Nutritional Analysis of Wheat (Triticum aestivum L.) Germplasm in Kenya
1. Nutritional Analysis of Wheat (Triticum
aestivum L.) Germplasm in Kenya
J.N. Ndung’u*1, E.N. Kimani, and P.N. Njau
National Plant Breeding Research Centre- KARI-
Njoro,
Private Bag - 20107,
Njoro - KENYA
2. Introduction
Wheat (Triticum aestivum L.) is the most widely grown
food crop in the world.
In Kenya, it is ranked second after maize in cereal
crops research priorities.
Mineral elements are essential components of wheat
metabolism and often accumulate in grain.
Humans require at least 22 of these mineral elements
for:
Well being which can be supplied by appropriate
diet like wheat
3. .....introduction
It is estimated that over 60 percent of the
world’s 7 billion people are:
Iron deficient and over 30 percent are
zinc deficient.
In addition, protein, calcium and
magnesium deficiencies are common in :
developed and developing countries
including Kenya.
Resistant starch (RS) is known to have
healthy benefits for human
Should be encouraged to form part of
daily diet
5. Solution Challenge
1 Micronutrient supplements for children (Fe&zinc) Malnutrition
2 The Doha development agenda Trade
3 Micronutrient fortification (iron and salt Malnutrition
iodization)
4 Expanded immunization coverage for children Diseases
5 Biofortification Malnutrition
6 Deworming, other nutrition programs in school Malnutrition
7 Lowering the price of schooling Education
8 Increase and improve girl’s schooling Women
9 Community-based nutrition promotion Malnutrition
10 Provide support for women’s reproductive role Women
Reference: http://www.copenhagenconsensus.com
6. Main Objective
To Analyze the Contribution of Kenya Wheat
Cultivars to the Improved Nutrition.
7. Materials and methods
Twenty one wheat accessions (Commercial varieties, advanced
stem rust lines and one mutant line) used in this study (Table)
Accessions planted at Njoro site: (Table /Map)
Experiment design: 4x4 partially balanced lattice design,
replicated three times.
Recommended practices followed to sustain plant growth and
production of grain.
Samples in lab milled using Retsch mill
8. ……..Materials and Methods
Mineral analysis determined using AAS following the
method of Okalebo (2002). (Figure 2)
Crude protein analysis was determined using NIR method.
Resistant starch assay was determined following Megazyme
procedure RSTAR 11/02 AOAC Method 2002.02, AACC
Method 32-40
Data subjected to ANOVA using GLM (SAS : 9.1.3)
Differences between means ranked by Fisher’s least
significant difference (LSD) test
9. …..Materials and Methods
Correlation coefficients determined to establish the
relationship between the accessions.
Similarity levels obtained using MINITAB statistical
analysis software (1996).
10. Results and Discussion
The analysis of variance showed genotypes were significantly (p≤0.01)
different in mean values for minerals, RS and protein
For the mineral contents, a linear regression equation y = 0.00238x with
R2 = 0.9991 was observed eg zinc
Calibration curve for mineral analysis (Fe, Zn,
Mg and Ca)
0.2500
y = 0.0238x
R2 = 0.9991
0.2000
Absorbance
0.1500
0.1000
0.0500
0.0000
0.00 2.00 4.00 6.00 8.00 10.00 12.00
Concentration (ppm)
11. …….Results and Discussion
Sig. difference (p≤0.01)
among accessions.
Iron Concentration(ppm)
600
Mbega and Popo highest
Concentration (ppm)
500 level of 546.2 ppm and 533.5
400
300 Iron ppm respectively.
200
100 KM 14, KSSR III, KSSR IV,
0
Kulungu, Kongoni and
KS g u
KS ri
ia
I
i
III
u
a
14
e
IV
on
R
m
ha
rik
al
am
R
n
KM
R
R
ng
Kw
Chozi scoring lowest at104.5
Du
Fa
lu
Ch
R
KS
R
Ng
Ko
Ku
ppm, 95.6 ppm, 94.1 ppm,
Varieties
90.2 ppm, 82.8 ppm and 81.4
ppm respectively.
All above RDA (20-50
ppm)
12. ……Results and Discussion
Sig. difference (p≤0.01)
Zinc Concentration among accessions.
Nyangumi scored
Concentration (ppm)
250
200
150
100 Zinc
highest at 218.2 ppm
50
0 Seven varieties had
u
KS ri
ia
conc. lower than 100
I
i
III
u
a
14
e
IV
on
R
m
ha
rik
ng
al
am
R
KM
R
R
ng
Kw
Du
Fa
lu
Ch
R
KS
R
Ng
Ko
Ku
KS
Accessions
ppm and they include
KM 14, Njoro BW II,
Chiriku, KSSR I, Paka,
Fahari and KSSR IV
All above RDA 50 ppm
13. ……Results and Discussion
Differences in iron and zinc conc. among varieties is
attributed to:
Allelic variation at a chromosomal locus that promotes early
senescence and remobilization of protein, iron and zinc
from senescing leaves to seeds.
Despite planting at same E, Iron and zinc contents are
significantly influenced by:
Date of planting, genotype and environment
Late planting and irrigation can significantly increase the
iron and zinc contents.
Seeding rates or nitrogen fertilization do not significantly
affect levels of iron and zinc in wheat grain
14. ……Results and Discussion
Magnesium Concentration
Sig. difference (p≤0.01)
among genotypes.
Concentration (ppm)
2500
2000
Popo variety scored
1500 highest at 1988.3 ppm
1000
500
Magnesium
but not significantly (p
0 ≥0.01) differenr to Chozi
at 1927.7 ppm
Fa wII
KS R R i
Te ng u
He ia
M o ni
Nj R I
Ch III
K. am i
R bo
KMg a
lu n i
Ny Kw o
Po u
Ch ozi
M ma
14
Du oe
R II
an ale
KS ka
Pa IV
r
Ng um
KS ha
rik
p
Ku bu
R
r
KS m
be
B
R
R
ng
g
Ko
Chiriku recorded a low
Accessions
of 350.9 ppm.
All above RDA 350 ppm
15. ……Results and Discussion
Calcium Concentration (ppm)
Sig. difference (p≤0.01)
Concentration (ppm)
700 among accessions.
600
500
400
Variety Kwale scored
300 highest at 602.2 ppm
200 Calcium
100 Chiriku variety having
0
lowest concentration of
KS h I
KS m u
KS R Ra ri
Hemia
B I
Ku bu i
Ch III
K. a i
R bo
KMg a
Ny K po
Te ng i
Poiku
r i
be a
14
D roe
R II
le
R a
Pa IV
M on
Fa wI
Ch oz
Ngg um
lu n
Nj R
M um
143.8 ppm
KS k
an wa
R
R
ng
Ko
Accessions All low RDA 1000 ppm
16. ……Results and Discussion
GxE effects influence wheat grain magnesium and calcium
contents
Increasing conc of essential mineral elements in wheat grain
can be also done by:
Application of mineral fertilizers
Breeding wheat varieties with increased ability to acquire
and accumulate these minerals in grain through e.g induced
mutation
17. ……Results and Discussion
Resistant Starch Concentration (g/100g) Sig. difference (p≤0.01)
among genotypes.
Concentration (g/100g)
0.12
0.1
0.08
KSSR II had highest
0.06 conc. of 0.1 g/100g
0.04
0.02 followed closely by
0
Resistant Starch Njoro BW II with a
KS ahwII
R mb u
R R Ii
a
FB I
Ku b i
Ch o I
Hemi i
R o
KMg a
an wa o
Teung i
Poiku
r zi
be a
14
Duroe
Ch III
Ngg u le
NjR Ra
KS a IV
KS R a r
M go n
value of 0.04 g/100g.
K. a m
l un
M m
Ny K p
k
R
P
n
Ko
KS
Accessions Paka variety had lowest
conc. of 0.001 g/100g.
18. ……Results and Discussion
Wheat varieties e.g KSSR II high in RS can be:
Associated with improved gut health through raising Short Chain
Fatty acids e.g Butyrate
Reduction of colon cancer
low supply of these acids is associated with increased risk of
non-infectious diseases.
Good RS contributes to bowel good health by:
Encouraging the growth of healthy bacteria in the bowel
Discourages the growth of potentially harmful bacteria
19. ……Results and Discussion
Sig. difference (p≤0.01) among
genotypes.
KSSR II and Popo at 18.1 percent
and 17.8 percent Protein Concentration (% )
Chiriku recorded the lowest
Concentration (%)
20
percent at 12.2 although: 15
It was still above 11 percent
10 Protein
5
that is described as desirable by
0
millers and bakers.
KS ah II
KS emg u
KS R Ra ri
Hemia
B I
Ku bu i
Ch III
K . a mi
R bo
KMg a
Ny K po
T n i
Poiku
r i
be a
14
D roe
R II
Ngg u le
R a
Pa IV
M on
Ch oz
lu n
F w
Nj R
M um
KS k
an wa
R
R
Higher the protein level, higher ng
Ko
the nutrition and premium paid by Accessions
millers
Used in improvement of weak soft
wheat with low protein
20. ……Results and Discussion
Table: Phenotypic correlation coefficient of minerals, RS and protein
Calcium Iron Magnesium Zinc RS Protein
Calcium 1.000 0.065 0.581 0.575 -0.160 0.366
0.780 0.006 0.006 0.488 0.103
Iron 1.000 0.234 0.244 -0.135 0.129
0.308 0.287 0.560 0.577
Magnesium 1.000 0.857 -0.270 0.466
0.0001 0.236 0.033
Zinc 1.000 -0.363 0.232
0.106 0.311
RS -1.000 0.316
0.162
Protein 1.000
21. ……Results and Discussion
The positive correlation indicates:
Nutritional quality traits are linked and is possible to enhance one
trait while increasing on the other
The positive correlations observed in this study have also been
reported in other related studies in the world
Positive protein and minerals relationships are possibly due to:
enzyme cofactor requirements during protein formation
since micronutrients acts as metallic activators.
22. ……Results and Discussion
Dendogram showing similarity coefficients of At a 80 % similarity
combined quality traits at Njoro site
coefficient:
4 cluster groups
Similarity
73.64 delineated
composed of 4
82.43
wheat groupings of
91.21
wheat in Kenya.
Groups I, II, III and
100.00
1 2 6 3 10 5 9 7 4 21 8 17 15 11 18 19 16 14 20 12 13
IV
Have different end
Observations
use
23. Conclusion and Recommendations
Great variation in different wheat nutritional parameters
attributed to the different cultivars
Observed values for protein and mineral contents suggest the
potential for improving the nutritive health of the population.
This can contribute greatly to sustaining national development
efforts.
Healthy population always leads to a prosperous Nation
Some cultivars can be used as parents for nutritional breeding
26. Njoro – Site Kenya
Njoro
e
- 2- 3
– 5-
- 1-, 0-
- 1-3
4-
Environmental descriptors of Njoro site
Trial site Alt. Soil type Annual Mean maximum Mean minimum
masl Rainfal (mm) Temperature (0C) Temperature (0C)
Njoro (NPBRC) 2300 Fluvisols 1200 28 16.8
(Return
27. Figure: Analysis of wheat accessions for minerals using Atomic Absorption Spectrophotometer
(Shimadzu Model AA- 6300, Tokyo-Japan). (Return)
28. Table : Twenty one accessions of wheat (Return)
Variety Variety Variety
Kongoni Chozi Kwale
Mbuni Chiriku Nyangumi
Kulungu Ngamia KSRR I
Tembo K. Heroe KSRR II
Njoro BwII Duma KSRR III
Paka Mbega KSRR IV
Fahari Popo KM 14