- Calcium deficiency (plant disorder)
Calcium (Ca) deficiency is a plant disorder that can be caused by insufficient calcium in the growing medium, but is more frequently a product of a compromised nutrient mobility system in the plant. [cite web|title= Plant Physiology Online: 5.1 Symptoms of Deficiency In Essential Minerals|url=http://4e.plantphys.net/article.php?ch=t&id=289] This may be due to water shortages, which slow the transportation of
calcium to the plant, or can be caused by excessive usage ofpotassium ornitrogen fertilizers.fact|date=February 2008ymptoms
Calcium deficiency symptoms appear initially as generally stunted plant growth,
necrotic leaf margins on young leaves or curling of the leaves, and eventual death of terminal buds and root tips. Generally the new growth of the plant is affected first. The mature leaves may be affected if the problem persists. [cite web|url= http://links.jstor.org/sici?sici=0028-646X%28197801%2980%3A1%3C1%3ATSOCDI%3E2.0.CO%3B2-9 |title=The Symptoms of Calcium Deficiency in Plants |author=E. W. Simon|pages=2-4]Crop-specific symptoms includefact|date=February 2008:
; Apple : '
Bitter pit ' – fruit skins develop pits, brown patches appear in flesh and taste becomes bitter. Can occur when fruit is in storage. Bramley apples are particularly susceptible.;Cabbage andBrussels sprout s : Internal browning.;Carrot : 'Cavity spot ' – oval spots develop into craters which may be invaded by other disease causing organisms. [cite web|url= http://www.uga.edu/vegetable/carrot.html|title= The University of Georgia College of Agricultural and Environmental Sciences, Department of Horticulture - Carrot|author=Dr. Harry A. Mills|pages=3-4] ;Celery : Stunted growth, central leaves stunted.;Tomato es and peppers : 'Blossom end rot' – Symptoms start as sunken, dry decaying areas at the blossom end of the fruit, furthest away from the stem, not all fruit on a truss is necessarily affected. Sometimes rapid growth from high-nitrogen fertilizers may cause blossom end rot.Treatment
Calcium deficiency can be rectified by adding
Agricultural lime to acid soils, aiming at a pH of 6.5, unless the plant in question specifically prefers acidic soil. Organic matter should be added to the soil in order to improve its moisture-retaining capacity.fact|date=February 2008Plant damage is difficult to reverse, so take corrective action immediately. Make supplemental applications of
calcium nitrate at 200 ppm nitrogen. Test and correct the pH if needed because calcium deficiency is often associated with low pH. fact|date=February 2008Notes
External links
* [http://tinypic.com/6739yo Example of blossom end rot on Roma tomatoes]
* [http://ohioline.osu.edu/hyg-fact/3000/3117.html Blossom End Rot - symptoms, cause and management] - The Ohio State University Extension
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