18459 - Protection of Food Crops ( Corso Integrato) - Postharvest Pathology of Food Crops

Academic Year 2018/2019

  • Docente: Elena Baraldi
  • Credits: 3
  • SSD: AGR/12
  • Language: Italian
  • Teaching Mode: Traditional lectures
  • Campus: Bologna
  • Corso: Second cycle degree programme (LM) in Agricultural Sciences and Technologies (cod. 9235)

Learning outcomes

This course trains students to:

a) know the phytopathogens agents of postharvest losses in food products; b) understand the role of integrated protection in the prevention of postharvest losses; c) evaluate the effects of pathogens attacks on the quality and on the contamination, by toxic compounds, of food products.

Course contents

POSTHARVEST PATHOLOGY

GENERAL ASPECTS (Teaching units:10)

Chilling injury (teaching units:3)

importance and limits to the use of cold chain, classification of horticultural products according to their susceptibility to chilling injury, symptoms, induced structural and physiological modifications, control.

Integrated protection of plant products (Teaching units 7)

Integrated postharvest disease management of raw and semi-processed fresh products, during storage, transportation and distribution (physical, chemical and biological methods).

Physical methods

High temperatures: types of heat treatments (hot air and hot water), effects on the host and on the pathogen.

Low temperature (cooling): importance of the cold chain in the storage and distribution of raw and semi-processed fresh plant products, effects on the host and on the pathogen.

Oxygen and carbon dioxide: importance of controlled atmosphere (CA) , dynamic CA and modified atmosphere in storage and distribution of raw and processed fresh plant products, effects on the host and on the pathogen.

Ethylene scrubbing: influence of ethylene on ripening and senescence of the products, scrubbing technologies, effects on the host and on the pathogen.

Relative humidity (RH): importance and management of RH during storage and distribution, effects on the host and on the pathogen.

Ultraviolet light at low doses: management of the treatments, effects on the host and on the pathogen.

Ionizing radiation: sources, safety, limits, effects on the host and on the pathogen.

Chemical methods

Disinfectants: importance, types of disinfectants used on fresh plant products, how to apply, efficacy.

Chemical protectants: classification, hazard classes, technical limits, safety precautions, mode of application and of action, formulation types, residues, outlook of EC regulation of pesticide residues.

Biological methods

Natural susbstances: sources, activity, non target effects, application limits.

Antagonistic microrganisms (fungi, bacteria and yeasts): mode of action, compatibilty with other control methods, formulations, efficacy limits.

SPECIFIC PRODUCT DISESASES AND DISORDERS (Teaching units 16)

Each disease and disorder is described from the point of view of:

  • importance, distribution, qualitative and quantitative losses caused
  • taxonomy, symptomatology, epidemiology and control
  • influence on product processing (losses, mycotoxins, safety issues)

Pome fruits: Neofabrea, Penicillium, Botrytis, Mucor, Alternaria, superficial scald, soft scald, watercore, bitter pit. Stone fruits: Monilinia, Botrytis*, Rhizopus, Mucor*, internal breakdown (mealiness), abnormal ripening. Kiwifruit: Botrytis*, Phialophora. Grapes: Botrytis*, Aspergillus*. Strawberry: Botrytis*, Colletotricum. Tomato: Alternaria*, Colletotricum*, Botrytis* (mold count by Howard method), Pectobacterium, chilling injury. Potato: Fusarium, Pectobacterium*, greening, sweetening, sprouting.Onion: Botrytis*, Aspergillus*, Colletotricum*, Fusarium*, Pectobacterium*, Pseudomonas, sprouting. Leafy vegetables: Sclerotinia, Botrytis*, Pectobacterium*, Pseudomonas*, russet spotting, yellowing, senescence.

* Only symptoms and control

Readings/Bibliography

Postharvest pathology

Patologia postraccolta dei prodotti vegetali
di V. De Cicco - P. Bertolini - M.G. Salerno Pagg.287, Euro 35,00 (l'importo dei diritti d'autore è devoluto alla Società Italiana di Patologia vegetale - SIPaV) - Piccin Nuova Libraria S.p.A., Padova. Italy

Atlas:

Snowdon A.L. A colour atlas of postharvest diseases & disorders of fruit & vegetables. Vol. 1 & 2 . Wolfe Scientific ed. London, 1990.

Website : http://books.google.com/books?id=WK-Scwl9skYC&pg=PA184&lpg=PA184&dq=pseudomonas+fluorescens+vegetables+rot&source=bl&ots=wSGByFca5i&sig=PLTrtJYPNRoAj-NTMIliB1-Zlzk&hl=en&ei=ZoGAToTiOKXH0QXwivnBCQ&sa=X&oi=book_result&ct=result&resnum=6&ved=0CEMQ6AEwBQ#v=onepage&q=pseudomonas%20fluorescens%20vegetables%20rot&f=false

Tonini G. Atlante delle alterazioni microrganiche postraccolta (pomacee e drupacee). Bayer s.p.a, Milano,1996, Italy.

Web sites:

[http://postharvest.ucdavis.edu/PF/] Produce facts →Choose the language (English, Francais, Espanol) → fruits /vegetables species → Link to produce photo album (miglior sito web)

AAVV. Identifying and Controlling Postharvest Tomato Diseases in Florida - http://edis.ifas.ufl.edu/

AAVV Market Diseases of Apples, Pears, and Quinces. http://postharvest.tfrec.wsu.edu/market_diseases.html#breakdown

C. L. Xiao. Postharvest Diseases of Apples and Pears - A Guide to Diagnosis and Control. http://decay.tfrec.wsu.edu/

AAVV. The Commercial Storage of Fruits, Vegetables. http://www.ba.ars.usda.gov/hb66/contents.html

Teaching methods

The course will be based on lectures and laboratory exercises, with the presentation of slides . The material presented and used during the lessons will consist of PPT presentations, relevant to help students to identify the most importants diseases of fresh horticultural products, together with some small lots of products affected by rots. A technical visit to the wholesale market (Centro Agroalimentare Bologna) of plant products will be also organized. During the visit the paticipants will learn the main protection techniques, packaging and diseases of fresh products.

Assessment methods

The exams dates and modalities are reported in ALMAESAMI.

Teaching tools

PC, projector, diseased products, study visit to wholesale market.

Office hours

See the website of Elena Baraldi