85862 - Microbiology In Plant Nutrition

Learning outcomes

At the end of the course, students are able to scientifically and technically develop field interventions based on the use of microorganisms to improve soil fertility and to transfer the information acquired to operators in the agricultural sector. The profound knowledge of the microbiological processes of the rhizosphere and of the microorganism-plant interaction represents an indispensable scientific basis for the efficient management of plant nutrition in the agricultural sector.

Course contents

Part 1: MICROBIOLOGICAL ASPECTS OF NUTRITION held by Diana Di Gioia (30 hours)

• Recall of some basic concepts of general microbiology: will be managed according to the general microbiology knowledge of the student cohort.

• Activity of microorganisms in the soil and role in biogeochemical cycles: Soil as a resource to be protected; role of microorganisms in the carbon cycle in soil; degradation of complex polymers in soil (starch, hemicellulose, pectin, chitin, cellulose, lignin); humus formation; role of microorganisms in the nitrogen cycle in the biosphere (proteolysis and ammonization, ammonium assimilation, nitrification, assimilative or dissimilatory reduction of nitrate, denitrification, nitrogen fixation); sulfur cycle; phosphorus cycle.

• The rhizosphere and plant microorganism associations: The rhizosphere and the microbial communities present in it; Positive and negative associations between soil microorganisms; methods for studying microbial diversity in soil; Mycorrhizae; Actinorrhize.

• Nitrogen fixation: Free (non-symbiotic) non-photosynthesizing nitrogen-fixing bacteria; nitrogen-fixing bacteria and biocoenosis relationships; free photosynthesizing nitrogen-fixing bacteria; chemolithotrophic nitrogen-fixing bacteria; symbiotic nitrogen-fixing bacteria; nitrogenase; oxygen protection mechanisms implemented by different microorganisms.

• Bacteria that promote plant growth: Definition of PGPR and their role in soil fertility; action of PGPRs in promoting plant growth.

• The composting process: Definition of compost and usable substrates; microbial successions in the composting process; microbiological and chemical-physical parameters involved in the composting process; stability of the compost. Microbiological safety requirements for compost.

Skills acquired in module 1: Structure and function of the main soil microbial groups and role of microorganisms in the cycle of organic matter in the soil.

 

Part 2: RHIZOSPHERE-PLANT INTERACTION AND ENDOPHYTES held by Daniele Alberoni (30 0RE)

• Recall of some basic concepts of microbial biotechnology: will be managed according to the basic biotechnology knowledge of the student cohort.

• Associations and interactions between soil microorganisms: biofilms; quorum sensing: general information, chemical mediators, examples of quorum sensing in Gram-positive and Gram-negative bacteria.

• Endophytes and the seed microbiota: What endophytic microorganisms are, types of endophytic microorganisms and their function in promoting growth. Notes on endophytic fungi. Diversity, phylogeny and colonization mechanism of seed endophytes. Functionality of the seed microbiota

• Microbial inoculants: Description of the different types of microbial inoculants that can be used in agricultural and nursery production; basic techniques for their preparation and use.

• Experimental activity (to be carried out in the laboratory or greenhouse): Laboratory activity aimed at the isolation of endophytic bacteria from root nodules of legumes and characterization of their PGPR characteristics; primer design and Real Time PCR; traditional DNA sequencing techniques

• Next Generation Sequencing (NGS).

Skills acquired in part 2: Understanding of the mechanisms of microorganism-plant interaction and biochemical-molecular techniques for the characterization of microorganisms useful in agriculture.

The course (Part 1 + Part 2) also includes a visit to a company that produces microbial inoculants and/or biofertilizers.

Readings/Bibliography

V. M. Sellitto, I microrganismi utili in agricoltura. 2020 EDAGRICOLE

G.R. Dixon, E.L. Triston Editors Soil Microbiology and Sustainable Crop Production (2010) Springer

M.T. Madigan, JM Martinko, KS Bender, DH Buckley, DA Stahl BROCK Biologia dei Microrganismi Microbiologia generale. ambientale, industriale.14a Edizione,2016 Casa Editrice Pearson.

Papers provided during classes.

Teaching slides available on Virtuale.

Teaching methods

he course is based on 2 teaching units. Moreover practical activities are provided.

Theoretical teaching units. The student will acquire knowledge on microbiological aspect of plant nutrition.

Practical activities. It will refer to the recent research and applications, in addition an excursion to a company working on the field will be performed. The activities will be conducted in respect to anticovid regulations.

As concerns the teaching methods of this course unit, all students (including all the international incoming exchange students, i.e. ERASMUS) must attend Module 1, 2 online [https://www.unibo.it/it/servizi-e-opportunita/salute-e-assistenza/salute-e-sicurezza/sicurezza-e-salute-nei-luoghi-di-studio-e-tirocinio ], while Module 3 on health and safety is to be attended in class. Information about Module 3 attendance schedule is available on the website of your degree programme ("studiare"--"formazione obbligatoria su sicurezza e salute").

Assessment methods

The learning test for this course is made through a final written examination, carried out together with the module of Microbiology of Nutrition of the integrated course. The written exam is made of 24 multiple choice questions (1 point for each correct answer) and two open answer questions about the two modules of the integrated course (maximum 3 points for each correct answer). You can, on request, sustain the final exam in English.

Teaching tools

The class rooms are equipped with video and overhead projectors, PC and Wi-Fi connection. The teacher will use the slides available with the text book. The practical parts will be performed in laboratories dedicated to this activities.

Office hours

See the website of Diana Di Gioia

See the website of Daniele Alberoni