Phytopathological biotechnology (2015/2016)

Course code
Annalisa Polverari
Academic sector
Language of instruction
Teaching is organised as follows:
Activity Credits Period Academic staff Timetable
teoria 5 I semestre Annalisa Polverari
laboratorio 1 I semestre Annalisa Polverari

Lesson timetable

Learning outcomes

Students will acquire a general picture of the main phytosanitary issues, with a basic introduction to biology and epidemiology of plant pathogens and the most important concepts of plant diagnosis and disease control.
On the other hand, he/she will acquire a deep understanding of molecular basis of plant- pathogen interactions, with special emphasis on mechaanisms of pathogenicity and virulence, plant resistance to pathogens, and inherent biotechnological applications.


General concepts on plant disease; description of the principal biotic plant pathogens (fungi, bacteria, phytoplasmas, viruses and viroids). Nutritional strategies and life cycle of plant pathogens. Symptom analysis and description.
Diagnosis of plant pathogens with traditional, molecular and serological techniques.
Basic concepts in epidemiology, plant disease management and control.
Molecular mechanisms of pathogenicity and virulence.
Phytopathogenic fungi and pseudo-fungi; general life cycle and virulence factors. Detailed life cycle for Plasmopara viticola, Erysiphe necator, Venturia inaequalis, Botrytis cinerea, Puccinia graminis.
Phytopathogenic bacteria: virulence factors, function of hrp and avr genes. Detailed life cycles for Erwinia amylovora, Pseudomonas syringae.
Phytopathogenic viruses: basic knowledge of replication, gene expression, assembly, movement of the viral particle into the infected plant. Detailed examples: Tobacco Mosaic Virus (TMV), Potato Virus Y (PVY). Viral transmission through vectors. Satellite viruses and satellite RNAs. Use of viruses as expression vectors. Basic knowledge of phytoplasmas and viroid infection process and epidemiology.

Plant-pathogen interaction and plant resistance to disease. Molecular bases of host specificity. Non-host resistance and race-specific resistance.
Plant-pathogen recognition: the elicitor-receptor model and the guard model.
Structure, function and evolution of plant resistance genes.
Signal transduction in plant resistence: reactive oxygen species, nitric oxide, salycilic acid, jasmonate and ethylene in plant defence.
Mechanisms of resistance: pathogenesis-related proteins, gene expression related to resistance. Post-transcriptional gene silencing as a resistance mechanism against viral pathogens.
Arabidopsis as a model plant: use of mutants for the identification of key components in the signal transduction cascade.
Systemic resistance responses: Systemic Acquired Resistance (SAR); Induced Systemic Resistence (ISR); Systemic Wound Response.
Biotechnological approaches to breed resistant plants:
transgenic expression of genes deriving from other plants, from other organisms and from pathogens (pathogen derived resistance).

Practical exercizes
Symptom observation. Isolation of fungal and bacterial pathogens in pure culture.
Morphological identification of some phytopathogenic fungi at the light microscope.
Pathogenicity test for bacteria (hypersensitive reaction on tobacco plants)
Inoculation of viral pathogens on indicator plant species.
Serological tests for identification of phytopathogenic viruses: the ELISA test.
Molecular detection of plant pathogens (PCR).

Assessment methods and criteria

Oral exam