soil nutrients and fertilizers 24.00: explain the role of nutrients in quality plant growth
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Soil Nutrients Soil Nutrients and Fertilizersand Fertilizers
24.00: Explain the role of nutrients in 24.00: Explain the role of nutrients in quality plant growthquality plant growth
Macro vs Micro NutrientsMacro vs Micro Nutrients
• Macro nutrients are required by the plant in relatively large amounts
• Micro nutrients are required only in small amounts– minor or trace elements
Macro nutrientsMacro nutrients
• Non-mineral elements– carbon (C)– hydrogen (H)– oxygen (O)
• Primary Nutrients– Nitrogen (N)– Phosphorus (P)– Potassium (K)
• Secondary Nutrients– calcium (Ca)– magnesium (Mg)– sulfur (S)
Micro nutrientsMicro nutrients
• Iron (Fe)
• Copper (Cu)
• Zinc (Zn)
• Boron (B)
• Molybdenum (Mo)
• Manganese (Mn)
• Chlorine (Cl)
Functions of NitrogenFunctions of Nitrogen
• Promotes growth of leaves and stems
• Gives dark green color and improves quality of foliage
• Necessary to develop cell proteins and chlorophyll
NitrogenNitrogen
• Deficiency symptoms– sick, yellow-green color– short stems, small leaves, pale colored leaves
and flowers– slow and dwarfed plant growth
Nitrogen deficiencyNitrogen deficiency
Functions of PhosphorusFunctions of Phosphorus
• Stimulates early formation and growth of roots
• Provides for fast and vigorous growth and speeds maturity
• Stimulates flowering and seed development
• Necessary for the enzyme action of many plant processes
PhosphorusPhosphorus
• Deficiency symptoms– decrease in growth– slow maturity– older leaves are purplish color
Phosphorus DeficiencyPhosphorus Deficiency
Functions of PotassiumFunctions of Potassium
• Used to form carbohydrates and proteins
• Formation and transfer of starches, sugars and oils
• Increases disease resistance, vigor and hardiness
PotassiumPotassium
• Deficiency symptoms– mottled, spotted, streaked or curled leaves– scorched, burned, dead leaf tips and margins
Potassium DeficiencyPotassium Deficiency
Functions of CalciumFunctions of Calcium
• Improves plant vigor
• Influences intake and synthesis of other plant nutrients
• Important part of cell walls
CalciumCalcium
• Deficiency symptoms– small developing leaves– wrinkled older leaves– dead stem tips
Calcium DeficiencyCalcium Deficiency
Functions of MagnesiumFunctions of Magnesium
• Influences the intake of other essential nutrients
• Helps make fats
• Assists in translocation of phosphorus and fats
MagnesiumMagnesium
• Deficiency symptoms– Interveinal chlorosis-yellowing of leaves
between green veins– leaf tips curl or cup upward– slender, weak stalks
Magnesium DeficiencyMagnesium Deficiency
Functions of SulfurFunctions of Sulfur
• Promotes root growth and vigorous vegetative growth
• Essential to protein formation
SulfurSulfur
• Deficiency symptoms– young leaves are light green with lighter color
veins– yellow leaves and stunted growth
Sulfur DeficiencySulfur Deficiency
IronIron
• Functions of Iron– Essential for chlorophyll production– Helps carry electrons to mix oxygen with other
elements
• Deficiency symptoms– mottled and interveinal chlorosis in young
leaves– stunted growth and slender, short stems
Iron DeficiencyIron Deficiency
CopperCopper
• Functions– Helps in the use of Iron– Helps respiration
• Deficiency symptoms– young leaves are small and permanently wilt– multiple buds at stem tip
Copper DeficiencyCopper Deficiency
ZincZinc
• Functions– plant metabolism– helps form growth hormones– reproduction
• Deficiency symptoms– retarded growth between nodes (rosetted)– new leaves are thick and small– spotted between veins, discolored veins
Zinc DeficiencyZinc Deficiency
BoronBoron
• Functions– affects water absorption by roots– translocation of sugars
• Deficiency Symptoms– short, thick stem tips– young leaves of terminal buds are light green
at base– leaves become twisted and die
Boron DeficiencyBoron Deficiency
ManganeseManganese
• Functions– plant metabolism– nitrogen transformation
• Deficiency symptoms– interveinal chlorosis– young leaves die
Manganese DeficiencyManganese Deficiency
MolybdenumMolybdenum
• Functions– plant development– reproduction
• Deficiency symptoms– stunted growth– yellow leaves, upward curling leaves, leaf
margins burn
Molybdenum DeficiencyMolybdenum Deficiency
ChlorineChlorine
• Functions– essential to some plant processes– acts in enzyme systems
• Deficiency symptoms– usually more problems with too much chlorine
or toxicity than with deficiency
Chlorine DeficiencyChlorine Deficiency
FertilizersFertilizers
Types of FertilizersTypes of Fertilizers
• Complete
• Incomplete
• Organic
• Inorganic
• Soluble
• Insoluble
Complete vs. IncompleteComplete vs. Incomplete
• Complete has all three primary nutrients-nitrogen phosphorous & potassium– Examples: 10-10-10, 15-30-15, 20-5-20
• Incomplete DOES NOT have all three primary nutrients– Examples: 20-0-0, 0-20-0, 12-0-44
Organic FertilizersOrganic Fertilizers
• Comes from plant or animal matter and contains carbon compounds
• Examples: urea, sludge and animal tankage
Advantages of OrganicAdvantages of Organic
• Slow release of nutrients
• Not easily leached from the soil
• Add organic components to growing media
Disadvantages of OrganicDisadvantages of Organic
• Hard to get
• Not sterile
• Low nutrient content
• Expensive
Inorganic FertilizersInorganic Fertilizers
• Comes from sources other than animals or plants
• Chemical products
Advantages of InorganicAdvantages of Inorganic
• Can make the desired ratio of nutrients
• easy to get
• lower cost
Disadvantages of InorganicDisadvantages of Inorganic
• No organic material
• possible chemical building up in growing media
Soluble FertilizerSoluble Fertilizer
• Dissolve in water and are applied as a liquid solution
• Fertigation– fertilizing through irrigation water– big advantage
Insoluble FertilizerInsoluble Fertilizer
• Includes granular and slow release applied to the growing media
Granular vs. Slow ReleaseGranular vs. Slow Release
• Granular– relatively inexpensive– easy to find
• Slow Release– more expensive because it is coated– more uniform release of nutrients over time
period
Fertilizer AnalysisFertilizer Analysis
• Fertilizer analysis expresses weight as a percent of nitrogen, phosphorus and potassium
20-10-20
Fertilizer AnalysisFertilizer Analysis
• For Example– A 100 pound bag of fertilizer has an analysis
of 15-5-15. How many pounds of nitrogen, phosphorus and potassium are in the bag?
• Nitrogen: 100lbs X 15%=15lbs• Phosphorus: 100lbs X 5%=5lbs• Potassium: 100lbs X 15%=15lbs
Fertilizer RatiosFertilizer Ratios
• A fertilizer with a 10-10-10 analysis would have a 1:1:1 ratio
• A fertilizer with a 24-8-16 analysis would have a 3:1:2 ratio
• What would be the ratio for a fertilizer with an analysis of 36-18-27?
4:2:3
Application ProceduresApplication Procedures
• Banding
• Sidedressing
• Topdressing
• Perforating
• Broadcasting
• Foliar spraying
• Fertigation
BandingBanding
• Placing a band of fertilizer about two inches to the sides and about two inches below seed depth.
• DO NOT place below the seeds because fertilizer will burn the roots.
SidedressingSidedressing
• Placing a band of fertilizer near the soil surface and to the sides after seedlings emerge from the soil.
TopdressingTopdressing
• Mixing fertilizer uniformly into the top one to two inches of growing media around the plant.
PerforatingPerforating
• Placing fertilizer in 12”-18” holes drilled 18” to 24” around the canopy drip line of fruit trees. Cover the holes and fertilizer slowly dissolves.
BroadcastingBroadcasting
• Spreading fertilizer to cover the entire production area
Foliar SprayingFoliar Spraying
• Spraying micronutrients in a solution directly on plant leaves.
• Quickly corrects nutrient deficiencies
• Fertilizer concentration should not be too high or leaf burning will occur.
FertigationFertigation
• Incorporating water-soluble fertilizer into the irrigation system of greenhouse and nursery crops.
• Concentrated solutions usually pass through proportioners or injectors to dilute to the correct ratio.– Venturi-type– Positive-displacement
Venturi-typeVenturi-type
• Simple and inexpensive
• less accurate
• depends on water pressure in the hose and in the smaller tube to proportion
• Example: Hozon
Positive-displacementPositive-displacement
• More expensive
• very accurate
• physically inject and mix specific amounts of concentrated solution and water
• Examples: commander proportioners, and Smith injectors
Rules for applying fertilizersRules for applying fertilizers
• Method used should be practical, effective and cost efficient
• Method used affects nutrient availability for plant use
• Fertilizer must be dissolved and reach plant roots