Transcript MSU key messages

Symptoms of nitrogen deficiency
in wheat
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Reduced tillering
Reduced root mass
Smaller leaf size
Lower leaves turn yellow and died from the
tip back
• Stunted growth and reduced tillering
• Adverse effect on spikelet formation, floret
formation, kernel fill, and grain protein
Other causes of similar symptoms
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Drought injury
Sulfur deficiency
Barley yellow dwarf virus
Wheat streak mosaic virus
Herbicide injury due to:
– Acetanilides (Stampede)
– Imidazolinone symptoms on leaf tips (Assert, Pursuit,
Scepter)
– Sulfonylurea symptoms on leaf tips (Accent, Ally, Amber,
Beacon, Classic, Express, Glean, Muster, Pinnacle, Refine)
– as-Triazines (Lexone, Sencor)
– s-Triazines (Aatrex, Atrazine, Bladex)
N deficiency conditions and patterns
• Favorable conditions:
– Lack of available nitrogen due to excessively wet
soils in the growing season.
– Drought, sandy soils, and soils low in organic
matter
– Intensive cropping with insufficient nitrogen
• Pattern in field:
– Nitrogen deficiency generally occurs in areas of
soil compaction or high crop residue which may tie
up available nitrogen early in the growing season
– Symptoms also can appear on sandy ridges,
eroded hilltops and areas where water has
accumulated and leached the nitrogen out of the
root zone
http://scarab.msu.montana.edu/Disease/DiseaseGuidehtml/webAbnutr.htm
Nitrogen deficiency
• Cool, wet weather: the plant can’t take N up
from the soil, even if the N is available (when
the temperature warms up, the plants will
recover)
• Can look like a virus (Wheat streak), but more
general chlorosis on leaves, look at the
pattern
Nitrogen
Wheat streak mosaic virus