رسالة السيد السيد الشاوى

Assessment of Water Stress Tolerance in Selected

Barley Genotypes

BY

El-Sayed El-Sayed Abd-Allah EL-Shawy

B.Sc. Agric. (Agronomy) Kafr El-Sheikh, Tanta University (2003)

M.Sc. Agric. (Agronomy), Fac. Agric., Kafr El-Sheikh University (2009)

Submitted in Partial Fulfillment of

The Requirements for the Degree of

Doctor Philosophy

IN

Agriculture sciences (Agronomy)

Department 0f Agronomy

Faculty of Agriculture

Tanta University

1434 A.H

2013 A.D

Tanta University


Department of Agronomy


Barley Genotypes

BY

El-Sayed El-Sayed Abd-Allah EL-Shawy


M.Sc. Agric. (Agronomy), Fac. Agric., Kafr El-Sheikh University (2009)

Thesis

Submitted in partial fulfillment of the requirements for the degree

Of

Doctor Philosophy

IN

Agriculture sciences (Agronomy)

SUPERVISING COMMITTEE

Prof. Dr. El- Sayed Hamid El-Seidy

Prof. and Head of Agronomy Dept., Fac., of Agric., Tanta University

Prof. Dr. Khairy Abdel-Aziz Amer

Head of Research and Chief Researcher of Barley Research Dept ,.

Field Crops Research Institute, ARC.

Dr. Amgad Abd El-Ghaffar El-Gammaal Lecturer of Agronomy Dept. Fac. of Agric., Tanta University

1434 A.H

2013 A.D

Tanta University


Department of

Agronomy

APPROVAL SHEET

:Title of Thesis


Barley Genotypes

Submitted to: Department of Agronomy,

Faculty of Agriculture, Tanta University,

Tanta, Egypt.

BY: El-Sayed El-Sayed Abd-Allah EL-Shawy


M.Sc. Agric. (Agronomy), Fac. Agric., Kafrelsheikh University (2009)

For: the Degree of Ph.D. in (Agronomy)

The dissertation work has been assessed and approved by:

Prof. Dr. Ahmed Abo El-Naga Kandil .............................................................

Prof. of Crop Science, Agronomy Dept.,

Fac. of Agric., Mansoura Univ.

Prof. Dr. Ramdan Aly El-Refaey ......

Prof. of Crop Science, Agronomy Dept.,

Fac. of Agric., Tanta University.

Prof. Dr. El-Sayed Hamid El-Seidy .....

Head of Agronomy Dept. and Prof. of Crop Science,

Fac. of Agric., Tanta University.

Prof. Dr. Khairy Abdel-Aziz Amer .... Head of Research and Chief Researcher of Barley Research Dept.,

Field Crops Research Institute, ARC.

Department of Agronomy

Faculty of Agriculture, Tanta University.

Date: / /2012

ACKNOWLEDGEMENT

First of all, all thanks are to God for his gifts.

Sincere appreciation and deep gratitude are due to my supervisor Prof, Dr.

El-Sayed H. El-Seidy, Professor and head of Agronomy Department, Faculty of

Agriculture, Tanta University, for his supervision, encouragement, scientific advice

and my deepest thanks are also for his sincere cooperation in reading and correcting

this manuscript ,besides his helpful discussion.

Sincere appreciation and deep gratitude are due to Prof, Dr. . Khairy Abdel-

Aziz Amer team leader of Sakha barley Research Program. Field Crops Res.

Institute, ARC, Egypt. For his sincere help in providing of the research materials,

scientific advices and, criticism throughout the experimentation.

Sincere thanks are due to,Dr Amgad Abd El-Ghaffar El-Gammaal Lecturer

of Agronomy Department, Faculty of Agriculture, Tanta University, for his

scientific advices , his great help in correct this manuscript, guidance and fruitful

supervision. Special thanks and deep gratitude to Dr. Alaa Ali Attia Eid, Researcher in

barley department. Sakha Agriculture Research station. Agric. Res. Center. For his

scientific advices, encouragement throughout this study the hard work and long

hours that were devoted to prepare the manuscript.

Great appreciation and respect to the staff member of the Agronomy Dept.,

Faculty of Agriculture, Tanta University for the academic part study.

Thanks to all staff members of Barley Res. Dept., especially at Sakha for their

help and providing facilities.

Finally, I am deeply grateful to my family; Father (R.I.P.), Mother,

Brothers, Sister, my Wife and Friends for their continuous inspiration,

encouragement and patience throughout this work.

ABSTRACT

Assessment of Water Stress Tolerance in Selected Barley

Genotypes

ABSTRACT

To evaluate some barley (Hordeum Vulgare L.) varieties and sixteen

breeding lines for high yield potential and stable performance under two

irrigation treatments (non-stressed and stressed), dry matter accumulation, leaf

area index, crop growth rate, net assimilation rate, relative growth rate, relative

water content, total chlorophyll content, days to maturity, plant height, spike

length, number of spike/m2, water use efficiency and grain indices such as 1000-

grain weight, number of grains per spike, grain yield, biological yield in addition

to seven stress tolerance indices were evaluated (STI, YI, YSI, MP, GMP, Yr,

DSI)* during two successive seasons 2009/10 and 2010/11 at Sakha Res.

Station. All the studied characteristics were significantly affected by water stress

at both growing seasons, except for water use efficiency and total chlorophyll

content. High positive correlation was found between each of the biological

yield and grain and all of the attributes of the number of days to maturity, plant

height, spike length, number of spikes/m2, number of grains/spike, 1000-grain

weight. There were significant differences for all the seven indices among the

genotypes. Grain yield under normal condition (GYp) was highly significantly

correlated with grain yields under stressed (GYs) conditions. Correlation

analysis between drought tolerance indices and yield components showed that

grain yield under irrigated condition was positively correlated with MP, STI,

GMP and YI. While, yield under stress condition (GYs) was positively

correlated with YSI, MP, STI, GMP and YI and negatively correlated with Yr

and DSI. Genotypes were significantly different for their yield under stress and

non-stress conditions . L4 and L8 had the heaviest grains and the highest values

of WUE under both conditions compared with Giza 126 (check variety), as well

as possessed high values of MP, YSI, STI, GMP and YI and DSI less than one,

and low values of Yr, revealing that these genotypes were more tolerant to water

stress and more desirable genotypes for both stress and non-stress conditions.

*Abbreviations: STI stress tolerance index, YI yield index, YSI yield stability

index, MP mean productivity, GMP geometrical mean productivity, Yr yield

reduction ratio, DSI stress susceptibility index. GYs grain yield under drought

condition, GYp grain yield under normal condition, WUE water use efficiency.

TABLE OF CONTENTS

1. Introduction 1

2. Review of literature. 3

2.1. Effect of water stress on growth analysis. 3

2.2 Effect of water stress conditions on barley agronomic traits. 5 2.3. Drought susceptibility indices. 13

2.4. Interaction effect. 17

3. Materials and methods. 22

3.1. Experimental design. 23

3.2. Data recorded. 24

3.2.1. Earliness characters. 24

3.2.2. Growth analysis. 24

3.2.3. Physiological traits. 26

3.2.4. Yield and its components. 26

3.2.5. Drought tolerance indices. 27

3.2.6. Correlation coefficients. 28

3.2.7. Reduction ratio 28

4. Results and discussion. 29

4.1. Growth analysis and attributes. 29

4.1.1. Dry matter accumulation (DM). 29 4.1.2. Leaf area index (LAI). 33

4.1.3. Crop growth rate (CGR). 36

4.1.4. Net assimilation rate (NAR). 39

4.1.5. Relative growth rate (RGR). 42

4.1.6. Relative water content (RWC). 44

4.1.7. Total chlorophyll content. 47

4.1.8. Days to heading. 51

4.1.9. Days to maturity. 52

4.1.10. Plant height. 55

4.2. yield and yield components: 57

4.2.1. Spike length. 57

4.2.2. Spikes number/m2. 59

4.2.3. Grains number per spike. 61

4.2.4. 1000-grain weight. 63

4.2.5. Biological yield. 65

4.2.6. Grain yield. 67

4.2.7. Water use efficiency (WUE). 69

4.3. Simple correlation coefficients between grain yield and the other

studied characteristics overall the two growing seasons. 72

4.4. Tolerance indices of 20 barley genotypes under stress and non-

stress conditions. 73

5- Summary. 77

6- References. 85

7- Arabic summary. .

LIST OF TABLES

Table (1): Soil analysis of the experimental field at Sakha Agricultural

Research Station at 2009/10 and 2010/11 seasons. 22

Table (2): Amount of supplied water in m3fed.

-1 at different barley critical

growth stages, rainfall amount and total water supplied at

2009/10 and 2010/11 Seasons.

22

Table (3): Maximum, minimum temperature, average relative humidity

and rainfall during the growing seasons of barley crop at Sakha

Agricultural Research Station, (ARC), Egypt.

23

Table (4): Name, pedigree and origin of the twenty barley genotypes. 24

Table (5): Means of dry matter accumulation (DM) as affected by

irrigation treatments and barley genotypes as well as its

interaction at three growth stages in both growing seasons. 30

Table (6): Means of leaf area index (LAI) as affected by irrigation

treatments and barley genotypes as well as its interaction at

three growth stages in both growing seasons.

33

Table (7): Means of crop growth rate (CGR) as affected by irrigation


three growth stages in both growing seasons. 36

Table (8): Means of net assimilation rate (NAR) as affected by irrigation



39

Table (9): Means of net assimilation rate (NAR) as affected by irrigation



Table (10): Means of relative water content (RWC) as affected by

irrigation treatments and barley genotypes as well as its

interaction at three growth stages in both growing seasons.

45

Table (11): Means of total chlorophyll content as affected by irrigation



Table (12): Means of heading date as affected by irrigation treatments and

barley genotypes as well as its interaction at three growth

stages in both growing seasons.

51

Table (13): Means of maturity date as affected by irrigation treatments and



53

Table (14): Means of plant height as affected by irrigation treatments and


stages in both growing seasons. 55

Table (15): Means of spike length as affected by irrigation treatments and



58

Table (16): Means of spikes number/m2 as affected by irrigation



59

Table (17): Means of grains number per spike as affected by irrigation



62

Table (18): Means of 1000-grain weight as affected by irrigation



64

Table (19): Means of biological yield as affected by irrigation treatments

and barley genotypes as well as its interaction at three growth


66

Table (20): Means of grain yield as affected by irrigation treatments and



67

Table (21): Grain yield status of barley genotypes in drought trail

compared to local variety (Giza126) in 2009-2010 and 2010-

2011 seasons.

70

Table (22): Means of water use efficiency as affected by irrigation



71

Table (23): Simple correlation coefficients between grain yield and the

other studied characteristics overall the two growing seasons. 72

Table (24): Tolerance indices of 20 barley genotypes under stress and

non-stress conditions. 74

Table (25): Simple correlation coefficients (r) between grain yield under

normal Yp, grain yield under stressed Ys conditions and

tolerance indices overall the two growing seasons.

75

INTRODUCTION

- 1 -

1. INTRODUCTION

Barley (Hordeum vulgare, L.) is the main crop grown in a large scale in

rainfed areas of Egypt. It was adapted long time ago to survive and grow

satisfactorily under adverse conditions, i.e. drought, low soil fertility, saline soil,

high or low temperature and moisture stress. It is considered one of the most

suitable crops that can be grown over a wide range of soil variability and under

many adverse condition crops.

The major use of barley in Egypt as well as in the most developing

countries for animal and poultry feeding. There is renewed interest in using the

crop as human food in (North Africa) and in malting industry, the increased

consumption of animal product especially for sheep and goats has resulted in a

sharp demand on barley. Because of the increasing interest in using barley for

human consumption, hull-less barley has been considered as an ideal type to

achieve this goal.

Barley is the dominant cereal crop grown in North West Coast and North

Sinai in Egypt. It is grown also in the new reclaimed lands. Most of these lands

are suffering from water shortage and low soil fertility. Development of barley

cultivars having the ability to grow well under drought and the other

environmental stresses is needed. An additional avenue is cultivation of the early

maturing barley cultivars before cotton, to support the wheat production in

Egypt for bread making to overcome the gab between wheat consumption and

wheat production. Because barley production areas are located in different

environments, developing stable barley cultivars is one of the main objectives

for barley breeders. In this respect, Katta et al. (2009) and Amer (2010)

reported the possibility of developing some barley genotypes combining high

yield potential under a wide range of environmental stresses.

The rainfed areas in Egypt cover about 120,000 hectares in the North West

Coast and about 40.000 hectares in North-Sinai (Noaman, 2008). Farming

systems of these populations are livestock mainly sheep with barley as their

INTRODUCTION

- 2 -

main annual crop for fodder and bread-making. Anyway, improving barley

production depends on developing new genotypes having high yield potentiality

under stress conditions, expanding barley production areas, and identifying the

proper crop management.

Drought is a major abiotic stress that severely affects barley production

worldwide. Therefore, research on crop management practices that enhances

drought tolerance and plant growth when water supply is limited has become

increasingly essential. Barley germplasm is a treasure trove of useful genes and

provides rich sources of genetic variation for crop improvement.

The ability of a cultivar to produce high and satisfactory yield over a wide

range of stress and non-stress environments is very important. Finlay (1968)

believed that stability over environments and yield potential are more or less

independent of each other. Blum (1979) suggested that one method of breeding

for increased performance under water stressed conditions might be to breed for

superior yield under optimum conditions on the assumption that the best lines

would also perform well under sub optimum conditions. Sojka et al. (1981)

pointed out that a high yield base line that allows a cultivar to do well over a

range of environments does not imply drought resistance. They defined drought

tolerance as the ability to minimize yield loss in the absence of soil water

availability. The ideal situation would be to have a highly stable genotype with

high yield potential (Finlay & Wilkinson, 1963; Smith, 1982).

The combination of high yield stability and high relative yield under

drought has been proposed as useful selection criterion for characterizing

genotypic performance under varying degree of water stress (Pinter et al.,

1990). Ahmad et al. (1999) found combination of drought susceptibility index

(measure of yield stability) vs. relative yield useful in identifying genotypes with

yield potential and relatively stable yield performance under different moisture

environments. The objective of the present study, therefore, was to screen barley

genotypes with high yield potential under water stress conditions.

Review of Literature

3

2-REVIEW OF LITERATURE

Review of literature in the present study is classified

according to the topics of the study into the following main

headings:

2.1. Effect of water stress on growth analysis:

Spitters and Kramer (1985) discussed changes in relative

growth rate (RGR) with plant ontogeny in spring wheat genotypes and

found that the genetic variance of RGR decreased much less with time

than RGR itself. They added that late flowering cultivars had higher

RGR.

Rama Rao (1986) estimated relative growth rate (RGR) and

net assimilation rat (NAR) between 30-45 days, 45-75 days and 75-

105 days in wheat. He stated that RGR is one of important parameter

to assess the performance of crop growth particularly a early stages.

Menshawy (2000) reported that the relative growth rate

(RGR) and net assimilation rat (NAR) declined with time in all

genotypes of wheat under studies.

Tarrad et al. (2002) showed that water stress led to decrease

most of barley morphological, physiological and studied characters.

Flag leaf area was decreased in the stress treatment by 45.4% and its

dray weight by 32.2% compared to control. Leaf relative water

content (RWC) was decreased by water deficit depending on stress

period and plant growth stage.

Alam et al. (2003) investigated the effect of irrigation on

growth of wheat (cv. Kanchan). They were observed that all studied

parameters differed significantly (p < 0.05) due to both treatment (no

irrigation and irrigated). All growing parameters i.e. leaf area index


4

(1.37 and 3.73 at 60 and 75 days, respectively), crop growth rate

(282.10 and 158.99 mg day-1

plant-1

at 60-75 and 75-90 days,

respectively) ant relative growth rate (0.108 and 0.021 mg mg-1

at 60-

75 and 75-90 days, respectively) were exhibited the value when

irrigated thrice and corresponding the lowest obtained from the

control treatment (no irrigation).

Shahen (2005) investigated the response of four barley

genotypes (Giza123, Giza126, Giza2000 and a breeding line

(MAF102/Volla//WW319xGiza119)) to moisture stress at the

different growth stages (one irrigation was applied at sowing; two

irrigation were applied, the first at sowing and the other after 45 days

from sowing and three irrigations were applied at sowing, after 45 and

75 days from sowing). The increases in growth analysis attributes

(LA, RGR, CGR and NAR) were higher than can for by adding the

increase in growth due to moisture.

Rana et al. (2006). Reported that the photosynthesis per unit

leaf area was not initially reduced by salinity, particularly in the more-

tolerant Line 455, as the chlorophyll per unit area was higher in saline

than non-saline conditions (the leaves were narrower, the cells were

smaller, and so the chloroplast density was greater).That the hormonal

control of cell division and differentiation is affected by salinity is

clear from the appearance of leaves: leaves are smaller in area but

greener, i.e. the density of chloroplasts has increased, indicating that

cell size and shape has changed. Leaves have a higher specific leaf

weight (higher dry weight: area ratio) which means that their

transpiration efficiency is higher (more carbon fixed per water lost), a

feature that is common in plants adapted to both dry or saline soil.


5

Jazy et al. (2007) evaluated the effect of irrigation regimes on

growth indices of three bread wheat (Triticum aestivum L.) genotypes.

Irrigation treatments (irrigation after 70 (I1), 90 (I2) and 110 (I3) mm

and three wheat genotypes (Mahdavy, Ghods and Roshan-Backcross).

The I1 and I2 did not differ significantly for all growth indices and total

dry matter. Delay in irrigation from I2 to I3 significantly reduced

growth indices and total dry matter. Trend of changes in Leaf Area

Index (LAI), Total Dry Matter (TDM), Net Assimilation Rate (NAR)

and Crop Growth Rate (CGR) were similar in the I1 and I2 in all

samplings, delay in irrigation from I2 to I3 reduced all growth indices.

Mollah and Paul (2008) studied the growth attributes of four

varieties of barley (BARI Barley-1, BARI Barley-2, BHL-3, BL-1) in

relation to different soil moisture regimes. Three levels of irrigation

treatments were adopted, viz., rain fed (I0), 20 mm irrigation (I1) and

40 mm irrigation (I2) at every 30 days interval for three times during

the growing period. For growth analysis, plants were harvested at 10

days intervals and the first harvest was taken at 20 days. Total dry

matter (TDM), leaf area index (LAI) and crop growth rate (CGR)

were increased with increasing number of irrigations. Net assimilation

rate (NAR) fluctuated, but in most of the cases, it was highest and

lowest in the I2 treatment at the first and last harvest. With few

exceptions, I0 treatment had the highest and lowest leaf area ratio

(LAR) at the first and last harvest, respectively.

2.2. Effect of water stress conditions on barley agronomic

traits:

Michael (1978).Water use efficiency (WUE) is often

considered an important parameter of yield under stress and even as a


6

component of crop drought tolerance. As well as water utilization

efficiency is a useful measure in evaluating irrigation practice;

particularly under deficit irrigation technique, where irrigation water

is searched. Such measure illustrated the crop performance as

irrigation water was applied water that require for crop yield

potentiality.

Ceccarelli (1987) reported that, water deficit during the early

stage of plant development induces a reduction in spikelets primordia,

while water deficit late in the plant development increases death of the

flower and the entire spikelet. The number of grains per spike

(fertility) depends on the water availability during the early vegetative

phase and during the shooting stage. If water deficit occurs after the

flowering stage, it induces a decrease of grain weight and thus its

yield

Dutt (1988) found that reduction in grain yield of four barley

cultivars under stress conditions was due to the decrease in number of

the filled grain/plant and 1000-grain weight.

EL-Hawary (2000) studied the effects of three water

depletion of available soil water on yield and yield components in

some wheat varieties. He found that the average values of number of

spikes/m2, number of grains/spike and grain yield/fed were

significantly decreased with increasing depletion of available soil

water.

Mohammed (2001) investigated the genetic behavior of 45

wheat genotypes under normal and water stress conditions, he found

that the mean performance of both parental wheat genotypes and cross


7

combinations were lower under stress condition as compared with

normal conditions.

Abd El-Wahab (2002) studied the effect of soil moisture

stress on yield and yield components in bread wheat, he found that

grain yield produced under different depletion levels was decreased

with increasing the soil water stress, while the mean of grain yield had

different values for the tested varieties. Irrigation treatments

significantly resulted larger number of spikes per m2 and grains per

spike, while number of spikes per m2 and grains per spike were highly

significantly affected by the studied wheat varieties. Increasing soil

moisture depletion tended to reduce kernel weight, which was

significantly influenced by the wheat varieties.

Nabipour et al. (2002) evaluated eight wheat cultivars for

drought resistance. They found that, 1000-kernel weight, number of

kernels/spike, grain yield and plant height were decreased with

drought. Number of spikes per plant was the least affected, while

number of kernels per spike was the most affected under water stress

condition.

Moursi (2003) conducted two field experiments, using six

bread wheat genotypes to study grain yield and its attributes and

drought susceptibility index. Grain yield and its attributes decreased as

affected by increasing soil moisture stress.

Bayoumi (2004) studied plant height (PH), grain yield and its

components and drought susceptibility index under water stress and

normal irrigation treatments. The mean squares due to genotypes,

parents and crosses were highly significant for all traits, indicating the


8

presence of wide diversity among the parental materials and the 15

F1s crosses under normal and water stress conditions.

Mohamed (2004) employed six parents of bread wheat and

their F1s under water stress and normal conditions. The most

genotypes under water stress condition were decreased plant height

and grain yield and its attributes than the normal one. Most of the

studied genotypes had decreased the number of spikes/plant and

kernels/spike, 100-kernel weight and grain yield/plant under stress

than non-stress condition.

Farhat (2005) studied days to heading, days to maturity,

plant height and grain yield and its components in six bread wheat

parents in diallel crosses. He found that water stress treatment

decreased the means of all studied characters for all genotypes.

Mahmoud et al. (2006) indicated that plant height, number

of spikes plant, 100 kernel weight, and grain yield per plant for four F1

crosses derived from four barley lines as testers and six barley

genotypes (lines), under two locations (normal and stress conditions)

were decreased significantly under stress conditions.

Bagheri and Abad (2007) found that number of spikes and

grains per plot were decreased significantly under stress, grain weight

was less sensitive to drought stress. The biological and grain yields

were decreased under drought stress. The biological yield differences

were related to low plant height, leaf area and tiller number; the grain

yield differences were caused by reduction in ears per plant and grains

per ear.


9

Kamel et al. (2008) determined the effect of full and deficit

irrigation on soil salinity, yield and water use efficiency of barley

(Hordeum vulgar,L.).They found that, no significant difference were

observed in grain yield, dray matter and 1000kernels weight,

kernels/spike and spike per m2 form the comparison between full

irrigation and deficit irrigation treatments.

Klar and Santos (2008) studied some physiological

parameters on six barley cultivars (Borema, Lagoa, BRS-180, BRS-

195, EMB-128 and BRS-225), with application of water deficit cycles

on different plant phenological phases. Leaf diffusive resistance to

water vapour (Rs), relative water content (RWC) and leaf water

potential (LWP) of leaves were used for evaluating drought tolerance.

EMB-128 showed better adaptation to stress based only on the relation

LWP x RWC.

Santos et al. (2008) evaluated drought tolerance in 6 barley

cultivars (Borema, Lagoa, BRS-180, BRS-195, EMB-128 and BRS-

225). Plants irrigated until harvesting, water stress starting from 45

days after sowing (DAS) and water stress starting from 65 DAS. All

the cultivars exhibited adaptation to water stress. However, EMB-128

and BRS-180 had the greatest and lowest potential for drought

tolerance, respectively.

Sorin et al. (2008) evaluated the drought tolerance of 23

Romanian and foreign winter barley cultivars using different

screening techniques: excised leaf water loss, leaf relative water

content, and pollen deformation rate after osmotic stress using

polyethylene glycol. Considering the appreciations of the four used

techniques, the highest drought tolerance was presented by cultivars:


10

Salemer, Secura, Compact, Adi, Dana. An pronounced sensibility for

hydric stress was observed in cultivars: Precoce, Orizont, Andrei,

Pfyner, Manitou.

Szira et al. (2008) discussed various drought stress

experiments (hydroponics and in soil) in which the plant tolerance was

studied at different developmental stages. Tests were performed in the

germination, seedling and adult plant stages on the parental lines of

ve well-known barley-mapping populations. The results suggest that

drought tolerance is a stage-specic trait and changes during the life

cycle. The effect of drought stress depended not only on the duration

and intensity of water deciency but also on the developmental phase

in which it began. To induce the same type of stress and to obtain

comparable tolerance information from the replications, it is

recommended that drought stress should be induced at the same

growth stage. Correlations between the traits, commonly associated

with improved drought resistance (high relative water content under

stress, proline accumulation and osmoregulation) with stress tolerance

indexes, are also presented, while the advantages and disadvantages of

the most frequently used screening methods are discussed.

Ali (2009) The assessed included the combination comprising of

2 barely genotypes ( Jesto and Sahrawe) and applied 50 mm. water

irrigation in each of the five irrigation schedules ( 0, 50,100,150 and

200 mm ) of cumulative pan evaporation, (CPE). The aim of the study

was to assess the potentiality of two barely genotypes under water

stress condition. The highest value of grain yield, 1000 grain weight

and water use efficiency of both cultivars in both seasons, as

compared with the other levels of water irrigation. 20 to 40 % of water


11

irrigation could be conserved for growing barley under arid

environment of Saudi Arabia.

Samarah el al. (2009) investigated the growth performance

and grain yield of four barley cultivars under late-terminal drought

stress under both glasshouse and eld conditions. At grain lling, four

barley cultivars (Rum, ACSAD176, Athroh and Yarmouk) were

exposed to three watering treatments: (1) well-watered [soil

maintained at 75 % eld capacity (FC)], (2) mild drought stress at 50

% FC, (3) severe drought stress at 25 % FC in the glasshouse

experiment and (1) well-watered (irrigated once a week), (2) mild

drought (irrigated once every 2 weeks), (3) severe drought (non-

irrigated; rainfed) in the eld. As drought stress severity increased,

gross photosynthetic rate, water potential, plant height, grain lling

duration, spike number per plant, grain number per spike, 1000-grain

weight, straw yield, grain yield and harvest index decreased.

Refay (2010) evaluated the response of four barley genotypes

viz., (Jesto, Giza121, Giza123 and local variety) to water irrigation

schedules viz., (70, 100, and 180 mm of cumulative pan evaporation,

(CPE), plus traditional water irrigation method used by many farmers

(weekly irrigation). Results obtained showed that no particular trend

was observed in the most studied growth parameters, more or less

values were accompanying with decreasing in water irrigation.

However, among the selected four barley genotypes, Giza121 ranked

all other tested genotypes in most of growth, yield and yield

component characters. No significant differences due to interactions

effect were found in most of studied parameters. Noticeable, rapid

decrease pronounced true in yield and yield component characters as

well as yield parameters associated with low water irrigation.


12

Vaezi el al. (2010) tested in a two-year experiment, 11 barley

genotypes from ICARDA and one landrace from Iran under optimum

and drought stress conditions. Phenological and physiological traits

such as relative water content (RWC), plant height (PLH), days to

heading (DHE), days to maturity (DMA) and seed indexes such as

1000-grain weight (TGW), number of grain per spike (G/S) and grain

yield (GY) were evaluated. Variations were observed in DHE, DMA,

G/S, TGW, PLH and RWC. DHE and DMA were the phenological

traits that most influenced yield during water stress conditions.

Negative correlation was observed under water stress between yield,

DHE, and DMA under drought stress. The average reduction in yield

caused by drought stress was 28.05%. Under drought stress condition,

TGW, G/S and RWC correlated positively with yield, while under

both stress conditions, the correlation of yield and PLH was lower

than other correlations.

Mollah and Paul (2011) studied the influence of soil

moisture and variety on yield and yield components of barley

(Hordeum vulgare L.). Three levels of irrigation treatments (0, 20 and

40 mm water as I0, I1 and I2 respectively) were adopted at every 30

days interval for three times during the growing period. Plant height,

tiller number, spikelet number, grain number, 100-grain weight and

grain yield were observed highest in the I2 (40 mm irrigation water).

But the highest water use efficiency (WUE) was observed in the I0 (no

irrigation). Lower WUE with higher soil moisture status was due to

proportionately more increase in evapotranspiration than the increase

in seed yield.

Soliman et al. (2011) determined the response of the yield of

three barley hulled cultivars (Giza 123, Giza 124 and Giza 125) to two


13

irrigation amounts (high amount equivalent to 2250 m 3 /fed and low

amount equivalent to 1500 m 3 /fed) and their water use efficiency.

The results indicated that the three studied barley cultivars were

significantly different. Giza 123 was superior in plant height, number

of spikes/m2 and spike length. However, Giza 124 had the highest

value for 1000-grain weight, grain and biological yield. The low

irrigation amount gave the highest yield in the three cultivars. But, the

response of Giza 124 to irrigation treatments was the best, where its

yield was the highest and water use efficiency was the highest. All

yield attributes were highly and significantly correlated to barley

yield. Obtained results stressed on the importance of applying less

irrigation water to the growing crops to maintain the sustainable use of

water and soil resources.

Budakli and Celik (2012) determined the correlations

between grain yield and yield components and to measure the direct

and indirect effects of yield components on grain yield in barley by

using correlation coefficient and path analysis methods, respectively.

Agronomic traits such as grain yield, plant height, spike length, kernel

number per spike, kernel weight per spike, spike number per m2

,

harvest index and 1000-kernel weight were determined. The data from

two years were combined. Correlation analyses indicated that the

grain yield was positively and significantly associated with all the

yield components except 1000-kernel weight. The highest correlation

coefficients were found between grain yield and kernel number per

spike (r = +0.406), and between grain yield and harvest index (r =

+0.474).

2.3. Drought susceptibility indices:

Fisher and Maurer (1978) used cultivars representing


14

several species [Triticum aestivum, Triticum durum, triticale and

barley, Hordium vulgare]. They found that the SI value varied

according to the crop species and within bread wheat cultivars. The

average SI of 8 tall bread wheat cultivars was 0.83 as compared to

1.013 to short cultivars, whereas the SI value was 1.055 for durum

wheat varieties, 1.21 for triticale and 0.95 for barley. This means that

the tall bread wheat cvs were more drought resistance than short bread

cvs, durum cvs and triticale which was more susceptibility than others.

Farhat (2005) found in six wheat genotypes and their hybrids

at normal and water stress conditions that, Sakha 93 had the lowest SI

followed by Giza 164 followed by Sakha 8, while Chinese spring had

the highest SI followed by Sakha 61 followed by Sakha 94. Therefore,

parents with relatively low SI values seem to be more tolerant to water

stress than that of SI > 1. SI for hybrids ranged from 0.13 for Sakha 93

x Sakha 94 to 3.8 for Sakha 94 x Chinese spring.

Nazari and Pakniyat (2010) tested sixteen barley genotypes

under two different irrigation regimes (non-stressed and stressed).

Plants were subjected to moisture stress at flowering period till

maturity. Six drought tolerance indices, stress tolerance index (STI),

stress tolerance (TOL), stress susceptibility index (SSI), yield

reduction ratio (Yr), mean productivity (MP) and geometric mean

productivity (GMP) were used. The indices were adjusted based on

grain yield under stress (Ys) and non-stress (Yp) conditions. There

were significant differences for all criteria among the genotypes. The

significant and positive correlations of Yp with (MP, GMP and STI)

and Ys with (MP, GMP and STI), as well as, significant negative

correlation of SSI and TOL under stress environment, revealed that

the selection could be conducted for high values of MP, GMP and STI


15

under both conditions and low values of SSI and TOL under stress

condition. The correlation coefficient indicated that STI, MP and

GMP are the best criteria for selection of high yielding genotypes

under both stress and non-stress conditions.

Naghaii and Asgharipour (2011) studied the effects of late

season drought stress on agronomic characteristics of 20 barley

genotypes. Results showed that genotypes were caused significant

differences in grain yield, biological yield, one-thousand grains

weight, ear number/m2, grain number/spike, spike length, grain filling

period, harvest index and plant height at both stressful and normal

environment. As it was expected, drought caused a significant

reduction in all the agronomic traits. The correlation between traits

showed the most positive significant correlation in stress and normal

conditions was observed between grain yield versus one-thousand

grain weight, and between grain yield versus harvest index,

respectively. Also, results showed that the three indicators of drought

tolerance STI, GMP, MP had most significant positive correlation

with yield in both conditions. Evaluation indicators of drought

tolerance of STI, GMP and MP showed that, genotype No. 20 (M-82-

14) can be represented as superior genotype under late season drought

and normal conditions.

Abdi et al. (2012) studied the effect of drought stress on

quantitative attributes of 40 figures and lines, bread wheat was tested

in two environments, normal and drought stress. Results of the

variance analysis showed that for both normal and drought stress

conditions, differences among the genotypes, in terms of most

characteristics were significant. Correlations between different

drought resistance indexes and grain yield from both normal and stress


16

conditions were positive and significant. However, correlations of SSI

and TOL indexes with yield in normal condition were positive and

significant but results were negative and significant with yield in

stress condition. Calculations done with the various drought resistance

indexes indicated that 3 indexes; those of Mean Productivity (MP),

Geometrical Mean (GMP) and Stress Tolerance Index (STI) were the

most important indexes for the identification of a genotypes

resistance to drought.

Khokhar el al. (2012) evaluated twelve barley genotypes

based on different selection methods under drought and irrigated

conditions. Drought stress reduced the yield of some genotypes while

others were tolerant to drought, suggesting genetic variability in this

material for drought tolerance. The results of a correlation matrix

revealed highly significant associations between Grain Yield and

Mean Productivity, Stress Tolerance Index, Geometric Mean

Productivity and Yield Index under irrigated conditions while, the

Mean Productivity, Yield Stability Index, Stress Tolerance Index,

Geometric Mean Productivity and Yield Index had a high response

under stressed condition. Based on a principal component analysis,

Geometric Mean Productivity, Mean Productivity and Stress

Tolerance Index were considered to be the best parameters for

selection of drought-tolerant genotypes.

Muhammad et al. (2012) evaluated twelve barley genotypes

based on different selection methods under drought and irrigated

conditions. Drought stress reduced the yield of some genotypes, while

others were tolerant to drought, suggesting genetic variability in this

material for drought tolerance. The results of a correlation matrix

revealed highly significant associations between Grain Yield and


17

Mean Productivity, Stress Tolerance Index, Geometric Mean

Productivity and Yield Index under irrigated conditions while, the

Mean Productivity, Yield Stability Index, Stress Tolerance Index,

Geometric Mean Productivity and Yield Index had a high response

under stressed condition. Based on a principal component analysis,

Geometric Mean Productivity, Mean Productivity and Stress

Tolerance Index were considered to be the best parameters for

selection of drought-tolerant genotypes. The 2-row barley genotypes

B-07023 and B-07021 performed good in yield response under

drought conditions and were also more stable under stress conditions.

Furthermore, drought stress reduced the yield of some genotypes,

while others were tolerant to drought, suggesting genetic variability in

this material for drought tolerance.

2.4. Interaction effect:

Mugabe and Nyakatawa (2000) found that interaction effect

between deficit irrigation and six wheat genotypes were highly

significant for grain yield and insignificant for days to heading, days

to maturity, number of ears/m2, plant height and 1000-kernel weight.

Sadek (2000) observed that interaction between wheat

cultivars and irrigation treatment had significant effect for number of

spikes/m2 and grain yield.

El-Ganbeehy (2001) showed that the interaction effect

between irrigation treatment and wheat and barley cultivars had highly

significant for number of kernels/spike and insignificant effect for

grain yield, spikes/m2, plant height and days to heading.

Mahgoub and Sayed (2001) observed that interaction effect

between wheat cultivars and irrigation levels were significant for


18

number of kernels/spike, while it were insignificant for1000-kerenl

weight and plant height.

Tawfelis et al. (2001) in upper Egypt, stated that the

interaction between water stress and wheat genotypes were significant

for days to heading, days to maturity, plant height, number of

spikes/m2, grain yield, straw yield, number of grains/spike, 1000-grain

weight and harvest index.

Abo-Warda (2002) indicated that interaction between wheat

genotypes and irrigation treatments had significant effect on grain

yield, number of spikes/m2, number of grains/spike and 1000-grain

weight.

El-Banna et al. (2002) indicated that interaction between

wheat genotypes and irrigation treatments had insignificant effect on

plant height and 1000-grain weight. In the first season, interaction

effects for days to heading and number of spikes/m2 were

insignificant. While, for flag leaf area, number of grains/spike and

grain yield were significant.

Hassaan (2003) observed significant differences for the

interaction between bread wheat genotypes and drought stress for

plant height, number of kernels/spike and grain yield.

Hefnawy and Wahba (2003) indicated that, interaction

between irrigation and wheat cultivars had significant effects on

spikes/m2, 1000-kernel weight, number of kernels/spike, grain yield,

straw yield and harvest index.

Kheiralla et al. (2004) revealed that the interaction between

water stress and wheat genotypes were highly significant effects on

1000-kernel weight and grain yield.


19

Moussa and Abdel-Maksoud (2004) found that, interaction

effect between irrigation and wheat cultivars was insignificant for

number of spikes/m2, number of grains/spike, 1000-grain weight,

straw and grain yields.

Abd El-Ati and Zaki (2006) found that, interaction between

wheat cultivars and irrigation treatment had highly significant effects

on days to heading, days to maturity, plant height, number of

spikes/m2, number of kernels/spike, 1000-kernel weight and grain and

straw yields.

El-Afandy (2006) found that, interaction between wheat

cultivars and irrigation treatment had highly significant effects on

plant height, grain and straw yields and protein percentage. While, the

interaction effect was insignificant for spikes/m2, number of

kernels/spike and harvest index.

Khalil et al. (2006) indicated that, interaction between

cultivars and irrigation treatments had highly significant effects on

plant height and grain yield, while it was insignificant for

kernels/spike and 1000-kernel weight.

Mamnouie el al. (2006) observed significant interaction

between barley varieties and irrigation treatments only for number of

spikes/m2 and grain yield. Meanwhile, the effects were insignificant

for grain number per spike, 1000-grain weight, total chlorophyll

content (SPAD values) and Proline content.

Menshawy et al. (2006) found that, interaction between

cultivars and number of irrigation had highly significant effect on

number of days to heading and maturity, plant height, and grain and

straw yields in one season and on 1000-kernel weight. Meanwhile, the

effects were insignificant for number of spikes/m2.


20

Samarah el al. (2009) found that, irrigation treatments

barley cultivars interaction effect was signicant for grain number per

spike, 1000-grain weight, straw yield and grain yield. While, the

interaction effect was insignificant for heading date, plant height and

spike number per plant.

Khayatnezhad el al. (2010) revealed that the interaction

between water stress and wheat genotypes were highly significant

effects on plant height and grain yield. Meanwhile, the effects were

insignificant for of spikes number, spike length, 1000-grain weight

and biological yield.

Refay (2010) revealed that the interaction between water

stress and barley varieties was clearly assigned only in 1000-grain

weight and number of grains per spike in both seasons. While, it was

insignificant for number of days to heading and maturity, plant height,

spike length, number of spike/m2, grain yield, biology yield and water

use efficiency.

Mollah and Paul (2011) observed significant interaction of

irrigation barley varieties only for WUE. Meanwhile, the effects

were insignificant for Plant height, tiller number, extrusion length,

spikelet number per plant, plant weight, grain number per plant, 100-

grain weight and grain yield.

Zare el al. (2011) found that, stress barley genotypes

interaction effect was only significant for seeds number per spike.

While, the interaction effect was insignificant for plant height, spike

length, number of spikes per plant, 1000-grain weight, biological yield

and grain yield.

Ali el al. (2012) revealed that, irrigation and cultivar

interaction has significant influence on plant height. While, it was


21

insignificant for total number of tiller pet plant, ear length, peduncle

length, RWC of leaf, the number of days from germination to stem

elongation, from germination to anthesis stage, from germination to

flowering stage and from germination to physiological ripening.

MATERIALS AND METHODS

22

3. MATERIALS AND METHODS

This study was carried out at Agronomy Department, Faculty of

Agriculture, Tanta University. The field experiments were carried out in

the Experimental Farm at Sakha Agricultural Research Station, Kafr El-

Sheikh Governorate, Egypt, during the two successive growing seasons of

2009/10 and 2010/11. The main objective of the present study, therefore,

was to screen twenty barley genotypes with high yield potential under

water stress conditions

Soil samples were randomly taken from the experimental area at a

depth of 0 to 30 cm from soil surface before barley sowing. The soil

properties are shown in Table 1. Water application was mentiored via a

water meter as shown in Table 2.

Table (1): Soil analysis of the Experimental Field at Sakha

Agricultural Research Station at 2009/10 and 2010/11

Seasons.

Determination Sand % Silt % Clay % Texture pH E.C(ds/m)

2009/2010 13.74 24.91 61.35 Clay 7.9 2.1

2010/2011

15.53 23.95 60.52 Clay 8.2 2.9

Table (2): Amount of supplied water in m3fed.

-1 at different barley

critical growth stages, rainfall amount and total water

supplied at 2009/10 and 2010/11 Seasons.

Irrigation

Treatment

Growth

Season

Growth Stages Irrigation

Sowing Tillering Booting Water

(m3)

Rainfall Total (m

3 fed.

-1) mm m

3 fed.

-1

Irrigated 2009/10 550 350 450 1350 28 117.6 1667.6

2010/11 500 325 450 1275 120 504 1779

Stressed 2009/10 550 - - 550 28 117.6 817.6

2010/11 500 - - 500 120 504 1004


23

In the first season, the maximum temperature was high, but the

relative humidity and the total rainfall were low compared with the

second season (Table 3).

Table (3): Maximum, minimum temperature, average relative

humidity and rainfall during the growing seasons of

barley crop at Sakha Agricultural Research Station,

(ARC), Egypt.

Month

Temperature o(C)

Relative humidity (%) Rainfall (mm) 2009/10 2010/11

Max. Min. Max. Min. 2009/10 2010/11 2009/10 2010/11

Dec. 22.72 8.92 16.82 14.75 66.44 80.94 5.80 44.95

Jan. 21.77 7.77 14.73 12.49 71.48 87.74 0.00 28.21

Feb. 23.38 9.19 15.81 13.32 65.11 79.00 22.20 22.40

Mar. 23.92 9.18 18.24 15.09 62.09 77.97 0.00 13.95

Apr. 28.77 11.76 23.40 18.08 68.62 66.77 0.00 10.50

Twenty barley genotypes (2 lines from ICARDA, 14 breeding

lines and three local varieties i.e. Giza 121, Giza 126 and Giza 132 and

Beacher introduced from USA, named Giza 118) were chosen for the

study based on their reputed differences in yield performance under

normal and stress conditions, their names, pedigrees and origin are

presented in Table 4.

3.1. Experimental design:

Giza 126 was the most drought tolerant variety. So, this variety was

used as check compared with the other genotypes. Grains were hand

drilled at the recommended sowing rate of barley in the irrigated land in

Egypt (50 kg fed.-1

). Each genotype was sown in six rows of 3.5 m,

spaced with 20 cm among rows. These experiments were laid out in a

RCBD with four replications. The first experiment was irrigated twice


24

after sowing, at 45 days after sowing at tillering stage and 75 days after

sowing at booting stage (normal condition), while, the second experiment

was given just sowing irrigation only (drought stress condition). Sowing

was done in 15th of November in both seasons. All recommended culture

practices were applied at proper time according to ministry of agriculture

recommended. The preceding crop was cotton in the two seasons.

The test of homogeneity of error was applied, before carrying out the

combined analysis, according to Bartlett (1937). Combined analysis of

variance for each year was carried out according to Snedecor and

Cochran (1967).

Table (4): Name, pedigree and origin of the twenty barley genotypes.

genotypes Pedigree \ Name Origin

Giza 126 BaladiBahteem/SD729-por12762-Bc Egypt

Giza 132 Rihane-05//As46/Aths*2" Aths/ Lignee686 Egypt

Beacher Introduced to Egypt from USA and named Giza-118 USA

Giza 121 Baladi16/Gem Egypt

Line 1 Giza 117/3/ACSAD 618//Aths/Lignee 686 Egypt

Line 2 Giza 117/4/Kenya Research/Belle//As46/Aths*2/3/Arar/19-3//WI2294 Egypt

Line 3 Ssn/Bda//Arar/3/Arabayan-01//CI07117-9/Deir Alla 106 ICARDA

Line 4 ACSAD1182/4/Arr/Esp//Alger/Ceres362-1-1/3/WI/5/ACSAD1180/3/Mari/ Aths*2//M-Att-73-337-1

Egypt

Line 5 Giza 117/4/Kenya Research/Belle//As46/Aths*2/3/Arar/19-3//WI2294 Egypt

Line 6 ACSAD1182/Harmal-02/Salmas/4/Lignee527/NK1272/3/Nacha2//Lignee 640/ Harma-01

Egypt

Line 7 HOR 1657/4/GLORIA-BAR/COME-B//LIGNEE 640//5/G2000 Egypt

Line 8 Lignee 527/Chn-01/Gustoe/5/Alanda-01/4/WI2291/3/Api/CM67//L2966 - 69

ICARDA

Line 9 Alanda//Lignee527/Arar/5/Ager//Api/CM67/3/Cel/WI2269//Ore/4/Hamra-1/6/ Lignee527/NK 1272/3/Nacha 2//Lignee 640/Harma-01

Egypt

Line 10 Giza 119/3/ESCOBA/BRB2//ALELI Egypt

Line 11 Giza 119/4/TOCTE//CEN-B/2*CALI92/3/MARCO/SEN//CARDO Egypt

Line 12 Giza 125/3/ACSAD 618//Aths/Lignee 686 Egypt

Line 13 CC 89/Saico Egypt

Line 14 ACSAD1182/Harmal-02/Salmas/5/ACSAD1182/4/Arr/Esp//Alger/Ceres362-1-1/3/WI

Egypt

Line 15 ACSAD 1182/Harmal-02/Salmas/3/Saico Egypt

Line 16 ACSAD1182/Harmal-02/Salmas/5/ACSAD1182/4/Arr/Esp//Alger/Ceres362-1-1/3/WI

Egypt

3.2. Data recorded:

3.2.1. Earliness Characters :

1-Heading date: Number of days from sowing to 50% of heading for

all plants / plot.


25

2-Maturity date: Number of days from sowing to 50% yellow stage

of maturity for all plants / plot.

3.2.2. Growth Analysis:

Half meter long guarded tillers were randomly taken from the

second inner rows of each plot at 45, 65 and 85 days after sowing to

determine the growth characters. Each sample was separated into stems

and leaves, and then Leaf area (blades area) was measured by Portable

Area Meter (Model LI-3000A). The tillers organs were dried separately in

the electrical air-draft oven at 70oC until constant weight for

determination of whole dry weight.

The growth characters were estimated as follows:-

1- Total dray matter. (g/m2)

2- Crop Growth Rate (CGR): at an instant in time (t) is defined

as the increase of tillers material per unit of time.

CGR was measured according to (Radford, 1967).

2- Relative Growth Rate (RGR): at an instant in time (t) is defined

as the increase of plant material per unit of material present per

unit of time.

g/g/week. ) - (

)e

- e

( RGR

tt

wLogwLog

12

12

RGR was ca lcula ted according to ( Radford, 1967 ) .

3- Net Assimilation Rate (NAR): at an instant in time (t) is

defined as the increase of plant material per unit of material

present per unit of assimilatory material per unit of time.

/week.g/m ) - ( ) - (

)e

- e

( )- ( N.A.R 2

1212

1212

ttAA

ALogALogww

/week.g/m ) - (

)- ( CGR 2

12

12

ttww


26

Where: w1, A1 and w2, A2 respectively refer to dry weight and leaf

area at time (t1) and (t2) in week according to (Radford, 1967).

4- Leaf area index (LAI): it is defined as total area of leaves of

the plants compared with the area of land occupied by the plants

according to Watson (1952).as described by the following

formula:

)(cm area ground Tillers

)(cm / tillersarea Leaf L.A.I

2

2

5- Plant height (cm): ten plants were taken at random from each sub

plot and measured in cm. from the soil surface to the top of the

spike of the main tiller.

3.2.3.Physiological traits:

1- Total chlorophyll content (SPAD value): was determined by

measuring the flag leaf total chlorophyll content by using analytical

apparatus; chlorophyll meter (Model SPAD- 502) Minolta camera

Co. Ltd, Japan.

2- Relative water content (RWC %): It was determined by the

method of Barrs (1968). To determine the relative water content

(RWC), the harvested leaf was cut into 12 cm sections, and

immediately weighed (FW), then sliced into 2 cm sections and

floated on distilled water for 4 hours. The turgid leaf discs were

then rapidly blotted to remove surface water and weighed to

obtain turgid weight (TW). The leaf discs were then oven dried

for 2 hours at 60oC and dry weight (DW) was recorded. RWC

was calculated by the formula:

Where FW = fresh weight of leaf.

DW = dry weight

TW = full turgor.

100..

DWTW

DWFWCWR


27

3-Water use efficiency (WUE):

= 3min applied water irrigationGrowth

kgin yieldGrain (Michael, 1978).

3.2.4. Yield and Its Components:

At harvest time, the central area from each plot was harvested to

determine the following traits:

1. Number of spikes/m: It was estimated by counting all spikes per

square meter.

2. Spike length (cm): ten spikes were selected by random and their

lengths were measured, then average was calculated to express

mean spike length in cm.

3. Number of grains/spike: Average number of grains in ten

randomly chosen spikes was estimated.

1000-grain weight (g): A random sample of 1000-grains was

taken from each plot, hand counted and weighted to record the mean

weight of 1000 grains.

4. Biological yield (kg/fed.): It was recorded from all harvested

plants / plot and converted to kg/fed.

5. Grain yield (kg/fed.): It was recorded from the grains of harvested

plants/plot after threshing and then converted to kg/fed.

3.2.5. Drought tolerance indices:

1- Mean productivity 2

Yp Ys (MP)

(Hossain et al., 1990).

2- Stress tolerance index 2Y

Ys Yp (STI)

p

(Fernandez, 1992).

3- Geometrical mean productivity )()( YsYpGMP 0.5

(Fernandez,1992).

4- Yield index sY

Ys (YI) (Gavuzzi et al., 1997; Lin et al., 1986).

5- Yield stability index p

Ys (YSI)

Y (Bouslama and Schapaugh, 1984).


28

6- Yield reduction ratio p

Ys1 (Yr)

Y (Golestani and Assad, 1998).

Where Ys is the yield of genotype under stress, Yp is the yield

of genotype under irrigated condition, sY s and pY are the mean

yields of all genotypes under stress and non-stress conditions,

respectively.

7- Stress susceptibility index (DSI) = (1-Yd/Yw)/D

(Fischer & Maurer, 1978).

Where Yd = mean yield under drought, Yw = mean yield

under normal condition, and D = environmental stress intensity =

1- (mean yield of all genotypes under drought/mean yield of all

genotypes under irrigated conditions). Lower stress susceptibility

index than unity (DSI 1) means higher stress

sensitivity.

3.2.6. Correlation coefficients:

Estimates of the simple phenotypic correlation coefficients (r) among

all traits for the entry means were calculated according to Kearsey and

Pooni (1996).

3.2.7. Reduction ratio % :

It provides a measure of drought tolerance based on minimization of

loss under stressed conditions compared to irrigated conditions. This

index was calculated from genotype means for each trait using the

generalized flowing formula:

Reduction % = (irrigated - stressed / irrigated) 100.

(Choukan et al., 2006)

RESULTS AND DISCUSSION

- 29 -

4-RESULTS AND DISCUSSION

Several a biotic stresses have a common element, among them,

namely decreased cell water status including water deficit, salinity, and

low temperature. The nomenclature used to describe water deficit stress is

also diverse: drought, water stress, moisture stress and osmotic stress were

used, but these may not be physiologically equivalent (Artlip and

Wisniewski, 2002). Drought tolerance or tolerance in native plant species

is often defined as survival, but in crop species it must be defined in terms

of productivity (Passioura, 1983).

Barley is most sensitive to stress during jointing, booting and

heading. Significant stress during grain filling substantially degrades

barley yield. Grain yield reductions of 14 %, 8 %, and 4 % were measured

for these three respective periods. Considering drought stress before,

during and after heading, yield was reduced the most by stress just before

heading. Thus, to eliminate yield-reducing, plan to irrigate before heading.

Stress prior to or just after flowering reduce yield, the most compared to

stress at other stages. While these yield reduction effects can be alleviated

somewhat if the stress is relieved later in the season, yield recovery from

stress near the flowering stage is lower than recovery from stress in early

vegetative stages (Kirkpatrick et al., 2006).

4.1- Growth analysis and its attributes:

4.1.1-Dry matter accumulation (DM):

The overall means of the effect of irrigation treatments, twenty

barley genotypes and their interactions on DM during three growth stages

are presented in Table (5).

The results in Table (5) indicated that, dry matter (DM) was

significantly affected by water stress. DM was higher in the irrigated

treatment than in the stressed condition. Data indicated that, the


- 30 -

differences among irrigation treatments for DM at different stages were

highly significant, suggesting genetic variability in these materials for

stress and non-stress conditions. In general, DM significantly increased at

normal irrigation than at stress one. Dry matter increased slowly at early

stages of growth, and then increased rapidly with the advancement of plant

age. The cause of rapid increase of DM at the later stages was possibly due

to the development of a considerable number of late tillers, plant height

and leaf area. These results are in harmony with those reported by Shahen

(2005) and Mollah and Paul (2008).

Table 5. Means of dry matter accumulation (DM) as affected by irrigation



Characteristic

Dry matter accumulation (DM) Sample 1 (45 days) Sample 2 (65 days) Sample 3 (85 days)

2009/10 2010/11 2009/10 2010/11 2009/10 2010/11

Main effect of irrigation treatments

Irrigated 635 433 1286 3131 2677 1573

Stressed 591 371 1186 3135 2308 1211

LSD 0.05 2.51 1531 3.03 2545 10.75 2531

Reduction% 7 31 8 31 14 31

Main effect of barley genotypes

Giza 126 640 656 1274 1330 2478 2687

Giza 132 659 679 1315 1379 2626 2709

Beacher 570 560 1158 1198 2384 2528

Giza 121 626 642 1251 1301 2546 2663

L 1 553 566 1158 1200 2307 2421

L 2 610 619 1210 1273 2458 2571

L 3 598 605 1233 1271 2477 2546

L 4 720 755 1388 1480 2753 2909

L 5 660 669 1288 1353 2584 2721

L 6 655 683 1277 1333 2575 2697

L 7 604 610 1218 1250 2466 2548

L 8 674 701 1336 1411 2670 2816

L 9 613 633 1247 1303 2527 2680

L 10 533 548 1149 1198 2375 2481

L 11 627 650 1260 1323 2509 2666

L 12 517 521 1139 1180 2340 2405

L 13 582 599 1211 1255 2416 2507

L 14 606 597 1201 1225 2442 2503

L 15 616 626 1234 1276 2501 2613

L 16 594 552 1167 1163 2414 2462

LSD 0.05 7.92 11.14 9.57 32555 34.00 32517


- 31 -

Cont. Table 5.

Characteristic Dry matter accumulation (DM)

Interaction

genotypes

Sample 1 (45 days) Sample 2 (65 days) Sample 3 (85 days)

2009/10 2010/11 2009/10 2010/11 2009/10 2010/11

Irrigated Stressed Reduction

% Irrigated Stressed

Reduction


Reduction


Reduction


Reduction


Reduction

%

Giza 126 666 615 8 684 628 8 1316 1232 6 1386 1275 8 2590 2366 9 2860 2515 12

Giza 132 689 629 9 730 629 14 1383 1247 10 1506 1252 17 2821 2430 14 2935 2483 15

Beacher 568 571 -1 568 552 3 1195 1121 6 1218 1179 3 2601 2167 17 2695 2362 12

Giza 121 638 613 4 663 621 6 1284 1218 5 1343 1259 6 2750 2343 15 2857 2468 14

L 1 583 522 10 643 488 24 1215 1101 9 1345 1055 22 2444 2170 11 2675 2168 19

L 2 595 624 -5 587 650 -11 1235 1184 4 1277 1170 8 2586 2330 10 2610 2531 3

L 3 641 555 13 713 496 30 1329 1138 14 1463 1078 26 2709 2246 17 2889 2204 24

L 4 725 714 2 717 793 -11 1400 1375 2 1527 1434 6 2909 2597 11 2951 2866 3

L 5 693 628 9 695 644 7 1345 1231 8 1423 1283 10 2789 2380 15 2904 2537 13

L 6 675 636 6 709 658 7 1320 1234 7 1375 1291 6 2756 2394 13 2853 2540 11

L 7 650 557 14 683 536 22 1281 1155 10 1377 1123 18 2665 2267 15 2821 2275 19

L 8 681 667 2 715 687 4 1361 1312 4 1430 1391 3 2827 2513 11 2941 2691 9

L 9 638 588 8 644 621 4 1287 1207 6 1314 1292 2 2736 2318 15 2808 2551 9

L 10 552 513 7 561 534 5 1209 1089 10 1245 1150 8 2558 2192 14 2641 2322 12

L 11 643 611 5 667 633 5 1302 1218 6 1376 1270 8 2701 2316 14 2816 2516 11

L 12 527 507 4 544 498 8 1205 1074 11 1271 1088 14 2510 2170 14 2596 2215 15

L 13 592 571 4 641 558 13 1251 1171 6 1340 1169 13 2573 2259 12 2664 2349 12

L 14 652 561 14 670 523 22 1274 1127 12 1347 1103 18 2665 2220 17 2764 2242 19

L 15 635 597 6 657 595 9 1277 1190 7 1335 1217 9 2693 2309 14 2795 2430 13

L 16 648 541 17 604 500 17 1243 1092 12 1271 1056 17 2652 2175 18 2751 2174 21

LSD 0.05 11.2 -- 15.75 -- 13.53 -- 88.88 -- 48.08 -- 88.88 --


- 32 -

The results clearly showed highly significant differences existed

between barley genotypes in dry matter. Giza 132, L4, L5, L6 and L8 gave

the highest values for DM compared with Giza 126 in the three samples in

both seasons. The increases in growth analysis attributes were higher than

can for by adding the increase in growth due to moisture.

Highly significant interaction between barley genotypes and

irrigation treatments was found in the three samples. In the first sample

Giza 132, L4, L5, L6 and L8 had highest values for DM under both

conditions in the first season, while, Giza 132, L4, L6 and L8 had the

highest values under the irrigation treatment and L2, L4, L5, L6 and L8

had highest values under stress condition. The reduction percentage

ranged from -5% in L2 to 17% in L16 in the first season and -11% in L2

and L4 to 30% in L3 in the second season.

For the second sample, Giza 132, L4, L5 and L8 in the first season

and Giza 132, L3, L4, L5 and L8 in the second season had the highest

values for DM under irrigated treatment, While, Giza 132, L4 and L8

highest in the first season and L4 and L8 in the second season had values

under the stressed treatment compared to Giza 126. The reduction

percentage ranged from 2% in L4 to 17% in L16 in the first season and

ranged from 2% in L9 to 26% in L3 in the second season.

With respect to the third sample, Giza 132, Giza 121, L3, L4, L5,

L6, L7, L8, L9, L11, L14, L15 and L16 under the irrigated treatment in the

first season and Giza 132, L3, L4, L5, and L18 in the second season had

higher values. Giza 132, L4 and L8 in the first season and L3, L4, L5, L6

and L8 in the second season under the stressed treatment had higher values

for DM compared to Giza 126. The reduction percentage ranged from 9%

in Giza 126 to 18% in L16 in the first season and 3% in L2 to 24% in L3

in the second season.


- 33 -

4.1.2- Leaf area index (LAI):

The overall means of the effect of irrigation treatments, twenty

barley genotypes and their interactions on LAI during three growth stages

are presented in Table (6).

Irrigated treatment had higher leaf area index than the stressed one.

LAI was exhibited the highest value under irrigated treatment and

corresponding the lowest value obtained from the stressed treatment. LAI

decreased with decreasing irrigation application, suggested that the leaf

area decreased with increase in water stress.

Table 6. Means of leaf area index (LAI) as affected by irrigation



Characteristic

Leaf area index ( LAI) Sample 1 (45 days) Sample 2 (65 days) Sample 3 (85 days)

2009/10 2010/11 2009/10 2010/11 2009/10 2010/11


Irrigated 6.73 7.93 23.60 23.68 11.69 12.41

Stressed 6.18 7.70 21.92 22.38 9.33 11.76

LSD 0.05 0.07 0.04 0.06 0.09 0.04 ...7

Reduction% 6 3 7 7 20 5

Main effect of barley genotypes Giza 126 7.45 7.86 22.55 22.55 10.71 12.44

Giza 132 7.60 7.97 22.80 22.62 11.09 12.75

Beacher 7.26 7.81 22.09 21.89 9.93 11.68

Giza 121 7.35 7.88 22.73 22.79 10.37 11.92

L 1 7.24 8.10 22.10 22.54 10.09 11.44

L 2 6.92 7.57 22.52 22.76 10.54 12.28

L 3 7.65 8.16 22.74 23.26 10.38 11.74

L 4 8.38 8.62 23.44 24.03 11.34 12.82

L 5 7.96 7.90 23.17 23.82 11.11 12.92

L 6 7.52 7.87 23.01 23.68 10.80 12.39

L 7 6.59 7.20 23.25 24.31 10.11 11.67

L 8 7.65 7.86 23.65 25.05 11.09 12.87

L 9 7.55 7.78 22.25 21.59 10.53 11.88

L 10 7.29 7.58 22.22 21.97 10.43 12.13

L 11 7.13 7.78 22.42 22.74 10.33 12.05

L 12 7.01 7.43 22.89 22.48 10.38 11.94

L 13 8.12 8.10 23.08 22.94 10.61 12.11

L 14 7.16 7.63 22.64 22.56 10.11 11.44

L 15 7.12 7.50 22.94 23.68 10.02 11.59

L 16 7.16 7.72 22.78 23.48 10.24 11.70

LSD 0.05 ..02 0.21 0.25 ..06 0.13 0.18


- 34 -

Cont. Table 6.

Characteristic Leaf area index ( LAI)

Interaction

Genotypes

Sample 1 (45 days) Sample 2 (65 days) Sample 3 (85 days)

2009/10 2010/11 2009/10 2010/11 2009/10 2010/11

Irrigated Stressed Reduction


Reduction


Reduction


Reduction


Reduction


Reduction

%

Giza 126 7.72 7.18 7 7.99 7.72 3 23.52 21.58 8 23.25 21.68 7 11.77 9.66 18 12.56 12.32 2

Giza 132 7.8 7.4 5 8.07 7.87 2 23.65 21.95 7 23.28 21.95 6 12.34 9.84 20 13.11 12.40 5

Beacher 7.56 6.96 8 7.96 7.66 4 22.30 21.89 2 22.32 21.45 4 11.23 8.63 23 12.05 11.31 6

Giza 121 7.64 7.06 8 8.02 7.74 3 22.86 22.61 1 22.88 22.70 1 11.27 9.48 16 12.06 11.78 2

L 1 7.37 7.1 4 8.16 8.03 2 22.65 21.54 5 23.07 22.01 5 11.34 8.84 22 12.02 10.87 10

L 2 7.07 6.76 4 7.64 7.49 2 23.28 21.76 7 23.44 22.08 6 11.84 9.24 22 12.89 11.67 9

L 3 7.86 7.45 5 8.26 8.06 2 23.43 22.05 6 23.82 22.70 5 11.54 9.22 20 12.03 11.45 5

L 4 8.55 8.2 4 8.71 8.54 2 23.85 23.02 3 24.19 23.86 1 12.41 10.28 17 12.98 12.67 2

L 5 8.37 7.55 10 8.11 7.70 5 23.67 22.67 4 24.56 23.08 6 12.18 10.04 18 13.04 12.80 2

L 6 7.81 7.22 8 8.02 7.72 4 23.94 22.08 8 24.94 22.42 10 11.90 9.69 19 12.43 12.35 1

L 7 6.9 6.29 9 7.35 7.05 4 24.31 22.18 9 25.31 23.31 8 11.44 8.78 23 12.29 11.05 10

L 8 7.77 7.53 3 7.92 7.80 2 23.68 23.63 0.2 25.68 24.41 5 12.29 9.89 20 13.13 12.61 4

L 9 7.8 7.31 6 7.91 7.66 3 23.06 21.44 7 22.06 21.12 4 11.65 9.42 19 12.09 11.67 3

L 10 7.73 6.85 11 7.80 7.36 6 23.43 21.00 10 22.43 21.51 4 11.65 9.22 21 12.54 11.72 7

L 11 7.28 6.98 4 7.86 7.71 2 23.80 21.03 12 22.80 22.67 1 11.66 9.00 23 12.60 11.50 9

L 12 7.24 6.77 6 7.55 7.32 3 24.18 21.60 11 23.18 21.78 6 11.58 9.19 21 12.25 11.62 5

L 13 8.13 8.1 0.4 8.11 8.10 0.1 24.18 21.99 9 23.55 22.33 5 11.88 9.33 21 12.63 11.60 8

L 14 7.38 6.94 6 7.74 7.52 3 24.30 20.99 14 23.92 21.20 11 11.38 8.83 22 11.90 10.99 8

L 15 7.16 7.08 1 7.52 7.48 1 23.80 22.09 7 24.30 23.06 5 11.21 8.84 21 11.99 11.19 7

L 16 7.45 6.86 8 7.87 7.57 4 24.17 21.40 11 24.67 22.29 10 11.27 9.22 18 11.85 11.54 3

LSD 0.05 3.01 -- -- -- 0.29 -- 3.00 -- 0.18 -- 3..5 --


- 35 -

Leaf area index reached in a certain value in the second sample and

then declined with plant age in the third sample. The increase of LAI

occurred due to the increase of leaf expansion in the irrigated plants.

Increase in soil moisture resulted in increased turgor pressure in the cells

and turgor forces played a part in the process of leaf expansion. These

results are in agreement with those obtained by Tarrad et al. (2002),

Alam et al. (2003), Shahen (2005), Jazy et al. (2007) and Mollah and

paul (2008).

The results clearly showed highly significant differences existed

between barley genotypes in LAI. These results indicated the different

genetic background of the twenty barley genotypes. L4, L5 and L13 in the

first season and L1, L3, L4 and L13 in the second season gave the highest

values for LAI compared to Giza 126 in the first sample. While in the

second sample, Giza 132, L4, L5, L6, L7, L8, L12, L13 and L15 in the

first season and L3, L4, L5, L6, L7, L8, L13, L15 and L16 had higher

values compared to Giza 126 in the second season. Giza 132, L4, L5 and

L8 gave the highest values in the third sample in both seasons.

The interaction between the irrigated treatments and barley

genotypes had insignificant effect on this criterion in the first sample in

the second season, these results are in agreement with those obtained by

El-Banna et al. (2002). While, highly significant effect was observed in

first sample in the first season and both of second and third samples in

both seasons. In first sample, L4 and L5 under irrigated and L4, L5, L8

and L13 under stress had the highest values. L4, L6, L7, L12, L13, L14

and L16 in the second season had the highest values for LAI under

irrigated treatment, while Giza 132, Beacher, Giza 121, L3, L4, L5, L6,

L7, L8 and L15 gave the highest values under stress. In the third sample

Giza 132, L4, L5 and L8 gave the highest values under irrigation, while

Giza 132, L2, L4, L5, and L8 gave the highest values under both


- 36 -

conditions. These results indicated that, the behavior of these genotypes

differed from environment to another and ranked differently from stress to

normal irrigation in the second and third samples, but in the first sample, it

did not affected by changing environments.

4.1.3-Crop growth rate (CGR):

Crop growth rate of four barley verities and sixteen lines estimated

at two growth intervals (45-65 days and 65-85 days after sowing) as

affected by tow irrigation treatments (irrigated and stressed) and their

interactions are presented in Table (7).

Table 7. Means of crop growth rate (CGR) as affected by irrigation



Characteristic

Crop growth rate (CGR)

CGR 1 (45-65 days) CGR 2 (65-85 days) 2009/10 2010/11 2009/10 2010/11


Irrigated 217 235 464 478

Stressed 198 205 374 405

LSD 0.05 1.39 80.2 3.65 8027

Reduction% 9 13 19 15

Main effect of barley genotypes Giza 126 211 225 401 452

Giza 132 219 233 437 443

Beacher 196 213 409 443

Giza 121 209 220 432 454

L 1 202 212 383 407

L 2 200 202 416 449

L 3 212 222 415 425

L 4 223 242 455 476

L 5 209 228 432 456

L 6 207 217 433 455

L 7 205 214 416 433

L 8 221 237 445 469

L 9 212 224 427 459

L 10 205 217 409 428

L 11 211 224 416 448

L 12 208 220 400 409

L 13 210 218 402 417

L 14 198 210 414 426

L 15 206 217 422 446

L 16 191 204 415 433

LSD 0.05 4.38 6.58 11.53 6.86


- 37 -

Cont. Table 7.

Characteristic Crop growth rate (CGR) Interaction

Genotype CGR 1 (45-65 days) CGR 2 (65-85 days)

2009/10 2010/11 2009/10 2010/11 Irrigated Stressed Reduction% Irrigated Stressed Reduction% Irrigated Stressed Reduction% Irrigated Stressed Reduction%

Giza 126 217 206 5 234 216 8 425 378 11 491 413 16

Giza 132 231 206 11 259 208 20 479 394 18 476 410 14

Beacher 209 183 12 217 209 4 469 348 26 492 394 20

Giza 121 215 202 6 227 213 6 489 375 23 505 403 20

L 1 211 193 9 234 189 19 410 356 13 443 371 16

L 2 213 187 12 230 173 25 450 382 15 454 444 2

L 3 229 194 15 250 194 22 460 369 20 475 375 21

L 4 225 220 2 270 214 21 503 407 19 477 475 1

L 5 217 201 7 243 213 12 481 383 20 494 418 15

L 6 215 199 7 222 211 5 479 387 19 493 416 15

L 7 210 199 5 231 196 15 461 371 20 481 384 20

L 8 226 215 5 238 235 2 489 401 18 504 433 14

L 9 217 206 5 224 224 0 483 370 23 498 420 16

L 10 219 192 12 228 205 10 450 368 18 465 391 16

L 11 220 202 8 236 212 10 467 366 22 480 415 13

L 12 226 189 16 242 197 19 435 366 16 442 376 15

L 13 219 200 9 233 204 13 441 363 18 441 393 11

L 14 208 189 9 226 193 14 463 364 21 472 380 20

L 15 214 198 7 226 207 8 472 373 21 487 404 17

L 16 198 184 7 222 185 17 470 361 23 493 373 24

LSD0.05 6.19 9.31 16.31 9.70


- 38 -

Results showed highly significant differences of CGR values due to

irrigation treatments at both growth intervals. In general, the CGR means

in the stressed treatment had been significantly lower than the irrigated

treatment, where the CGR reduction as the result of water stress. CGR

changes turned resembled in both treatments, but the irrigated treatment

had superiority over that of the stressed treatment during all studied stages.

Reduction of the CGR under water stress condition was due to reduction

of the LAI and the NAR. These results are in agreement with those

obtained by Alam et al. (2003), Shahen (2005), Jazy et al. (2007) and

Mollah and Paul (2008).

Genotypes had highly significant different in CGR means. Where,

Giza 132, L4 and L8 had the highest values in the first growth intervals in

both seasons. Most genotypes exceeded Giza 126 in the second growth

intervals, especially Giza132, L4 and L8 in first season, while L8 only had

the highest value in the second one.

Highly significant interaction between barley genotypes and

irrigation treatments was found in the two growth intervals. In the first

season under irrigated treatment, Giza 132, L3, L4, L8 and L12 had the

highest values, while Giza 121 and L8 in the second season. In the first

season, all genotypes except L1, L12 and L13 exceeded Giza 126 in the

second growth intervals under irrigation condition. However, L4 and L8

had the highest values under the stressed treatment compared to Giza

126.in the second season Giza 121 and L8 had the highest values in the

second growth intervals under irrigation condition, while L2, L4 and L8

were the highest under stress condition. The CGR reduction ratio between

irrigated and stressed treatments in the second growth intervals continued

more violently compared with the first growth intervals.


- 39 -

4.1.4- Net assimilation rate (NAR):

Net assimilation rate as affected by irrigation treatments and barley

genotypes as well as their interactions in tow growth intervals are

presented in Table (8).

Table 8. Means of net assimilation rate (NAR) as affected by irrigation



Characteristic

Net assimilation rate (NAR)

NAR 1 (45-65 days) NAR 2 (65-85 days)

2009/10 2010/11 2009/10 2010/11


Irrigated 6.56 7.08 11.88 11.90

Stressed 6.34 6.47 11.15 10.66

LSD 0.05 0.05 .0.0 0.10 .0.7

Reduction% 3 9 6 10

Main effect of barley genotypes

Giza 126 6.59 7.02 11.00 11.57

Giza 132 6.72 7.20 11.75 11.17

Beacher 6.19 6.77 11.66 11.82

Giza 121 6.46 6.79 11.93 11.74

L 1 6.29 6.50 10.93 10.78

L 2 6.32 6.33 11.52 11.50

Documents

رسالة السيد السيد الشاوى