TY  - JOUR
A1  - Du, Baoguo
A1  - Ma, Yuhua
A1  - Yáñez‐Serrano, Ana Maria
A1  - Arab, Leila
A1  - Fasbender, Lukas
A1  - Alfarraj, Saleh
A1  - Albasher, Gadah
A1  - Hedrich, Rainer
A1  - White, Philip J.
A1  - Werner, Christiane
A1  - Rennenberg, Heinz
T1  - Physiological responses of date palm (Phoenix dactylifera) seedlings to seawater and flooding
JF  - New Phytologist
N2  - In their natural environment along coast lines, date palms are exposed to seawater inundation and, hence, combined stress by salinity and flooding.

To elucidate the consequences of this combined stress on foliar gas exchange and metabolite abundances in leaves and roots, date palm seedlings were exposed to flooding with seawater and its major constituents under controlled conditions.

Seawater flooding significantly reduced CO\(_{2}\) assimilation, transpiration and stomatal conductance, but did not affect isoprene emission. A similar effect was observed upon NaCl exposure. By contrast, flooding with distilled water or MgSO\(_{4}\) did not affect CO\(_{2}\)/H\(_{2}\)O gas exchange or stomatal conductance significantly, indicating that neither flooding itself, nor seawater sulfate, contributed greatly to stomatal closure. Seawater exposure increased Na and Cl contents in leaves and roots, but did not affect sulfate contents significantly. Metabolite analyses revealed reduced abundances of foliar compatible solutes, such as sugars and sugar alcohols, whereas nitrogen compounds accumulated in roots.

Reduced transpiration upon seawater exposure may contribute to controlling the movement of toxic ions to leaves and, therefore, can be seen as a mechanism to cope with salinity. The present results indicate that date palm seedlings are tolerant towards seawater exposure to some extent, and highly tolerant to flooding.
KW  - compatible solutes and other metabolites
KW  - date palm
KW  - flooding
KW  - salinity
KW  - shoot–root interaction
KW  - stomatal conductance
KW  - sulfate
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228226
VL  - 229
IS  - 6
SP  - 3318
EP  - 3329
ER  - 
TY  - JOUR
A1  - Ghirardo, Andrea
A1  - Nosenko, Tetyana
A1  - Kreuzwieser, Jürgen
A1  - Winkler, J. Barbro
A1  - Kruse, Jörg
A1  - Albert, Andreas
A1  - Merl-Pham, Juliane
A1  - Lux, Thomas
A1  - Ache, Peter
A1  - Zimmer, Ina
A1  - Alfarraj, Saleh
A1  - Mayer, Klaus F. X.
A1  - Hedrich, Rainer
A1  - Rennenberg, Heinz
A1  - Schnitzler, Jörg-Peter
T1  - Protein expression plasticity contributes to heat and drought tolerance of date palm
JF  - Oecologia
N2  - Climate change is increasing the frequency and intensity of warming and drought periods around the globe, currently representing a threat to many plant species. Understanding the resistance and resilience of plants to climate change is, therefore, urgently needed. As date palm (Phoenix dactylifera) evolved adaptation mechanisms to a xeric environment and can tolerate large diurnal and seasonal temperature fluctuations, we studied the protein expression changes in leaves, volatile organic compound emissions, and photosynthesis in response to variable growth temperatures and soil water deprivation. Plants were grown under controlled environmental conditions of simulated Saudi Arabian summer and winter climates challenged with drought stress. We show that date palm is able to counteract the harsh conditions of the Arabian Peninsula by adjusting the abundances of proteins related to the photosynthetic machinery, abiotic stress and secondary metabolism. Under summer climate and water deprivation, these adjustments included efficient protein expression response mediated by heat shock proteins and the antioxidant system to counteract reactive oxygen species formation. Proteins related to secondary metabolism were downregulated, except for the P. dactylifera isoprene synthase (PdIspS), which was strongly upregulated in response to summer climate and drought. This study reports, for the first time, the identification and functional characterization of the gene encoding for PdIspS, allowing future analysis of isoprene functions in date palm under extreme environments. Overall, the current study shows that reprogramming of the leaf protein profiles confers the date palm heat- and drought tolerance. We conclude that the protein plasticity of date palm is an important mechanism of molecular adaptation to environmental fluctuations.
KW  - abiotic stress
KW  - isoprene
KW  - proteomics
KW  - photosynthesis
KW  - Phoenix dactylifera
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-308075
SN  - 0029-8549
SN  - 1432-1939
VL  - 197
IS  - 4
ER  -