ABSTRACT Fomitiporia mediterranea , commonly known as ‘Esca’, is a detrimental fungus for many tree species and grapevine and is considered to be one of the main causal agents of wood decay of olive plantations in the Mediterranean region. Symptomatic trees are mainly identified at the advanced stages of the disease, so no curative control measures can be applied. In recent years, spectral measurements have been used in agriculture for early detection of disease incidents. In this paper, Linear Discriminant Analysis (LDA) of hyperspectral data collected in situ by a ASD FieldSpec® 3 spectroradiometer was used to investigate its potential for identifying alterations caused by the fungus in the most popular Greek olive cultivars ‘Amfissis’, ‘Chalkidikis’, ‘Mastoidis’, ‘Koroneiki’ and ‘Kalamon’. In order to identify the optimal wavelength ranges for LDA that are indicative of Fomitiporia mediterranea presence, Principal Component Regression (PCR) and Partial Least Square Regression (PLSR) were applied. The results showed a good classification accuracy of infected and non-infected trees. Furthermore, trees that were not identified as diseased through laboratory analysis (reisolation from trunks) but had been artificially infected at the beginning of the experiment, were actually classified as infected by LDA, implying that hyperspectral scanning was able to identify past infection even if the pathogen was no longer present.

中文翻译：

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光谱测量的线性判别分析，用于区分被 Fomitiporia mediterranea 人工感染的 Olea europaea L. 的健康和患病树木

摘要 Fomitiporia mediterranea，俗称'Esca'，是一种对许多树种和葡萄藤有害的真菌，被认为是地中海地区橄榄种植园木材腐烂的主要病原体之一。有症状的树木主要是在疾病的晚期发现的，因此无法采取治愈性控制措施。近年来，光谱测量已在农业中用于疾病事件的早期检测。在本文中，使用 ASD FieldSpec® 3 光谱仪在原位收集的高光谱数据的线性判别分析 (LDA) 用于研究其识别最流行的希腊橄榄品种“Amfissis”、“Chalkidikis”中真菌引起的改变的潜力, 'Mastoidis', 'Koroneiki' 和 'Kalamon'。为了确定 LDA 的最佳波长范围，该范围表明存在 Fomitiporia mediterranea 存在，应用了主成分回归 (PCR) 和偏最小二乘回归 (PLSR)。结果表明，受感染和未受感染的树木具有良好的分类准确率。此外，未通过实验室分析（从树干重新隔离）但在实验开始时被人为感染的树木实际上被归类为 LDA 感染，这意味着高光谱扫描能够识别过去的感染，即使病原体不再存在。结果表明，受感染和未受感染的树木具有良好的分类准确率。此外，未通过实验室分析（从树干重新隔离）但在实验开始时被人为感染的树木实际上被归类为 LDA 感染，这意味着高光谱扫描能够识别过去的感染，即使病原体不再存在。结果表明，受感染和未受感染的树木具有良好的分类准确率。此外，未通过实验室分析（从树干重新隔离）但在实验开始时被人为感染的树木实际上被归类为 LDA 感染，这意味着高光谱扫描能够识别过去的感染，即使病原体不再存在。