沙漠研究 22-1, 57 -60 (2012 )"ICAL 1 / DT X"

Journal of Arid Land Studies－Refereed Paper－

Phenotypic Diversity Analysis for Salinity Tolerance ofTunisian Barley Populations (Hordeum vulgare L.)
Hanen SBEI*1), Zied HAMMAMI1), Youssef TRIFA1), Sonia HAMZA1) and Moncef HARRABI1)
Abstract: Salinity is one of the major constraints limiting the yield of barley (Hordeum vulgare L.) in Tunisia especially local barley.
During 2010, a total of one hundred and twenty accessions collected from four regions were evaluated in a field conditions in twocontrasting environments; rain fed and irrigated with high water salinity respectively using an augmented design model. In rain fed
conditions, PCA discriminate the local barley according to their end use; Souihli and Arbi landraces as fodder barley and Ardhaoui
landraces as food and feed. In salinity conditions, Ardhaoui population originally collected from low altitude (Zarzis, Medenine andBen Guerden) is a salt tolerant landrace and display differential mechanisms for salt tolerance. Zarzis and Medenine landraces
displayed a high biomass and high seed number suggesting that tolerance is due to an efficient seed translocation. The Ben Guerden
landrace displayed a high harvest index and early flowering date suggesting that the tolerance is due to maintenance of low floral
abortion. These results are prerequisite for developing tolerant varieties by crossing the best accessions possessing a good biomass
and high fertility with accessions showing a high harvest index.
Key Words: Barley, Diversity, Evaluation, Landrace, Salinity

1. Introduction
Tunisia is essentially represented by arid and semi arid
regions characterized by variable winter rainfall. The intra
and inter-annual irregularity of rainfall led to the use of saline
water for supplemental irrigation. Salt water concentration indams and wells are 2 to 6 gr/l and 4 to 7 g/l respectively. In
some cases water in wells can reach 10 gr/l salt concentrations
especially in the South of Tunisia. Soil salinity is often the
result of intensive agriculture (irrigation, fertilization, etc.)
poorly controlled, resulting to a cumulative deposit of salts
over years and gradually making land unfit for cultivation(Levigneron et al., 1995). In Tunisia, it is estimated thatsaline soils cover over 1,800,000 hectares (Slama, 2004).
Barley production in southern Tunisia is insufficient tosatisfy the needs of humans and animals that constitute a majorsocio-activity of the population in the south (El Felah andMedimagh, 2005). Despite the importance of barley as a feedsource, it remains a marginalized crop. In fact, local varietiesthat are well adapted to production systems in this region are
far to satisfy the increased demand for feed and food.
Therefore, to improve the productivity, it is necessary to search
adaptation of barley accessions to salinity and exploit theavailable genetic variation for its introgression in cultivatedvarieties.
The objective of this study was to identify from a collectionof 120 barley accessions the most tolerant genotypes to salinity
after analysis of their agronomic performance in rain fed andirrigated field conditions with high water salinity.

2. Materials and Methods
2.1. Experimental Materials
A collection of one hundred and twenty barley accessions(Hordeum vulgare L. ssp. vulgare) collected in 2008 fromfourteen localities of four provinces of Tunisia (Kairouan,Gabes, Medenine and Mahdia) by the National Gene Bankwas used (Table 1).
2.2. Experimental sites
All of accessions were sown in the field with twocontrasting environments: South (Medenine) and North ofTunisia (Mateur) on December 5 and 22, 2009 respectively.
The trial was conducted in mixed model augmented design
with six blocks and five modern cultivars as checks. Each
accession was sown in a square meter area (1 × 1 m) i.e. 5 lines
spaced 25 cm. Barley sown in site of Medenine is irrigatedwith saline water with a drip system. The water irrigation
contains 6 gr/l of salt (8.06 ms/cm).
2.3. Agromorphological analysis
Barley plants have been monitored at three development
stages: at 2 nodes, anthesis and maturity. The phenotypic* Corresponding Author: sbeihanen@yahoo.fr
Laboratory of cereal breeding National Institute of Agriculture at Tunisia, City Mahrajene, Menzah 1082 Tunisia
1) Institut National Agronomique de Tunisie: 43 Avenue Charles Nicolle 1082 Tunis, Tunisie

Table 1. Provinces, Regions, GPS coordinates, number of barley accessions and given name by farmers.
Name ofpopulationNumber ofaccessions

Provinces

Regions

Longitude

Latitude

Altitude (m)Kairouan

Nadour38° 03’ N

10° 08’ E

114.9

10 Arbi

Kairouan

ElGfai36°05’ N

10° 14’ E

73

10 Arbi

KairouanGabes

Sisseb36° 00’ N
M enzel hbib 34° 19’ N

10° 14’ E
9° 70’ E51
69-72

10 Arbi
10 Safra (2 row)

Gabes

Elmzaraa

33° 88’ N

9° 73’ E

33-35

7 Ardhao ui

Gabes
Gabes
Gabes

SoukraToujaneM areth

34° 01’ N
33° 69’ N
33° 63’ N

9° 66’ E
9° 98’ E
10° 05’ E37126124

3 Ardhaoui
8 Ardhaoui
2 Ardhaoui

M edenine

M edenine

33° 60’ N

10° 40’ E

8 to 112 Ardhaoui

M edenine

Zarzis33° 40’ N

11° 08’ E-1.76

7 Ardhaoui

M edenine
Gabes

Ben Guerden 10° 08’ N
M atmata
33° 21’ N

14° 25’ E
11° 16’ E

1.4
190

6 Ardhaoui
9 Ardhaoui

Gabes

Toujane33° 42’ N

10° 21’ E

164

6 Ardhaoui

M ahdia
M ahdia
M ahdia

Ksas
Boumerdes
Lahkayma

35° 49’ N
35° 27’ N
35° 28’ N

11° 02’ E
10° 43’ E
10° 54’ E

0.2
77
0.4

18 Souihli
4 Souihli
2 Souihli

M ahdia

Chorbene

35° 30’ N

10° 34’ E

50

6 Souihli

evaluation was performed on eleven agronomic parameters:height (H), leaf Area (LA), days to flowering (FD), tiller
number (TN), harvest index (HI), spike number (SN),biological yield (BY), grain number (GN), grain yield (GY),
thousand seeds weight (TSW), percentage of fertile spikelet’s(PFS).
At 2 nodes and anthesis stages, five plants were taken
randomly from each experimental unit to perform the analysis.
Height (cm) is measured for the main axis from the basis oftillering to the end of the spike. The F3 leaf of main axis offive plants was scanned and the measurement of leaf area wascalculated by an application “Mesurim_pro_29_03_10”. For
biomass calculation, each plant was dried for 48 hours at 80°Cand weighted. A random 0.25 m was used for measurementof yield and yield components. Spikes and straw were driedfor 48 hours at 80°C.
2.4. Statistical analyses
Error variance was based on variance of the checks
between plots and the values were adjusted regarding fixedmodel using SAS software V9.0.

Table 2. Descriptive Statistical Analysis for yield components in twosites of experiment.
SN/m2M in0M ax
M eans
M ateur

572282317248

M edenine

GN/m2TSW

PFS

1054
15006
6007
7259

0,0
78.7
43.5

37.8
100
79.79

40,51

5205

46,70

75.29
77.82

BY
Ton/haGY
Ton/ha

0.3

0.43

20.35
1.34

5.76
2.67
2.85
2.45

0.58

SN: Spike Number, GN: Grain Number, BY: Biological Yield, GY: GrainYield, TSW: Thousand Seed Weight, PFS: Percentage of fertile spikelet’s

tons/ha respectively (DGPA, 2009). Grain yield ranged from0.43 to 0.58 tons/ha. The biological yield varied significantly
from 0.3 to 2 tons/ha with an average of 0.85 tons/ha. Thesefluctuations in grain and biological yields were due to the effectof sites and genotypes.
The average of grain yield at Medenine and Mateur sites
were 2.45 and 2.85 tons/ha respectively with a standard
deviation about 1.7 and 1.5 tons/ha. The grain yield inMedenine was 14% reduced compared to Mateur site. The
SN, BY, GN, and spikelet’s fertility were reduced to 21.7; 34.5;
28.3 and 18.9% respectively while the grain filling inMedenine was better than in Mateur ( more than 13.2%)

3. Results and Discussion
3.1. Yield variation
The average grain yield of both sites was 2.57 tons/ha(Table 2). This performance was better than the national
average yield in 2009 and 2008 which was about 0.75 and 0.8

3.2. Variance analysis
Results obtained from mixed model analysis indicatedsignificant differences between accessions for ten and six traits
among eleven for Medenine and Mateur sites respectively(table 3). Significant differences in Medenine sites forTable 3. Variance analysis estimates for 2 sites Medenine andMateur of eleven quantitative traits.
TraitsM edenine

M ateurHLA

118.54047 ** 122.1055 **287783.38 ns 126562.8 *FDTNBY

165.97*27.2879*
5.7413 *7.668 **
26741.814 * 40665.4 ns

SNGY

8.9852 **33675.59 *17593.7 ns
79316.37 **HI0.342**0.147 ns

PFS
TSN

8.985 **
6.15 **

17.73 *
4944.23 ns

TSW

59.14 *

25.15 ns

H: Height, LA: Leaf Area, FD: Days to flowering, TN: Tiller Number, BY:Biological Yield, SN: Spike Number, GY: Grain Yield, HI: Harvest Index,
PFS: Percentage of fertile Spikelet’s, TSN: Total Spikelet’s Number andTSW: Thousand Seeds Weight.
*, ** difference significant at P= 0.05 level and P=0.01 respectively; ns=
no significant

Fig. 1. Principal component analysis in rain fed site: Accessions
distribution according to the origin of collect.
: Population Arbi
: Population Safra: Population Souihli: Population Ardhaouiheight, flowering date, tiller number, spike number, harvestindex, biological yield, grain yield, percentage of fertile
spikelet’s total spikelet’s number and thousand seeds weight
were observed. No significant difference for leaf area. Only
six criteria presented significant differences between
accessions in Mateur site (H, LA, FD, TN, GY and PFS).
3.3. Principal component analysis
The Principal Component Analysis (PCA) based on all thevariables was used for discrimination between genotypes. In
the environment of Mateur, PCA represented 70% ofvariability (Fig. 1). The parameters; biological yield, grain
yield, spike number and height explained 39% of thevariability whereas PCA2 was influenced by leaf area, Tiller
number, flowering date and fertile spike with 31% ofvariability.
This PCA separated the accessions according to their enduse; i) The Ardhaoui landrace originated from the South isdestinated for feed and food barley and is divided in twosubgroups. First subgroub was characterized by their aptitude
for seed production instead of biomass (Mareth, zarzis,Medenine). The second subgroup was known for theirprecocity, dwarfness, and weak leaf area (Ben Guerden,Alamette, Soukra) because they were naturally selected fortheir adaptation to drought (Ould MED Mahmoud et al., 2009;Hamza et al., 2004). In Menzel Hbib regions, farmers use
also the two rowed type barley population called Safra and it’salso feed and food barley. ii) The accessions of Center andLittoral called respectively Arbi and Souihli landraces are
fodder barley and characterized by tall straw, high leaf area,Fig. 2. Principal component analysis for Medenine site: Accessions
distribution according to the origin of collect.
: Population Arbi: Population Safra: Population Souihli: Population Ardhaouihigh tiller number and late heading date.
At the environment of Medenine, PCA showed that PCA 1and PCA 2 axis explained 77 % of the total variability (Fig. 2).
Biological yield, grain yield, seed number, harvest index andprecocity expressed by flowering date are the best
discriminating parameters for the PCA1 axis that explained
58 % of the total variability. The axis PCA 2 represents 19 %of the total variability and it is influenced by leaf area andheight.
The PCA could distinguish 3 groups, two of them in theright side which suggest good adaptation to salinity as shownby a good yield. The first group (in the upper part) iscomposed essentially of Ardahoui landraces collected from
Zarzis and Medenine that have an altitude less than 1.76 m and
8 to 11 m respectively and characterized by high salinity soilconcentration. At Medenine environment, these accessions
maintained high grain yield. Therefore, maintenance of good
grain yield and a high seed number in high salt soil
concentration could be a mechanism of tolerance to salinity.
The second group in composed by Ksas and Ben Guerdenaccessions (altitude 0.2 and 1.4 m respectively) that wasmoderately salt sensitive accessions.
The accessions
collected from Ben Guerden were characterized by highharvest index and early heading date. Therefore precocity
and a conservation of fertile spikelet’s resulting in rapid seedtranslocation and high harvest index would contribute tosalinity tolerance. In salinity conditions, population originallycollected from low altitude (less than 11 m) was a salt tolerant
population. This result confirms the result of the evaluation
for salt tolerance in pots of eight Tunisian accessions by
Cheikh M’Hamed et al. (2008).
The third group is composed by Arbi population. This
population was salt sensitive barley and could be cultivatedonly in non salt soil (North and Center of Tunisia) as folder
destination.

4. Conclusion
Current study detected high phenotypic variation in barleyaccessions among regions suggested that Tunisian barleylandraces strongly influenced by environmental factors andacquired a natural adaptation. The degrees of variation ofcharacters differ with regions from where the accessions arecollected.
This work is a preliminary study towards the identificationof mechanisms of tolerance to salinity of local barley.
Different mechanisms of Souihli and Ardhaoui landraces wereobserved which suggest that this material could be used inbreeding programs by crossing the best genotypes possessing agood biomass and high fertility with accessions showing a highharvest index.

ReferencesOuld MeD Mahmoud M.A., Bel Hadj Salah H., Harrabi M.,
Hamza S. (2009): Comportement agro-physiologique desorges (Hordeum vulgare) tunisiennes vis a vis du stresshydrique en conditions contrôlées. Revue de l’Institut
Nationale d’Agriculture de Tunisie, 24 (2) : 34-38.
Cheikh M’hamed H., Abdellaoui R., Kadri K., Ben Naceur M.,
Bel Hadj S. (2008): Evaluation de la tolerance au stress salinde quelques accessions d’orge (Hordeum vulgare L.)
cultivées en Tunisie: approche physiologique. Sciences etTechnologie C, 28: 30 -37.
El Felah M., Medimagh S. (2005): Food barley in Tunisia. In
Grando S. and Gormez H. eds., Food Barley: Importance,Uses and Local Knowledge. Proceedings of theInternational Workshop on Food Barley Improvement.
ICARDA, 29-35.
GDAP (2009): Personal communication with Director ofGeneral Direction of Agriculture production, Ministry ofAgriculture and Hydraulics Ressources, Tunisia.
Hamza S., W Ben Hmida., Rebai A., Harrabi M. (2004):
SSR-based genetic diversity assessment among Tunisian
winter barley and relationship with morphological traits.
Euphytica, 135:107-118.
Levigneron A., Lopez F., Varisuyt G., Berthomieu P.,
Casse-Delbart F. (1995): Les plantes faces au stress salin.
Cahier d’Agriculture, 4:263-273.
Slama F. (2004): La salinité et la production végétale. Centrede Publication Universitaire Tunis, 163 p.