International Research Journal of Plant Science (ISSN: 2141-5447) Vol. 2(10) pp. 305-310, October, 2011
Available online http://www.interesjournals.org/IRJPS
Copyright © 2011 International Research Journals
Full length Research Paper
Diversity and agronomic potential of barley
(Hordeum vulgare L.) landraces under variable
production system in Ethiopia
Kemelew Muhe1 and Alemayehu Assefa2
1
Ghent University, Faculty of Science, Kwintensberg 54, Ghent 9000, Belgium and College of Agriculture and
Veterinary Medicine, Wollo University, P.O Box 1145, Dessie, Ethiopia.
2
Ethiopian Institute of Agricultural Research, Holetta Agricultural Research Center, P.O.Box 2003. Addis Ababa. Ethiopia.
Accepted 28 September, 2011
Study on the genetic diversity and agronomic potential of 181 Ethiopian barely landraces revealed that
the diversity among the tested barley landraces was sufficient to made selection for high yield and early
maturity. Clustering analysis resulted in ten statistically significant different (P<5%) clusters with high
intercluster Euclidian distance. The intracluster Euclidian distances of some clusters were relatively
large, implying that landraces within each of these clusters were variable for the traits considered. The
intra cluster coefficient of variation for plant height, grain-filling period and thousand grain weight were
fairly large for all clusters, signifying that selection among landraces within a cluster would be
responsive. The highest yielding clusters contained eighty-eight promising landraces for grain yield,
thousand-grain weight, taller plant height and longer grain filling period, whereas landraces included in
low yielding clusters were distinguished for being late maturing and short plant height. Systematic
exploitation of both intra and inter cluster variability among barley landraces was an important task in
the future barley breeding programs aimed at stabilizing barley productivity in areas with unpredictable
rainfall pattern during the belg season in Ethiopia.
Keywords: Barley, landraces, diversity, intercluster, Euclidean distance and cluster, Hordeum vulgare L.
INTRODUCTION
Barely is an important food crop in the highland parts of
Ethiopia. Landraces represent over 90% of the barley
cultivation in Ethiopia (Tanto et al., 2010). It is the crop
that matures early and bridging the critical food shortage
occurs in September. Ethiopia is the centre of barley
diversity for barley (Hordeum vulgare), and plenty of
landraces adapted to different barely growing agroecologies of Ethiopian are available (Negassa, 1985b).
Barley is cultivated from 1400 to 4000 m a.s.l., and it has
adapted to specific sets of agro-ecological and
microclimatic conditions throughout the country (Asfaw,
2000). The diversity of landrace increase parallel to an
*Corresponding Author E-mail: kemelewmuhe2001@yahoo.com
altitude increase, and the maximum diversity is attained
at moderate altitude, 2,460 m a.s.l. (Tanto et al., 2010).
Though landraces don’t show clustering on the basis of
regions of origin, the presence of high morphological
variation within regions and altitudes particularly above
2000 m a.s.l. is also mentioned (Abebe et al., 2010).
Ethiopian barley landraces have useful traits, especially
for resistance to diseases, such as powdery mildew
(Negassa, 1985a), barley yellow dwarf virus, net blotch,
scald, and loose smut (Qualset, 1975). Other useful
characteristics of Ethiopian barleys include high tillering
capacity; tolerance to marginal soil conditions, barley
shoot fly, aphids and frost; vigorous plant establishment
and quick grain filling period (Hailu and Fekadu, 1991).
Despite the immense variability and agronomic potential
the Ethiopian barley landraces have, development of high
306 Int. Res. J. Plant Sci.
yielding barley varieties suitable for low moisture areas
has not been progressive. Thus, it was important to study
the potential of the available barley landraces and
document information, and based on strategic utilization,
collection and introduction of barley genetic resources
would be designed.
MATERIALS AND METHODS
In present study, 181 barley landraces representing
Shewa and Wollo collections collected from the Institute
of Biodiversity conservation, Ethiopian were purified
using pure line selection and evaluated between 1995 to
1996 at two locations Ankober and Kotu. Ankober is
located on the eastern escarpment of the Ethiopian
highlands with a latitude and longitude of 9°34′N 39°54′E
and an elevation of 3000 m a.s.l while Kotu is located at
the eastern edge of the Ethiopian highlands at an
elevations of 2800 m a.s.l with a latitude of 10° 1' 0 N and
a longitude of 39°17'60E. The study areas are
characterized by cool climate and unpredictable short
rainfall of 300-450mm distributed from February to May,
hereafter named as belg production system. The AgroEcology of the study areas is sub moist (SM2) with
temperatures in the range of 2.21-28.30C. The soil in the
study area is classified as clay loam. Five blocks of nonreplicated augmented design in which thirty-six landraces
were assigned in each block, and the local check,
Kesselie was placed at the interval of five plots per block.
Each plots (1m2) was drilled at the seed rate of 85kg/ha
of barely and fertilized by 50/100 kg/ha Urea/DAP. Data
on days to heading (DH), days to maturity (DMT), grain
filling period (GFP = DMT-DH), thousand-grain weigh
(TSW) and grain yield (GY) were recorded on plot basis,
whereas plant height (PHT) was recorded on randomly
selected ten plants and averaged to make plot data
value. The data were transformed using Z-scores and
used for hierarchical cluster analysis using betweengroups linkage method and interval squared euclidean
distance (D2) analysis in SPSS16 statistical software.
One-way analysis of variances between ten clusters and
descriptive statistics of the traits were done using the
same statistical software. Taking X = mean grain yield of
all landraces within a given cluster, Y= mean grain yield
of Kesselie, and the grain yield advantage of landraces in
each cluster as compared (A) was estimated as
.
RESULTS
Diversity of barley landraces
Hierarchical cluster analysis distributed the tested barley
landraces into ten significantly different clusters (Figure
1). Cluster VI, V, X, III and IV contained the highest
number of landraces, respectively, whereas the lowest
number of landraces were included in clusters I, II and VII
(Figure 1 and Table 1). The popular local check barley
cultivar, Kesselie was included in cluster VI. Both inter2
and intra-cluster euclidean distances (D ) were high
(Table 1). Eighty-eight landraces were superior to
Kesselie in most agronomically important traits such as
grain yield. Agronomic superior barley landraces were in
clusters I, III, IX, II, X and V, hereafter named as a high
yielding clusters while cluster VI, IV, VIII and VII , named
as low yielding clusters were characterized by low mean
grain yield and 1000-grain weight (Table 3). Relatively
high intracluster distances in cluster X, V, VI and III
(Table 1), and coefficients of variations for grain filling
period, plant height and thousand-grain weight were
observed in all clusters (Table 2). Height intracluster
range and coefficients of variation were observed for
plant height, grain-filling period and thousand-grain
weight. Grain-filling period and plant height showed high
intracluster coefficients of variation in all clusters except
cluster I. Taking the mean values of Kesselie as a
reference, landraces in high yielding cluster groups gave
an average grain yield, plant height and thousand-grain
weight advantage of 49, 8 and 5%, respectively. In
contrast, the average plant height, thousand-grain weight
and grain yield of landraces in low yielding clusters were
decreased by 10, 10, 8 and 29% (Table 3). Analysis of
variance between clusters showed significant difference
(P < 5%) for days to heading, maturity, grain filling period,
plant height, thousand-grain weight and grain yield (Table
4). High yielding cluster were positively associated with
early flowering, medium plant height, long grain filling
period and thousand-grain weight whereas the low
yielding clusters counterparts contained landraces with
characterized by late to heading, maturity and short plant
height (Table 3).
DISCUSSIONS
Hierarchical clustering analysis of 181 landraces results
in ten clusters, containing landraces with contrasting
expression of agronomic traits. Based on the agronomic
merit of each clusters, the ten clusters in turn re-classified
into high and low yielding cluster groups (Table 3).The
maximum intercluster distances between pair of clusters
from high and low yielding clusters, indicating that barley
landraces included in those clusters are variable for the
traits considered. Moreover, having high intracluster
distances and coefficient of variation are good indicators
for the presence of variability among the barley landraces
within each cluster. The result is supported by earlier
studies (Asfaw, 1989; Demissie and Bjornstad, 1997;
Muhe and Assefa 307
Figure 1. Dendrogram of 181 food Ethiopian barely landrace using Hierarchical analysis, between –groups linkage methods Roman numbers in
the root indicating the cluster number
2
Table 1. Dissimilarity (intracluster along and intercluster above the diagonal) matrix using euclidean distance (D ) for 181 barley Ethiopian landraces
Cluster number
I
II
III
IV
V
VI
VII
VIII
IX
X
Landrace per cluster
I
198.40
II
679.43
205.7
III
276.22
403.39
509.1
IV
1582.27
902.89
1306.19
391.8
V
1067.03
387.63
790.98
515.28
701.3
VI
1353.67
674.27
1077.60
228.64
286.65
498.2
VII
1986.44
1307.10
1710.37
404.23
919.49
632.86
230.4
VIII
1809.46
1130.10
1533.39
227.22
742.49
455.86
177.02
291.32
IX
474.61
204.90
198.61
1107.77
592.51
879.15
1511.98
1334.98
257.2
2
2
23
21
33
42
4
14
9
X
894.89
215.47
618.83
687.43
172.17
458.81
1091.65
914.65
420.35
832.7
31
308 Int. Res. J. Plant Sci.
Table 2. Intraclusters descriptive statistics of 181 barley landraces within each cluster, Ethiopia
Cluster
I
II
III
IV
V
VI
VII
VIII
IX
X
Parameters
Mean
Standard deviation
Coefficient of variation %
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
Mean
Standard deviation
Coefficient of variation%
Range
DHE
84
1.98
2.36
6.0
89.9
4.06
4.52
11.0
90.6
3.13
3.45
8.0
95.5
4.96
5.19
17.00
90.1
4.13
4.58
14.0
92.8
4.05
4.36
14.0
97.6
2.61
2.67
6.00
97.2
2.48
2.55
6.00
87.8
4.65
5.3
13.00
90.5
3.87
4.28
14.00
DMT
122
2.11
1.73
2.0
127
3.19
2.51
9.0
128
3.13
2.45
7.0
129
2.26
1.75
9.00
127
3.26
2.57
9.0
129
2.12
1.64
9.0
129
0
0
0.00
129
0.58
0.45
2.00
127
3.07
2.42
9.00
128
2.87
2.24
9.00
GFP
38
2.18
5.74
14.0
37.1
3.91
10.54
14.0
37
5.29
14.3
14.0
33.5
3.71
11.07
14.00
37.3
3.45
9.25
16.0
35.9
3.72
10.36
13.0
31.4
2.61
8.31
6.00
32
2.63
8.22
6.00
38.9
3.93
10.1
13.00
37.5
3.42
9.12
16.00
PHT
71
2.98
4.2
4.0
70.8
8.15
11.51
32.0
69.2
5.63
8.14
15.0
60.8
7.78
12.8
31.00
69
6.94
10.06
32.0
66.2
7.69
11.62
10.4
52.2
5.76
11.03
13.00
56.3
4.21
7.48
12.00
75.5
6.77
8.97
25.00
71.7
7.82
10.91
29.00
TGW
44.8
2.89
6.45
6.2
37.8
2.88
7.62
11.0
39
2.59
6.64
7.2
36.1
2.43
6.73
7.20
37.9
2.66
7.02
13.4
37.1
2.3
6.2
31.0
33.2
1.47
4.43
3.60
33.9
4.47
13.19
12.00
40.1
2.45
6.11
10.80
38.9
2.72
6.99
10.80
GY
2634
54.9
2.08
72.0
1898
46.2
2.43
150.0
2242
72.9
3.25
182.0
1051
64.4
6.13
221.00
1567
58.2
3.71
206.0
1280
70.8
5.53
230.0
662
40.2
6.07
104.00
883
63.3
7.17
172.00
2063
50.7
2.46
147.00
1728
44
2.55
157.00
Muhe and Assefa 309
√
Table 3. Mean cluster values of the studied traits of 181 barley landraces, Ethiopia
Clusters™
I
III
IX
II
X
V
Kesselie
VI
IV
DF
84,00
90,60
87,82
89,87
90,54
90,15
92,00
92,83
95,46
DMT
122,00
127,60
126,76
127,00
128,00
127,41
129,00
128,76
128,92
GFP
38,00
37,00
38,94
37,13
37,46
37,26
37,00
35,93
33,46
PHT (cm)
71,00
69,20
75,53
70,78
71,66
69,02
66,00
66,17
60,85
TGW
44,80
38,96
40,07
37,83
38,89
37,86
38,00
37,12
36,09
GY (kg/ha)
2634,00
2241,80
2062,71
1898,00
1728,31
1567,02
1358,82
1280,41
1051,85
VIII
97,17
129,17
32,00
56,33
33,93
833,33
VII
97,60
129,00
31,40
52,20
33,20
662,40
¥
A
93,84
64,98
51,80
39,09
27,19
14,80
0,00
-5,77
22,59
38,68
51,25
¥ = grain yield advantage of landraces in each cluster compared to the mean of the popular local check
barely cultivar, Kesselie
™ = Clusters above and below Kesselie are considered as high and low yielding cluster groups
respectively
√
Days to heading (DHE), Days to maturity (DMT), grain filling period (GFP), plant height (PHT), thousandgrain weight (TGW) and grain yield (GY kg/ha).
Table 4. Analysis of variance for traits of ten clusters from181 barely landraces, Ethiopia
Mean Square
Days
to
heading
Days
to
maturity
Grain
filling
period
Plant
height
1000-seed
weight
Grain yield
kg/ha
142.674
Clusters
Degree of
Mean
freedom
Square
9
16.306
Degree of
freedom
171
F
Sig.
8.750
0.000
16.219
9
7.591
171
2.136
0.029
74.674
9
13,021
171
5,735
0.000
590.299
9
52,088
171
0,000
57.722
9
7.535
171
11,33
3
7.661
3042106.619
9
3225.446
171
Abebe et al., 2010; Tanto et al., 2010). High inter-and
intracluster distances indicate that barley landraces in
each clusters are variable, and selection of landraces
both within and between clusters may be bringing about
high genetic gain for the characters considered.
Intercrossing of landraces from clusters with high inter
cluster euclidean distance would produce highly
segregating population for days to heading, maturity,
943.1
59
0.000
0.000
grain filling period, plant height, thousand-grain weight
and grain yield. Landraces in high yielding clusters are
distinguished by early flowering, long grain-filling period,
medium plant high and high thousand-grain weight as
opposed to their low yielding clusters containing late
heading, short plant height and lower thousand-grain
weight. Relatively early heading and maturing landraces
produced higher yield and thousand–grain weight during
310 Int. Res. J. Plant Sci.
the belg barley production system of Ethiopia. Landraces
with taller plant height give better grain yield in
unpredictable rainfall cropping season. This finding is
supported by Acevedo et al. (1991), who reported that tall
barley genotypes are yielded better in low-rainfall
Mediterranean areas. The positive contribution of plant
height with grain yield was also mentioned in barely
(Alam et al., 2007).
Our finding indicates that the variability among Ethiopian
barley landraces is high and sufficient to make selection
for the traits of interest. The presence of a high level of
diversity in Ethiopian barleys has been very much
discussed (Abebe et al., 2010). Earlier studies on the
diversity of Ethiopian barley shows that most of the
variation is due to differences among characters and only
a relatively small fraction due to differences between
regions , and almost all characters are considerably
influenced by altitude within the regions (Engels,1994).
The presence of high morphological variation within
regions and at relatively higher altitude indicates the need
for strategic collection and evaluation of Ethiopian barley
landraces. In general ,because of environmental factors
on the observed morphological variation future
germplasm collection should consider to explore wide
geographical and climatic differences within the country
CONCLUSION
Analysis of genetic diversity is an important component of
barley improvement, and helps to select potential
parental materials for hybridization and developing
recombinant inbred lines. The variability among the
tested 181 barley landraces is sufficient to make
systematic evaluation of landraces for the development of
improved barley varieties suitable for barley producing
areas during the belg season in Ethiopia. Moreover,
landraces from both clusters have been maintained for
further hybridization, development of lodging resistant
and high yielding varieties suitable for high rainfall
receiving areas in Ethiopia. Barley landraces from
clusters I, III, IX, II, X and V are potential donor parents
in breeding for early maturity and high yielding, whereas
short plant height and late maturing counterparts from
VI, IV, VIII and VII can be used as donor parent in
breeding for dwarf, late maturing and high yielding
varieties.
ACKNOWLEDGEMENTS
I gratefully acknowledge the Amhara regional
government for financially supporting this research
project. The technical assistances in field crops
improvement of Debire Birhan Agricultural Research
Center deserve sincere gratitude for making field follow
up the experiment.
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