بسم الله الرحمن الرحيم

بسم الله الرحمن الرحيم

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89األعراف:

الله العظيم صدق

RESEARCHER

MOHAMED TAHA ABD AL-RAHMAN ZALAMA

B.Sc. Agric. Sci. (Agronomy), Faculty of Agric., Mansoura University (1999)

M. Sc. Agric. Sci. (Agronomy), Faculty of Agric., Mansoura University (2007)

Research assistant in Seed Tech. Res. DepartmentField Crops Institute

Agricultural Research Center, Egypt

للحصول علي درجة دكتوراه الفلسفة في العلوم الزراعية ( نبات زراعي)*** تحت إشراف: *أ.د/ محب طه صقر / محمد طه زلمه من الباحثة المقدمالرسالةمناقشة ** أ.د/ زين العابدين عبد الحميد محمد *** رئيس بحوث/ مروءة إسماعيل عطا

TITLE OF THESISEFFECT OF SOME ANTIOXIDANTS ON SEED QUALITY AND YIELD OF

FABA BEAN PLANTS UNDER SALINITY STRESS

تأثير بعض مضادات األكسدة على جودة

التقاوي والمحصول في الفول البلدي تحت ظروف

اإلجهاد الملحي.للحصول علي درجة دكتوراه الفلسفة في العلوم الزراعية ( نبات زراعي)*** تحت إشراف: *أ.د/ محب طه صقر / محمد طه زلمه من الباحثة المقدمالرسالةمناقشة

** أ.د/ زين العابدين عبد الحميد محمد *** رئيس بحوث/ مروءة إسماعيل عطا

Supervision committee

Zein EL-ABEDIN ABD EL- HAMID

MOHAMEDProf. Dr. of Agric.

Head of Botany Dept. Faculty of Agric.

Mansoura University

MAROUAH ISMAEL ATTAChief Researcher

Seed Tech. Res. Dept. Field Crops Institute

Agric. Res. center

MOHEB TAHA SAKRProf. Dr. of Plant Physiology,

Faculty of Agric., Mansoura University


Award and Discussion Committee

Prof. Dr./ Moheb Taha SakrProf. Dr. of Plant Physiology, Faculty of Agric., Mansoura University

Prof. Dr./ Hosny Mohamed Abd El-DayemProf. of Agric. Botany, Faculty of Agric., Moshtohor University

Prof. Dr./ Mahmoud Mohamed DarwishProf. Dr. of Plant Physiology, Faculty of Agric., Mansoura University

Prof. Dr./ Zein El-Abedin A.H. MohamedProf. Dr. of Agric. Head of Botany Dept. Faculty of Agric. Mansoura University


Faba bean; is a member of family Fabaceae (Leguminosae) which is the third largest family of flowering plants with 650 genera and over 18,000 species.

In Egypt, area harvested of faba bean plants in 2005 was 205.661 fad. and decreased in 2011 to 136.401 fad., (FAO. 2013) Egyptian faba bean is facing several problems at the present time. Its effective on both of faba bean productivity, yield and it`s components and seed quality.

one of the most important factors which causes reduction of area harvested of faba bean plants is exposure of large areas of lands for salinity as well as sensitivity of faba bean to medium levels of salinity stress.

Application of antioxidants is one of the most important ways to increasing salt tolerance of plants. Treatments of [Salicylic acid (SA), Ascorbic acid (ASA), Tochopherol (TOCO), Humic acid (HA) and Yeast extract] proved effective in reducing the adverse effect of salinity on growth, yield and chemical composition of faba bean plants.

INTRODUCTION

The experiment was designed to;

Investigated the influence of some antioxidant materials on the harmful effects of different salinity stress levels on vegetative growth, yield and its components, biochemical constituents, nutrient element contents and protein percentage of faba bean plant (Vicia faba, L.) cv. Sakha 1 obtained from Agric. Res. Center, Ministry of Agric., Egypt.

OBJECTIVES OF THE STUDY

This work includes 3 parts;

1- Pot experiment.

2- Field experiment.

3- Seed quality tests.

EXPERIMENTS UNDER THIS STUDY

Pot experiments includes 3 parts:-

1- Seed presoaking.

2- Plant foliar spraying.

3- Presoaking and foliar spraying together.

Pot experiments were performed twice during

the growing seasons of (2010/2011 and

2011/2012)

Pot Experiment

FIRST FACTOR:-

Salinity stress levels:

1- 320 (mg/l) as (Control).

2- 2000 (mg/l).

3- 4000 (mg/l).

4- 6000 (mg/l).

5- 8000 (mg/l).

FACTORS UNDER STUDY

FACTORS UNDER STUDY

SECOND FACTOR

Antioxidant

materials:- 1- Tap water (control).

2- Salicylic acid (SA) at (250

mg/l).

3- Ascorbic acid (ASA) at

(250 mg/l).

4- α –Tocopherol (TOCO) at

(100 mg/l).

5- Hamic acid (HA) at (1000

mg/l).

6- Yeast extracts (2000

mg/l).

A- Vegetative growth

observations:

1- Shoot length (cm).

2- Root length (cm).

3- Shoot fresh weight (g).

4- Shoot dry weight (g).

5- Root fresh weight (g).

6- Root dry weight (g).

7 -Leaf area (cm2/plant).

B- Yield and its

components:

1- Number of pods / plant.

2- Pods weight / plant (g).

3- Number of seeds / plant.

4- Seeds weight / plant (g).

5- 100- Seed weight (g).

STUDIED CHARACTERISTICS

C- Biochemical constituents :

1- Photosynthetic Pigments. 2- Proline concentration.

3- Total ascorbic acid. 4- Total phenols.

5- Potasium and sodium. 6- Seeds protein %.

STATISTICAL ANALYSIS

All data of the experiment statistically

analyzed according to the technique of

analysis of variance “ANOVA” for the

“Randomized Complete Block Design”

by means of “MSTAT-C” Computer

software package.

The treatment means were compared

using the Least Significant Differences

“N- LSD 5%”.

320mg/l 2000mg/l 4000mg/l 6000mg/l 8000mg/l0

0.2

0.4

0.6

0.8

10.822

0.354

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

A (

mg

/g f

. wt)


0.2

0.4

0.6

0.8

10.822

0.354

Foliar SprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

A

(mg

/g f

. wt)


0.2

0.4

0.6

0.8

1 0.932

0.362

Presoaking and Foliar sprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

A (

mg

/g f

. wt)

Fig (1): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying together) as well as their interactions on chlorophyll (A) content in shoots of faba bean plant.


0.1

0.2

0.3

0.4

0.5 0.387000000000003

0.184

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

B

(mg

/g f

. wt)


0.1

0.2

0.3

0.4 0.378000000000003

0.177

Foliar SprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

B

(mg

/g f

. wt)


0.1

0.2

0.3

0.4

0.50.388000000000003

0.186


SA

ASA

TOCO

HA

YEAST

Salinity Levels

ch

loro

ph

yll

B

(mg

/g f

. wt)

Fig (2): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on chlorophyll (B) content (mg/g f.wt) in shoots of faba bean plant.


0.050.1

0.150.2

0.250.3

0.35 0.324000000000003

0.164

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Ca

rote

no

ids

c

on

ten

t (m

g/g

. f. w

t)


0.050.1

0.150.2

0.250.3

0.350.312000000

000003

0.161

Foliar SprayingTAP SAASATOCOHAYEAST

Salinity LevelsCa

rote

no

ids

co

n-

ten

t (

mg

/g. f

. wt)


0.1

0.2

0.3

0.4 0.335000000000003

0.158000000000001


SA

ASA

TOCO

HA

YEAST

Salinity LevelsCa

rote

no

ids

co

n-

ten

t (

mg

/g. f

. wt)

Fig (3): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying together) as well as their interactions on carotenoids content (mg/g. f. wt) in the shoots of faba bean plant.


2

4

6

8

2.14

6.52

Pre-SoakingTAP SAASATOCOHAYEAST

Salinity Levels

Pro

line

co

nte

nt

(mg

/g. f

. wt)


2

4

6

8

2.24

6.46

Foliar SprayingTAP SAASATOCOHAYEAST

Salinity Levels

Pro

line

co

nte

nt

(mg

/g. f

. wt)

Fig (4): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying together) as well as their interactions on proline content (mg/g. f. wt) of faba bean plant.


2

4

6

8

2.22

6.72Presoaking and Foliar spraying

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Pro

line

co

nte

nt

(m

g/g

. f. w

t)


50

100

150

200

79.52

177.36Pre-Soaking

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

As

co

rbic

co

nte

nt

(m

g/ 1

00

g f

. wt)


50

100

150

200

77.36

171.28Foliar Spraying

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

As

co

rbic

co

nte

nt

(m

g/ 1

00

g f

. wt)


50

100

150

200

80.43


TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

As

co

rbic

co

nte

nt

(m

g/ 1

00

g f

. wt)

Fig (5): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on ascorbic acid content (mg/ 100g f. wt) of faba bean plant.


20

40

60

80

100

27.45

78.43

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Ph

en

ol c

on

ten

t (

mg

/ 10

0g

f. w

t)


20

40

60

80

100

26.54

78.54

Foliar SprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Ph

en

ol c

on

ten

t (m

g/ 1

00

g f

. wt)


20

40

60

80

100

28.43


TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Ph

en

ol c

on

ten

t (

mg

/ 10

0g

f. w

t)

Fig (6): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying

or Presoaking and Foliar spraying) as well as their interactions on total phenol

content (mg/ 100g f. wt) of faba bean plant.


0.5

1

1.5

2

2.5

1.09

2.12Pre-Soaking

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na

+ c

on

ten

t (

mg

/g. D

W)


0.5

1

1.5

2

2.5

1.12

2.23Foliar Spraying

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na

+ c

on

ten

t (m

g/g

. DW

)


0.5

1

1.5

2

2.5

0.93


TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na

+ c

on

ten

t (m

g/g

. DW

)

Fig (7): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying

or Presoaking and Foliar spraying together) as well as their interactions on Na+

content (mg/g. DW) in shoots of faba bean plant.


0.51

1.52

2.53 2.78

1.32

Foliar SprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(mg

/g. D

W)


0.51

1.52

2.53

3.52.92

1.3


SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(mg

/g. D

W)


0.51

1.52

2.53

3.52.86

1.29

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(m

g/g

. DW

)

Fig (8): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying together) as well as their interactions on K+ content (mg/g. DW) in shoots of faba bean plant.


1

2

3

4

1.81

4.03Pre-Soaking

Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

co

nte

nt

(mg

/g. D

W)


1

2

3

4

1.84

3.93Foliar spraying

Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

co

nte

nt

(m

g/g

. DW

)


1

2

3

4

1.72


Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

co

nte

nt

(m

g/g

. DW

)

Fig (9): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on Na+ content (mg/g. DW) in roots of faba bean plant.


0.5

1

1.5

2

2.5 2.25 2.24

0.55

Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(m

g/g

. DW

)


0.5

1

1.5

2

2.5 2.23

0.58

Foliar SprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(m

g/g

. DW

)


0.5

1

1.5

2

2.5 2.34 2.33

0.57


SA

ASA

TOCO

HA

YEAST

Salinity Levels

K+

co

nte

nt

(m

g/g

. DW

)

Fig(10): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on K+ content (mg/g. DW) in roots of faba bean plant.

Fig(12): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on Na+/K+ ratio in shoots of faba bean plant.


0.250.5

0.751

1.251.5

1.75

0.380000000000004

1.64Pre-SoakingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na+

/K+

rat

io i

n s

ho

ots


0.5

1

1.5

2

0.4

1.69000000000001Foliar Spraying

TAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na+

/K+

rat

io i

n s

ho

ots


0.250.5

0.751

1.251.5

1.75

0.320000000000004

1.65Presoaking and Foliar sprayingTAP

SA

ASA

TOCO

HA

YEAST

Salinity Levels

Na+

/K+

rat

io i

n s

ho

ots

Fig(11): Effect of salinity stress levels and applied antioxidants as (Presoaking, Foliar spraying or Presoaking and Foliar spraying) as well as their interactions on Na+/K+ ratio in roots of faba bean plant.


0.8

7.33Pre-Soaking

Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

/K+

rat

io i

n r

oo

ts


2

4

6

8

0.830000000000001

6.78Foliar spraying

Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

/K+

rat

io i

n r

oo

ts


2

4

6

8

0.740000000000002


Tap

SA

ASA

TOCO

HA

Yeast

Salinity levels

Na+

/K+

rat

io i

n r

oo

ts

The experiment under study was carried out within

the period of November-Marsh 2010/2011 in Tag El-Ezz

Research Station, Dakahlia Governorate, Agric. Res.

Center., Ministry of Agric. Egypt to investigate the role

of action of some selected antioxidants on the harmful

effect of soil salt stress on faba bean plant.

FIELD Experiment


FACTORS UNDER STUDYFIRST FACTOR:-

Salinity stress levels:

1- 1900 (mg/l).

2- 3200 (mg/l).

SECOND FACTOR:-

Antioxidant materials:

1- Tap water. 2- Salicylic acid (SA) at

(250 mg/l).

3- Ascorbic acid (ASA) at (250 mg/l). 4- α –

Tocopherol (TOCO) at (100 mg/l).

5- Hamic acid (HA) at (1000 mg/l). 6- Yeast extracts

(500 mg/l).

STUDIED CHARACTERISTICS A- Vegetative growth observations:

1- Plant height (cm).

2- Plant fresh weight (g).

3- Plant dry weight (g).

4- Leaf area (cm2/plant).

B- Yield and its components: 1- No. of pods/plant.

2- Weight of pods/plant (g).

3- Weight of seeds/plant (g).

4 -Seed yield (Ardab/fad).

Fig (1): Plant height/cm of faba bean plants as influenced by salinity stress levels, applied antioxidants and their interactions during the growing seasons 2010/2011.

1900 mg/l 3200 mg/l 1900 mg/l 3200 mg/l 1900 mg/l 3200 mg/l0

10

20

30

40

50

60

70

80

90

56.93

48.41

55.03

46.12

55.93

47.19

75.81

63.74

74.68

62.8

78.38

67.4

Presoaking Foliar spraying Presoaking & Foliar

TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

Pla

nt

hei

gh

t/cm

Fig (2): Plant fresh weight (cm) of faba bean plants as influenced by salinity stress levels, applied antioxidants and their interactions during the growing seasons 2010/2011.


10

20

30

40

50

60

70

80

90

48.84

40.13

46.33

40.05

50.79

41.47

78.38

61.41

74.06

60.16

79.73

64.29

Presoaking Foliar spraying Presoaking & Fo-liar

TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

Pla

nt

fres

h w

eig

ht

(g)

Fig (3): Plant dry weight (g) of faba bean plants as influenced by salinity stress levels, applied antioxidants and their interactions during the growing seasons 2010/2011.


1

2

3

4

5

6

7

8

9

5.58

4.29

5.44

4.19

5.72

4.24

8.13

6

7.91

5.77

8.33

6.23


TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

Pla

nt

dry

we

igh

t (g

)


100

200

300

400

500

600

700

800

590.37

486

578.53

478.03

582.73

484.229999999999

696.8

608.03

690.1

599.9

709.93

621.47


TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

Le

af

Are

a (

cm

2/p

lan

t)

Fig (4): Leaf Area (cm2/plant) of faba bean plants as influenced by salinity stress levels, applied antioxidants and their interactions during the growing seasons 2010/2011.

Fig (5): No. of pods/plant as influenced by salinity stress levels, applied antioxidants and their interactions during the growing seasons 2010/2011.


3

6

9

12

15

18

21

9.46

6.54

10.01

6.65

10.25

7.18

17.84

13.59

17.07

13.71

19.35

15.15

Presoaking Foliar spraying Presoaking & Fo-liar

TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

No

. o

f p

od

s/p

lan

t


5

10

15

20

25

30

35

40

45

22.22

16.38

22.25

16.21

23.36

16.67

34.8

28.18

33.16

25.63

39.18

31.76


TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

We

igh

t o

f p

od

s/p

lan

t

Fig (6): Weight of pods/plant as influenced by salinity stress levels, applied antioxidants and their interactions during the growing season 2010/2011.


5

10

15

20

25

30

35

40

45

25.19

20.6

25.58

19.9899999999999

25.9

20.77

38.37

33.31

36.74

31.05

41.83

36.48


TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

No

. o

f s

ee

ds

/pla

nt

Fig (7): No. of seeds/plant as influenced by salinity stress levels, applied antioxidants and their interactions during the growing season 2010/2011.


5

10

15

20

25

30

35

16.91

11.1

16.45

10.48

18.28

11.67

26.83

21.65

25.31

18.74

31.08

24.34


TAP

SA

ASA

TOCO

HA

YEAST

Salinity stress

We

igh

t o

f s

ee

ds

/pla

nt

Fig (8): Weight of seeds/plant as influenced by salinity stress levels, applied antioxidants and their interactions during the growing season 2010/2011.

CONCLUSIONS

CONCLUSIONS


A: Effect of salinity stress on:-

1- Growth attributes: All pot experiments under this study recorded that, all salinity stress levels hardly decrease all growth parameters of faba bean plants when compared with unstressed treatment (control at 320 mg/l) through the two physiological development stages (45 and 90 days) during the two experimental seasons (2010/2011 and 2011/2012).

In this regard, the most effective salinity stress level was (8000 mg/l) followed by (6000 mg/l,4000 mg/l and 2000 mg/l), respectively.

2-Yield and it`s components attributes:

The results which were obtained showed that, there is a negative correlation between high salinity stress levels and yield of faba bean plants in all pot experiments (presoaking, foliar spraying or presoaking and foliar spraying together) during the two growing seasons.

All Salinity levels recorded significant reduction in the yield and it`s components, when compared with unstressed treatment (320 mg/l). The great reduction regarding to (8000 mg/l) followed by (6000 mg/l).

3- Biochemical constituents:I. Photosynthetic pigments: All salinity stress levels

decreased photosynthetic pigments in the shoots of faba bean plant during the two growing seasons in all pot experiments.

Regarding, the great reduction was observed by salinity level (8000 mg/l).

II. Proline, ascorbic acid and phenols: Salinity stress levels caused a

slightly increase in the contents of each proline, ascorbic and phenols in the shoot of faba bean plant, while compared with unstressed treatment (control at 320 mg/l) at all pot experiments under study.

The most effective salinity stress level was (8000 mg/l) followed by (6000 mg/l).

III. Na+, K+ content and Na+/K+ ratio:-

Na+ content was increased by salinity stress levels while K+ content was decreased in the shoot and roots of faba bean plant. High salinity level (8000 mg/l) was most effective in this respect.

All salinity stress levels increased Na+/K+ ratio, when compared with unstressed treatment control (320 mg/l) in all pot experiments. Regarding, the higher degree of Na+/K+ ratio caused by salinity stress level (8000 mg/l).

B- Effect of applying antioxidants on:-

1- Growth attributes: All selected antioxidants (SA, ASA, TOCO, HA and Yeast) which

applied in all pot experiments (presoaking, foliar spraying or presoaking and foliar spraying together) significantly increase growth parameters of faba bean plants when compared with plants treated with control (Tap water) through the two physiological development stages (45 and 90 days) during the two growing seasons.

In this respect, ASA (250 mg/l) recorded the most significant increase in growth attributes of faba bean plants at all experiments during the two growing seasons.

2- Yield and it`s components: All antioxidants which were applied in all pot experiments during

the two growing seasons recorded the higher degree of yield and it`s components when compared with untreated plants (control).

The most effective antioxidants in this respect were ASA (250 mg/l).

3- Biochemical constituents:-3.1- Photosynthetic pigments: Applied antioxidants on faba bean plants as presoaking, foliar

spraying or presoaking and foliar spraying together let to enhancing the content of chlorophyll A, B and carotenoids against planted treated with control (Tap water). Concerning, ASA (250 mg/l) recorded the great values.

3.2- Proline, ascorbic acid and phenols: Selected antioxidants caused synergistic effect when applied on faba

bean plants when compared with control treatment (Tap water) in all pot experiments. ASA and SA was the most effective in this respect.

3.3- Na+, K+ content and Na+/K+ ratio: Applied antioxidants slightly decreased Na+ contents and increased

K+ when compared with untreated plants (control treatment) in all pot experiments under study.

Applied selected antioxidants clearly decreased Na+/K+ ratio when compared with untreated plants.

C: Effect of interaction between salinity stress and applying antioxidants on:-

1- Growth attributes:

With regard to the interaction treatments, the data indicated that applied selected antioxidants (SA, ASA, TOCO, HA and YEAST) in all pot experiments at the two physiological stages (45 and 90 days) significantly enhanced growth attributes of faba bean plants under salinity stress levels when compared with plants treated with control (Tap water) grown under the same salinity stress levels during the two growing seasons.

Concerning, treatment ASA (250 mg/l) at salinity level (320 mg/l) recorded the highest values of faba bean growth attributes. Applied antioxidants could basically mitigate the harmful effect of salinity stress on growth of faba bean plants grown under saline soil.

2- Yield and it`s attributes: With respect to the interaction treatments, the

data showed that applied antioxidants increased yield and it`s attributes of faba bean plants under salinity stress levels when compared with control plants treated with tap water grown under salinity stress levels.

Accordingly, applied antioxidants could be hardly alleviating the reduction caused by salinity stress on yield of faba bean plant. ASA was the most effective in this respect, then SA, Yeast, HA and TOCO, respectively.

3- Biochemical constituents:3.1- Photosynthetic pigments: Interaction treatments of applied antioxidants

with salinity stress levels hardly increased photosynthetic pigments compared with plants treated with control (Tap water) grown under the same salinity stress levels at all pot experiments, but these increases still less than control plants.

In this regard applied antioxidants basically mitigate the harmful effect of salinity stress on photosynthetic pigments. ASA (250 mg/l), SA (250 mg/l) and Yeast extract (2000 mg/l) respectively, were more effective in this respect.

3.2- Proline, ascorbic acid and phenols: Regarding the interaction treatments, data cleared that

applied selected antioxidants materials with the selected salinity stress levels under this study, hardly increased Proline, ascorbic acid and phenols content in faba bean shoots when compared with untreated plants (control).

3.3- Na+, K+ content and Na+/K+ ratio: Salinity stress treatment combined with applied

antioxidants slightly decreased Na+ content and Na+/K+ ratio, while increased K+ content in both shoot and root of faba bean plant, when compared with applied control (Tap water) with the same salinity levels treatments.

Applied antioxidants alleviate the harmful effects of salinity stress and decreased the Na+ and Na+/K+ ratio in shoots and roots of faba bean plants against control treatment.

FIELD EXPERIMENTThe main obtained results of

these studyA: Growth characters: All growth characters of faba bean plants significantly

enhanced by applied antioxidants (Ascorbic, Salicylic, α- Tocopherol, Humic and Yeast extract) compared with treated plants with control (Tap water) in the two soils salt area (A1 and A2).

The data also indicated that applied antioxidant materials were more effective in salt soil area (A1).

ASA (250 mg/l) was the most effective in this respect followed by SA (250 mg/l), Yeast (2000 mg/l), HA (1000 mg/l) and TOCO (100 mg/l) respectively.


B: Yield and it`s components: Applied antioxidants materials significantly

increased yield and it`s components (No. of pods/plant, weight of pods/plant, weight of seeds/plant and seed yield (Ardab/fad) in the two salt soil areas especially (A1) compared with the control treatment (Tap water).

The obtained data recorded that applied antioxidant materials could mitigate the harmful effect of high soil salt stress levels on yield and its components of faba bean plants.

ASA (250 mg/l) followed by SA (250 mg/l) were more effective in this regard.

RECOMMENDATION This investigation indicated that, it can alleviate and mitigate the harmful effect of different salinity stress levels on faba bean plants by applied non-enzymatic antioxidants (Ascorbic acid, Salicylic acid, α- Tocopherol, Humic acid and Yeast extract) in experiments (presoaking, Foliar spraying or presoaking and foliar spraying together). These antioxidant materials caused an increments effect on growth and it`s attributes, yield and it`s components also chemical constituents. The Results mention previously show that the best antioxidant material is Ascorbic acid (ASA) followed by Salicylic acid (SA), Yeast extract, Humic acid and α- Tocopherol respectively. In addition, with these regard faba bean plants can be planted in wide range of saline soil in Egypt with applying natural safety antioxidants.

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