fpt 2093 soil_science_week_13_plant_nutrition
TRANSCRIPT
SOIL SCIENCEFPT 2093
Lecture Week 13:Plant Nutrition
En Mohd Fauzie JusohLecturer
Agrotechnology ProgrammeFaculty of Agro-Based Industry
Universiti Malaysia Kelantan (Jeli Campus) Locked Bag No.100, 17600 Jeli, Kelantan.
014-2903025/[email protected]/
Elements in Plant Nutrition
• Terms used to describe nutrient levels in plants:– Deficient: when an element is low enough to limit
yield and deficiency symptoms are visible.
– Critical range: the nutrient concentration below which a yield response to added nutrient occurs.
– Sufficient: nutrient concentration range in which added nutrient will not increase yield but can increase nutrient concentration.
– Excessive or toxic: when the concentration of essential or other elements is high enough to reduce plant growth or yield.
Elements in Plant Nutrition
• Seventeen elements are essential to plant growth.
– The three most abundant are not mineral nutrients.
• carbon, hydrogen, and oxygen
– Six of the remaining 14 are macronutrients.
• nitrogen, phosphorus, potassium, sulfur, calcium, and magnesium
– The other eight are micronutrients.
• iron, zinc, manganese, copper, boron, chloride, molybdenum, and nickel
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Essential Nutrient Criteria:
• The element is directly involved in plant nutrition
• A deficiency of an element makes it difficult or impossible for the plant to complete a vegetative or reproductive stage of development
• Thus, a shortage of an element can only be prevented or corrected by supplying the element
• Essential meaning absence or deficiency of one of these elements plants will show symptoms of deficiency
Essential Elements
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PLANT NUTRIENTS
- These elements are of the same importance to plants but the amount needed by plants varies, thus, these elements are termed as macronutrients and micronutrients- These 18 elements and their sources are as follows:
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Element and symbol Portion of plants (%)
Ion or molecule
Carbon ( C )Oxygen ( O )Hydrogen ( H )Nitrogen ( N )Calcium ( Ca )Magnesium ( Mg )Potassium ( K )Phosphorus ( P )Sulphur ( S )Chlorine ( Cl )Iron ( Fe )Boron ( B )Manganese ( Mn )Zinc ( Zn )Copper ( Cu )Molybdenum ( Mo) Cobalt ( Co )Nickel ( Ni )Silica ( Si )Sodium ( Na )Vanadium ( Va )
41.246.35.43.32.1
0.420.800.30
0.0850.011
0.00660.00450.00360.00090.0007
0.000005-----
CO2 mostly through leavesCO2, H2O, O2
HOH, H+
NH4+ , NO3
-
Ca2+
Mg2+
K-
H2PO4- , HPO4
2-
SO42-
Cl-
Fe2+ , Fe3+
BO32-
Mn2+
Zn2+
Cu2+
MoO42-
Co2+
Ni2+
Si(OH)4
Na+
VO3-
Plant nutrients, concentrations in plants and forms taken up
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Forms of nutrients taken up by plants
Essential Element Symbol Ionic Form
Carbon C CO2
Hydrogen H H+
Oxygen O CO2 , H20, O2
Nitrogen N NO3-, NH4
+
Phosphorus P H2PO4-, HPO4
2-
Potassium K K+
Calcium Ca Ca2+
Magnesium Mg Mg2+
Sulfur S SO4-
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Forms of nutrients taken up by plants
Essential Element Symbol Ionic Form
Boron B H3BO3, B(OH4)-
Iron Fe Fe3+, Fe2+
Manganese Mn Mn4+
Copper Cu Cu2+
Zinc Zn Zn2+
Molydbenum Mo MoO4-
Chlorine Cl Cl-
Nickel Ni Ni2+
Cobalt Co Co2+
Beneficial Elements
Sodium Na Na+
Silicon Si Si4+
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Functions of major nutrients
Carbon - Primary constituent of organic compounds, carbohydraes, proteins, lipids, and nucleic acids. - Reduction and oxidation of C serves as the basis for photosynthesis and respiration.-Reduced C compound serves as energy sources for most organisms.
Oxygen -Constituent of most organic compounds. -Primary role in plants as an electron acceptor. - It is oxidized in photosynthesis and reduced in respiration.
O2 + 4e- + 4 H+ 2H2O
Hydrogen All organic compounds contain hydrogen ions. Important for ionic balance. They are involved in a variety of biochemical and chemical reactions. Reduced forms of hydrogen, NADH, and NADPH are important reducing agents in oxidation-reduction reactions.
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Functions ......
Nitrogen component of proteins, nucleic acids, important in protein and chlorophyll synthesis.
Phosphorus Component of activated carbohydrates. Central role ofphosphorus is in energy transfer. Important for root growth
Potassium Occurs primarily as free ion in cell solution. Primary role is in osmotic and ionic regulation
Calcium Involved in cell division. Important in cell walls and maintenance of cell membranes
Magnesium Component of chlorophyll and cofactor for many enzymatic reactions.
Sulphur Component of amino acids and proteins. Maintain protein structure through disulfide bonds, involved in cellenergetics
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Element Deficiency SymptomsN Chlorosis, yellowing of lower leaves first, stuntingP Low photosynthesis rate, leaves & stems turn purple,
stunting, low yieldK Leaves turn light green, burning of leave margins & tips,
less roots development, weak stems, susceptible to diseaseCa Young leaves crinkled, twisted & shortMg Chlorosis of lower leavesS Yellowing of young leaves & stuntingFe Interveinal chlorosis of young leavesZn Chlorosis of veins especially of young leavesCu Chlorosis of young leavesMn Interveinal chlorosis & stuntingB General stunting, white young leavesMo Similar to N deficiencyCl Chlorosis & necrosis of leaves
PLANT NUTRIENTS