Code last year: (HPC-30806)
|Teaching method||Contact hours|
|Course coordinator(s)||dr. JC Verdonk|
|Lecturer(s)||dr. JC Verdonk|
|prof. dr. EJ Woltering|
|dr. RE Schouten|
|Examiner(s)||dr. JC Verdonk|
Language of instruction:
Assumed knowledge on:
Basic Plant Physiology.
Quality analyses of horticultural and other plant products; MSc Quality in food chains & MSc spec. Greenhouse Horticulture in MPS-Plant Sciences.
Upon harvest plants, or parts of plants, are removed from the natural sources of water, nutrients and light that sustained their previous growth and development. This results in changes in the product that alter its value, usually decreasing it. The changes arising from the act of harvesting are superimposed on other changes that are independent of harvest that likewise have an effect on product value. Alterations in the product that reduce its value are ideally avoided. Post-harvest physiology seeks to understand the physical and physiological basis of the changes that occur in products post-harvest so as to control and augment positive changes while preventing or diminishing negative changes. As well as deepening the understanding of basic physiological processes such as respiration, membrane physiology etc., the course will extend the students' knowledge of physiology in to new areas dealing with specifically post-harvest features of plants and their component parts, for example ripening and senescence, modified and controlled atmospheres, ethylene physiology, and water uptake of cut flowers.
Finally, we will look at the impact of novel technologies such as next generation sequencing, transcriptomics, proteomics and metabolomics to study the processes that happen in fruits and vegetables during post-harvest. The measurement of post-harvest quality has shifted from traditional phenomics (firmness, colour, weight, shape) to modern metabolic analyses and other high throughput approaches. We will look into the biosynthesis of natural products especially quality markers such as colour, vitamins and flavour and describe some examples of the effect of metabolic engineering on post-harvest quality.
After successful completion of this course students are expected to be able to:
- exemplify the importance of post-harvest changes in the economics and practice of horticulture;
- explain the physical means by which product temperature control is achieved;
- describe the chemistry and structure of cell membranes;
- explain the role that membranes properties play in the cold sensitivity (chilling sensitivity) of tropical products;
- explain the physiology and molecular physiology of senescence and apoptosis in plants, and their role in product quality changes and deterioration;
- explain the process of respiration, its role in the post-harvest deterioration of products, and its regulation by environmental management;
- implement the physical basis of water loss by products to explain its reduction by environmental management and product treatment and handling;
- explain and implement ethylene as a growth regulator in plants; its operation at the cellular level, the different effects it has on climacteric and non-climacteric products, and methods used to diminish ethylene-induced quality loss in products;
- implement and to compare the underlying principles and practical applications of cooling, storing and packaging of products;
- explain the changes that occur in cut-flowers post-harvest and the strategies employed to slow down post-harvest quality-loss in this class of products;
- describe the biology of Botrytis, and to explain the role that it plays in post-harvest quality loss and countermeasures to prevent this;
- outline the trends in fresh fruit and vegetable consumption and the role of this consumption for human health;
- emphasise the impact of novel high throughput technologies on the research of post-harvest physiology;
- describe the biosynthesis of selected natural products that are important for post-harvest quality and understand the possibilities of metabolic engineering.
- self study;
- 25% of final mark is derived from the mark of the practical reports;
- 75% of final mark is obtained from a written examination.
Kays and Paull. (2004). Postharvest Biology. Exon Press, Athens, GA, USA.
|Restricted Optional for:||MPS||Plant Sciences||MSc||B: Greenhouse Horticulture||2MO|
|Compulsory for:||WUQPC||BSc Minor Quality of Fresh Plant Products in Supply Chains||2MO|