REQUIREMENTS
Topic PLANT # 2031
Mr. Christensen
Nutrients
Plants needs more than carbon dioxide (CO2), water (H2O) and light they also require---- MacronutrientsRequired in larger quantities than others. MicronutrientsNeeded but in smaller amounts
Essential Plant Nutrients
Non-Fertilizers obtained from the air and waterCarbon(C) Hydrogen (H) and Oxygen (O) Primary MacronutrientsNitrogen (N), Phosphorus (P), Potassium (K),
Essential Plant Nutrients
Secondary MacronutrientsCalcium (Ca), Magnesium (Mg) and Sulfur (S) MicronutrientsBoron (B), Copper (Cu), Chlorine (Cl), Iron (Fe), Manganese (Mn), Molybdenum (Mo), Zinc (Zn) and Nickel (Ni)
Nitrogen Cycle
Physical Geography http://www.physicalgeography.net/fundamentals/9s.html
Nitrogen
Constituent of amino acids, chlorophyll and nucleic acids Plant absorbs as NO3-, NH4+, and NO2 Deficiency symptomsstunting, pale green leaves (chlorosis) and firing of lower leaves (firing of tip down the mid-vein) Mobile in the plant and soil (leaching and denitrification)
N Deficiency Chlorosis
Side-dressing corn With 28% N
Iowa State University, http://www.ent.iastate.edu/imagegal/plantpath/corn/deficiency/ndeficiency.html
28% N Fertilizer Burn
Iowa State University, http://www.ent.iastate.edu/imagegal/plantpath/corn/deficiency/ndeficiency.html
Phosphorus
Important in energy release, constituent of ATP and nucleic acids, necessary for normal development of flowers, fruits and seeds. Plant absorbs as H2PO4- (acid soils) and HPO4=, and PO4= (alkaline soils) Deficiency symptomsPurpling of lower leaves, flowers abort before forming. Mobile in the plant and fixed in the soil Most Michigan soils are high P
Phosphorus in Deficiency
N use in a corn plant Over time
P use in corn plant Over time
Iowa State University http://maize.agron.iastate.edu/images/corn/Fig55.gif
Timing and Nitrogen Rate Application Effect on Corn Yield
Irrigated McBride Sandy Loam Application Timing N rate Preplant Sidedress Lb N/acre -----------bu/acre 0 75 75 120 149 155 Why less production For N applied preplant 180 155 161 240 157 167 Diminishing Returns? For profit 200 Lb N/acre for Records 400Lb N/acre
Potassium
Important in translocation; affects cell permeability, stomatal activity, activator of many enzymes Plant absorbs as K+ Deficiency symptomsScorch or necrotic spotting (yellowish/reddish) of lower leaves (tips to margins), weak stalks
Potassium Deficiency
Iowa State University, http://www.ent.iastate.edu/imagegal/plantpath/corn/deficiency/ndeficiency.html
K use in Corn Over time
Iowa State University http://maize.agron.iastate.edu/images/corn/Fig55.gif
Reading the Fertilizer Label
1st Number Ni...