Disentangling the origin of chemical differences using GHOST
Breeding for nitrogen use efficiency in cereals
1. Breeding for nitrogen use efficiency in
cereals
Presented by
Sachin Kumar H M
MAITAFO182
MSc Agri (GPB)25/11/2017 Dept of Genetics and Plant Breeding 1
6. NUE of different cereals
0
5
10
15
20
25
30
35
40
45
50
Wheat Rice triticale Barley Maize oat
Series 1
Wheat
Rice
triticale
Barley
Maize
oat
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7. Effects of excess of nitrogen fertilizer
application
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Eutrophication Lodging
DiseasesFertilizer burn
8. Deficiency of nitrogen
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Yellowing of basal leaves
Chlorosis
Decrease in Kernel color
Stunted growth
9. Definitions
NUE: Nitrogen use efficiency is the
grain production per unit of N
available in soil and applied
externally.
Grain yield
(Available N in soil + applied
fertilizer)
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NUE =
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NUE
Nitrogen uptake
efficiency
Nitrogen utilization
efficiency
(plant (or shoot) N content)
UpE =
(N supply)
(grain mass)
UtE =
(plant (or shoot) N content)
11. Physiological basis of NUE
• Nitrogen uptake
• Nitrogen assimilation
• Transamination
• Remobilization
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13. Nitrate uptake
Low affinity transport
system
high affinity transport
system
No
-3
No
-3
No
-3
No
-3
No
-3
No
-3 No
-3
No
-3
No
-3
No
-3
No
-3
No
-3
No
-3
No
-3 No
-3
No
-3
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Remobilization
Protease
Chloroplast
protein
Amino acids
Transamination
GDHGlutamate pool 2-Oxaloglutarate Ammonia
AMT
18. Transporter genes Genes
Nitrate transporter gene (High
affinity )
NRT2.1, 2.2, 2.3, 2.4
Nitrate transporter gene (low
affinity)
NRT1 or NPF
Ammonium Transporter AMT1.1, 1.2
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Molecular basis of NUE
N Assimilation genes
NR Nitrate reductase NR1, NR2
NiR Ferredoxin-nitrite
reductase
NiR1, NiR2
19. Gene family Genes
GDH GDH1, GDH2, GDH3,
GDH4
GS GS1, 2, 3, 4, 5
GOGAT GOGAT1, 2
Aminoacid Biosynthesis Genes
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Nitrogen uptake governing genes
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Location of detected QTLs for physiological traits
governing NUE
25. Genetic basis of NUE
Nature of gene action for nitrogen use efficiency (NUE)
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Type of Gene action Authors
Additive gene action Mc Kendry et al., 1988
Additive and Non additive in F1 hybrids Le Gouis et al., 2002
Additive action for F2 progenies of wheat Yildirim et al., 2007
27. • 6 x 6 diallel at low and high N levels.
• Mean squares of GCA and SCA significant
under both low-N and high-N
• GCA > SCA
• Additive genetic variance > non-additive
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28. Traits correlated with NUE
Chlorophyll content
Dry weight of root
Dry weight of shoot
Grain weight
Harvest index
Number of productive tillers
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29. Strategies to improve NUE
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Conventional breeding approaches
• Selection
• Backcross
Molecular and genetic engineering approaches
• Quantitative Trait Loci and Candidates Genes
• Transgenes for NUE