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Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
DOI: https://doi.org/10.24925/turjaf.v7i4.598-605.2281
Turkish Journal of Agriculture - Food Science and Technology
Available online, ISSN: 2148-127X | www.agrifoodscience.com | Turkish Science and Technology
Variation in Chemical Constituents of Siyez Wheat (Triticum monococcum L.)
in Response to Some Abiotic Stress Factors
Nezahat Turfan1,a,*, Temel Sarıyıldız2,b, Ekrem Mutlu3,c
1Department of Biology, Faculty of Arts and Sciences, Kastamonu University, 37200 Kastamonu, Turkey
2Department of Forest Engineering, Faculty of Forestry, Bursa Technical University, 16310 Bursa, Turkey
3Aquaculture Department, Faculty of Fisheries, Kastamonu University, 37200 Kastamonu, Turkey
*Corresponding author
A R T I C L E I N F O
A B S T R A C T
Research Article
Received : 15/10/2018
Accepted : 21/12/2018
Main aim of this study was to determine the effects of different salt contents (75 mM, 150 mM
and 225 mM NaCl), heavy metal (0.2 mg/L FeCl3, NiCl2, ZnCl2), lime (2 mg/L CaCO3), drought
(50%) and pollution (0.2 mg/L dust of factories) on photosynthetic pigments, malondialdehyde
(MDA), hydrogen peroxide (H2O2) levels, the ascorbate peroxidase (APX), catalase (CAT),
guaiacol peroxidase (GPOX) and superoxide dismutase (SOD) in Siyez wheat (Triticum
monococcum L.). All experiments were carried out under laboratory conditions with 16 hour-day
and 8 hour-night photoperiod in an incubator at 23 ± 1°C. Results showed that mean chlorophyll-
a concentration was highest in the siyez seedlings treated with the pollution, while both mean
chlorophyll-b and total chlorophyll concentrations were highest with 75 mM salt application.
Mean total carotenoid was, however, highest with the drought treatment and mean relative water
content was highest with NiCl2 application. Mean MDA and H2O2 contents were found to be
highest in the siyez seedlings treated with 225 mM salt, whereas they were lowest with NiCl2
treatment. Mean proline content was highest with the NiCl2 treatment compared to the lowest
concentration in the control siyez seedlings (82 µmol/g). Mean APX, CAT and GPOX activities
were noted to be highest in the siyez seedlings treated with NiCl2. In general, the siyez seedlings
showed high tolerance to the pollution, NiCl2 and drought with having highest photosynthetic
pigments, proline, protein content and enzymes activities. Among all treatments, 225 mM NaCl
and CaCO3 negatively influenced chemical compounds of the siyez seedling. When all data are
taken into consideration, it can be said that higher photosynthetic pigments, proline contents,
antioxidant enzymes activities and lower MDA and H2O2 levels play an important role in the
resistance of siyez seedlings against abiotic stress conditions.
Keywords:
Abiotic stresses
Siyez
Tolerance
Wheat
Antioxidant
Türk Tarım – Gıda Bilim ve Teknoloji Dergisi 7(4): 598-605, 2019
Siyez Buğday Çeşidinin Kimyasal Bileşenlerinin Bazı Abiyotik Stres
Koşullarına Karşı Değişimi
M A K A L E B İ L G İ S İ
Ö Z
Araştırma Makalesi
Geliş : 15/10/2018
Kabul : 21/12/2018
Bu çalışmanın esas amacı farklı konsantrasyonlarda tuz (75 mM, 150 mM ved 225 mM NaCl, ağır
metal (0.2 mg/L FeCl3, NiCl2, ZnCl2), kireç (2 mg/L CaCO3), kurak (%50) ve kirlilik (0.2 mg/L
fabrika baca tozu) uygulamalarının Siyez buğdayının (Triticum monococcum L.) fotosentetik
pigment, malondialdehit (MDA), hidrojen peroksit (H2O2), prolin, toplam çözünür protein,
askorbat peroksidaz (APX), katalaz (CAT), guaiakol peroksidaz (GPOX) ve süperoksit dismutaz
(SOD) aktiviteleri üzerine etkilerini araştırmaktadır. Bulgulara göre klorofil a miktarı kirlilik
uygulamasında, klorofil b ve toplam klorofil miktarı ise 75 mM tuz uygulamasında en yüksektir.
Bununla birlikte toplam karotenoit kuraklık uygulamasında ve bağıl su içeriği de NiCl2
uygulamasında en yüksek değere ulaşmıştır. MDA ve H2O2 içeriği 225 mM tuz uygulamasında en
yüksek, NiCl2 uygulamasında en düşüktür. Prolin içeriği kontrole göre (82 µmol/g) NiCl2
uygulamasında en yüksektir. APX, CAT ve SOD aktiviteleri NiCl2 uygulamasında yüksek olarak
bulunmuştur. Sonuç olarak siyez fideleri yüksek pigment, prolin, protein ve enzim aktiviteleri ile
kirlilik, NiCl2 ve kurak uygulamalarına yüksek tolerans göstermiştir. Uygulamalardan 225 mM
tuz ve CaCO3 siyez fidelerindeki kimyasal bileşenleri negative olarak etkilemiştir. Tüm veriler
göz önünde bulundurulduğunda yüksek fotosentetik pigment, prolin ve antioksiadant enzim
aktiviteleri ve düşük MDA ve H2O2 miktarlarının siyezin abiyotik stres koşullarına toleransında
önemli rol oynadığı söylenebilir.
Anahtar Kelimeler:
Abiyotik stres
Siyez
Tolerans
Buğday
Antioksidan
a
nturfan@kastamonu.edu.tr
https://orcid.org/0000-0002-5753-0390
b
temel.sariyildiz@btu.edu.tr
https://orcid.org/0000-0003-3451-3229
c
ekrem-mutlu@hotmail.com
https://orcid.org/0000-0002-6000-245X
This work is licensed under Creative Commons Attribution 4.0 International License
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
599
Introduction
Wheat (Triticum L. spp.) is one of the most important
cereal crops around the world, which can be cultivated in a
wide variety such as temperate, high-rainy areas and warm,
dry and cold environment. It has over 713 million tons in
2013 as annual production (Faostat, 2014). However,
generally warm and drought climatic conditions create the
ideal environment for salinity and barrenness formation in
any region where the wheat grows (Başer et al., 2005). On
the other hand, the accumulation of zinc, iron, lead,
cadmium, nickel and other heavy metals in dense industrial
zones which are close to cultivation lands affect wheat crop
production by leading to heavy metal toxicity ( Mutlu et.al.,
2013; Mutlu et.al., 2014; Mutlu et.al., 2016; Mutlu and
Kurnaz, 2017; Barut et al., 2017; Kurnaz and Turfan, 2017;
Sarıyıldız et al., 2017; Mutlu and Kurnaz, 2018). Many
authors stated that salinity, heavy metals and element
toxicity, excessive calcerous soil and also drought
especially before grain filling may reduce leaf and stem
properties such as leaf area, length of leaf, length and
strength of internode (Ostrowska et al., 2014; Turkyılmaz
et al., 2018). It has been reported that deviations from
optimal growth and development of crops repress
photosynthetic activity which is main factor on grain
quality and yield (Saeidi and Abdoli, 2016; Konuşkan et
al., 2017). On the other side, those conditions can stimulate
oxidative stress that leads to disruption of chloroplast
structure, destruction of photosynthetic pigments,
degradation protein and amino acid, inhibition of enzymes,
increasing free radicals and malondildeyde (Neto et all.,
2006; Turkyilmaz et., 2014). Due to the increased nutrient
requirements and the limited availability of agricultural
lands, in parallel with population increase, selecting wild
and improved genotypes with high tolerance to stress
factors in regions where salinity, lime/drought and heavy
metal toxicity are dominant will contribute to more
efficient utilization of existent land resources. In this
context, Siyez (einkorn) grown well around Kastamonu
region is an important ancestral gene source. It has been
reported that einkorn is an ancient wheat which originates
in the mountainous areas of Turkey and its wild progenitor
(T. baeoticum Boiss.) (Lùje et al., 2003). In addition,
compared to common wheat, einkorn is generally more
resistant to diseases and has the ability to withstand
drought, but the yields of einkorn are less compared to the
common wheat variety (Shewry and Hey, 2015; Nakov et
al., 2016). San et al., (2015) analysed the polymorphism in
seed endosperm proteins for Turkish cultivated einkorn
wheat (Triticum monococcum ssp. monococcum). They
showed that it had the the high number of proteins and
genetic variation, and increased interest in organic
products. In order to better understand the mechanism of
resistance to stress factors, the determination of
morphological parameters as well as physiological
measurements in different wheat varieties can provide us
more accurate steps to select the appropriate species and
varieties. We, therefore set up a study to investigate the
effects of salt, heavy metals, drought and lime treatments
on the green parts photosynthetic pigments, proline, total
soluble protein, MDA, H2O2 amount and APX, CAT,
GPOX and SOD activities were siyez wheat (Triticum
monococcum L.). We used FeCl3, NiCl2 and ZnCl2 in this
present study in order to understand the effects of the heavy
metal on siyez wheat since those three heavy metals are
known to reduce plant growth and also they are the
elements in the components of photosynthesis,
carbohydrate and respiratory reactions.
Materials and Methods
Laboratory Incubations
All experiments were carried out under laboratory
conditions with 16 hour-day and 8 hour-night photoperiod
in an incubator at 23 ± 1°C. The seeds were planted in the
plastic seeding pots (Figure 1) containing 1:1:1 garden soil,
peat and sand (tree replicate each) and placed in the
incubators until analyses (Figure 2). In order to apply salt,
heavy metal, CaCO3 and pollution to the seedlings, each
treatment group was dissolved in ArnonHoagland
(Hoagland and Arnon, 1950) nutrient solution. The nutrient
solution consisted of 2.5 mM NO3-, 0.5 mM NH4+, 2 mM
K+, 1 mM Ca2+, 0.5 mM Mg2+, 0.05 mM Fe-EDTA, 5 &
mu; M Mn2+, 0.5 & mu; M Zn2+, 0.5 & mu; M Cu 2+, 1 mM
Cl, 0.55 mM SO4-2, 0.5 mM PO4-3, 1.5 & mu; M BO3, 0.1
& mu; M MoO4. The applications were made twice a week
as stress application and only once a week as nutrient
solution. In each case 25 ml was added. The drought
application was carried out using 12.5 ml according to the
soil susceptibility, while the nutrient solution and 25 ml
were applied on the control group. All applications were
carried out for 5 weeks.
Figure 1 The siyez seeds were planted in the plastic pots (left). The development of the siyez seedlings under laboratory
conditions (right)
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
600
Figure 2 The growing siyez seeding treated with different amount salt, heavy metals, drought, CaCO3 and pollutant
were kept in the incubators for 5 weeks
Chemical Analyses
The leaf samples were collected at the end of the fifth
week and analysed for photosynthetic pigments
(chlorophyll- a, chlorophyll-b and carotenoids), proline,
total soluble protein, glucose, sucrose, total soluble sugar,
peroxidation level (MDA-malondialdehyde), hydrogen
peroxide (H2O2) and antioxidants such as ascorbate
peroxidase (APX), catalase (CAT) and superoxide
dismutase (SOD) activities. Analyses were carried out in
triplicate. Chlorophyll content of the leaf sample was
measured by the method of Arnon (1949). For this, 500 mg
of leaf samples were extracted with 80% acetone and
centrifuged at 3000 rpm for 15 minutes. The extract was
utilized for chlorophyll estimation. Carotenoid amount was
estimated by Jaspars Formula according to the method by
Witham et al. (1971). Proline content of leaf tissues was
estimated spectrophotometrically following the ninhydrin
method described by Bates et al. (1973). 500 mg of leaf
sample were homogenized in 3% of sulphosalicylic acid.
Samples were mixed, centrifuged at 10.000 ×g for 15 min,
and added on the supernatants 2 mm glacial acetic acid and
ninhydrin reagent 83% (w/v) ninhydrin in 60% (v/v) 6 M
phosphoric acid) in order. All samples were kept at at 90°C
for 1 h. After icecooling, 4 ml cooling toluene poured on
the samples, and then the absorbance of the upper (toluene)
phase was determined at 520 nm against a zerotime blank.
Proline concentrations were calculated using proline
standards (0-100 µg mL-1) in identical manner. The level
of lipid peroxidation products was determined using the
thiobarbioturic (TBA) method which decompose and
product of peroxidized polyunsaturated fatty acid
component of membrane lipids.500 mg sample were
homogenized in 5 ml 0.1% (w/v) trichloroacetic acid
(TCA) using a chilled mortar and pestle. The homogenate
was centrifuged at 15,000 g for 15 min. To 1 ml aliquot of
supernatant, 4 ml 0.5% (w/v) thiobarbituric acid (TBA) in
20% (w/v) TCA was added. The mixture was heated at
95°C for 30 min. The mixture was then transferred to an
ice bath and centrifuged at 10,000 g for 10 min. Then the
absorbance of the supernatant was recordedat 532 nm. The
value for nonspecific absorption at 600 nm was subtracted.
MDA content was expressed as µmol g-1 of MDA formed
using an extinction coefficient of 155 mM-1 cm-1 as µmol
MDA according to Lutts et al. (1996). Hydrogen peroxide
in the plant samples was determined by the method of
Velikova et al. (2000). 500 mg of fresh leaf samples were
homogenized with 5 mL of 0.1% (w/v) trichloroacetic acid
and then centrifuged at 12,000 g for 15 minutes. Later, 0.5
mL of 10 mM potassium phosphate buffer (pH 7.0) and 1
mL of 1 M potassium iodide were added to 0.5 mL of the
supernatant. Finally, the absorbance was recorded at 390
nm. The amount of H2O2 expressed as μmol g–1 FW. For
the determination of the enzyme activity, the extracts were
prepared from the first three leaves of the plants which
were treated as the control and the stress factor.
Accordingly, nearly 0.5-gram fresh leaf samples were
homogenized with 50 mM (pH 7.6) phosphate (P) buffer
solution (10 mL) ground in liquid nitrogen and containing
0.1 mM Na-EDTA. The homogenized samples were
centrifuged for 15 min at 15000 g and +4°C, and then the
enzyme activities in the resulting supernatant were
determined according to the methods of Çakmak (1994).
Catalase (CAT), ascorbate peroxidase (APX), guaiacol
peroxidase (GPOX) and superoxide dismutase (SOD)
activities were measured according to the methods of
Bergmeyer and Grabl (1983), Nakano and Asada
(1981), Chance and Maehley (1995) and Çakmak (1994)
respectively under nitro blue tetrazolium chloride (NBT)
light by 02- reduction. Total soluble protein contents were
determined according to the method of Bradford (1976)
using the Bio-Rad assay kit with bovine serum albumin as
a calibration standard.
Relative water content in the leaves (RWC) was
determined by the method of Ekanayake et al. (1993). The
fresh leaf samples were cut about 5 cm2 with the scissors
and weighted (FW). Then samples were placed in tube
contain 50 ml distilled water and kept at +4°C for 24 h.
Turgid weight (TW) were determined at the end of this
period and then samples were dried at 65°C for 24 h in an
oven. Dry weight of the leaf discs was recorded (DW), and
RWC of the controls and the stressed seedling was
calculated using the equation (1).
RWC (%) = [(FW-DW) / (TW-DW)] × 100 (1)
Statistical Analysis of Data
Analysis of variance (ANOVA) was applied for
analysing the differences in the chemical composition of
Siyez wheat between the different treatments and the
controls using the SPSS program (Version 20 for
Windows). Following the results of ANOVAs, Tukey’s
honestly significance difference (HSD) test (α = 0.05) was
used for significance.
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
601
Results
Mean chlorophyll-a, chlorophyll-b, total chlorophyll,
total carotenoid, relative water content and the ratio of
chlorophyll a/b in the siyez seedlings treated with the
different salts, heavy metals, drought and pollutant were
shown in Table 1. All photosynthetic pigments and relative
water content varied significantly with all treatments
(P<0.01). Mean chlorophyll-a content was lowest in the
siyez seedlings treated with the NiCl2, 75 mM salt and the
control samples (0.592, 0.603 and 0.604 mg/g
respectively), whereas it was highest in the siyez seedlings
treated with the pollution (0.691 mg/g). The control siyez
seedling showed the lowest mean chlorophyll-b, total
chlorophyll, total carotenoid and relative water content
compared to the all treatments (Table 1). Both mean
chlorophyll-b and total chlorophyll concentrations were,
however, highest with the 75 mM salt application, mean
total carotenoids was highest with the drought treatment
and mean relative water content was highest with the NiCl2
application (Table 1). The ratio of chlorophyll a/b was also
highest in the siyez seedling treated with the NiCl2, while
the highest ratio of chlorophyll a/b was noted with the
control siyez seedling. Mean MDA, H2O2, proline and total
soluble protein contents in the siyez seedlings treated with
the different salts, heavy metals, drought and pollutant
were shown in Table 2. All MDA, H2O2, proline and total
soluble protein contents varied significantly with all
treatments (P<0.01). Mean MDA and H2O2 contents were
highest in the siyez seedlings treated with the 225 mM salt,
whereas they were lowest with the NiCl2 treatment (Table
2). However, prolin content was highest with the NiCl2
treatment (103 µmol/g) compared to the lowest content in
the control siyez seedlings (82 µmol/g). Protein content
was lowest (9.04 mg/g) with the 225 mM salt application,
but it was highest 75 mM salt application (14.7 mg/g)
(Table 2). Mean APX, CAT, GPOX and SOD activities in
the siyez seedlings treated with the different salts, heavy
metals, drought and pollutant were shown in Table 3. All
APX, CAT, GPOX and SOD activities varied significantly
with all treatments (P<0.01). Mean APX, CAT and GPOX
activities were highest (0.150, 0.042 and 0.052 EU
respectively) in the siyez seedlings treated with the NiCl2,
whereas they were lowest with the 225 mM salt treatment
(0.055, 0.023 and 0.029 EU respectively). SOD activity
was also lowest (89.5 EU) with the 225 mM salt
application, but it was highest 75 mM salt application
(122.4 EU). Significant differences have been found
between the element amounts in the factory dust.
Especially the elements such as zinc, iron, chlorine,
bismuth, aluminum, lead, arsenic and boron are toxic
(Table 4).
Table 1 Mean chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoids, relative water content (RWC) and the ratio of
chlorophyll a/b in the siyez seedlings treated with the different salt contents (75, 150 and 225 mM NaCl), heavy metals
(0.2 mg/L FeCl3, NiCl2 and ZnCl2), lime (2 mg/L CaCO3), drought (50%) and pollution (0.2 mg/L dust of factories)
Chlorophyll a
mg/g
Chlorophyll b
mg/g
Total Chloropgyll
mg/g
Ratio of Chl.
a/ b
Total Carotenoids
mg/g
RWC
(%)
Control
0.604±0.003c*
0.264±0.004a
0.868±0.004a
2.29:1
7.31±0.052a
82.4±0.23b
75 mM
0.603±0.002c
0.656±0.004i
1.259±0.006f
0.92:1
8.16±0.021b
90.6±0.31c
150 mM
0.610±0.003e
0.576±0.010h
1.186±0.0113
1.06:1
8.12±0.006b
81.9±0.18a
225 mM
0.614±0.001f
0.503±0.002e
1.117±0.002c
1.22:1
8.15±0.004b
87.1±0.44c
FeCl3
0.618±0.001f
0.541±0.003f
1.158±0.003c
1.14:1
8.25±0.047b
92.3±0.34d
NiCl2
0.592±0.001a
0.277±0.010b
0.869±0.010a
2.14:1
8.11±0.014b
105.7±0.16e
ZnCl2
0.607±0.004d
0.569±0.015g
1.175±0.015d
1.07:1
8.24±0.048b
102.5±0.18e
CaCO3
0.596±0.007b
0.327±0.001c
0.922±0.007b
1.84:1
7.92±0.027a
92.7±0.67d
Drought
0.617±0.004f
0.570±0.007g
1.188±0.004e
1.09:1
8.49±0.010c
93.4±0.9d
Pollution
0.691±0.001g
0.483±0.001d
1.101±0.001b
1.28:1
8.34±0.038b
93.3±0.51
F
9.053
391.132
378.014
284.211
101.186
269.95
Sig.
0.002
0.001
0.002
0.001
0.002
0.001
*: a,b,c…i = means within the same column with different superscripts are significantly (P<0.05) different.
Table 2 Mean MDA, H2O2, proline and total soluble protein contents in the siyez seedlings treated with the different salt
contents (75, 150 and 225 mM NaCl), heavy metals (0.2 mg/L FeCl3, NiCl2 and ZnCl2), lime (2 mg/L CaCO3), drought
(50%) and pollution (0.2 mg/L dust of factories)
MDA µmol/g
H2O2 µmol/g
Prolin µmol/g
Protein mg/g
Control
18.5±0.24c*
31.6±0.22d
82.1±0.24b
10.6±0.01b
75 mM
15.5±0.23b
23.8±0.11c
93.2±0.16e
14.7±0.22d
150 mM
22.4±0.2d
34.9±0.14e
77.3±0.18a
10.4±0.01b
225 mM
26.6±0.2e
45.5±0.17f
94.5±0.21e
9.04±0.001a
FeCl3
15.5±0.06b
16.8±0.12b
97.4±0.22f
9.90±0.01a
NiCl2
12.6±0.20a
13.7±0.22a
103.6±0.21g
11.8±0.01c
ZnCl2
24.0±0.06d
17.5±0.21b
88.5±0.14c
10.8±0.01b
CaCO3
14.4±0.03b
36.4±0.11e
92.8±0.24d
10.1±0.01a
Drought
14.6±0.20b
16.4±0.19b
92.6±0.16d
10.5±0.01b
Pollution
25.8±0.16e
22.7±0.14c
93.5±0.17e
10.7±0.01b
F
893.481
4107.948
1469.364
462.087
Sig.
0.003
0.003
0.001
0.002
*: a,b,c…i = means within the same column with different superscripts are significantly (P<0.05) different
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
602
Table 3 Mean APX, CAT, GPOX and SOD activities in the siyez seedlings treated with the different salt contents (75,
150 and 225 mM NaCl), heavy metals (0.2 mg/L FeCl3, NiCl2 and ZnCl2), lime (2 mg/L CaCO3), drought (50%) and
pollution (0.2 mg/L dust of factories)
*: a,b,c…i = means within the same column with different superscripts are significantly (P<0.05) different
Discussion
Chlorophyll pigments play an important role in
photosynthetic metabolism and it they have been
considered as one of the parameters of stress tolerance in
crop plants (Panda et al. 2013; Şevik et al., 2015). In this
present study, a significant variation in the pigment
contents, especially chlorophyll-b and total chlorophyll
was observed. Mean chlorophyll-a content was highest in
the siyez seedlings treated with the pollution (0.691 mg/g),
while mean chlorophyll-b and total chlorophyll
concentrations were highest with the 75 mM salt
application (Table 2). Other studies have also revealed that
salinity, heavy metals, lime, drought, pollution and other
stress conditions can cause significant reduction in the
photosynthetic pigment level in some susceptible species.
Langmeier et al., (1993), Torun et al. (2017) expressed that
the amount of chlorophyll pigment in sensitivity plants was
lowered by heavy metals such as Ni, Cd, Zn, Fe and Hg.
Çakmak et al., (2000) and Gruber and Kosegarten (2002)
found that calcareous soil decreased pigment content and
non-chlorotic area in durum wheat genotypes Chernane et
al. (2015) showed that chlorophyll a content was lower
under salt condition, while total chlorophyll level was
higher in the control seedling compared to the stressed
seedlings. Some authors (Parida et al., 2007) showed that
photosynthetic pigments were altered under drought
conditions for wheat genotypes and cotton plants. Many
authors reported that the amount of pigments decreased
when a plant species was exposed to salt, excess heavy
metals and deficient of nutrition elements, drought and
lime stresses (Bavaresco et al., 1994; Parida et al., 2007).
They have stated that abiotic stress conditions can cause
leaf senescence by loss of chlorophyll, destruction of
chloroplast membrane and accumulation of excess free
radicals (Molas, 2002; Gregersen at al., 2008 Konuşkan et
al., 2017)). Changes in relative water content has been used
as an indicator of phytotoxicity under drought, salty, excess
heavy metal stress, deficient of nutrition and calcareous
conditions for herbal plants. In this present study, percent
relative water content was lowest in the siyez seedlings
treated with 150 mM NaCl, but highest in the siyez
seedlings treated with NiCl2 and ZnCl2 (Table 1). It has
been shown by a number of authors (Kadıoğlu and Terzi,
2007; Keyvan, 2010) that salinity, drought, heavy metals,
ion toxicity, pollution damaged water relations and
osmotic balance stress lead to decline in plant growth and
development. On the other hand, plants may prevent the
harmful effect of imbalance osmotic adjustment by
accumulation osmolytes such as proline, soluble protein,
and reduced sugars. Zhu (2002) and Farouk (2011) showed
that salt condition induced reduction in relative water
content as well as water and osmotic potential but tolerant
wheat genotypes increased osmolytes synthesis and
regulated water relation. Hui et al. (2012) and Keyvan
(2010) found that leaf relative water content decreased with
drought stress but it was higher in some genotypes due to
accumulating osmoprotective compounds. Carvajal et al.
(1996) and Gajewska et al. (2006) for wheat genotypes,
Cseh et al. (2000) for cucumber and Llamas et al. (2000)
for rice showed that the amount of relative water content
was reduced insufficient of nutrient and heavy metals such
as Pb and Ni. They stated that the stress induced stomata
closure by direct interaction of toxic metals with guard
cells and preventing of water movement water into the
vascular system. During plant growth and development,
membrane properties and compositions can change by cell
dividing, new tissues and organs forming (Berger et al.,
2001). But under stress conditions, chemical bound in
membrane lipids can be loosen by enzymatically or non-
enzymatically and stimulate toxic molecules such as
malondialdehyde (MDA), ketones and also accumulate
free radicals like singlet oxygen, hydrogen peroxide and
super oxide anions (Terzı and Kadıoglu, 2006). However,
it has been reported that the synthesis of enzymatic and
non-enzymatic antioxidant compounds increased in
tolerant crops (Ashram et al., 2007). In stressed leaf
sample, our results showed that the amount of MDA was
highest the siyez seedlings treated with the 225 mM salt,
pollution and ZnCl2, whereas it was lowest under the
drought, CaCO3 and NiCl2 conditions (Table 2). H2O2
concentration in the siyez seedlings was lowest under the
heavy metals and drought stress, but it significantly
increased in the siyez seedlings under 225 mM NaCl and
pollution condition compared to the control siyez seedlings
(Table 2).
APX
EU/mg Protein
CAT
EU/mg Protein
GPOX
EU/mg Protein
SOD
EU/mg Protein
Control
0.112±0.0001f*
0.028±0.0002d
0.046±0.0005e
104.1±0.01b
75 mM
0.090±0.0008d
0.034±0.0002e
0.036±0.0002c
122.6±0.45g
150 mM
0.076±0.0002b
0.024±0.0005b
0.032±0.0001b
109.5±0.01c
225 mM
0.055±0.0002a
0.023±0.0001a
0.029±0.0002a
89.5±0.34a
FeCl3
0.137±0.0015g
0.034±0.0003e
0.049±0.0003f
110.6±0.01d
NiCl2
0.150±0.0022h
0.042±0.0002h
0.052±0.0003g
117.7±0.43f
ZnCl2
0.089±0.0012d
0.036±0.0002g
0.042±0.0003d
118.3±0.01f
CaCO3
0.106±0.0018e
0.026±0.0003c
0.047±0.0003f
122.3±0.04g
Drought
0.138±0.0019g
0.043±0.0003i
0.049±0.0002f
117.0±0.01f
Pollution
0.085±0.0013c
0.035±0.0002f
0.042±0.0001d
114.5±0.34e
F
523.717
1064.885
953.660
4835.953
Sig.
0.003
0.002
0.002
0.001
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
603
Table 4 Mean elemental profile of dust factories
ppm
Na
55.92±0.240
Mg
47.89±0.003
Al
357.35±0.001
Si
2033.22±0.001
P
81.48±0.001
S
3029.48±0.010
Cl
35324.00±0.003
K
644.28±0.003
Ca
4906.27±0.007
Ti
279.01±0.002
V
71.20±0.001
Cr
20.42±0.001
Mn
2615.91±0.001
Fe
73377.60±0.020
Ni
29.55±0.001
Cu
61.83±0.001
Zn
85577.80±0.010
Ga
95.86±0.001
As
319.42±0.003
Br
1548.83±0.001
Rb
295.19±0.001
Sr
319.98±0.001
Y
52.93±0.001
Cd
22.11±0.001
Sn
49.91±0.001
I
60.50±0.001
Ba
329.88±0.001
Ta
29.97±0.001
Tl
58.93±0.001
Pb
10691.40±0.003
Bi
2151.08±0.001
Antioxidant enzyme activities were higher at FeCl3,
NiCl2 and drought generally (Table 3). However, CAT was
higher under heavy metals, drought and pollution
conditions, while APX increased under FeCl3, NiCl2 and
drought conditions. Mean GPOX activity was stimulated
by FeCl3, drought and NiCl2 conditions, while SOD
activity decreased with the application of 225 mM NaCl
(Table 3). The increase of MDA and H2O2 concentrations
and the reduction of APX, CAT, GPOX and SOD activities
under higher salt (225 and 150 mM NaCl), pollution and
ZnCl2 conditions indicated that there was a negative
interaction between MDA and H2O2 levels and antioxidant
enzymes (Verma and Dubey, 2003). Sairam et al. (2005)
and Abd-Elgawad et al. (2016) observed that under salt
stress, MDA and H2O2 level increased in the susceptible
wheat genotypes but antioxidant activity was higher in the
resistant types. Neto et all. (2006) also found that MDA
and H2O2 increased with salts treatments in sensitive maize
leaf and root cells, whereas SOD, CAT, APX contents were
significantly greater in tolerant types than sensitive ones. It
was reported for cereals that excess heavy metals and
pollutions induced lipid peroxidation and H2O2
accumulation, but moderate concentrations of heavy
metals and pollutions increased SOD (Verma and Dubey,
2003; Sharmila and Saradhi, 2002). Similarly, under the
drought conditions, APX, SOD and GPOX activity
increased in tolerant genotypes, but MDA and ROS levels
decreased (Mohammadi et al., 2011; Sun et al., 2016).
Jakovljević et al. (2017) investigated the salt stress on
antioxidant enzyme for the early growth in sweet basil
seedlings. Their results showed that guaiacol peroxidase
(GPOX) activity increased, but CAT activity was seen to
be the most salinity-sensitive enzyme examined. Under
calcareous stress, Shukry et al. (2007) found that there was
a decrease in photosynthetic pigments, but phenol, lipid
peroxidation, CAT, SOD and POX activities increased.
Gruben and Kosegarten (2002), Bavaresco and Poni (2002)
have stated that calcareous soils induce iron deficiency and
inhibition of enzymes activities responsible chlorophyll
synthesis in plants which are characterized as chlorosis by
Mg lacking. In many plants, osmolytes such as free proline,
glycinebetain, and soluble protein, accumulates in
response to abiotic and biotic stress conditions (Ashram et
al., 2007; Xu et al. 2012). The results from this present
study showed that mean proline content in the siyez
seedlings was higher than the control seedling. It only
decreased with the application of 225 mM NaCl. Total
soluble protein content was however reduced under all salt
applications, CaCO3 and drought conditions (Table 2).
Those findings for proline and protein were in agreement
with other studies. An increase in proline amount due to
the drought stress was reported by Keyyvan (2010),
Giancarla et al. (2011). Terzi and Yıldız (2013) and
Turkyılmaz et al. (2014) found that proline level increased
in tolerant genotypes under salty conditions. Effects of
heavy metals on proline content were studied by many
researchers. For example, Kao et al. (2007) and Gajewska
et al. (2006) showed that Ni treatments increasd proline
level in the stressed seedlings due to protein hydrolysis, a
reduce in proline dehydrogenase activity and a decrease in
proline utilization. Zengin and Kirbag (2007) found for
sunflower seedlings, a decrease in protein content with
increasing copper (Cu) concentration, but an increase in
prolin accumulation. They explained that the effect of Cu
on proline and protein contents weres dose-depended.
Under alkali and calcareous conditions, Gruber and
Kosegarten (2009) and Yang et al. (2007) observed that
prolin enhanced tolerance capacity of plants. It has been
shown that the level of soluble protein was higher in
resistant species under salt stress (Davies, 1987; Crawford,
1995) and drought conditions (Habibi, 2014; Parida et al.,
2009) and also heavy metals or lacking of minerals (Chen
et al., 2001; Singh and Tewari, 2003). The accumulations
of compatible solutes, such as proline and soluble proteins
are considered as one of the main factors responsible for
their tolerance to abiotic stress. They prevent cellular
structures and components by scavenging ROS level, and
also proteins can catabolize to proline and its content can
decrease. The results have shown that abiotic factors, in
this present study salts, heavy metals, drought, pollution
and calcareous factors can significantly influence the
photosynthetic pigments as chlorophyll-a, chlorophyll-b,
total chlorophyll and carotenoid concentrations, RWC,
proline and soluble protein concentrations, lipid
peroxidation, hydrogen peroxide, and antioxidant activities
such as APX, CAT, GPOX and SOD activities in Siyez
seedlings. Some of those chemical compounds in Siyez
cultivar could be ascribed to determine the effects of salt,
heavy meals, drought and calcareous stresses on the
resistance mechanisms of wheat genotypes. For example,
the results from the pigment analyses have also shown that
Turfan and Sarıyıldız / Turkish Journal of Agriculture - Food Science and Technology, 7(4): 598-605, 2019
604
siyez seedlings are highly resistant to FeCl3 and drought.
But based on the others results it is more tolerant to NiCl2,
75 Mm NaCl as well as FeCl3. According to all results, it
is concluded that the resistance of a plant species against
abiotic stress is not uniform and it varies with the stress
types and its concentrations.
Acknowledgement
This study has been carried out by virtue of the
assistance provided through the of KUBAP-01 / 2013-17
project.
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