Drought Damage
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During prolonged days of high temperatures and increased stress, plants try to maintain their water balance by reducing water loss through stomatal closure, which may result in foliage wilting, abnormal growth and, in severe cases, plant death. |
Sun Scald
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Sun scald is a non-pathogenic disease found on a number of plants, including ornamentals, vegetables and fruits. This type of damage occurs when plants are exposed to too much direct sunlight. The injuries are more severe on stressed, weakened or recently transplanted plants. |
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Physiological Fruit Disorders: Blossom-End Rot
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A localized calcium (Ca) deficiency in the distal end of the fruit results in blossom-end rot. Fruit and undeveloped leaves have low transpiration rates and, therefore, are subject to this physiological disorder. Because calcium is not a highly mobile element, deficiency can occur with water supply fluctuations, high salt levels, the use of ammonium nitrogen and moisture extremes. Both blossom-end rot and sunscald are physiological disorders that cannot spread from plant to plant. |
Frost/freeze damage
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Alternate freezing and thawing of plant tissues can destroy plant cell walls, often killing tender plants. In hardier plants, flowers, buds or leaves may blacken or become distorted. In woody plants bark can split if damage is severe. |
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