Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices

The increasing demand for hazelnut kernels is favoring an upsurge in hazelnut cultivation worldwide, but ongoing climate change threatens this crop, affecting yield decreases and subject to uncontrolled pathogen and parasite attacks. Technical advances in precision agriculture are expected to suppor...

Full description

Saved in:
Bibliographic Details
Main Authors: Maurizio Morisio, Emanuela Noris, Chiara Pagliarani, Stefano Pavone, Amedeo Moine, José Doumet, Luca Ardito
Format: Article
Language:English
Published: MDPI AG 2025-01-01
Series:Sensors
Subjects:
Online Access:https://www.mdpi.com/1424-8220/25/1/288
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1841548919178264576
author Maurizio Morisio
Emanuela Noris
Chiara Pagliarani
Stefano Pavone
Amedeo Moine
José Doumet
Luca Ardito
author_facet Maurizio Morisio
Emanuela Noris
Chiara Pagliarani
Stefano Pavone
Amedeo Moine
José Doumet
Luca Ardito
author_sort Maurizio Morisio
collection DOAJ
description The increasing demand for hazelnut kernels is favoring an upsurge in hazelnut cultivation worldwide, but ongoing climate change threatens this crop, affecting yield decreases and subject to uncontrolled pathogen and parasite attacks. Technical advances in precision agriculture are expected to support farmers to more efficiently control the physio-pathological status of crops. Here, we report a straightforward approach to monitoring hazelnut trees in an open field, using aerial multispectral pictures taken by drones. A dataset of 4112 images, each having 2Mpixel resolution per tree and covering RGB, Red Edge, and near-infrared frequencies, was obtained from 185 hazelnut trees located in two different orchards of the Piedmont region (northern Italy). To increase accuracy, and especially to reduce false negatives, the image of each tree was divided into nine quadrants. For each quadrant, nine different vegetation indices (VIs) were computed, and in parallel, each tree quadrant was tagged as “healthy/unhealthy” by visual inspection. Three supervised binary classification algorithms were used to build models capable of predicting the status of the tree quadrant, using the VIs as predictors. Out of the nine VIs considered, only five (GNDVI, GCI, NDREI, NRI, and GI) were good predictors, while NDVI SAVI, RECI, and TCARI were not. Using them, a model accuracy of about 65%, with 13% false negatives was reached in a way that was rather independent of the algorithms, demonstrating that some VIs allow inferring the physio-pathological condition of these trees. These achievements support the use of drone-captured images for performing a rapid, non-destructive physiological characterization of hazelnut trees. This approach offers a sustainable strategy for supporting farmers in their decision-making process during agricultural practices.
format Article
id doaj-art-56e2fdb635c34c3bad4b0dda000cfa0f
institution Kabale University
issn 1424-8220
language English
publishDate 2025-01-01
publisher MDPI AG
record_format Article
series Sensors
spelling doaj-art-56e2fdb635c34c3bad4b0dda000cfa0f2025-01-10T13:21:28ZengMDPI AGSensors1424-82202025-01-0125128810.3390/s25010288Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation IndicesMaurizio Morisio0Emanuela Noris1Chiara Pagliarani2Stefano Pavone3Amedeo Moine4José Doumet5Luca Ardito6Department of Control and Computer Engineering (DAUIN), Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, ItalyInstitute for Sustainable Plant Protection, National Research Council, (IPSP-CNR), Strada delle Cacce, 73, 10135 Torino, ItalyInstitute for Sustainable Plant Protection, National Research Council, (IPSP-CNR), Strada delle Cacce, 73, 10135 Torino, ItalyDepartment of Control and Computer Engineering (DAUIN), Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, ItalyInstitute for Sustainable Plant Protection, National Research Council, (IPSP-CNR), Strada delle Cacce, 73, 10135 Torino, ItalyDepartment of Control and Computer Engineering (DAUIN), Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, ItalyDepartment of Control and Computer Engineering (DAUIN), Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, ItalyThe increasing demand for hazelnut kernels is favoring an upsurge in hazelnut cultivation worldwide, but ongoing climate change threatens this crop, affecting yield decreases and subject to uncontrolled pathogen and parasite attacks. Technical advances in precision agriculture are expected to support farmers to more efficiently control the physio-pathological status of crops. Here, we report a straightforward approach to monitoring hazelnut trees in an open field, using aerial multispectral pictures taken by drones. A dataset of 4112 images, each having 2Mpixel resolution per tree and covering RGB, Red Edge, and near-infrared frequencies, was obtained from 185 hazelnut trees located in two different orchards of the Piedmont region (northern Italy). To increase accuracy, and especially to reduce false negatives, the image of each tree was divided into nine quadrants. For each quadrant, nine different vegetation indices (VIs) were computed, and in parallel, each tree quadrant was tagged as “healthy/unhealthy” by visual inspection. Three supervised binary classification algorithms were used to build models capable of predicting the status of the tree quadrant, using the VIs as predictors. Out of the nine VIs considered, only five (GNDVI, GCI, NDREI, NRI, and GI) were good predictors, while NDVI SAVI, RECI, and TCARI were not. Using them, a model accuracy of about 65%, with 13% false negatives was reached in a way that was rather independent of the algorithms, demonstrating that some VIs allow inferring the physio-pathological condition of these trees. These achievements support the use of drone-captured images for performing a rapid, non-destructive physiological characterization of hazelnut trees. This approach offers a sustainable strategy for supporting farmers in their decision-making process during agricultural practices.https://www.mdpi.com/1424-8220/25/1/288aerial photosUAV<i>Corylus avellana</i>vegetation indicesnon-destructive analysesphenotyping
spellingShingle Maurizio Morisio
Emanuela Noris
Chiara Pagliarani
Stefano Pavone
Amedeo Moine
José Doumet
Luca Ardito
Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
Sensors
aerial photos
UAV
<i>Corylus avellana</i>
vegetation indices
non-destructive analyses
phenotyping
title Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
title_full Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
title_fullStr Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
title_full_unstemmed Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
title_short Characterization of Hazelnut Trees in Open Field Through High-Resolution UAV-Based Imagery and Vegetation Indices
title_sort characterization of hazelnut trees in open field through high resolution uav based imagery and vegetation indices
topic aerial photos
UAV
<i>Corylus avellana</i>
vegetation indices
non-destructive analyses
phenotyping
url https://www.mdpi.com/1424-8220/25/1/288
work_keys_str_mv AT mauriziomorisio characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT emanuelanoris characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT chiarapagliarani characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT stefanopavone characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT amedeomoine characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT josedoumet characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices
AT lucaardito characterizationofhazelnuttreesinopenfieldthroughhighresolutionuavbasedimageryandvegetationindices