85862 - Microbiology In Plant Nutrition

Learning outcomes

At the end of the course, students are able to develop interventions based on the use of microorganisms to improve soil fertility and transfer the information acquired to farmers and operators of the agricultural sector. The deep knowledge of the microbiological processes of rhizosphere and the interaction between plant and microorganisms represent indispensable scientific basis for the efficient management of plant nutrition in agriculture.

Course contents

MICROBIOLOGICAL ASPECTS OF PLANT NUTRITION (40 hours)

• Activity of soil microorganisms and role in biogeochemical cycles: decomposition of complex polymers in soil; The role of microorganisms in the carbon cycle in soil; Formation of humus; Role of microorganisms in the nitrogen cycle in the biosphere (proteolysis and ammonization, ammonium assimilation, nitrification, assimilation or dissimilation of nitrate, denitrification, nitrogen fixation); Sulfur cycle; Phosphor cycle.

• Associations and interactions between soil microorganisms: positive and negative associations between soil microorganisms; biofilms; Quorum sensing.

• The rhizosphere and  plant-microorganism associations: the rhizosphere and its microbial communities; Traditional, molecular and microscopic methods to study microbial diversity in soil (with particular reference to the theoretical-practical lesson taken in the classroom); mycorrhizae; Actinorhizae.

• Nitrogen fixation: free non-symbiotic (non-photosynthetic) nitrogenous bacteria; Nitrogenous bacteria and biocenosis; Photosynthetic free nitrogenous bacteria; Nitrocellulose chemiolithotrophic bacteria; Symbiotic nitrogenous bacteria.

•  Plant growth promoting rhizobacteria: definition of PGPR and their role in soil fertility; PGPR action in promoting plant growth; Endophyte bacteria and their role in promoting plant growth.

• Compost production: microbial succession involved in compost production. Microbial safety of the final product.

SOIL MICROBIOTA (20 hours)

• Microbial inoculants: description of the different types of microbial inoculants that can be used in agricultural and plant productions.

• Colture dependent and independent technologies for the study of the soil microbiota:selection and isolation of bacterial strains, Denaturating Gradient Gel Electrophoresis (DGGE); PCR and Real Time PCR; traditional DNA sequencing and Next Generation Sequencing. 

Teaching support activity involves the organization of a visit to a company that produces microbial inoculants and participation in thematic seminars on microbial nutrition in plants.

Readings/Bibliography

It is important to study on the teaching materials used during classes (available to students) and on student notes. For more details check in:

B. Biavati, C. Sorlini, Microbiologia agroambientale, Casa Editrice Ambrosiana, Milano, 2007.

Teaching methods

1) Frontal teaching: Through frontal lectures the student will become familiar with the microbiological processes involved in the soil-plant interactions that are the basis of the fertility of the soil itself

2) Seminars and didactic visits: the student will become involved in real issues to test the skills of applying the knowledge acquired in the field of microbiology of soil and the interaction of microorganisms-soil-plant.

Assessment methods

Verification of learning will take  place through a written text, that will be performed with the course of CHEMISTRY AND BIOCHEMISTRY OF PLANT NUTRITION. The text is made of 24 multiple choice questions (1 point each) plus two open questions, one related to the Microbiology section and the other to the Chemistry and Biochemistry one (3 points each).

Students can give the exam in English asking it to the teachers at least one week befor the exam.

Teaching tools

Class teaching will be via slide projection and also a classic board. An internet connection is available in all teaching rooms.

Office hours

See the website of Diana Di Gioia