ºÝºÝߣ

ºÝºÝߣShare a Scribd company logo

Calcium- secondary nutrient

?Download as PPTX, PDF?
?
B
BHUKKYA JEEVAN NAIK

Calcium- sources and content ¨C forms of calcium in soils ¨C Functions ¨C Deficiency symptoms ¨C corrective measures

1 of 23
Downloaded 20 times
Calcium- Sources and Content ¨C Forms of calcium in soils ¨C Functions ¨C Deficiency symptoms ¨C corrective measures JEEVAN NAIK. B M. Sc, (ag) ANGRAU SPEAKER
SECONDARY NUTRIENTS (Ca) These nutrients received little attention due to their inadvertent application through fertilizers and irrigation water. ? (NH4)2SO4 (100 kg) supplies 20 kg N and 24 kg S ? Ca(H2PO4)2 supplies 16 kg of P2O5, 21 kg of Ca and 12 kg of S ? K2SO4 supplies 52 kg K2O and 18 kg of S ? Lime (CaO) which contains Ca and Mg is applied to raise the pH ? Sulphur compounds are used to lower the pH of soil ? Irrigation water may contain on an average 25 ppm of SO4 , 50 ppm of Ca and 5 ppm of Mg.
Content and sources of soil calcium : ? The Ca concentration of the earth¡¯s crust is about 3.20 %, ? It may be as low as 0.015 % in humid region to as high as 5 % in arid region¡­??? ? The major sources of Ca are the weathered products of rocks and minerals
Mineral Chemical formula Total CaO (%) Calcite CaCO3 56.0 Apatite Ca10(PO4)6 50.0 ¨C 53.2 Dolomite CaCO3.MgCO3 33.2 Gypsum CaSO4.2H2O 32.2 Sources of Ca (secondary minerals)
Besides these secondary minerals, primary minerals like ? Augite (18.7%), ? Hornblende (4.6%), ? Anorthite (10.0 ¨C 20.0 %) ? Epidote (22.0-25.0%) etc., are the sources of calcium in the soil.
Forms of calcium in soils ?Mineral particles : Calcium is mostly present as primary minerals such as anorthite, and basic rocks like basalt, gabbro. They all release Ca on weathering. ?Calcium carbonate : Calcite mineral is very common. The nodular form of calcium carbonate and amorphous calcium carbonate exist.
Nodular form of calcium Amorphous calcium
? Simple salt : it is present in many simple salts such as ? Calcium chloride(CaCl2), ? Calcium sulphate(CaSO3), ? Calcium nitrate and (Ca(NO3)2) ? Calcium bicarbonate(Ca(HCO3)2). ?Exchangeable calcium : Of all the cations on the exchange complex of soils Ca2+ is the most dominant cation.
1. Absorbed by organisms : ? Legumes use much more calcium than grasses. ? Prolonged cropping like alfalfa on sandy soils depletes Ca resource. 2. Losses due to leaching : ? Due to rainfall , irrigation and permeability of the soil ? Greater loss of calcium in Light textured soil ? Leaching losses range between 84 to 224 kg ha-1 The fate of released calcium
3. Adsorbed by clay colloids : ? If the activity of calcium suddenly increases, there will be a shift in equilibrium with subsequent adsorption of some Ca2+ by exchange complex ? If the activity of calcium decreases the adsorbed calcium releases into soil solution 4. Reprecipated calcium (precipitating a substance from a solution) ? Calcium is reprecipitated as secondary calcium compounds in arid climate ? In arid region, due to low rainfall, Ca in soil solution will be precipitated as least soluble calcium compounds
Factors affecting the availability of ¡°Ca¡± to plants ? Calcium that is in the form of an insoluble compound is not available to plants. ? Since calcium is a positively charged ion, ? Clay and organic particles which are negatively charged. ? Positively charged ions adsorbed to soil particles are termed "exchangeable ions¡° ? Soil analysis determines the level of exchangeable calcium ions,
? Soil pH ? Usually soils with a higher pH level contain more available calcium. ? CEC ? A higher CEC indicates a higher capacity of the soil to adsorb and hold calcium, and therefore higher calcium availability. ? Presence of competing ions ? Such as sodium (Na+), potassium (K+), and magnesium (Mg+2). ? Decrease calcium uptake by plants. ? Sodium ions can replace the adsorbed calcium, damage soil structure and decreases calcium availability.
Mobility and uptake of calcium by plants ? Ca uptake by the plant is passive. ? Ca mobility in the plant takes places mainly in the xylem, together with water. ? Therefore calcium uptake is directly related to the plant transpiration rate. Conditions of ? high humidity, cold, low transpiration rates, and Salinity buildup may result in calcium deficiency. because it decreases the water uptake by the plant.
? The sufficiency Ca range is between 0.2 ¨C 1.0 %. ? Calcium is absorbed by the plant as Cationic form (Ca 2+), ? Calcium deficiency will appear (<0.2% Ca) Though calcium is highly mobile in soil, in the plant system it is the immobile nutrient ? in younger leaves (die back or burns) and ? in fruits (blossom end rot, bitter pit), because they have a very low transpiration rate.
? Participates in metabolic processes of other nutrients uptake. ? Promotes proper plant cell elongation. ? Strengthen cell wall structure ? Participates in enzymatic and hormonal processes. ? Helps in protecting the plant against heat stress ? Helps in protecting the plant against diseases Functions of calcium in plants
?Affects fruit quality. ? It plays a role in mitosis (cell division) and helps to maintain the chromosome structure. ? Has a role in the regulation of the stomata. ?Essential co-factor or an activator of a number of enzymes like hydrolases. ? It activates phospholipase, arginine kinase, amylase and ATPase enzymes.
? Failure or desiccation of terminal bud development. ? No unfolding of new leaves in corn, whose tips are colourless ? Chlorosis of young leaves followed by distortion of the growing points of the stem. ? In fruit trees, the death of growing points followed by die back. ? In guava, the old leaves are chlorotic with red brown spots. ? In apple, the discoloration of the fruit meat, the condition generally referred to as ¡°bitter pit¡±. Deficiency symptoms
? In Brassica, severe loss of color in young leaves, terminal bud leaves are hooked, leaves below become cup shaped. Old leaves collapse due to terminal bud disintegration. ? Blossom end rot in tomato is due to Ca deficiency
blossom end rot
Die back
Chlorotic with red brown spots
Bitter pit Discoloration
?Correction measures Calcium as a plant nutrient is more important in calcium deficient acid soils. ? The application of carbonate or sulphate salts of calcium @ 2 ¨C 4 q ha-1 in furrows could increase the yield by 48 %.

More Related Content

Calcium- secondary nutrient

  • 1. Calcium- Sources and Content ¨C Forms of calcium in soils ¨C Functions ¨C Deficiency symptoms ¨C corrective measures JEEVAN NAIK. B M. Sc, (ag) ANGRAU SPEAKER
  • 2. SECONDARY NUTRIENTS (Ca) These nutrients received little attention due to their inadvertent application through fertilizers and irrigation water. ? (NH4)2SO4 (100 kg) supplies 20 kg N and 24 kg S ? Ca(H2PO4)2 supplies 16 kg of P2O5, 21 kg of Ca and 12 kg of S ? K2SO4 supplies 52 kg K2O and 18 kg of S ? Lime (CaO) which contains Ca and Mg is applied to raise the pH ? Sulphur compounds are used to lower the pH of soil ? Irrigation water may contain on an average 25 ppm of SO4 , 50 ppm of Ca and 5 ppm of Mg.
  • 3. Content and sources of soil calcium : ? The Ca concentration of the earth¡¯s crust is about 3.20 %, ? It may be as low as 0.015 % in humid region to as high as 5 % in arid region¡­??? ? The major sources of Ca are the weathered products of rocks and minerals
  • 4. Mineral Chemical formula Total CaO (%) Calcite CaCO3 56.0 Apatite Ca10(PO4)6 50.0 ¨C 53.2 Dolomite CaCO3.MgCO3 33.2 Gypsum CaSO4.2H2O 32.2 Sources of Ca (secondary minerals)
  • 5. Besides these secondary minerals, primary minerals like ? Augite (18.7%), ? Hornblende (4.6%), ? Anorthite (10.0 ¨C 20.0 %) ? Epidote (22.0-25.0%) etc., are the sources of calcium in the soil.
  • 6. Forms of calcium in soils ?Mineral particles : Calcium is mostly present as primary minerals such as anorthite, and basic rocks like basalt, gabbro. They all release Ca on weathering. ?Calcium carbonate : Calcite mineral is very common. The nodular form of calcium carbonate and amorphous calcium carbonate exist.
  • 7. Nodular form of calcium Amorphous calcium
  • 8. ? Simple salt : it is present in many simple salts such as ? Calcium chloride(CaCl2), ? Calcium sulphate(CaSO3), ? Calcium nitrate and (Ca(NO3)2) ? Calcium bicarbonate(Ca(HCO3)2). ?Exchangeable calcium : Of all the cations on the exchange complex of soils Ca2+ is the most dominant cation.
  • 9. 1. Absorbed by organisms : ? Legumes use much more calcium than grasses. ? Prolonged cropping like alfalfa on sandy soils depletes Ca resource. 2. Losses due to leaching : ? Due to rainfall , irrigation and permeability of the soil ? Greater loss of calcium in Light textured soil ? Leaching losses range between 84 to 224 kg ha-1 The fate of released calcium
  • 10. 3. Adsorbed by clay colloids : ? If the activity of calcium suddenly increases, there will be a shift in equilibrium with subsequent adsorption of some Ca2+ by exchange complex ? If the activity of calcium decreases the adsorbed calcium releases into soil solution 4. Reprecipated calcium (precipitating a substance from a solution) ? Calcium is reprecipitated as secondary calcium compounds in arid climate ? In arid region, due to low rainfall, Ca in soil solution will be precipitated as least soluble calcium compounds
  • 11. Factors affecting the availability of ¡°Ca¡± to plants ? Calcium that is in the form of an insoluble compound is not available to plants. ? Since calcium is a positively charged ion, ? Clay and organic particles which are negatively charged. ? Positively charged ions adsorbed to soil particles are termed "exchangeable ions¡° ? Soil analysis determines the level of exchangeable calcium ions,
  • 12. ? Soil pH ? Usually soils with a higher pH level contain more available calcium. ? CEC ? A higher CEC indicates a higher capacity of the soil to adsorb and hold calcium, and therefore higher calcium availability. ? Presence of competing ions ? Such as sodium (Na+), potassium (K+), and magnesium (Mg+2). ? Decrease calcium uptake by plants. ? Sodium ions can replace the adsorbed calcium, damage soil structure and decreases calcium availability.
  • 13. Mobility and uptake of calcium by plants ? Ca uptake by the plant is passive. ? Ca mobility in the plant takes places mainly in the xylem, together with water. ? Therefore calcium uptake is directly related to the plant transpiration rate. Conditions of ? high humidity, cold, low transpiration rates, and Salinity buildup may result in calcium deficiency. because it decreases the water uptake by the plant.
  • 14. ? The sufficiency Ca range is between 0.2 ¨C 1.0 %. ? Calcium is absorbed by the plant as Cationic form (Ca 2+), ? Calcium deficiency will appear (<0.2% Ca) Though calcium is highly mobile in soil, in the plant system it is the immobile nutrient ? in younger leaves (die back or burns) and ? in fruits (blossom end rot, bitter pit), because they have a very low transpiration rate.
  • 15. ? Participates in metabolic processes of other nutrients uptake. ? Promotes proper plant cell elongation. ? Strengthen cell wall structure ? Participates in enzymatic and hormonal processes. ? Helps in protecting the plant against heat stress ? Helps in protecting the plant against diseases Functions of calcium in plants
  • 16. ?Affects fruit quality. ? It plays a role in mitosis (cell division) and helps to maintain the chromosome structure. ? Has a role in the regulation of the stomata. ?Essential co-factor or an activator of a number of enzymes like hydrolases. ? It activates phospholipase, arginine kinase, amylase and ATPase enzymes.
  • 17. ? Failure or desiccation of terminal bud development. ? No unfolding of new leaves in corn, whose tips are colourless ? Chlorosis of young leaves followed by distortion of the growing points of the stem. ? In fruit trees, the death of growing points followed by die back. ? In guava, the old leaves are chlorotic with red brown spots. ? In apple, the discoloration of the fruit meat, the condition generally referred to as ¡°bitter pit¡±. Deficiency symptoms
  • 18. ? In Brassica, severe loss of color in young leaves, terminal bud leaves are hooked, leaves below become cup shaped. Old leaves collapse due to terminal bud disintegration. ? Blossom end rot in tomato is due to Ca deficiency
  • 21. Chlorotic with red brown spots
  • 23. ?Correction measures Calcium as a plant nutrient is more important in calcium deficient acid soils. ? The application of carbonate or sulphate salts of calcium @ 2 ¨C 4 q ha-1 in furrows could increase the yield by 48 %.