UV-B effects on physiological parameters of three species of Rumex with natural distribution at different altitudes

Hübner, Carin; Ziegler, H.

doi:10.1016/s0176-1617(98)80148-x

Cited by 8 publications

(4 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Experiments were run at 20°C and at a relative humidity of 55%. The compiled data were handled by the program DIAGAS (Walz), resulting in conductances for water, oxygen and carbon dioxide (Hu¨bner and Ziegler 1998). As the calculations incorporate only molar concentrations we have recalculated the original data, introducing the gas constant.…”

Section: Transpiration Via Stomatamentioning

confidence: 99%

Water and oxygen permeance of phellems isolated from trees: the role of waxes and lenticels

Groh

Hübner

Lendzian

2002

Planta

Self Cite

View full text Add to dashboard Cite

The outermost phellems of Abies alba Mill., Acer pseudoplatanus L., Aesculus hippocastanum L., Betula potaninii L.C. Hue and Sambucus nigra L. have been isolated enzymatically, resulting in membranes with five to seven heavily suberized cork cell layers. Water and oxygen permeances were determined for the phellem areas without lenticels. A special diaphragm made it possible to quantify permeances of single lenticels for the first time. The water permeance of phellems was in the range of 3x10(-5) to 9x10(-5) ms(-1) and can be predicted from the density of the phellem membranes with 93% accuracy. Embedded waxes amounted to 3% ( Aesculus) and up to 35% ( Betula) of the dry weight but affected water permeance only to a small degree. The sorption isotherms describing the water content of the phellems in relation to relative humidities followed a hyperbolic shape and indicated varying water contents among plant species. It is argued that water transfer across the phellems occurs via the middle lamellae. Phellem membranes were impermeable to oxygen. Removal of the waxes hardly changed this situation. Single lenticels from Betula and Sambucus were significantly more permeable to water and oxygen than phellem areas without lenticels. The water permeance was elevated by factors of 39 for Betula and 12 for Sambucus, the oxygen permeance by factors of 1,202 for Betula and 53 for Sambucus. Extraction of lenticels did not affect permeance. A quantitative comparison of the gas-exchange capacity of lenticels and stomata demonstrated the superiority of stomata. However, differences may be not more than one order of magnitude.

show abstract

Section: Transpiration Via Stomatamentioning

confidence: 99%

Water and oxygen permeance of phellems isolated from trees: the role of waxes and lenticels

Groh

Hübner

Lendzian

2002

Planta

Self Cite

View full text Add to dashboard Cite

show abstract

“…The interaction between UV-B radiation and moderate drought is still not well-understood. Furthermore, evidence from plant research indicates that there can be altitudinal variation in response to UV-B (Hubner and Ziegler, 1998;Rau and Hofmann, 1996). However, few studies have examined the same species from both high and low altitude sites (Yang et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Intraspecific variation in drought response of Populus cathayana grown under ambient and enhanced UV-B radiation

Duan²,

Zhang³

et al. 2009

Ann. For. Sci.

View full text Add to dashboard Cite

Keywords:carbon nitrogen ratio / photosynthetic nitrogen use efficiency / Populus cathayana / ultraviolet-b radiation / water use efficiency Abstract • The effects of drought, enhanced UV-B radiation and their combination on plant growth and physiological traits were investigated in a greenhouse experiment in two populations of Populus cathayana Rehder originating from high and low altitude in south-west China.• In both populations, drought significantly decreased biomass accumulation and gas exchange parameters, including net CO 2 assimilation rate (A), stomatal conductance (g s ), transpiration rate (E) and photosynthetic nitrogen use efficiency (PNUE). However, instantaneous water use efficiency (WUE i ), transpiration efficiency (WUE T ), carbon isotope composition (δ 13 C) and nitrogen (N) content, as well as the accumulation of soluble protein, UV-absorbing compounds and abscisic acid (ABA) significantly increased in response to drought. On the other hand, cuttings from both populations, when kept under enhanced UV-B radiation, showed very similar changes, as under drought, in all above-mentioned parameters.• Compared with the low altitude population, the high altitude population was more tolerant to drought and enhanced UV-B, as indicated by the higher level of biomass accumulation, gas exchange, water-use efficiency, ABA concentration and UV-absorbing compounds.• After one growing season of exposure to different UV-B levels and watering regimes, the decrease in biomass accumulation and gas exchange, induced by drought, was more pronounced under the combination of UV-B and drought. Significant interactions between drought and UV-B were observed in WUE i , WUE T , δ 13 C, soluble protein, UV-absorbing compounds, ABA and in the leaf and stem N, as well as in the leaf and stem C:N ratio.• Our results showed that UV-B acts as an important signal allowing P. cathayana seedlings to respond to drought and that the combination of drought and UV-B may cause synergistically detrimental effects on plant growth. Mots-clés :rapport carbone / azote / efficience photosynthétique d'utilisation de l'azote / Populus cathayana / rayonnement UV-B / efficience d'utilisation de l'eau Résumé -Variations intra-spécifiques de la réponse à la sécheresse de Populus cathayana sous atmosphère ambiante ou sous un rayonnement UV-B accru.• Les effets d'une sécheresse, d'une augmentation du rayonnement UV-B et de leur combinaison ont été étudiés sur la croissance et les caractéristiques physiologiques de plants de deux populations de Populus cathayana Rehder originaires de haute et basse altitude dans le sud-ouest de la Chine.• Dans les deux populations, la sécheresse a réduit de manière significative l'accumulation de biomasse et les échanges gazeux foliaires, y compris l'assimilation nette (A) de CO 2 , la conductance stomatique (g s ), la transpiration (E) et l'efficience photosynthétique d'utilisation de l'azote (PNUE). Toutefois, l'efficience instantanée d'utilisation de l'eau (WUE i ), l'efficience de transpiration (WUE T ), la com...

show abstract

“…For example, UV-B may increase with increasing altitude (Blumthaler et al 1997 along altitudinal gradients, we might expect differences in sensitivity between high-and low-elevation populations. Evidence from plant research indicates that there can be altitudinal variation in response to UV-B (Caldwell 1968, Rau and Hofmann 1996, Hubner and Ziegler 1998.…”

Section: Introductionmentioning

confidence: 99%

Population Differences in Sensitivity to Uv-B Radiation for Larval Long-Toed Salamanders

Belden

Blaustein

2002

Ecology

View full text Add to dashboard Cite

Ultraviolet‐B radiation (UV‐B; 280–320 nm) penetrates some aquatic habitats to biologically significant depths and can alter life histories of aquatic organisms, including algae, zooplankton, fish, and amphibians. Although major species differences have been documented for UV‐B sensitivity, few studies have examined differences between populations of the same species. Previous work has suggested the hypothesis that larval long‐toed salamanders (Ambystoma macrodactylum) from valley populations (∼100 m elevation) were more sensitive to UV‐B exposure than larvae from mountain populations (above 500 m elevation). To test this hypothesis in the absence of possible other confounding environmental effects, we brought early‐stage embryos into the laboratory from three valley populations and five mountain populations from Oregon and Washington and raised them under identical conditions without UV‐B for two months after hatching. Larvae from each population were then placed under UV‐B lighting, and we recorded their growth and survivorship for three weeks. Larvae from all populations had higher mortality when exposed to UV‐B than when shielded from UV‐B. However, individuals from low‐elevation populations exposed to UV‐B had significantly lower survivorship than did those from high‐elevation populations, suggesting an elevational difference in UV‐B sensitivity. In all populations, individuals exposed to UV‐B were smaller than shielded individuals after one week. If UV‐B is a factor in determining the long‐term persistence of some amphibian species, an understanding of within‐species variation is critical.

show abstract

UV-B effects on physiological parameters of three species of Rumex with natural distribution at different altitudes

Cited by 8 publications

References 21 publications

Water and oxygen permeance of phellems isolated from trees: the role of waxes and lenticels

Water and oxygen permeance of phellems isolated from trees: the role of waxes and lenticels

Intraspecific variation in drought response of Populus cathayana grown under ambient and enhanced UV-B radiation

Population Differences in Sensitivity to Uv-B Radiation for Larval Long-Toed Salamanders

Contact Info

Product

Resources

About