TY  - JOUR
AB  - 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.
AU  - Ghirardo, A.
AU  - Nosenko, T.
AU  - Kreuzwieser, J.*
AU  - Winkler, J.B.
AU  - Kruse, J.*
AU  - Albert, A.
AU  - Merl-Pham, J.
AU  - Lux, T.
AU  - Ache, P.*
AU  - Zimmer, I.
AU  - Alfarraj, S.*
AU  - Mayer, K.F.X.
AU  - Hedrich, R.*
AU  - Rennenberg, H.*
AU  - Schnitzler, J.-P.
C1  - 61890
C2  - 50506
CY  - One New York Plaza, Suite 4600, New York, Ny, United States
SP  - 903–919
TI  - Protein expression plasticity contributes to heat and drought tolerance of date palm.
JO  - Oecologia
VL  - 197
PB  - Springer
PY  - 2021
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Plant isoprene emissions are known to contribute to abiotic stress tolerance, especially during episodes of high temperature and drought, and during cellular oxidative stress. Recent studies have shown that genetic transformations to add or remove isoprene emissions cause a cascade of cellular modifications that include known signaling pathways, and interact to remodel adaptive growth-defense tradeoffs. The most compelling evidence for isoprene signaling is found in the shikimate and phenylpropanoid pathways, which produce salicylic acid, alkaloids, tannins, anthocyanins, flavonols and other flavonoids; all of which have roles in stress tolerance and plant defense. Isoprene also influences key gene expression patterns in the terpenoid biosynthetic pathways, and the jasmonic acid, gibberellic acid and cytokinin signaling networks that have important roles in controlling inducible defense responses and influencing plant growth and development, particularly following defoliation. In this synthesis paper, using past studies of transgenic poplar, tobacco and Arabidopsis, we present the evidence for isoprene acting as a metabolite that coordinates aspects of cellular signaling, resulting in enhanced chemical defense during periods of climate stress, while minimizing costs to growth. This perspective represents a major shift in our thinking away from direct effects of isoprene, for example, by changing membrane properties or quenching ROS, to indirect effects, through changes in gene expression and protein abundances. Recognition of isoprene's role in the growth-defense tradeoff provides new perspectives on evolution of the trait, its contribution to plant adaptation and resilience, and the ecological niches in which it is most effective.
AU  - Monson, R.K.*
AU  - Weraduwage, S.M.*
AU  - Rosenkranz, M.
AU  - Schnitzler, J.-P.
AU  - Sharkey, T.D.*
C1  - 60987
C2  - 50005
CY  - One New York Plaza, Suite 4600, New York, Ny, United States
SP  - 885-902
TI  - Leaf isoprene emission as a trait that mediates the growth-defense tradeoff in the face of climate stress.
JO  - Oecologia
VL  - 197
IS  - 4
PB  - Springer
PY  - 2021
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination.
AU  - Allan, E.*
AU  - Weisser, W.W.*
AU  - Fischer, M.*
AU  - Schulze, E.D.*
AU  - Weigelt, A.*
AU  - Roscher, C.*
AU  - Baade, J.*
AU  - Barnard, R.L.*
AU  - Beßler, H.*
AU  - Buchmann, N.*
AU  - Ebeling, A.*
AU  - Eisenhauer, N.*
AU  - Engels, C.*
AU  - Fergus, A.J.*
AU  - Gleixner, G.*
AU  - Gubsch, M.*
AU  - Halle, S.*
AU  - Klein, A.M.*
AU  - Kertscher, I.*
AU  - Kuu, A.*
AU  - Lange, M.*
AU  - Le Roux, X.*
AU  - Meyer, S.T.*
AU  - Migunova, V.D.*
AU  - Milcu, A.*
AU  - Niklaus, P.A.*
AU  - Oelmann, Y.*
AU  - Pašalić, E.*
AU  - Petermann, J.S.*
AU  - Poly, F.*
AU  - Rottstock, T.*
AU  - Sabais, A.C.*
AU  - Scherber, C.*
AU  - Scherer-Lorenzen, M.*
AU  - Scheu, S.*
AU  - Steinbeiss, S.
AU  - Schwichtenberg, G.*
AU  - Temperton, V.*
AU  - Tscharntke, T.*
AU  - Voigt, W.*
AU  - Wilcke, W.*
AU  - Wirth, C.*
AU  - Schmid, B.*
C1  - 26070
C2  - 32054
SP  - 223-237
TI  - A comparison of the strength of biodiversity effects across multiple functions.
JO  - Oecologia
VL  - 173
IS  - 1
PB  - Springer
PY  - 2013
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - The principal function of isoprene biosynthesis in plants remains unclear, but emission rates are positively correlated with temperature and light, supporting a role for isoprene in maintaining photosynthesis under transient heat and light stress from sunflecks. Isoprene production is also inversely correlated with CO(2) concentrations, implying that rising CO(2) may reduce the functional importance of isoprene. To understand the importance of isoprene in maintaining photosynthesis during sunflecks, we used RNAi technology to suppress isoprene production in poplar seedlings and compared the responses of these transgenic plants to wild-type and empty-vector control plants. We grew isoprene-emitting and non-emitting trees at low (190 ppm) and high (590 ppm) CO(2) concentrations and compared their photosynthetic responses to short, transient periods of high light and temperature, as well as their photosynthetic thermal response at constant light. While there was little difference between emitting and non-emitting plants in their photosynthetic responses to simulated sunflecks at high CO(2), isoprene-emitting trees grown at low CO(2) had significantly greater photosynthetic sunfleck tolerance than non-emitting plants. Net photosynthesis at 42°C was 50% lower in non-emitters than in isoprene-emitting trees at low CO(2), but only 22% lower at high CO(2). Dark respiration rates were significantly higher in non-emitting poplar from low CO(2), but there was no difference between isoprene-emitting and non-emitting lines at high CO(2). We propose that isoprene biosynthesis may have evolved at low CO(2) concentrations, where its physiological effect is greatest, and that rising CO(2) will reduce the functional benefit of isoprene in the near future.
AU  - Way, D.A.*
AU  - Schnitzler, J.-P.
AU  - Monson, R.K.*
AU  - Jackson, R.B.*
C1  - 11322
C2  - 30611
SP  - 273-282
TI  - Enhanced isoprene-related tolerance of heat- and light-stressed photosynthesis at low, but not high, CO2 concentrations.
JO  - Oecologia
VL  - 166
IS  - 1
PB  - Springer
PY  - 2011
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Plants in alpine habitats are exposed to many environmental stresses, in particular temperature and radiation extremes. Recent field experiments on Arnica montana L. cv. ARBO indicated pronounced altitudinal variation in plant phenolics. Ortho-diphenolics increased with altitude compared to other phenolic compounds, resulting in an increase in antioxidative capacity of the tissues involved. Factors causing these variations were investigated by climate chamber (CC) experiments focusing on temperature and ultraviolet (UV)-B radiation. Plants of A. montana L. cv. ARBO were grown in CCs under realistic climatic and radiation regimes. Key factors temperature and UV-B radiation were altered between different groups of plants. Subsequently, flowering heads were analyzed by HPLC for their contents of flavonoids and caffeic acid derivatives. Surprisingly, increased UV-B radiation did not trigger any change in phenolic metabolites in Arnica. In contrast, a pronounced increase in the ratio of B-ring ortho-diphenolic (quercetin) compared to B-ring monophenolic (kaempferol) flavonols resulted from a decrease in temperature by 5A degrees C in the applied climate regime. In conclusion, enhanced UV-B radiation is probably not the key factor triggering shifts in the phenolic composition in Arnica grown at higher altitudes but rather temperature, which decreases with altitude.
AU  - Albert, A.
AU  - Sareedenchai, V.*
AU  - Heller, W.
AU  - Seidlitz, H.K.
AU  - Zidorn, C.*
C1  - 96
C2  - 26168
SP  - 1-8
TI  - Temperature is the key to altitudinal variation of phenolics in Arnica montana L. cv. ARBO.
JO  - Oecologia
VL  - 160
IS  - 1
PB  - Springer
PY  - 2009
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - The carbon isotope compositions of samples of Kalanchoë species collected at the natural stands in Madagascar were determined. The results suggest that all species of the genus Kalanchoë are capable of crassulacean acid metabolism. The observed δ13C values cover the whole range from -10 to -30‰. This high diversity of the δ13C values was found among the species of the genus as well as, in certain cases, within a single species. This suggest that the CAM patterns in Kalanchoë are generally very flexible. The δ13C values show a clear correlation with the climate of the habitats from where the samples derived. Values indicative of CO2 fixation taking place exclusively during the night were found in the dry regions of Madagascar, whereas δ13C values indicative of mixed CO2 fixation during night and day or of CO2 fixation entirely during the day are distributed in the humid zones.
AU  - Kluge, M.*
AU  - Brulfert, J.*
AU  - Ravelomanana, D.*
AU  - Lipp, J.
AU  - Ziegler, H.*
C1  - 40749
C2  - 38046
SP  - 407-414
TI  - Crassulacean acid metabolism in Kalanchoë species collected in various climatic zones of Madagascar: a survey by δ13C analysis.
JO  - Oecologia
VL  - 88
IS  - 3
PY  - 1991
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - This study is based both on our own results, especially δ13C analyses, and on data in the literature. Of the 225 species of Poaceae reported from Egypt, 105 species show the C3 and 120 the C4 type of photosynthetic CO2 fixation. Winter annual and perennial grasses active in winter are mainly C3 species, while summer annuals and the other perennials are mainly C4 species. The percentage of C3 species decreases with decreasing latitude. This seems to be mainly related to increasing temperatures. The C3 grass species are found preferentially in the Mediterranean, Irano-Turanian, Mediterranean/Irano-Turanian, and Saharo-Arabian chorotypes, while the C4 species are mainly found in the Sudanian, Saharo-Arabian/Sudanian and Tropical chorotypes. In Egypt, the NADP+-ME and NAD+-ME subtypes of C4 photosynthesis are found in about equal numbers of C4 species, while the PCK subtype is relatively rare.
AU  - Batanouny, K.H.*
AU  - Stichler, W.
AU  - Ziegler, H.*
C1  - 33862
C2  - 38029
SP  - 539-548
TI  - Photosynthetic pathways, distribution, and ecological characteristics of grass species in egypt.
JO  - Oecologia
VL  - 75
IS  - 4
PY  - 1988
SN  - 0029-8549
ER  - 

TY  - JOUR
AU  - Schramel, P.
AU  - Oven, R.
AU  - Schulze, E.-D.
AU  - Weck, K.S.
AU  - Meyer, S.
C1  - 17394
C2  - 10004
TI  - Performance of two Picea abies (L.) Karst stands at Different Stages of Decline. VI. Nutrient Relations and Growth.
JO  - Oecologia
PY  - 1988
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Based on the differential discrimination between 13CO2 and 12CO2 during photosynthetic CO2 fixation by C3 and C4 plants, the relative contribution of organic soil material of varying age can be checked by measuring the δ13C value of CO2 evolved during soil respiration. The CO2 from a soil cropped only with C3 plants for at least 7 years showed a δ13C value very close to that of C3 plant tissue. Correspondingly, a soil bearing the C4 plant maize for at least 6 years had a δ13C value for the respiratory CO2 quite near to that of a typical C4 plant. A soil cropped with maize in the year of study only showed intermediate δ13C values, with a tendency towards C4. With soil standardised for cultivation and cropping, a quantification of the part that fresh organic matter and especially the last year plant residues play in soil respiration, can be achieved.
AU  - Schönwitz, R.*
AU  - Stichler, W.
AU  - Ziegler, H.*
C1  - 42287
C2  - 38368
SP  - 305-308
TI  - δ13C values of CO2 from soil respiration on sites with crops of C3 and C4 type of photosynthesis.
JO  - Oecologia
VL  - 69
IS  - 2
PY  - 1986
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - According to carbon isotope ratios, species of the Sempervivoideae from Teneriffe show in general a tendency for increased participation of dark CO2 fixation via PEP-carboxylase in total carbon fixation as habitats become drier and warmer. Certain species are found in cool moist habitats and exhibit C3-like δ13C values. Other species occur in warm dry habitats and exhibit δ13C values which indicate strong Crassulacean Acid Metabolism. A third group of species shows intermediate δ13C values which are more C3-like in cool moist habitats and which indicate increased dark fixation in warmer and drier situations. Included in this group is Aeonium holochrysum, which of the Sempervivoideae of Teneriffe is thought to be most closely related to the common ancestor (Lems 1960). Comparison of CO2 gas exchange of several species under identical environmental conditions reveals differences among species in the ability to regulate CO2 fixation in the light and in the dark which may have arisen in the process of adaptive radiation.
AU  - Tenhunen, J.D.*
AU  - Tenhunen, L.C.*
AU  - Ziegler, H.*
AU  - Stichler, W.
AU  - Lange, O.L.*
C1  - 41075
C2  - 38868
SP  - 217-224
TI  - Variation in carbon isotope ratios of Sempervivoideae species from different habitats of Teneriffe in the spring.
JO  - Oecologia
VL  - 55
IS  - 2
PY  - 1982
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Plants collected from different habitats in the deserts of India, Saudi Arabia, Egypt, and Iraq were screened for their photosynthetic CO2-fixation pathways using δ13C and δD values. The analyses comprised 128 species belonging to 108 genera and 46 families. Neither the C4 nor the CAM pathway was prevalent in the plant families analyzed except in Poaceae, where C4 metabolism absolutely dominated. Of 93 dicotyledonous plants, only 10 exhibited a C4 pathway and only 2 were CAM plants. The study shows that some species reported by other workers as C4 plants are clearly C3 ones.
AU  - Ziegler, H.
AU  - Batanouny, K.H.
AU  - Sankhlá, N.
AU  - Vyas, O.P.
AU  - Stichler, W.
C1  - 41047
C2  - 38133
SP  - 93-99
TI  - The photosynthetic pathway types of some desert plants from India, Saudi Arabia, Egypt, and Iraq.
JO  - Oecologia
VL  - 48
IS  - 1
PY  - 1981
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Measurements of carbon isotope ratios of central Mexican Crassulaceae collected over a broad habitat range show consistent patterns of CAM activity with no indications of substantial flexible photosynthetic pathways between C3 and CAM. The three genera studied - Echeveria, Pachyphytum, and Graptopetalum - are all closely related to Dudleya in which considerable flexible metabolic response has been demonstrated. Comparative measurements of carbon isotope ratios for field collected and greenhouse reared samples of the same taxa showed a uniform occurrence of slightly more negative δ 13C values, but no indication of substantial flexible metabolic response.
AU  - Rundel, P.W.*
AU  - Rundel, J.A.*
AU  - Ziegler, H.*
AU  - Stichler, W.
C1  - 40865
C2  - 38462
SP  - 45-50
TI  - Carbon isotope ratios of central Mexican Crassulaceae in natural and greenhouse environments.
JO  - Oecologia
VL  - 38
IS  - 1
PY  - 1979
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Measurements of carbon isotope ratios of nine taxa of arid zone mosses from North America and 24 taxa of European bryophytes show consistent values indicative of C3 metabolism. Other morphological, physiological and biochemical characteristics provide the mechanism of adaptation to environmental stresses of heat and extended desiccation in these plants. Analyses of D content indicate that values become less negative with increasing aridity of the habitat.
AU  - Rundel, P.W.*
AU  - Stichler, W.
AU  - Zander, R.H.*
AU  - Ziegler, H.*
C1  - 41462
C2  - 35765
SP  - 91-94
TI  - Carbon and hydrogen isotope ratios of bryophytes from arid and humid regions.
JO  - Oecologia
VL  - 44
IS  - 1
PY  - 1979
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Ribulosediphosphate carboxylase can be extracted from Pseudevernia furfuracea, either by Triton X-100 or by pretreatment with liquid nitrogen. With respect to HCO3 - the Kmis 33 mM. The enzyme is competitively inhibited by sulfite, as is the case with spinach chloroplasts. The Kivalue (15.5-18.5 mM sulfite) indicates that in lichens the enzyme is not more sensitive than that in spinach. Thus the extreme sensitivity of lichens to SO2 is not based on low tolerance at the enzymatic level, but is due to a low degree of avoidance.
AU  - Ziegler, I.
C1  - 41682
C2  - 35686
SP  - 63-66
TI  - Sulfite action on ribulosediphosphate carboxylase in the Lichen Pseudevernia furfuracea.
JO  - Oecologia
VL  - 29
IS  - 1
PY  - 1977
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - 1. The 4 alpine species of Sempervivum (S. arachnoideum L., S. montanum L., S. soboliferum Sims, S. wulfenii Hoppe) analyzed in this study showed acidification during the dark period in their natural habitat. The δ13C value of these species varied according to the water supply at their natural habitat, being less negative at dry sites. These data are consistent with a larger contribution of dark CO2 fixation via Phosphoenolpyruvate-Carboxylase in relation to light CO2 fixation via Ribulose-1, 5-diphosphate Carboxylase. These alpine Sempervivum spp. behave, therefore, like typical CAM-plants. 2. In contrast, the 3 alpine species of Sedum analyzed in this respect (S. acre. L., S. alpestre Vill., S. rosea (L.) Scop.) showed no pronounced dark acidification. The δ13C value of the 8 alpine Sedum species examined in this study (the 3 mentioned above and S. album L., S. atratum L., S. dasyphyllum L., S. reflexum L., S. sexangulare L.) was much more negative than in the Sempervivum spp., indicating that the dark CO2 fixation does not play a great role in the carbon metabolism of the alpine Sedum spp. in the natural habitats. Water supply in the natural habitat has no clear-cut influence on the δ13C value. 3. All alpine species of Saxifraga analysed (S. seloides L., S. oppositifolia L., S. bryoides L., S. aizoides L., S. squarrosa Sieber, S. paniculata Mill., S. caesia L.) show δ13C values typical of C3 plants and they were not influended by the water conditions in the natural sites. Saxifraga paniculata showed no dark acidification in its natural habitat and we suspect that alpine Saxifrages are not CAM plants. 4. Based on δ13C values the alpine plants Pinguicula alpina L., Thesium alpinum L., and Linaria alpina (L.) Mill. are typical C3 plants.
AU  - Osmond, B.*
AU  - Ziegler, H.*
AU  - Stichler, W.
AU  - Trimborn, P.
C1  - 41510
C2  - 35424
SP  - 209-217
TI  - Carbon isotope discrimination in alpine succulent plants supposed to be capable of Crassulacean Acid Metabolism (CAM).
JO  - Oecologia
VL  - 18
IS  - 3
PY  - 1975
SN  - 0029-8549
ER  - 

TY  - JOUR
AB  - Plants of the Indian desert belonging to 29 families, 85 genera and 105 species of angiosperms were screened for the possible occurrence of the C4-pathway of photosynthetic CO2-fixation. The criteria used for screening were leaf anatomy and/or δ13C values. The results indicated the occurrence of the C4-pathway in members of 3 new families (Acanthaceae, Cleomaceae, Scrophulariaceae), 10 new genera (Aerva, Anticharis, Blepharis, Elyonurus, Glossocardia1, Gynandropsis, Melanocenchris, Sehima, Sesuvium, Zalaeya) and 34 new species of the angiosperms. All the grasses investigated were found to possess the C4-pathway. Cuscuta hyalina, a phloem-parasite, growing on C4 hosts (Tribulus, Zalaeya) also revealed δ13C value very close to that found in the host plants.
AU  - Sankhlá, N.*
AU  - Ziegler, H.*
AU  - Vyas, O.P.*
AU  - Stichler, W.
AU  - Trimborn, P.
C1  - 40999
C2  - 38799
SP  - 123-129
TI  - Eco-physiological studies on Indian arid zone plants - V. A. Screening of some species for the C4-pathway of photosynthetic CO2-fixation.
JO  - Oecologia
VL  - 21
IS  - 2
PY  - 1975
SN  - 0029-8549
ER  -