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Xylem-fed maple sap accelerates balsam fir needle abscission and but can delay water loss in spring and autumn

100%

MacDonald M. T., Lada R. R., West R. R., Nelson K. L.

Dendrobiology

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2016

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tom 76

Postharvest balsam fir trees are known to suffer a number of problems that may be linked to abscission rates, such as dehydration or wounding. By definition, postharvest balsam fir trees are also detached from roots and will no longer be supplied certain root derived factors normally translocated via the xylem. Resupplying those root derived factors may delay abscission. The objective of this experiment was to take sap from a root intact species (i.e. Acer saccharum L) and add it to the water supply of balsam fir branches. Further, the effect of reverse osmosis and autoclaving the sap supply will be explored. The experiment was conducted once in spring and again in autumn to examine seasonal changes in needle abscission. The only hormones found in the maple sap were ABA and its metabolites, with PA (163.0 ng g–1) being the primary metabolite present. Needle retention was higher in branches harvested in autumn, as long as they were provided a sap that did not undergo RO. If the sap had undergone RO, then needle retention was slightly decreased in autumn. Needle retention generally decreased as the concentration of maple sap in the water supply increased and this trend was accelerated if the sap had undergone RO. Autoclaving the sap successfully delayed the length of time for water consumption to decrease, but this unexpectedly did not translate into improved needle retention.

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The age-related changes of leaf structure and biochemistry in juvenile and mature subalpine fir trees (Abies faxoniana Rehder and E.H. Wilson.) along an altitudinal gradient

100%

Peng G., Wu C., Xu X., Yang D.

Polish Journal of Ecology

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2012

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tom 60

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nr 2

In woody perennials, leaf structure and biochemistry vary with tree age under changing environments. However, the related eco-physiological mechanisms have not been elucidated yet. In this study, we investigated agerelated responses of juvenile and mature subalpine fir trees (Abies faxoniana Rehder & E.H. Wilson.) growing at altitudes between 2,500 and 3,500 m in the Wanglang Natural Reserve in southwest China, to study the adaptive strategies of different age trees to suit changing environments. We found that there were distinct age- and altituderelated changes in the structural and biochemical characteristics of leaves. At all altitudes, mature trees exhibited higher area- and mass-based leaf nitrogen content (Narea, Nmass), leaf mass per area (LMA) and stable isotope carbon composition (δ13C), and a lower chlorophyll (Chl) content than those juvenile trees, except for Nmass at 3,000 m as well as LMA at 2,750 m, where the values of Nmass and LMA in mature trees were slightly lower than those in juvenile trees. Furthermore, leaf characteristics showed significant differences in the change rates with altitude between different age groups. Our results indicated that assimilative organs in mature trees do not suffering from nutrient deficiency and that juvenile and mature trees possess different adaptive growth strategies under changing environments, as indicated by higher leaf N content in mature trees and the opposite patterns of LMA and Chl content between two age groups. We also concluded that juvenile could be more sensitive to global warming due to a greater altitudinal influence on the leaf traits in juvenile trees than those in mature trees.

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Study of metal content and peroxidase activity in pine, spruce and fir trees exposed to different concentrations of toxic metals

100%

Jeremic A., Radotic K.

Biological Bulletin of Poznań. Supplement

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1997

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tom 34

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Tree-ring estimation of the effect of industrial pollution on pine [Pinus sylvestris] and fir [Abies alba] in the Ojcow National Park [Southern Poland]

100%

Krapiec M., Szychowska-Krapiec E.

Nature Conservation

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2001

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tom 58

Ograniczanie wyników

1 Biological Bulletin of Poznań. Supplement

1 Dendrobiology

1 Nature Conservation

1 Polish Journal of Ecology

1 Jeremic A.

1 Krapiec M.

1 Lada R. R.

1 MacDonald M. T.

1 Nelson K. L.

1 Peng G.

1 Radotic K.

1 Szychowska-Krapiec E.

1 West R. R.

1 Wu C.

1 Xu X.

1 Yang D.

1 2016

1 2012

1 2001

1 1997

Xylem-fed maple sap accelerates balsam fir needle abscission and but can delay water loss in spring and autumn

The age-related changes of leaf structure and biochemistry in juvenile and mature subalpine fir trees (Abies faxoniana Rehder and E.H. Wilson.) along an altitudinal gradient

Study of metal content and peroxidase activity in pine, spruce and fir trees exposed to different concentrations of toxic metals

Tree-ring estimation of the effect of industrial pollution on pine [Pinus sylvestris] and fir [Abies alba] in the Ojcow National Park [Southern Poland]