HORT*4300 Postharvest Physiology

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The following description is for the course offering in Winter 2023 and is subject to change. It is provided for information only. The course outline distributed to the class at the beginning of the semester describes the course content and delivery, and defines the methods and criteria to be used in establishing the final grades for the course. Offered in odd-numbered years

This course provides an examination and discussion of physiological and biochemical processes unique to postharvest development and deterioration. Principles and practices of storing fruits, vegetables, and florists' and nursery stocks as well as marketing pathways for horticultural crops will be considered.

Pre-Requisites: AGR*2470


Teaching Assistant:

Credit Weight:


Course Level:

  • Undergraduate

Academic Department (or campus):

Department of Plant Agriculture



Semester Offering:

  • Winter

Class Schedule and Location:

Please refer to WebAdvisor for class schedule and location.

Learning outcomes:

At the end of this course, students should be able to:

  1. Have a broad knowledge about fruits, vegetables and flowers and the physiological characteristics of their development into an edible or commercially usable product.
  2. Know the physiological and biochemical changes that occur after harvest, and how such changes lead to the deterioration of the produce.
  3. Understand the strategies involved in the utilization of various technologies for the preservation of shelf life and quality.
  4. Have developed critical reasoning, judgment and communication skills.
  5. Create/deliver a seminar and direct discussion on a topic related to postharvest physiology through appropriate review of literature and independent preparation of a presentation

Lecture Content:

In general, each week of the course covers a specific postharvest topic to be delivered in one to two lectures. Emphasis is placed on class discussion. Background reading will be useful for each topic.

  • Physiology/Biochemistry - Biological basis for postharvest practices, emphasizing biotic and abiotic factors (e.g., maturity, temperature, humidity, gaseous atmosphere, ethylene, gene action and regulation, etc.) which affect metabolism, senescence, stress-induced physiological disorders and quality of harvested horticultural products.
  • Postharvest Technology - Principles, application and limitation of methods and special techniques such as "common" and controlled atmosphere storage, pre-cooling, and high humidity storage; some modern instrumentation for assessing quality such as for volatile analysis, packing line technology; novel ethylene antagonists (e.g. 1-MCP), phospholipase D inhibition technology etc., to extend shelf-life of horticultural products.
Labs & Seminars:

Each laboratory period of up to 170 minutes per week may include - 1) a lab demonstration or class discussion of certain post-harvest principles not necessarily covered in lecture, 2) web searches on postharvest topics or 3) a field trip, or other suitable topic of interest.

Lab Topics will include:

  1. Analysis of firmness in fruits
  2. Analysis of colour properties of fruits and vegetables
  3. Analysis of soluble solids and/or titratable acidity
  4. Analysis of antioxidants in fruits and vegetables
  5. Shelf life extension using preservative and/or cold storage techniques

Seminars are expected to be 25-30 minutes duration with 10 minute question period. Seminar presentations carry 30% of the marks. A list of suggested topics for seminars will be posted to CourseLink; topics chosen by students can also be proposed to Dr. Bozzo.

Course Assignments and Tests:

Assignment or test Contribution to Final Mark Learning Outcomes Assessed

Midterm Exam

30% 1, 2, 3, 4
Labs/Reports 25%

1, 2, 3, 4

Seminar 30%

1, 2, 3, 4, 5

Participation 15%

1, 2, 3, 4


Final examination:

There is no final examination scheduled for this course.

Course Resources:

Recommended Texts:

Advances in postharvest management of horticultural produce (First edition) (Textbook)
Watkins, C. (editor) 2020. eBook, Imprint Burleigh Dodds Science Publishing, London, United Kingdom, 320 pp.

Available as an online book via the U of Guelph Library.

Postharvest Physiological Disorders in Fruits and Vegetables (Textbook)
Tonetto de Freitas, S., and Pareek, S. (Editors) 2008. CRC Press, Boca Raton, Florida, United States, 852 pp.

Available as an online book via the U of Guelph Library.

Postharvest Physiology and Biochemistry of Fruits and Vegetables (Textbook)
Yahia, E.M. (Editor) 2019. Woodhead Publishing (Elsevier), Duxford, United Kingdom, 476 pp.

Available as an online book via the U of Guelph Library.

Postharvest Technology of Horticultural Crops (3rd edition) (Textbook)
Kader, A.A. (editor). 2002. University of California, Agriculture and Natural Resources, Publication 3311, 535pp.

Text available at McLaughlin Library, Book Stacks; SB319.7 .P67 2002

Lab Manual:

There is no lab manual for this course. Detailed information will be provided before the labs in advance.

Other Resources:

The Commercial Storage of Fruits, Vegetables, and Florist and Nursery Stocks (Website) http://www.ba.ars.usda.gov/hb66/index.html  USDA Agricultural Handbook #66. Gross, K., C.Y. Wang, and M.E. Saltveit (editors). 2002.

Postharvest biology and technology (Article) https://www.journals.elsevier.com/postharvest-biology-and-technology/

Scientia Horticulturae (Article) https://www.journals.elsevier.com/scientia-horticulturae/

Journal of the American Society of Horticultural Science (Article) http://journal.ashspublications.org/


Course Policies:

Grading Policies:

For all assignments a penalty of minus 10% of the grade for that assignment will be deducted per late day, unless academic consideration has been granted by the instructor.

Course Policy on Group Work:

Not applicable.

Course Policy regarding use of electronic devices and recording of lectures:

Electronic recording of classes is expressly forbidden without consent of the instructor. When recordings are permitted they are solely for the use of the authorized student and may not be reproduced, or transmitted to others, without the express written consent of the instructor.

The materials provided in this course are the property of the course instructors unless otherwise stated, including tests and exams. Third party copyrighted materials (such as book chapters and articles) have either been licensed for use in this course, or have been copied under an exception or limitation in Canadian Copyright law. The fair dealing exception in Canada's Copyright Act permits students to reproduce short excerpts from copyright-protected materials for purposes such as research, education, private study, criticism and review, with proper attribution. Any other copying, communicating, or distribution of any content provided in this course, may be an infringement of copyright if done without proper license or the consent of the copyright owner, the course instructors. Examples of infringing uses of copyrighted works would include uploading materials (e.g., class lecture materials and tests) to a commercial third party web site (such as CourseHero or OneClass), or making paper or electronic copies of works for commercial purposes. For more information about students’ rights and obligations with respect to copyrighted works, consult the Fair Dealing Guidance for Students document on the Library’s Copyright website.

Other Course Information:

University Policies

Academic Consideration

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The Academic Misconduct Policy is detailed in the University Calenders:


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