Plant structure and appearance varies throughout a plant’s lifecycle. It is natural for leaves to brown and fall and it is not uncommon for fruits and flowers to vary in size and shape. However, there is a range of factors that can lead to more intensive damage and irregularities. These factors are known as plant ailments.
Plant ailments are caused by diseases or problems in the production environment. Plant defects are the resulting imperfections and physical inadequacies which can decrease plant health and vitality which, in turn, reduces their nutritional and economic value.
Understanding the different types of plant defects provides the insight necessary to take appropriate actions to reduce the overall damage and prevent the spread of the disease.
There are three common categorizations of plant defects: morphological, physical, and physiological.
Examples of morphological ailments include:
- Necrosis of the plant tissue
- Excessive or limited growth
- Curvature or elongation
- Proleptic development [maturing too early]
- Metaplastic symptoms [caused by tissue morphing into another type of tissue]
- Color changes
- Seed germination within a fruit
- Poor structure of flowers or heads
- Fruits that are filled with seeds and stems [bolting]
Physical defects are imperfections, irregularities, and problems with the plants or fruits that can affect plants that are still living and plants that have already been harvested. In the case of the latter, the products are not handled with care. In the case of the former, the plants have been impacted by poor genetics or environmental problems. Such defects can reduce the marketability of products.
Common physical defects can include:
- Shriveling and wilting
- Internal drying
Physiological defects are ailments that are caused by environmental factors. These factors impact the plant’s development and change how it functions. Physiological defects are often confused with plant diseases or pathogen-induced ailments but they are not the same.
Root causes of physiological defects can include:
- High or low temperatures that lead to freezing, chilling, sunburn, or sunscald)
- Nutritional deficiencies that can lead to a range of issues like puffiness/being hollow, blossom-end rot, tip burn, or internal breakdown
- Adverse weather
- Not enough light
- Harm from pests
- Chemical injury
- Leonberger, K. et al. (n.d.). Plant Diseases, Kentucky Master Gardener Manual, Chapter 6.
- Kader, A. A. (1992). Postharvest technology of horticultural crops. Oakland, CA: University of California, Division of Agriculture and Natural Resources.