Valeriano Germán Méndez Fuentes

Prof. Dr. Valeriano Germán Méndez Fuentes

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 December 2019 in Agronomy
Verified
Journal Article
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VFValeriano Germán Méndez Fuentes
Valeriano Germán Méndez Fuentes
APAntonio Pérez-Romero
Antonio Pérez-Romero
Rafael R. Sola-GuiradoRafael R. Sola-Guirado
Rafael R. Sola-Guirado
AMAntonio Miranda-Fuentes
Antonio Miranda-Fuentes
Francisco Manzano-AgugliaroFrancisco Manzano-Agugliaro
Francisco Manzano-Agugliaro
Antonio Rodríguez-LizanaAntonio Rodríguez-Lizana
Antonio Rodríguez-Lizana
The estimation of fruit load of an orchard prior to harvest is useful for planning harvest logistics and trading decisions. The manual fruit counting and the determination of the harvesting capacity of the field results are expensive and time-consuming. The automatic counting of fruits and their geometry characterization with 3D LiDAR models can be an interesting alternative. Field research has been conducted in the province of Cordoba (Southern Spain) on 24 ‘Salustiana’ variety orange trees—Citrus sinensis (L.) Osbeck—(12 were pruned and 12 unpruned). Harvest size and the number of each fruit were registered. Likewise, the unitary weight of the fruits and their diameter were determined (N = 160). The orange trees were also modelled with 3D LiDAR with colour capture for their subsequent segmentation and fruit detection by using a K-means algorithm. In the case of pruned trees, a significant regression was obtained between the real and modelled fruit number (R2 = 0.63, p = 0.01). The opposite case occurred in the unpruned ones (p = 0.18) due to a leaf occlusion problem. The mean diameters proportioned by the algorithm (72.15 ± 22.62 mm) did not present significant differences (p = 0.35) with the ones measured on fruits (72.68 ± 5.728 mm). Even though the use of 3D LiDAR scans is time-consuming, the harvest size estimation obtained in this research is very accurate.

13 May 2026 in Agriculture
Verified
Journal Article
Open access
PDF file
VFValeriano Germán Méndez Fuentes
Valeriano Germán Méndez Fuentes
LLLourdes Lleó
Lourdes Lleó
PBPilar Barreiro
Pilar Barreiro
ATAbraham Tamargo-Vinces
Abraham Tamargo-Vinces
WNWilson Valente Da Costa Neto
Wilson Valente Da Costa Neto
PBPilar Baeza
Pilar Baeza
This study addresses the challenge of detecting white grape bunches (Vitis vinifera L.) in high-density vineyard canopies, a critical task for precision viticulture and yield estimation. Traditional statistical and image-processing methods have struggled to cope with occlusion issues. In this work, more than 200 field RGB images were collected at La Bergonza (Toledo, Spain) and expanded through data augmentation. Several preprocessing strategies were evaluated to enhance bunch visibility. Different convolutional neural network (CNN) architectures were compared, with YOLOv8 outperforming Mask R-CNN in terms of both accuracy and efficiency. YOLOv8, trained for up to 100 epochs on equalized and augmented datasets, achieved outstanding performance, with 84.9% precision, 72.6% recall, and an mAP@0.5 of 83%, far surpassing Mask R-CNN (17% precision and 26% recall). The model successfully detected partially occluded grape bunches, including some that were not visible to human experts, and outperformed previous studies that relied on controlled backgrounds or artificial lighting. The results demonstrate that combining RGB equalization with data augmentation significantly improves detection performance. These findings highlight the potential of deep learning and low-cost RGB imaging systems to enable automated and scalable solutions for yield estimation and canopy analysis. In conclusion, YOLOv8 emerges as a promising tool for accurate grape bunch detection under real field conditions, effectively overcoming previous technological limitations.

27 March 2026 in Preprints.org
Verified
Preprint
Open access
PDF file
VFValeriano Germán Méndez Fuentes
Valeriano Germán Méndez Fuentes
LLLourdes Lleó
Lourdes Lleó
PBPilar Barreiro
Pilar Barreiro
ATAbraham Tamargo-Vinces
Abraham Tamargo-Vinces
WNWilson Valente Da Costa Neto
Wilson Valente Da Costa Neto
PBPilar Baeza
Pilar Baeza
This study addresses the challenge of detecting white grape clusters (Vitis vinifera L) in high-density vineyard canopies, a critical task for precision viticulture and yield estimation. Traditional statistical and image-processing methods have struggled with occlusion issues. In this work, over 100 field RGB images were collected at La Bergonza (Toledo, Spain) and expanded through data augmentation, with various preprocessing strategies tested to enhance cluster visibility. Convolutional Neural Network (CNN) architectures were compared, highlighting YOLOv8 as superior to Mask R-CNN in both accuracy and efficiency. YOLOv8, trained for up to 100 epochs on equalized and augmented datasets, achieved outstanding performance: 84.9% precision, 72.6% recall, and mAP@0.5 of 83%, far surpassing Mask R-CNN (17% precision, 26% recall). The model successfully detected partially hidden clusters, including those invisible to human experts, better than previous studies that required controlled backgrounds or artificial lighting. Results confirm that combining RGB equalization with data augmentation optimizes detection. These findings underscore the potential of deep learning and low-cost RGB imaging systems to enable automated, scalable solutions for yield estimation and canopy analysis. In conclusion, YOLOv8 emerges as a promising tool for accurate grape bunch detection under field conditions, overcoming previous limitations.