lodging, the higher the intensity value and spectral reflectance of RGB and multispectral image. The reflectance variation in red edge band were more evident than that in visible band with different lodging extents. The classification performance using multispectral images was better than that of RGB images in various lodging extents. The test accuracies of three deep learning algorithms in non-lodging based on RGB images were high, i.e., over 90%, but the classification performance between moderate lodging and severe lodging needed to be improved. The test accuracy of ResNet-50 was 96.32% with Kappa coefficients of 0.9551 by using multispectral images, which was superior to VGG-16 and Inception-V3, and the accuracies of ResNet-50 on each lodging subdivision category all reached 96%. The ResNet-50 algorithm of deep learning combined with multispectral images can realize accurate lodging classification to promote post-stress field management and production assessment.
first_indexed 2024-03-09T03:49:18Z
format Article
id doaj.art-4071a5a371a94c6484d794fa8b2b0740
institution Directory Open Access Journal
issn 2077-0472
language English
last_indexed 2024-03-09T03:49:18Z
publishDate 2022-07-01
publisher MDPI AG
record_format Article
series Agriculture
spelling doaj.art-4071a5a371a94c6484d794fa8b2b07402023-12-03T14:29:06ZengMDPI AGAgriculture2077-04722022-07-0112797010.3390/agriculture12070970Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral ImagesXin Yang0Shichen Gao1Qian Sun2Xiaohe Gu3Tianen Chen4Jingping Zhou5Yuchun Pan6Research Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100089, ChinaSchool of Science, China University of Geosciences, Beijing 100089, ChinaResearch Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100089, ChinaResearch Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100089, ChinaNational Engineering Research Center for Information Technology in Agriculture, Beijing 100089, ChinaResearch Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100089, ChinaResearch Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100089, ChinaLodging depresses the grain yield and quality of maize crop. Previous machine learning methods are used to classify crop lodging extents through visual interpretation and sensitive features extraction manually, which are cost-intensive, subjective and inefficient. The analysis on the accuracy of subdivision categories is insufficient for multi-grade crop lodging. In this study, a classification method of maize lodging extents was proposed based on deep learning algorithms and unmanned aerial vehicle (UAV) RGB and multispectral images. The characteristic variation of three lodging extents in RGB and multispectral images were analyzed. The VGG-16, Inception-V3 and ResNet-50 algorithms were trained and compared depending on classification accuracy and Kappa coefficient. The results showed that the more severe the lodging, the higher the intensity value and spectral reflectance of RGB and multispectral image. The reflectance variation in red edge band were more evident than that in visible band with different lodging extents. The classification performance using multispectral images was better than that of RGB images in various lodging extents. The test accuracies of three deep learning algorithms in non-lodging based on RGB images were high, i.e., over 90%, but the classification performance between moderate lodging and severe lodging needed to be improved. The test accuracy of ResNet-50 was 96.32% with Kappa coefficients of 0.9551 by using multispectral images, which was superior to VGG-16 and Inception-V3, and the accuracies of ResNet-50 on each lodging subdivision category all reached 96%. The ResNet-50 algorithm of deep learning combined with multispectral images can realize accurate lodging classification to promote post-stress field management and production assessment.https://www.mdpi.com/2077-0472/12/7/970lodging classificationunmanned aerial vehicle (UAV)sensitive bandResNet algorithm
spellingShingle Xin Yang
Shichen Gao
Qian Sun
Xiaohe Gu
Tianen Chen
Jingping Zhou
Yuchun Pan
Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
Agriculture
lodging classification
unmanned aerial vehicle (UAV)
sensitive band
ResNet algorithm
title Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
title_full Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
title_fullStr Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
title_full_unstemmed Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
title_short Classification of Maize Lodging Extents Using Deep Learning Algorithms by UAV-Based RGB and Multispectral Images
title_sort classification of maize lodging extents using deep learning algorithms by uav based rgb and multispectral images
topic lodging classification
unmanned aerial vehicle (UAV)
sensitive band
ResNet algorithm
url https://www.mdpi.com/2077-0472/12/7/970
work_keys_str_mv AT xinyang classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT shichengao classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT qiansun classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT xiaohegu classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT tianenchen classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT jingpingzhou classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages
AT yuchunpan classificationofmaizelodgingextentsusingdeeplearningalgorithmsbyuavbasedrgbandmultispectralimages