Laurea magistrale in Biologia dell'Ambiente

The course aims to provide students with an overview of the main associations between microorganisms and plants, and how they represent specific "microbiomes" which will be analyzed from
evolutionary, ecological, anatomical, cellular and molecular perspectives.
At the end of the course the student should have learned the concepts and methodologies to identify
i) the plant as a specialized niche of microbial communities;
ii) the symbiosis and their ecological significance and application, also in terms of biosustainability, and iii) some of the mechanisms and environmental factors that influence plant responses to beneficial and non beneficial microorganisms.

KNOWLEDGE AND UNDERSTANDING
The student should acquire knowledge on the diversity of plant-microbe
interactions in natural and altered conditions.
APPLYING KNOWLEDGE AND UNDERSTANDING
Through laboratory practicals, the student has the opportunity to observe
and directly manipulate some experimental systems
JUDGEMENT Evaluation, interpretation and revision of literature data.
COMMUNICATION SKILLS
The student presents to an audience, individually or in groups, a review
of recent scientific articles.

The written exam, with multiple choice questions and open-ended questions, refers to the part of mutualistic interactions. The oral part focuses on the interactions between plant and antagonists and between plant and the environment.

L'esame scritto, con domande a risposta multipla e domande aperte, verte sulla parte delle interazioni mutualistiche. L'orale verte sulle interazioni piante-antagonisti e piante-ambiente.

Biological interactions among living beings. Diversity and terminology of
nutritional relationships between plants and microorganisms. Definition
of symbiosis: permanent and cyclical symbioses. The symbiosis at the
origin of the eukaryotic cell.
Nitrogen-fixing symbioses. General framework and biochemical basis of
nitrogen fixation. Description of the most important nitrogen-fixing
associations. For each symbiosis, the steps leading to its formation, the
level of cell integration, the metabolic interactions and the ecological
aspects are illustrated.
- Legumes root nodules. Extraradical and intraradical stages. Molecular
signals exchanged between partners, and their perception. Nodule
organogenesis. Metabolic exchanges. Gene regulation
- Actinorhiza. Mode of infection. Comparison with the legume symbiosis.
- Plant-cyanobacteria associations. Taxonomic spectrum of the host plant.
Regulation of the symbiont differentiation.
Description of the most important associations between fungi and
photosynthetic organisms. For each symbiosis, the steps leading to its
formation, the level of cell integration, the metabolic interactions and the
ecological aspects are illustrated.
The mycorrhizal symbiosis. General characteristics and mycorrhizal
types: ectomycorrhiza and endomycorrhiza (arbuscular, orchid, ericoid)
and ectoendomicorriza. Ecological aspects of the wood-wide-web. The
contribution of sequencing projects.
The “microbiome” concept and the importance of interactions with
microbial communities: from human health to plant ecology. Modern
methods to study the taxonomic and functional diversity of bacterial and
fungal communities that interact with plants.
Interactions between plants and antagonistic organisms (predators and
pathogens).
Interactions between plants and the environment, with particular
reference to the role of the plant microbiome.
Reading, presentation and discussion of literature data.

The course material presented in class is available on the website.