Plant Nutrients Jason Gehrke 2164A, B, E, F, G

Macro/Micro Nutrients Nitrogen Phosphorus Potassium Magnesium Calcium Sulfur Micro Boron Copper Chlorine Manganese Molybdenum Nickel Zinc Iron

Macro-Nutrients Nitrogen Phosphorus Amino acid synthesis Proteins Chlorophyll Enzymes Phosphorus Storage and transfer of energy as ATP Proteins Co-enzymes Make phospholipids and nucleic acids

Macro-Nutrients Potassium Magnesium Maintain plant cell structure (turgidity) Plant cell processes Enzyme activation Sugar translocation Magnesium Central atom of the chlorophyll molecule Aids in phosphorus uptake

Macro-Nutrients Calcium Sulfur Maintains Plant cell walls and cell division Sulfur Required for several amino acids Cell respiration Crucial for protein synthesis

Deficienies Color Plant Stunting Decrease in flower budding Yellowing of leaves (chlorosis) Nitrogen Potassium Plant Stunting Decrease in flower budding Decrease in Plant Size

MicroNutrients Boron Copper Flowering, fruiting, cell division Translocation of sugars in plants Copper Chlorophyll synthesis Catalyst for respiration Catalyst for carbohydrate and protein metabolism

MicroNutrients Manganese Molybdenum Crucial in chlorophyll synthesis Phosphorylation Activation of enzymes Carbohydrate metabolism Molybdenum Protein Synthesis Required by some enzymes

MicroNutrients Zinc Iron An enzyme activator Chlorophyll production Enzyme reactions Chlorophyll production

Nutrient Uptake Process Minerals dissolve in water and become small electrically charged particles (ions) Soil surface is negatively charged Positive minerals bind to negative soil surface Water displaces the minerals in the soil Free minerals are absorbed by plant root cells

pH Indicates the level of acidity or alkalinity Acidity pH < 7 (less than) Alkalinity pH > 7 (greater then) Plants prefer soil pH around 6.0-7.0 Many nutrients are abundant in this range pH preference is different for each plant Low pH can kill microorganism Example: nitrogen fixing bacteria

pH and Nutrient Availability www.avocadosource.com/ tools/FertCalc_files/pH.htm

Nutrient Sources Natural Organisms Crop Residues Animal Wastes Commercial Fertilizers

Nutrient Sources Natural Organisms Nodulation Mycorrhiza http://www.arspb.org/publications/soy97/rootc.jpg

Nodulation Symbiotic relationship is Mutualism between legume plants roots and bacteria Rhizobacteria- living soil bacteria convert nitrogen gas N2 to ammonia NH3 Attach to root hairs of plants and plant roots curl around them Bacteria stimulate the root cortex cells to divide Form a nodule www.anbg.gov.au/cpbr/ program/ub2002/rhiz_host.htm

Nodulation Nodule is a modified lateral root with own meristem and vascular tissue. 1/3 of nitrogen for plant comes from fixation 3 different rhizobacteria, each specific to a legume species http://www.legumetechnology.co.uk/Pics/bi1.jpg

Mycorrhiza Symbiotic relationship is Mutualism Fungal hyphae closely associate with active root Fungus uses photosynthates flowing from shoot to root as a source of food Plant receives phosphate taken up by mycorrhiza from the soil http://www.apsnet.org/education/IllustratedGlossary/PhotosI-M/mycorrhiza.jpg

Crop Residues Left over crops are chopped up and plowed under soil Corn stalks Alfalfa Sunflowers http://abe.www.ecn.purdue.edu/~epados/erosbmp/images/cropresi.jpg

Animal Wastes Animal wastes differ with different Animal types Feeds fed to animals Human handling (dry or wet storage) www.ontariocorn.org/.../ soilccr_mcropres.htm

Commercial Fertilizers Types Dry granules Liquids Gas Grades (N-P-K) www.ars.org/About_Roses/ fertilizing_food.htm

Examples Nitrogen Phosphorus Potassium Ammonium Nitrate (33-0-0) dry granules Urea (45-0-0) dry granules Ammonium Sulfate (21-0-0) dry granules Phosphorus Super phosphate (0-20-0) contains 24% sulfur Potassium Potassium chloride (0-0-62) dry granules

10-10-10 http://www.agr.state.nc.us/cyber/kidswrld/plant/Fertbag.GIF

Conversions Nitrogen Phosphorus is in the form P2O5 No conversion needed 100% nitrogen Phosphorus is in the form P2O5 Atomic weight P=31, O=16 2(31) + 5(16) = 142 P = %P/total weight, so 62/142 = 0.44 P= 44% of P2O5 Potassium is in the form K2O Atomic weight K=39.1, O=16 2(39.1) + (16) = 94.2 K = %/K/total weight, so 78.2/94.2 = 0.83 K= 83% of P2O5

Example Conversion 10-25-30 In 1500 lbs of Fertilizer N= 1500 x .10 = 150 lbs P2O5= 1500 x .25 = 375 lbs K2O= 1500 x .30 = 450 lbs

Example Conversion 10-25-30 Total amount of N-P-K N= 150 Lbs In 1500 lbs of Fertilizer N= 1500 x .10 = 150 lbs P2O5= 1500 x .25 = 375 lbs K2O= 1500 x .30 = 450 lbs Total amount of N-P-K N= 150 Lbs P = 375 x .44 = 165 lbs K= 450 x .83 = 373.5 lbs

Nutrient Testing To determine how much fertilizer to apply have soil tested Take soil sample to lab Lab will test for available P & K in soil http://www.agry.purdue.edu/turf/images/fertsprd.jpg

Environmental Factors Soil Composition Sandy soils will drain faster, hold less nutrients Clay soils will retain more nutrients, but will drain slower Water/Rain Need some rain so fertilizer will dissolve if it is in dry granule form Heavy rain will cause fertilizer to leach through soil pass plant roots Too Little Water (drought conditions) and fertilizer application is worthless