Book of Abstracts - Geyseco

P - Posters
key chloroplast components, such as chlorophyll a, carotenoids
and D1 protein, which in turn helped to maintain a higher PSII
photochemical efficiency under strong oxidative treatments. In
addition, CuHP caused in TR1 a higher decrease of non-photochemical
dissipation of energy (NPQ) and also diminished the
activity of key antioxidant enzymes, like SOD, GR and APx,
while in TR9 a lesser NPQ decrease and a significant increase of
antioxidant enzymes were observed. We propose that the constant
presence of TR1 and TR9 in every R. farinacea thalli could
be favoured by the different and probably complementary physiological
behaviour of each photobiont.
(Grants: CGL2009-13429-C02-00 and PROMETEO 174/2008
GVA)
P01-042: RESPONSES OF TRANSGENIC TOBACCO
PLANTS WITH INCREASED PROLINE CONTENT TO
WATER AND/OR HEAT STRESS
Pospisilova, J.* - Haisel, D. - Vankova, R.
Institute of Experimental Botany, Academy of Sciences of the
Czech Republic, Prague
*Corresponding author, e-mail: pospisilova@ueb.cas.cz
Net photosynthetic rate, transpiration rate, stomatal conductance
and pigment contents in transgenic tobacco plants (M51-1)
constitutively over-expressing a modified gene for the proline
biosynthetic enzyme ∆2-pyrroline-5-carboxylate synthetase
(P5CSF129A) and the corresponding wild-type plants (WT)
were compared during water stress and heat stress alone or in
combination. The proline content was several times higher in
M51-1 than in WT which coincided with abscisic acid content
higher in transformant. In non-stressed plants, transpiration rate
and stomatal conductance of M51-1 were lower than those of
WT, while differences in net photosynthetic rate were not significant
and water use efficiency and contents of chlorophyll and
xanthophyll cycle pigments were higher in M51-1 than WT. Cessation
of watering for 7 d decreased all gas exchange parameters
and pigments contents, the response being similar in M51-1 and
WT plants. After heat stress (40 °C/60 min) applied to control
or water-stressed plants the gas exchange parameters decreased
considerably in both M51-1 and WT plants. Short-term heat
stress alone, however, did not affect pigment contents.
P01-043: ROOT SPECIFIC EXPRESSION OF THE
TRANSCRIPTION FACTOR OSNAC10 IMPROVES
DROUGHT TOLERANCE AND GRAIN YIELD IN RICE
UNDER FIELD DROUGHT CONDITIONS
Jeong, JS. 1 * - Kim, YS. 1 - Baek, WH. 1 - Park, HK. 1 - Ha, SH. 2
- Choi, YD. 3 - Kim, M. 3 - Reuzeau, C. 4 - Kim, JK. 1
1
School of Biotechnology and Environmental Engineering,
Myongji University
2
(National Academy of Agricultural Science, RDA),
3
(School of Agricultural Biotechnology, Seoul National University)
4
(CropDesign N.V., Technologiepark ),
*Corresponding author, e-mail: jsjeong74@gmail.com
Drought poses a serious threat to the sustainability of rice yields
in rainfed agriculture. Here we report the results of a functional
genomics approach that identified a rice NAC-domain gene,
OsNAC10, which improved performance of transgenic rice plants
under field drought conditions. Of the 140 OsNAC genes predicted
in rice, 18 were identified to be induced by stress conditions.
Phylogenic analysis of the 18 OsNAC genes revealed the presence
of 3 subgroups with distinct signature motifs. The OsNAC10
is expressed predominantly in roots and panicles, and induced
by drought, high salinity and ABA. Overexpression of OsNAC10
in rice under the control of the constitutive promoter GOS2 and
the root-specific promoter RCc3 increased the plant tolerance
to drought, high salinity and cold at the vegetative stage. More
importantly, the RCc3:OsNAC10 plants showed significantly
enhanced drought tolerance at the reproductive stage, increasing
grain yield by 25-42% and 5-14% over controls in the field under
drought and normal conditions, respectively. Grain yield of
GOS2:OsNAC10 plants in the field, in contrast, remained similar
to that of controls under both normal and drought conditions.
These differences in performance under field drought conditions
reflect the difference in expression of OsNAC10-dependent target
genes in roots as well as in leaves of the two transgenic plants,
as revealed by microarray. Root diameter of the RCc3:OsNAC10
plants was thicker by 1.25-fold than that of the GOS2:OsNAC10
and NT plants due to the enlarged stele, cortex and epidermis.
Overall, our results demonstrated that root specific overexpression
of OsNAC10 enlarges roots, enhancing drought tolerance of
transgenic plants, which increases grain yield significantly under
field drought conditions.
P01-044: SALT STRESS-INDUCED CHANGES IN MITO-
CHONDRIA FROM LUPINE EMBRYO AXES
Garnczarska M 1 * - Wojtyla, L. 1 - Grabsztunowicz, M. 1 - Rog, M. 1
- osmala, A. 2
1
Department of Plant Physiology, A. Mickiewicz University, Poland
2
Insitiute of Plant Genetics, Polish Academy of Sciences, Poland
*Corresponding author, e-mail: garnczar@amu.edu.pl
In this work, an attempt was made to investigate the response of
mitochondria from lupine (Lupinus luteus) embryo axes to salinity
stress. Changes in mitochondria from isolated lupine embryo
axes grown on modified Heller medium with or without addition
of 0,1M NaCl for 24, 48 and 72 h were analysed. 2D-IEF-PAGE
electrophoresis of mitochondria proteins revealed that after 24
hours 38% of proteins had lower and 27% higher level of expression
in salt treated axes as compared to control. After 48 and 72
hours approximately 33% of proteins were both less and more
abundant in salt stressed organs than in non-stressed. The profile
of antioxidant enzymes was also analysed. Native electrophoresis
of mitochondrial proteins revealed higher activity of catalase
and superoxide dismutase in mitochondria from salt treated axes
in comparison with control axes. Salt stress caused ultrastructural
changes of ER but no deformation of mitochondria was observed.
We have also established a salt-induced PCD model in lupine
embryo axes. Our results indicated that NaCl treatment lead
to specific characteristic of PCD in lupine embryo axes, such as
DNA laddering and cytochrome c release from mitochondria into
the cytoplasm. Changes in mitochondrial proteome during saltinduced
PCD were also studied.
This work was partially supported by Polish Ministry of Science
and Higher Education research grant N N303 471038.
P01-045: ROLE OF SILICON IN MITIGATION OF CAD-
MIUM TOXICITY IN MAIZE
Vaculik, M. 1 * - Lux, A. 1 - Luxova, M. 2 - Tanimoto, E. 3 - Lichtscheidl,
I. 4
1
Department of Plant Physiology, Faculty of Natural Sciences,
Comenius University in Bratislava
2
Institute of Botany, Slovak Academy of Sciences, Bratislava,
Slovakia
3
Department of Information and Biological Sciences, Graduate
School of Natural Sciences, Nagoya City University, Mizuho,
Japan
4
Cell Imaging and Ultrastructure Research, University of Vienna,
Austria
*Corresponding author, e-mail: vaculik@fns.uniba.sk
Silicon, the second most abundant element in the earth crust, is
not considered as an essential element in general, but its beneficial
influence in alleviation of various kinds of abiotic and biotic
stresses in plants is known. Recently, several studies described
Si-induced alleviation of negative effects of dangerous toxic
metal cadmium on plants, but the role of Si in this process is
poorly understood. This contribution brings novel insight into
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