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Chapter 14: Soils and mineral nutrition - Coggle Diagram
Chapter 14: Soils and mineral nutrition
concept
mineral nutrient plays a role in plant nutrient
soil is the major source of nutrient needed for plants growth
Soil contain large amount of microbes and tiny animals that are important to plants
Essential elements to most plants
macronutrients
carbon
oxygen
hydrogen
nitrogen
potassium
calcium
phosphorus
magnesium
micronutrient
iron
chloride
copper
manganese
zinc
molybdenum
Boron
Criteria for essentiality
Necessary for the completion of full life cycle
cannot be replaced by a chemically similar element
must act inside the plant
Mineral deficiency diseases
symptoms of deficiency disease
chlorosis; yellowing of normally green leaves due to lack of chlorophyll
necrosis: death of circumscribed area of tissue as a result of disease or injury.
Harvest method:
complete removal with roots
complete removal of shoot, leaving root
wood only, leaving bark, narrow branches and root
mobile and immobile elements
Immobile elements
Boron, calcium and iron
after they have been incorporated into plant tissue, they remain in place.
mobile elements
chlorine, magnesium, nitrogen, phosphorus, potassium and sulfur
eveb after they have been incorporated into tissue they can be translocated into younger tissue.
cause of dediciency diseases
Unable to take up nutrient present in plant.
very acidic, very alkaline , dryness and waterlogging
most commonly encountered in non native crop plants or ornamental
Soil and mineral availability
The endodermis and selective absorption of substrate
endodermis prevents uncontrolled, apoplastic diffusion in roots
Mycorrhizae and the Absorption of Phosphorus
mycorrhiza: the root of plant forming a symbiotic association with soil fungi
permits plant to absorb phosphorus efficiency
soil acidity
soil pH affects the chemical form of certain elements, causing them to change solubility.
can be affected by chemical nature of the original rock.
pH between 6.5 nad 7.0 is best for many elements.
concept
Weathering
process of deriving soil from rocks
physical weathering:
break down of rock by physical forces such as wind, water movement and temperature change
coarse sand: 2.0 to 0.2 mm
fine sand: 0.2 to 0.02 mm
slit: 0.02 to 0.002 mm
clay particles : smaller than 0.002 mm
chemical weathering
involve chemical reactions
important agent are acids produced by decaying bodies especially those of plants and fungi
cation exchange
occurs when nutrient cations are attracted to charged surface of cells within the root.
Nitrogen metabolism
nitrogen assimilation
Actual incorporation of ammonium into organic molecules in the plant body.
Transamination: the transfer of an amino group from one molecule to another
other aspects of prokaryotes and nitrogen
Nitrifying bacteria: Soil bacterai than oxidize nitrogen
Nitrification: process to oxidize nitrogen by bacteria
nitrogen reduction
Process of reducing nitrogen in nitrate ion, NO3^- from an oxidattion state of +5 to the -3 state of nitrogen in amoni acid, nucleic acid and many other biological compound
NADH and NAD+ diffuse between the enzyme and the site of respiration
Obtaining nitrogen from Animals:
Carnivorous plant: derive most of their nutritions from trapping animals amd protozoans.
Nitrogen fixation
Conversion of Nitrogen gas into nitrate, nitrite or ammonium, all forms of nitrogen that are substates for a variety of enzyme.
Nitrogenase: nitrogen fixing bacterai and cynobacteria.
Forces electron and protons onto nitrogen, reducing it from +0 to the -3 oxidation state.
Nitrogen fixing prokaryotes
Cynobacteria
Anabaena
Nostoc
Actinomycetes
Frankia
Eubacteria
Phizobium
Mycorrhizae:
principle means by which most plant absorbs phosphorous
Storage of minerals within plant
all parts of plant store mineral except seeds
Phosphate , sulphate and other nutrient are stored in central vaccuole
