Calcium (Ca) deficiency is a plant disorder that can be caused by insufficient level of biologically available

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar ...

in the growing medium, but is more frequently a product of low

transpiration Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. Water is necessary for plants but only a small amount of water taken up by the roots is used for growth ...

of the whole plant or more commonly the affected tissue. Plants are susceptible to such localized calcium deficiencies in low or non-transpiring tissues because calcium is not transported in the

phloem Phloem (, ) is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as ''photosynthates'', in particular the sugar sucrose, to the rest of the plant. This transport process is c ...

. This may be due to water shortages, which slow the transportation of

to the plant, poor uptake of calcium through the stem, or too much

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

in the soil.

Causes

Acidic, sandy, or coarse

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former ...

s often contain less calcium. Uneven soil moisture and overuse of

fertilizer A fertilizer (American English) or fertiliser (British English; see spelling differences) is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from ...

s can also cause calcium deficiency. At times, even with sufficient calcium in the soil, it can be in an insoluble form and is then unusable by the plant or it could be attributed to a "transport protein".University of Zurich (2011). Blossom end rot: Transport protein identified. http://phys.org/news/2011-11-blossom-protein.html Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium. Calcium and

magnesium Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...

are opposed within the plant cells, and have antagonistic interactions. As a result, a homeostatic balance between Ca and Mg within the plant is necessary for optimal growth and proper development.

Symptoms

Calcium deficiency symptoms appear initially as localized tissue

necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated diges ...

leading to stunted plant growth,

necrotic Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dige ...

leaf margins A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...

on young leaves or curling of the leaves, and eventual death of terminal buds and root tips. Generally, the new growth and rapidly growing tissues of the plant are affected first. The mature leaves are rarely if ever affected because calcium accumulates to high concentrations in older leaves. Calcium deficiencies in plants are associated with reduced height, fewer nodes, and less leaf area. Crop-specific symptoms include: ;

Apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple trees are cultivated worldwide and are the most widely grown species in the genus '' Malus''. The tree originated in Central Asia, where its wild ancest ...

: ' Bitter pit' – fruit skins develop pits, brown spots appear on skin and/or in flesh and taste of those areas is bitter. This usually occurs when fruit is in storage, and

Bramley apple ''Malus domestica'' (Bramley's Seedling, commonly known as the Bramley apple, or simply Bramley, Bramleys or Bramley's) is a cultivar of apple that is usually eaten cooked due to its sourness. The variety comes from a pip planted by Mary Ann Brai ...

s are particularly susceptible. Related to boron deficiency, "water cored" apples seldom display bitter pit effects. ;

Cabbage Cabbage, comprising several cultivars of ''Brassica oleracea'', is a leafy green, red (purple), or white (pale green) biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage ( ''B.&n ...

lettuce Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, ...

and

brussels sprout The Brussels sprout is a member of the Gemmifera cultivar group of cabbages (''Brassica oleracea''), grown for its edible buds. The leaf vegetables are typically 1.5–4.0 cm (0.6–1.6 in) in diameter and resemble miniature cabbages ...

s :There is some evidence that plants like lettuce are more likely to experience tipburn (burned edges of leaves) if they're experiencing a deficiency of calcium. ;

Carrot The carrot ('' Daucus carota'' subsp. ''sativus'') is a root vegetable, typically orange in color, though purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild carrot, ''Daucus carota'', na ...

: ' Cavity spot' – oval spots develop into craters which may be invaded by other disease-causing organisms. ;

Celery Celery (''Apium graveolens'') is a marshland plant in the family Apiaceae that has been cultivated as a vegetable since antiquity. Celery has a long fibrous stalk tapering into leaves. Depending on location and cultivar, either its stalks, ...

: Stunted growth, central leaves stunted. ;

Tomato The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word ...

es and

pepper Pepper or peppers may refer to: Food and spice * Piperaceae or the pepper family, a large family of flowering plant ** Black pepper * ''Capsicum'' or pepper, a genus of flowering plants in the nightshade family Solanaceae ** Bell pepper ** Chili ...

s:'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 exacerbate blossom end rot. Water management and preventing water stress is key to minimizing its occurrence.:Although it was once common knowledge that blossom end rot was caused by calcium deficiencies, there are also other proposed causes.

Treatment

Calcium deficiency can sometimes be rectified by adding

agricultural lime Agricultural lime, also called aglime, agricultural limestone, garden lime or liming, is a soil additive made from pulverized limestone or chalk. The primary active component is calcium carbonate. Additional chemicals vary depending on the mineral ...

to acid soils, aiming at a pH of 6.5, unless the subject plants specifically prefer acidic soil. Organic matter should be added to the soil to improve its moisture-retaining capacity. However, because of the nature of the disorder (i.e. poor transport of calcium to low transpiring tissues), the problem cannot generally be cured by the addition of calcium to the roots. In some species, the problem can be reduced by prophylactic spraying with calcium chloride of tissues at risk. Plant damage is difficult to reverse, so corrective action should be taken immediately, supplemental applications of

calcium nitrate Calcium nitrate, also called ''Norgessalpeter'' (Norwegian salpeter), is an inorganic compound with the formula Ca(NO3)2(H2O)x. The anhydrous compound, which is rarely encountered, absorbs moisture from the air to give the tetrahydrate. Both anhyd ...

at 200 ppm nitrogen, for example. Soil pH should be tested, and corrected if needed, because calcium deficiency is often associated with low pH. Early fruit will generally have the worst symptoms, with them typically lessening as the season progresses. Preventative measures, such as irrigating prior to especially high temperatures and stable irrigation will minimize the occurrence.

References

*Hopkins, William G., Norman P.A. Hüner. ''Introduction to Plant Physiology''. London:

Wiley & Sons John Wiley & Sons, Inc., commonly known as Wiley (), is an American multinational publishing company founded in 1807 that focuses on academic publishing and instructional materials. The company produces books, journals, and encyclopedias, in p ...

, 2009. *Nguyen, Ivy. “Increasing Vitamin D2 with Ergosterol for Calcium Absorption in Sugarcane.”

UC Davis The University of California, Davis (UC Davis, UCD, or Davis) is a public land-grant research university near Davis, California. Named a Public Ivy, it is the northernmost of the ten campuses of the University of California system. The institu ...

COSMOS. July 2009. 17 October 2010
NGUYEN_IVY.pdf
*Simon, E.W. “The Symptoms of Calcium Deficiency in Plants.” ''

New Phytologist ''New Phytologist'' is a peer-reviewed scientific journal published on behalf of the New Phytologist Foundation by Wiley-Blackwell. It was founded in 1902 by botanist Arthur Tansley, who served as editor until 1931. Topics covered ''New Phytolo ...

'' 80 (1978):1-15.

Notes

External links

Blossom end Rot video

Example of blossom end rot on Roma tomatoes

- The Ohio State University Extension {{PlantMineralDeficiency Physiological plant disorders Biology and pharmacology of chemical elements Deficiency (Plant) Tomato diseases