Calcium deficiency (plant disorder)
Encyclopedia
Calcium deficiency is a plant disorder that can be caused by insufficient calcium in the growing medium, but is more frequently a product of low transpiration 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. This may be due to water shortages, which slow the transportation of calcium
to the plant, or can be caused by excessive usage of potassium
or nitrogen
fertilizers.
. Uneven soil moisture and over use of fertilizers can also cause calcium deficiency. At times, even when there is a lot of calcium in the soil, the calcium can be in an insoluble form and is then unusable by the plant. Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium.
Crop-specific symptoms include:
Apple : 'Bitter pit
' – fruit skins develop pits, brown spots appear on skin and/or in flesh and taste of those areas is bitter. Usually occurs when fruit is in storage. Bramley apple
s are particularly susceptible. Related to boron deficiency
, "water cored" apples seldom display bitter pit effects.
Cabbage
and Brussels sprout
s : Internal browning and "tip burn"
Carrot
: 'Cavity spot' – oval spots develop into craters which may be invaded by other disease causing organisms
.
Celery
: Stunted growth, central leaves stunted.
Tomato
es and pepper
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.
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. 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 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.
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
to the plant, or can be caused by excessive usage of potassium
Potassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...
or nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
fertilizers.
Causes
Soils that are acidic, sandy, or coarse often contain less calciumCalcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
. Uneven soil moisture and over use of fertilizers can also cause calcium deficiency. At times, even when there is a lot of calcium in the soil, the calcium can be in an insoluble form and is then unusable by the plant. Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium.
Symptoms
Calcium deficiency symptoms appear initially as localized tissue necrosis leading to 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 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.Crop-specific symptoms include:
Apple : 'Bitter pit
Bitter pit
Bitter pit is a physiological disorder believed to be induced by calcium deficiency in apple fruits.The incidence of bitter pit usually occurs during storage, but in some cases it can also develop at harvest. This disorder has been studied for more than a hundred years and many approaches have...
' – fruit skins develop pits, brown spots appear on skin and/or in flesh and taste of those areas is bitter. Usually occurs when fruit is in storage. Bramley apple
Bramley (apple)
Malus domestica 'Bramley's Seedling' is a cultivar of apple which is usually eaten cooked due to its sourness...
s are particularly susceptible. Related to boron deficiency
Boron deficiency (plant disorder)
Boron deficiency is an uncommon disorder affecting plants growing in deficient soils and is often associated with areas of high rainfall and leached soils. Boron may be present but locked up in soils with a high pH, and the deficiency may be worse in wet seasons. Most of what is known about boron...
, "water cored" apples seldom display bitter pit effects.
Cabbage
Cabbage
Cabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
and Brussels sprout
Brussels sprout
The Brussels sprout is a cultivar of wild cabbage grown for its edible buds. The leafy green vegetables are typically 2.5–4 cm in diameter and look like miniature cabbages. The sprout is Brassica oleracea, in the "gemmifera" group of the family Brassicaceae...
s : Internal browning and "tip burn"
Carrot
Carrot
The carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh...
: 'Cavity spot' – oval spots develop into craters which may be invaded by other disease causing organisms
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
.
Celery
Celery
Apium graveolens is a plant species in the family Apiaceae commonly known as celery or celeriac , depending on whether the petioles or roots are eaten: celery refers to the former and celeriac to the latter. Apium graveolens grows to 1 m tall...
: Stunted growth, central leaves stunted.
Tomato
Tomato
The word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...
es and pepper
Capsicum
Capsicum is a genus of flowering plants in the nightshade family, Solanaceae. Its species are native to the Americas where they have been cultivated for thousands of years, but they are now also cultivated worldwide, used as spices, vegetables, and medicines - and have become are a key element in...
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.
Treatment
Calcium deficiency can sometimes be rectified by adding Agricultural limeAgricultural 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...
to acid soils, aiming at a pH
Soil pH
The soil pH is a measure of the acidity or basicity in soils. pH is defined as the negative logarithm of the activity of hydrogen ions in solution. It ranges from 0 to 14, with 7 being neutral. A pH below 7 is acidic and above 7 is basic. Soil pH is considered a master variable in soils as it...
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. 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 take corrective action immediately. Make supplemental applications of calcium nitrate
Calcium nitrate
Calcium nitrate, also called Norgessalpeter , is the inorganic compound with the formula Ca2. This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate. It is mainly used as a component in fertilizers but is found other applications...
at 200 ppm nitrogen. Test and correct the pH if needed because calcium deficiency is often associated with low pH.
External links
- Blossom end Rot video
- Example of blossom end rot on Roma tomatoes
- Blossom End Rot - symptoms, cause and management - The Ohio State University Extension