response of quercus cerris to combined ozone and drought...
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Response of Quercus cerris to combined ozone and drought stress
Cotrozzi L., Remorini D., Pellegrini E., Lorenzini G., Massai R., Nali C. Department of Agriculture, Food and Environment
University of Pisa E-mail: [email protected]
Paris, 30th January 2014
27th Task Force Meeting of the ICP Vegetation
&
One-day ozone workshop
Urban forests
• Trees are essential in the urban environment:
–Aesthetic values – Social values – Effects on air quality
• Interaction between climate change and urban forests: – Adjusting the urban forests to change – Using urban forests to help cities to adapt to change
Monitoring of Mediterranean plants health is necessary
2050 scenario: 1) Surface air temperature; 2) Heat waves; 3) Background O3; 4) Atmospheric CO2; 5) Drought events
Guidi L., Calatayud A., 2013. Non-invasive tools to estimate stress-induced changes in photosynthetic performance in plants inhabiting Mediterranean areas. Environmental and Experimental Botany . In press
• Gas exchanges • Chlorophyll a fluorescence
Non-invasive Rapid Inexpensive
Aim of the work
• Physiological and biochemical responses of the Mediterranean deciduous
Quercus cerris to combined stress (ozone and drought)
in controlled environments to simulate a 2050 global climate change
scenario
(little is known about ozone and drought stresses in Q. cerris, frequent in Italian urban
areas)
• Combination of ozone and drought = ozone and drought applied individually?
Materials and methods • June-August 2013 (11 weeks)
• Four exposure chambers:
1. Control
2. Drought stress
3. Ozone stress
4. Combined stress
• O3 concentration: 80-100 ppb, 5 h d-1
• Drought stress: 30% of effective evapotranspiration
PHYSIOLOGICAL ANALYSES: •Gas exchanges
•Chlorophyll a fluorescence •Predawn leaf water potential
•Growth parameters and biomass partitioning
BIOCHEMICAL ANALYSES: •Lipid peroxidation (MDA)
•Proline
Gas-exchanges (weekly profile)
Control
A (
mm
ol C
O2 m
-2 s
-1)
0
4
8
12
16
Drought stress Ozone stress Combined stress
g s (
mol H
2O
m-2
s-1)
0.0
0.1
0.2
0.3
0.4
Days
14 21 28 35 42 49 56 63 70 77
Ci (
ppm
)
0
100
200
300
400
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
aab
fg ef cde
gh
f def
hi
ef
pqop
lm
op
lm
qrp pq
r qr
op
hijlm
jkkl lmn
mn
ijk
no
ijk
def
a
def def
bccd
ef def
hij
def
mn lm
f-lklm
e-k
oo o
n n
d-i d-h
abc
a-e
a
a-dd-i
b-g
klm
a-f
h-lh-l d-j g-l
d-ii-l
klmklm
h-lj-m
d-i b-g
ab aba
a-fd-j
d-if-k
c-g
aab
bcc c
cdcdedefefgefge-h
f-i f-jf-k
f-kg-kg-l
h-mh-m
i-n i-oj-o k-pl-q l-ql-ql-q
m-q
n-qn-qn-q opqpqr pqr pqrqrqr
r
s
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time ***
Treatment **
Time ***
Treatment × Time ***
e-h
Visible injury
Gas-exchanges (weekly profile)
Control
A (
mm
ol C
O2 m
-2 s
-1)
0
4
8
12
16
Drought stress Ozone stress Combined stress
g s (
mol H
2O
m-2
s-1)
0.0
0.1
0.2
0.3
0.4
Days
14 21 28 35 42 49 56 63 70 77
Ci (
ppm
)
0
100
200
300
400
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
aab
fg ef cde
gh
f def
hi
ef
pqop
lm
op
lm
qrp pq
r qr
op
hijlm
jkkl lmn
mn
ijk
no
ijk
def
a
def def
bccd
ef def
hij
def
mn lm
f-lklm
e-k
oo o
n n
d-i d-h
abc
a-e
a
a-dd-i
b-g
klm
a-f
h-lh-l d-j g-l
d-ii-l
klmklm
h-lj-m
d-i b-g
ab aba
a-fd-j
d-if-k
c-g
aab
bcc c
cdcdedefefgefge-h
f-i f-jf-k
f-kg-kg-l
h-mh-m
i-n i-oj-o k-pl-q l-ql-ql-q
m-q
n-qn-qn-q opqpqr pqr pqrqrqr
r
s
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time ***
Treatment **
Time ***
Treatment × Time ***
e-h
Visible injury
Drought stress Ozone stress Combined stress
A From the 2nd week From the 7th week From the 2nd week
- 65.3% - 25.6% - 67.9%
gs
From the 2nd week From the 7th week From the 2nd week
- 65.7% - 39.6% - 67.5%
Gas-exchanges (weekly profile)
Control
A (
mm
ol C
O2 m
-2 s
-1)
0
4
8
12
16
Drought stress Ozone stress Combined stress
g s (
mol H
2O
m-2
s-1)
0.0
0.1
0.2
0.3
0.4
Days
14 21 28 35 42 49 56 63 70 77
Ci (
ppm
)
0
100
200
300
400
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
aab
fg ef cde
gh
f def
hi
ef
pqop
lm
op
lm
qrp pq
r qr
op
hijlm
jkkl lmn
mn
ijk
no
ijk
def
a
def def
bccd
ef def
hij
def
mn lm
f-lklm
e-k
oo o
n n
d-i d-h
abc
a-e
a
a-dd-i
b-g
klm
a-f
h-lh-l d-j g-l
d-ii-l
klmklm
h-lj-m
d-i b-g
ab aba
a-fd-j
d-if-k
c-g
aab
bcc c
cdcdedefefgefge-h
f-i f-jf-k
f-kg-kg-l
h-mh-m
i-n i-oj-o k-pl-q l-ql-ql-q
m-q
n-qn-qn-q opqpqr pqr pqrqrqr
r
s
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time ***
Treatment **
Time ***
Treatment × Time ***
e-h
Visible injury
Drought stress Ozone stress Combined stress
Ci
From the 7th week From the 7th week From the 8th week
Gas-exchanges (weekly profile)
Drought stress Ozone stress Combined stress
A From the 2nd week From the 7th week From the 2nd week
- 65.3% - 25.6% - 67.9%
gs
From the 2nd week From the 7th week From the 2nd week
- 65.7% - 39.6% - 67.5%
Ci
From the 7th week From the 7th week From the 8th week
• Decrease of net photosynthesis was twinned with stomatal and mesophyllic limitation (or damage)
• Drought should be considered more harmful than ozone
• Combined stress did not show significant changes in comparison to drought stressed individuals
Gas-exchanges (circadian profile) VI week: visible injury observed
Control
A (
mm
ol C
O2 m
-2 s
-1)
0
3
6
9
12
Drought stress Ozone stress Combined stress
g s (
mol H
2O
m-2
s-1)
0.00
0.03
0.06
0.09
0.12
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Ci (
ppm
)
0
100
200
300
400
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time *
Treatment **
Time ***
Treatment × Time ***
aa
aaabab ab
abc
abcbc
cd
cdcd
de de eefef
fgghghgh
ghh
i iijj
aab
ab ab abca-da-d
a-d
a-da-db-ecdecde
deef
fggh
ghi
ghighi
hijijk jk
k klklkll
a
abbc
bc
bcbcdcde
defefge-h
e-he-he-h e-he-i
e-if-j
f-kf-k
g-lh-li-l
i-l
i-l
jklkl
kll
Gas-exchanges (circadian profile) VI week: visible injury observed
Control
A (
mm
ol
CO
2 m
-2 s
-1)
0
3
6
9
12
Drought stress Ozone stress Combined stress
Gs
(mol
H2O
m-2
s-1
)
0.00
0.03
0.06
0.09
0.12
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Ci
(ppm
)
0
100
200
300
400
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time *
Treatment **
Time ***
Treatment × Time ***
aa
aaabab ab
abc
abcbc
cd
cdcd
de de eefef
fgghghgh
ghh
i iijj
aab
ab ab abca-da-d
a-d
a-da-db-ecdecde
deef
fggh
ghi
ghighi
hijijk jk
k klklkll
a
abbc
bc
bc
bcdcdedefefg
e-he-h
e-he-h e-he-ie-i
f-jf-k
f-kg-lh-l
i-li-l
i-l
jklkl
kll
Drought stress Ozone stress Combined stress
A - 65.3% - 63.7%
Gas-exchanges (circadian profile) VI week: visible injury observed
Control
A (
mm
ol C
O2 m
-2 s
-1)
0
3
6
9
12
Drought stress Ozone stress Combined stress
g s (
mol H
2O
m-2
s-1)
0.00
0.03
0.06
0.09
0.12
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Ci (
ppm
)
0
100
200
300
400
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time *
Treatment **
Time ***
Treatment × Time ***
aa
aaabab ab
abc
abcbc
cd
cdcd
de de eefef
fgghghgh
ghh
i iijj
aab
ab ab abca-da-d
a-d
a-da-db-ecdecde
deef
fggh
ghi
ghighi
hijijk jk
k klklkll
a
abbc
bc
bcbcdcde
defefge-h
e-he-he-h e-he-i
e-if-j
f-kf-k
g-lh-li-l
i-l
i-l
jklkl
kll
Drought stress Ozone stress Combined stress
gs - 72.6% - 26.0% - 74.3%
Ci
Gas-exchanges (circadian profile)
Drought stress Ozone stress Combined stress
A - 65.3% - 63.7%
gs - 72.6% - 26.0% - 74.3%
Ci
• Drought and combined stress: decrease of net photosynthesis is twinned with stomatal and mesophyllic
limitation (or damage) • Ozone stress: stomatal closure in order to avoid the ozone
entry (exclusion) • Drought should be considered more harmful than ozone • Combined stress did not show significant changes in
comparison to drought stressed individuals
Control
Y
0.0
0.2
0.4
0.6
0.8
Drought stress Ozone stress Combined stress
qP
0.0
0.3
0.6
0.9
1.2
Treatment ***
Time ***
Treatment × Time ***
Treatment ***
Time ***
Treatment × Time ***
Days
14 21 28 35 42 49 56 63 70 77
qN
P
0.0
0.3
0.6
0.9
1.2
Treatment **
Time ***
Treatment × Time ***
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
Days
14 21 28 35 42 49 56 63 70 77
a abab
abc abca-da-da-d
a-da-d
a-da-d a-d b-e
c-fc-f c-g c-gc-h
d-i
d-je-ke-l f-mf-n f-n
g-ng-nh-n i-ni-n j-n
k-nk-ok-o
k-ol-omno noo
aa
ababc abcabc
bcdb-eb-e
c-fc-fc-f c-fd-g d-hd-i
d-jd-ke-l f-mf-n
g-oh-oi-o i-oj-o k-ol-pl-p
l-p l-pl-p m-pm-p nop opopop p
aab
abcbcd
cdec-fc-f
c-fd-g
d-gd-h d-hd-h
d-ie-j
e-ke-k
e-ke-ke-k e-k
f-k
f-k
f-kg-l
g-lg-l g-l h-lh-l
h-lh-li-l
i-ljkl
jkljkl klll
h-o
Chlorophyll a fluorescence (weekly profile)
Visible injury
Chlorophyll a fluorescence (weekly profile)
Drought stress Ozone stress Combined stress
Y From the 6th week From the 2nd week From the 6th week
- 19.6% - 25.0%
qP
From the 6th week From the 2nd week From the 6th week
- 9.4% - 20.5%
qNP
From the 4th week From the 2nd week From the 2nd week
+14,6 %
• Drought stress: photoinhibition with activation of non-photochemical mechanism, but not PSII photodamage
• Ozone stress: no effect on PSII performance • Combined stress: photoinhibition with no activation of non-photochemical mechanisms, excess energy should be dissipated by other mechanisms, not PSII
photodamage
• Fv/Fm did not show significant change during the exposure
(all plants showed values inside the optimal range)
Chlorophyll a fluorescence (circadian profile)
VI week: visible injury observed Control
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Y
0.0
0.2
0.4
0.6
0.8
Drought stress
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Ozone stress
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Combined stress
Hour
7.00
9.00
11.0
0
13.0
0
15.0
0
17.0
0
19.0
0
Treatment ***
Time ***
Treatment × Time *
a
ab bcbcdbcdbcd
b-eb-eb-e
b-ecde
cde
cde de efffffff
f f f ff
f
Drought stress Ozone stress Combined stress
Y From 7.00 From 9.00 From 7.00
- 39.9% - 41.6%
• Drought and combined stress: photoinhibition but not PSII photodamage
• Ozone stress: no effect on PSII performance
Biomass partitioning and growth parameters Growth parameters Control Drought stress Ozone stress Combined stress P
Total dry weight (g) 41.34
±11.021 b
17.92
±3.476 a
36.72
±6.471 b
18.31
±0.930 a **
Shoot/root (g g-1) 2.11
±1.013
1.40
±0.090
0.99
±0.314
1.36
±0.110 ns
Roots (g) 14.54
±2.420 ab
8.30
±2.643 a
20.16
±7.234 b
8.16
±0.075 a *
Stems (g) 17.53
±6.852 b
5.80
±0.702 a
12.09
±1.470 ab
8,08
±0.680 a *
Leaves (g) 9.27
±2.812 b
3.82
±1.551 a
4.47
±0.357 a
2.08
±0.325 a **
Leaf number 231.33
±92.230 b
65.67
±22.745 a
39.33
±11.504 a
17.50
±10.112 a **
Non-syptomatic old leaves (g) 8.74
±2.761 c
2.68
±0.605 ab
4.00
±0.897 b
0.15
±0.145 a ***
Symptomatic old leaves (g) 0.00
±0.000 a
0.93
±0.810 ab
0.00
±0.000 a
1.83
±0.570 b **
Non-symptomatic young leaves (g) 0.52
±0.051
0.21
±0.330
0.47
±0.660
0.10
±0.100 ns
• Drought and combined stress: visible at the whole plant level as reduced growth and at the organ level as leaf symptoms
• Ozone stress: reductions only in leaves
PDLWP, lipid peroxidation, proline
Week
PREDAWN LEAF WATER POTENTIAL (Mpa)
P Control Drought stress Ozone stress
Combined
stress
VI -0.5
±0.03 c
-1.4
±0.10 b
-0.4
±0.03 c
-2.9
±0,20 a ***
XI -0.5
±0.10 c
-0.9
±0.08 a
-0.6
±0.21 bc
-0.8
±0.10 ab *
Week
MALONDIALDEHYDE (nmol g-1 FDW)
P Control Drought stress Ozone stress
Combined
stress
VI 129.34
±13.196
127.36
±16.054
112.80
±7.487
130.83
±9.889 ns
XI 161.88
±10.400 a
202.76
±9.558 b
189.84
±9.002 a
210.81
±1.344 c ***
Week
PROLINE (mg g-1 FDW)
P Control Drought stress Ozone stress
Combined
stress
VI 0.09
±0.007 b
0.19
±0.016 d
0.04
±0.004 a
0.13
±0.003 c ***
XI 0.10
±0.014 a
0.13
±0.009 b
0.10
±0.006 a
0.18
±0.005 c ***
• Only drought and combined stresses
act on lipid peroxidation
• Only drought and combined stresses
reduce PDLWP
• Only drought and combined stresses act on the proline
content
In conclusion: Drought stress Ozone stress
Combined stress
Carbon dioxide assimilation rate
Stomatal limitation YES YES YES
Mesophillic limitation YES YES YES
Photodamage NO NO NO
Photoinibition YES NO YES
Non-photochemical mechanism
YES NO NO
Growth reduction YES YES
(only in leaves) YES
Leaf symptoms YES NO YES
Hydric status
Lipid peroxidation
Proline
• Drought should be considered more harmful than ozone
• Combined stress did not show significant changes in comparison to drought stressed individuals
Thank you for your kind
attention