96552 - Plant Pathology and Pathometry

Learning outcomes

Upon successful completion of the course, students will be able to identify the major plant diseases, understand their origin and modes of spread, and recognize the main biotic and abiotic causal agents. Particular emphasis will be placed on the assessment of plant disease damage through the evaluation of disease incidence and severity.

Students will also acquire knowledge of the principal plant disease management strategies and technical control measures, enabling them to understand and apply the principles of Integrated Pest Management (IPM) and organic plant protection. The course aims to provide students with the skills required to predict and reduce the spread of plant diseases while safeguarding human health, the environment, and biodiversity.

Course contents

A) Prerequisites

Students enrolling in this course are expected to possess a basic knowledge of Plant Biology, Agricultural Genetics, and General Agronomy, as provided by the courses delivered during the first and second years of the Bachelor's Degree programme.

Students are therefore strongly advised to have successfully completed these courses before taking the examination in Plant Pathology and Plant Disease Assessment (Patometry).

B) Course Structure

The course is organized into four teaching units:

1. General Plant Pathology
2. Diagnosis and Plant Disease Assessment (Patometry)
3. Principles of Plant Disease Management
4. Special Plant Pathology and Disease Management

1. General Plant Pathology

Introduction

Definition of plant disease. Economic, social, and public health implications of plant diseases. Infectious and non-infectious diseases. Morphological and physiological alterations associated with plant diseases.

Symptoms

Localized and systemic symptoms; specific and non-specific symptoms; internal and external symptoms. Main symptom categories: discoloration, morphological alterations, necrosis, wilting, hyperplasia, and hypertrophy.

Classification of Plant Diseases

Etiological classification: diseases caused by biotic or abiotic factors. Pathophysiological classification: epiphytic, trophic, necrotic, auxonic, vascular, lytic, and hypnocheuretic diseases.

Pathogenesis

The infection cycle of a fungal pathogen as a model: inoculation, spore germination, penetration, colonization, symptom development, pathogen emergence, dissemination, and survival. Monocyclic and polycyclic diseases. Concepts of endemic and epidemic diseases.

Plant Pathogens

General morphological, biochemical, and biological characteristics of fungi, oomycetes, bacteria, phytoplasmas, and viruses. Biotrophic and necrotrophic pathogens.

Phytosanitary Surveillance

Objectives of phytosanitary surveillance. Quarantine and regulated pests. Measures for preventing and limiting pathogen spread. International organizations involved in plant health and biodiversity protection, including the International Plant Protection Convention (IPPC), the European and Mediterranean Plant Protection Organization (EPPO), and the Italian National Plant Protection Service. Phytosanitary certificates for the movement of plants and plant products. The concept of phytosanitary barriers.

Host–Pathogen Interactions

Non-host resistance, host incompatibility (resistance), and host compatibility. Passive and active plant defence mechanisms.

2. Diagnosis and Plant Disease Assessment (Patometry)

Diagnosis

Visual assessment of symptom distribution at both plant and crop levels. Collection of agronomic and climatic information. Sampling procedures. Direct observation of plant samples and observation following incubation. Koch's postulates.

Plant Disease Assessment (Patometry)

Objectives of plant disease assessment. Quantification of disease symptoms through measurements of disease incidence and disease severity. Calculation of disease severity indices for evaluating the economic impact of plant diseases. EPPO assessment methods. Examples of disease indices.

3. Principles of Plant Disease Management

General Principles

Importance of plant disease management in the context of economically sustainable agriculture, environmental protection, and the production of safe, high-quality crops. Strategies aimed at reducing disease severity through interventions targeting the pathogen, the host plant, and the environment. Fundamental principles of Integrated Pest Management (IPM). Mandatory and voluntary Integrated Pest Management programmes.

Supporting Disease Management Practices

Crop rotation, Fertilization practices, Irrigation management, Selection of suitable crops and growing environments. Planting density and spacing. Soil management and crop management practices.

Other disease management approaches: thermotherapy, soil biofumigation.

Plant Protection Products

Definition of plant protection products. Statistical overview of the use of plant protection products in Italy and the European Union. Overview of the main European legislation governing plant protection products, including Regulation (EC) No. 1107/2009 and Directive 2009/128/EC. Overview of the Classification, Labelling and Packaging (CLP) Regulation (EC) No. 1272/2008. Interpretation of commercial product labels.

General Characteristics of Fungicides

Protectant and penetrating fungicides (locally systemic, translaminar, and systemic). Preventive, curative, and eradicant fungicides. Introduction to fungicide resistance in plant pathogens.

Synthetic and Naturally Derived Fungicides

Main fungicide groups. Spectrum of activity. Modes of action. Synthetic inorganic and organic fungicides Plant-derived compounds. Antagonistic microorganisms used in biological disease control.

Disease Management Strategies for Different Groups of Plant Pathogens

Overview of disease management approaches for: fungi, oomycetes, bacteria, phytoplasmas, viruses.

4. Special Plant Pathology and Disease Management

The course includes selected examples of economically important plant diseases. For each disease, the following aspects will be discussed: economic importance, geographical distribution, symptoms, epidemiology, principal disease management strategies. Diseases included: Grapevine downy mildew (Plasmopara viticola), Apple scab (Venturia inaequalis), Wheat rust diseases, Olive Quick Decline Syndrome (OQDS) (Xylella fastidiosa), Grapevine Flavescence dorée.

Supporting Learning Activities

Classroom Activities: specialist seminars on crop damage caused by adverse weather events and methods for damage assessment.

Laboratory Activities: Identification of plant disease symptoms, plant pathogenic fungi, and their reproductive structures using light microscopy.

Readings/Bibliography

Teaching materials presented during lectures will be made available on the University's VIRTUALE e-learning platform. Materials will be uploaded upon completion of each topic covered during the course. Materials presented during specialist seminars, which form an integral part of the examination syllabus, will also be made available. Students are also encouraged to consult the following textbooks:

• Vannacci G. et al. (2021). Patologia vegetale. Edises. ISBN: 8836230415.
• Belli G. (2012). Elementi di Patologia Vegetale. Piccin Editore. ISBN: 8829921297.

Teaching methods

The course combines lectures, laboratory practicals, and specialist seminars.

Lectures

Lectures are designed to provide students with the theoretical knowledge necessary to understand:

• the general characteristics of fungal, bacterial, and viral pathogens affecting agricultural, ornamental, and forest crops, together with the diseases they cause;
• the fundamental principles of Integrated Pest Management (IPM) and organic plant protection in accordance with current European legislation;
• the principles and methods of plant disease assessment (patometry);
• the major abiotic disorders affecting cultivated plants.

Students' understanding and acquisition of knowledge will be continuously monitored throughout the course by means of active interaction between the lecturer and students, with the aim of fostering critical thinking, analytical skills, and effective scientific communication.

Laboratory Practicals

Laboratory sessions provide students with practical experience in:

• observing and assessing disease symptoms on plant samples;
• applying routine laboratory techniques used in plant pathology and plant protection laboratories;
• developing practical skills that complement the theoretical knowledge acquired during lectures;
• consulting databases and specialized websites for planning disease management strategies and for understanding the appropriate use of plant protection products.

Specialist Seminars

Specialist seminars delivered by experts from academia and industry provide in-depth coverage of topics introduced during lectures and expose students to current issues and professional applications in plant pathology.

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Considering the teaching methods adopted, all students are required to complete Modules 1, 2, and 3 through the University's e-learning platform. Information regarding the schedule and attendance requirements for Module 3 is available on the Degree Programme website.

Assessment methods

Students' knowledge and competences will be assessed by means of an oral examination consisting of three questions. The examination is intended to evaluate not only the student's knowledge and understanding of the course contents, but also their critical thinking skills, ability to integrate concepts, and proficiency in using appropriate scientific terminology. Registration through AlmaEsami is mandatory. The examination registration list opens 7–10 days before the examination date and closes two days before the examination. The course, teaching materials, and oral examination will be conducted in Italian.

Students with Specific Learning Disorders (SLD) or temporary or permanent disabilities are encouraged to contact the University's competent support office well in advance. The office will propose any appropriate accommodations, which must be submitted to the course instructor at least 15 days before the examination for approval, taking into account the intended learning outcomes of the course.

Teaching tools

Lectures are delivered using computer-based presentations and multimedia projection equipment.

Laboratory practicals are carried out in the teaching laboratories (Biology I Teaching Laboratory, Viale Fanin 46, Building P1) and/or in the research laboratories and greenhouse facilities assigned to the course instructor within the Department.

Office hours

See the website of Marina Collina