2026-04-27T02:31:41Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/701052025-02-19T12:14:19Zcom_10324_1166com_10324_931com_10324_894col_10324_1338

Vélez, Sergio Barajas Tola, Enrique Rubio Cano, José Antonio Pereira Obaya, Dimas Rodríguez Pérez, José Ramón 2024-09-24T10:59:20Z 2024-09-24T10:59:20Z 2024 Agronomy, 2024, Vol. 14, Nº. 3, 634 2073-4395 https://uvadoc.uva.es/handle/10324/70105 10.3390/agronomy14030634 634 3 Agronomy 14 2073-4395 Producción Científica This study explores spectroscopy in the 350 to 2500 nm range for detecting powdery mildew (Erysiphe necator) in grapevine leaves, crucial for precision agriculture and sustainable vineyard management. In a controlled experimental vineyard setting, the spectral reflectance on leaves with varying infestation levels was measured using a FieldSpec 4 spectroradiometer during July and September. A detailed assessment was conducted following the guidelines recommended by the European and Mediterranean Plant Protection Organization (EPPO) to quantify the level of infestation; categorising leaves into five distinct grades based on the percentage of leaf surface area affected. Subsequently, spectral data were collected using a contact probe with a tungsten halogen bulb connected to the spectroradiometer, taking three measurements across different areas of each leaf. Partial Least Squares Regression (PLSR) analysis yielded coefficients of determination R2 = 0.74 and 0.71, and Root Mean Square Errors (RMSEs) of 12.1% and 12.9% for calibration and validation datasets, indicating high accuracy for early disease detection. Significant spectral differences were noted between healthy and infected leaves, especially around 450 nm and 700 nm for visible light, and 1050 nm, 1425 nm, 1650 nm, and 2250 nm for the near-infrared spectrum, likely due to tissue damage, chlorophyll degradation and water loss. Finally, the Powdery Mildew Vegetation Index (PMVI) was introduced, calculated as PMVI = (R755 − R675)/(R755 + R675), where R755 and R675 are the reflectances at 755 nm (NIR) and 675 nm (red), effectively estimating disease severity (R2 = 0.7). The study demonstrates that spectroscopy, combined with PMVI, provides a reliable, non-invasive method for managing powdery mildew and promoting healthier vineyards through precision agriculture practices. Ministerio de Ciencia, Innovación y Universidades, Centro para el Desarrollo Tecnológico y la Innovación (CDTI) - (projects 2018/879 y 2021/1168) VITICAMPO, SL - (grant id: 2021/00009/001; T132) Comisión Europea, Acciones Marie Skłodowska-Curie (MSCA), programa Horizon 2020, - (Grant 101034297) application/pdf eng MDPI info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ © 2024 The authors Atribución 4.0 Internacional Plant diseases Plantas - Enfermedades y plagas Fungi Vegetation monitoring Uvas - Análisis Vid - Enfermedades y plagas Wine and wine making - Analysis Vinos y vinificación - Microbiología Plants - Effect of stress on Plantas, Efectos del estrés sobre las Pathogenic microorganisms - Detection Microorganismos patógenos - Detección Precision farming Agricultura - Innovaciones tecnológicas Agricultural innovations Vineyards Agronomy 3102 Ingeniería Agrícola 3103 Agronomía 3108 Fitopatología 3108.05 Hongos Field-deployed spectroscopy from 350 to 2500 nm: a promising technique for early identification of powdery mildew disease (Erysiphe necator) in vineyards info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion https://www.mdpi.com/2073-4395/14/3/634 SI