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Nitrogen
Deficiency
Amy Hong
Don Smith
What is nitrogen?
● Chemical element, primarily found as gas (N2, 78% of
the atmosphere)
● Macro and primary nutrient- plants require large
amount for their growth and survival
● A part of all living cells- proteins, enzymes, nucleic
acid
● Makes up around 4% of the dry weight of plant matter
How do plants use nitrogen?
● A component of chlorophyll- essential for
photosynthesis
● The basic element of plant proteins and
genetic materials (DNA and RNA).
● Thus, essential for plant growth and
reproduction
Symptoms of deficiency
Limitation of
growth, leaf
number, and leaf
size
Nitrogen deficient tomato leaves (left) and normal
tomato leaves (right)
Nitrogen deficient plant
Normal onion (left) and nitrogen deficient onion
(right)
Normal corn (left) and nitrogen deficient corn
(right)
Symptoms
How do plants access nitrogen?
● Different chemical
forms of nitrogennitrogen gas, ammonia,
nitrate, ammonium,
nitrite, nitrous oxide,
nitric oxide
● Nitrogen cycle- nitrogen
passes around natural
and agricultural
ecosystems in a cycle
How do plants access nitrogen?
Plants absorb nitrogen as
nitrate or ammonium ions
available in the soil
through the roots
How do plants access nitrogen?
Mutualistic relationship
● Biological reduction of nitrogen to
ammonia is a highly oxygen-sensitive
process and can be performed only
by some prokaryotes
● Plants can provide oxygen protection
system to bacteria, in exchange,
bacteria provide nitrogen to plants
Nitrogen (N) - Soil Nitrification
● Decomposition of organic matter into ammonium and nitrate
● Mediated by ammonifying and nitrifying bacteria
Ammonifying bacteria
Nitrifying bacteria
(Actinomycetes)
(Nitrosomonas)
Plant residue
→
(Protein, aa, etc)
NH4+
→
Ammonium
(Nitrobacter)
NO2
Nitrite
→
NO3Nitrate
Mutualistic relationship
● Rhizobium spp. and Legume
family- changes in plant’s
root structure
● This mutualism provides the
right amount of nitrogen at
the right time
Soil or other conditions that may affect
the uptake of nitrogen by plants
● Soil texture
● Soil pH- nitrogen is less available in soil with
low pH
● Microbial population- availability of nitrogen
fixing bacteria
References
Agriculture. (n.d.). HSC Online. Retrieved May 3, 2014, from
http://www.hsc.csu.edu.au/agriculture/production/3363/nitrogen.htm
Idaho Nutrient Management. (n.d.). Idaho Nutrient Management. Retrieved May 3, 2014, from
http://www.extension.uidaho.edu/nutrient/crop_nutrient/Onions.html
Mylona, P., Pawlowski, K., & Bisseling, T. (1995). Symbiotic Nitrogen Fixation. The Plant Cell, 7(7), 869.
Nitrogen. (n.d.). EPA. Retrieved May 3, 2014, from http://www.epa.gov/oecaagct/ag101/impactnitrogen.html
Nitrogen Deficiency vs. Healthy Plant - Maize. (n.d.). Crop Nutrition. Retrieved May 3, 2014, from
http://www.yara.co.uk/crop-nutrition/crops/maize/crop-nutrition/deficiencies/n/9486-nitrogen-deficiency-vs-healthyplant---maize/
Nitrogen Free - The Nitrogen Cycle. (n.d.). Nitrogen Free - The Nitrogen Cycle. Retrieved May 3, 2014, from
http://www.nitrogenfree.com/problem/nitrogen_cycle.php.html
Reece, J. B., & Campbell, N. A. (2011). 37. Biology (9th ed., pp. 792-795). Boston: Pearson.