Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Potassium
Type of Medium
Language
Year
  • 1
    Language: English
    In: Plant and Soil, 2002, Vol.243(2), pp.209-217
    Description: Nutrient concentrations in the rhizosphere soil can be higher, lower or remain unchanged compared to the bulk soil, but relatively little is known about such changes for basic cations in the rhizosphere of tree roots. A modified root container technique of studying rhizosphere processes was employed. Plexiglas cylinders were horizontally split by a membrane with 30 μM mesh size into an upper compartment for root growth and a root-free lower compartment, each with an inner diameter of 5 cm and a height of 10 cm. One 2-year-old Norway spruce ( Picea abies) seedling was transplanted from a nursery into each cylinder. Plants were not specifically inoculated, but roots were colonised by a mix of ectomycorrhizal fungi originating from the nursery. The nutrient poor mineral soil used in the experiment was taken from a forest site in Bayerischer Wald, southern Germany. The soil was either supplied with a mix of Ca, Mg and K, or not supplied with these cations. Plants were harvested 30 weeks after transplanting. The nylon membrane between the root compartments restricted root growth to the upper compartment, so that by the end of the experiment a root mat was formed at the top side of the membrane. In the lower compartment, soil nearest to the root mat was regarded as rhizosphere soil while soil in a distance from the root mat was regarded as bulk soil. In the upper compartment, rhizosphere soil was obtained at the end of the experiment by gently shaking the roots. The soils were analysed for Ca, Mg and K contents following two different soil extraction methods. In the fertilised treatment, H 2 O-extractable Ca and Mg were accumulated in the rhizosphere. In contrast, K (NH 4 Cl-extraction) was depleted in the rhizosphere. In the bottom tube, the depletion of K (NH 4 Cl-extraction) was restricted to 1 cm distance from the root mat. In unfertilised soil, Ca, Mg and K concentrations did not differ clearly between rhizosphere and bulk soils. The results indicated that the occurrence of cation gradients in the rhizosphere depended on the level of soil nutrient supply. Distinct rhizosphere effects were measured by conventional soil extraction methods only when the soil was freshly fertilised with mineral elements prior to the experiment. In this case, K depletion in the rhizosphere reflected higher K uptake by the fertilised Norway spruce plants. For low-nutrient soils, novel techniques are required to follow subtle changes in the rhizosphere.
    Keywords: calcium ; cation supply ; extractable cations ; magnesium ; Norway spruce ; potassium ; rhizosphere chemistry
    ISSN: 0032-079X
    E-ISSN: 1573-5036
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Journal of Plant Nutrition, 05 March 2010, Vol.33(5), pp.736-751
    Description: A semi-hydroponic culture was used to compare growth and cation nutrition of mycorrhizal (Paxillus involutus) and non-mycorrhizal Scots pine seedlings. When roots and hyphae grew together, concentrations and contents of macronutrients in needles and roots were not significantly different between...
    Keywords: Ectomycorrhiza ; Plant Growth ; Nutrients ; Pinus Sylvestris ; Botany
    ISSN: 0190-4167
    E-ISSN: 1532-4087
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    In: Tree Physiology, 2009, Vol. 29(2), pp.199-206
    Description: Nutrient sources in soils are often heterogeneously distributed. Although many studies have examined the root responses to local N and P enrichments in the soil, less research was conducted on root responses to Mg patches. New roots of pre-grown Mg-insufficient and Mg-sufficient plants of Norway spruce ( Picea abies [L.] Karst.) and Scots pine ( Pinus sylvestris L.) seedlings were allowed to grow into four other pots of equal size, which were placed under the tree-bearing pot. Soils in the lower pots were either unfertilised, or supplied with Mg, or NPK or a mixture of NPKMg sources. Plants were harvested after 9 months of growth. Compared to the corresponding controls (Mg versus unfertilised and NPKMg versus NPK), Mg additions did not have a significant effect on either root dry matter, total root length (TRL) or specific root length (SRL), irrespective of tree species and plant Mg nutritional status. In contrast, NPK and NPKMg additions significantly increased the root dry matter and TRL in the nutrient-rich soil patch, and decreased SRL in Norway spruce. However, the observed root morphological changes did not occur in Scots pine. Root Mg concentrations were increased in Mg-rich soil patches, but those accumulations varied with tree species. Mg accumulation in a marked patch was measured only in newly grown roots of Mg-sufficient Norway spruce, whereas a more homogenous distribution of Mg concentration was observed for all newly grown roots in Mg-insufficient trees in the four soil treatments. In Scots pine, Mg accumulations occurred in both Mg-insufficient and Mg-sufficient plants. These results suggest that Mg patches in the soil may not lead to a local increase in root growth, but to Mg uptake and root Mg accumulation. Tree roots react differently to Mg patches in comparison to their response to N or P patches in the soil.
    Keywords: Coniferous Tree ; Nutrient Concentrations ; Nutrient - Enriched Soil ; Nutrient Patches ; Plant Nutritional Status ; Root Growth ; Root Plasticity
    ISSN: 0829-318X
    E-ISSN: 1758-4469
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Mycorrhiza, 2007, Vol.17(5), pp.469-474
    Description: Two challenges frequently encountered in the production of ornamental plants in organic horticulture are: (1) the rate of mineralization of phosphorus (P) and nitrogen (N) from organic fertilizers can be too slow to meet the high nutrient demand of young plants, and (2) the exclusive use of peat as a substrate for pot-based plant culture is discouraged in organic production systems. In this situation, the use of beneficial soil microorganisms in combination with high quality compost substrates can contribute to adequate plant growth and flower development. In this study, we examined possible alternatives to highly soluble fertilizers and pure peat substrates using pelargonium ( Pelargonium peltatum L’Her.) as a test plant. Plants were grown on a peat-based substrate with two rates of compost addition and with and without arbuscular mycorrhizal (AM) fungi. Inoculation with three different commercial AM inocula resulted in colonization rates of up to 36% of the total root length, whereas non-inoculated plants remained free of root colonization. Increasing the rate of compost addition increased shoot dry weight and shoot nutrient concentrations, but the supply of compost did not always completely meet plant nutrient demand. Mycorrhizal colonization increased the number of buds and flowers, as well as shoot P and potassium (K) concentrations, but did not significantly affect shoot dry matter or shoot N concentration. We conclude that addition of compost in combination with mycorrhizal inoculation can improve nutrient status and flower development of plants grown on peat-based substrates.
    Keywords: Arbuscular mycorrhiza ; Compost ; Organic horticulture ; Pelargonium
    ISSN: 0940-6360
    E-ISSN: 1432-1890
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    In: HortScience, 06/2006, Vol.41(3), pp.628-632
    Description: Organic horticultural production systems often are characterized by the use of beneficial soil microorganisms because the application of soluble inorganic P or N fertilizers is not endorsed. Due to the limited supply of soluble nutrients in organic production systems, nutrient deficiency may limit plant growth and yield. The sole use of peat for pot-based cultures is also discouraged in organic production systems. Therefore, we have studied viable alternatives for highly soluble fertilizers and pure peat substrates using leek [Allium ampeloprasum L. var. Porrum] as a test plant. Plants were grown on peat-based substrates with different rates of compost additions, and with and without inoculation with arbuscular mycorrhizal (AM) fungi. Inoculation with a commercial AM fungus inoculum resulted in colonization rates of up to 70% of total root length, whereas not inoculated plants remained free of root colonization. Mycorrhizal fungus colonization increased shoot Zn and K concentrations, but did not significantly affect shoot dry matter or shoot N and P concentrations. In contrast, compost addition increased plant growth, and also increased P and K concentrations in plants. We conclude that plants with high rates of mycorrhizal colonization can be obtained on peat-based substrates, but that under these conditions plants may not consistently benefit in growth from the mycorrhizal symbiosis. In contrast, additions of compost are a possible means to improve the substrate quality in organic horticultural production. ; Includes references ; p. 628-632.
    Keywords: Zinc ; Mycorrhizal Fungi ; Allium Ampeloprasum ; Phosphorus ; Microbial Colonization ; Organic Production ; Allium Porrum ; Growing Media ; Inoculation Methods ; Nitrogen ; Vesicular Arbuscular Mycorrhizae ; Peat ; Dry Matter Accumulation ; Nutrient Uptake ; Plant Growth ; Potassium ; Composts ; Plant Nutrition ; Leeks;
    ISSN: 0018-5345
    E-ISSN: 2327-9834
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    In: Canadian Journal of Botany (Revue canadienne de botanique), 1992, Vol.70(11), pp.2130-2137
    Description: To test the ability of vesiculararbuscular mycorrhizal (VAM) hyphae to take up water, phosphorus, nitrogen, and potassium, mycorrhizal and nonmycorrhizal couchgrass ( Agropyron repens ) or white clover ( Trifolium repens ) plants were grown in pots with separated compartments for roots and hyphae growth. Soil solution transfer between compartments was blocked by a 2-mm air gap. Total shoot contents of phosphate and nitrogen, but not of potassium, were higher in mycorrhizal plants with access to the hyphal compartment. Hyphal uptake from the outer compartment accounted for 49% of the total phosphate and 35% of the total nitrogen taken up by mycorrhizal plants. This was associated with depletion of extractable phosphate, -nitrogen, and also -nitrogen in the soil of the hyphal compartments. In contrast, no difference in water loss from the hyphal compartments was measured by tensiometers under well-watered and water-stress conditions whether hyphae were present or not. Severance of the external hyphae did not affect water loss from the outer compartments. The results show the ability of VAM hyphae to transport considerable quantities of phosphate and nitrogen to the plant from soil zones several centimetres from the root. However, there was no evidence for a significant direct water transport by VAM hyphae to plants. Key words : Agropyron repens (couchgrass), Glomus mosseae , nitrogen, phosphorus, vesiculararbuscular mycorrhiza, water.
    Description: Afin de mettre en vidence la capacit des hyphes de champignons mycorhiziens vsicules et arbuscules (VAM) absorber l'eau, le phosphore, l'azote et le potassium, les auteurs ont cultiv des plants mycorhiziens et non-mycorhiziens de chiendent ( Agropyron repens ) ou de trfle blanc ( Trifolium repens ) en pots avec des compartiments spars pour la croissance des hyphes et des racines. Le transfert de la solution de sol entre les compartiments est empche par un espace d'air de 2mm. Les teneurs totales en phosphore et en azote, mais non pas en potassium, sont plus leves chez les plantes mycorhiziennes ayant accs au compartiment des hyphes. L'abosrption par les hyphes partir du compartiment extrieur compte pour 49% du phosphore total et 35% de l'azote total absorbs par les plantes mycorhiziennes. Ceci est associ avec un puisement du phosphore extractible et de l'azote sous forme de et de dans le sol du compartiment avec les hyphes. Au contraire, aucune diffrence dans la perte d'eau des compartiments avec les hyphes n'a pu tre mesure par des tensiomtres, sous de conditions d'arrosage normal ou de stress hydrique, que les hyphes soient prsents ou pas. La coupure des hyphes externes n'a pas affect la perte d'eau par le compartiment externe. Ces rsultats dmontrent que les hyphes de champignons VAM ont la capacit de transporter de grandes quantits de phosphate et d'azote la plante partir de rgions du sol situes plusieurs centimtres de distance de la racine. Cependanat, il n'a pas t possible de dmontrer un transfert direct et significatif de l'eau par les hyphes des champignons VAM vers la plante. Mots cls : Agropyron repens (chiendent), Glomus mosseae , azote, phosphore, mycorhizes vsicules et arbuscules, eau. [Traduit par la rdaction]
    Keywords: Water ; Nutrients ; Translocation ; Hyphae ; Vesicular-Arbuscular Mycorrhizas ; Mycorrhiza ; Glomus Mossae ; Glomus Mossae;
    ISSN: 0008-4026
    E-ISSN: 1480-3305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    In: Tree Physiology, 1997, Vol. 17(1), pp.39-45
    Description: The spatial distribution of plant-available mineral nutrients in forest soils is often highly heterogeneous. To test the hypothesis that local nutrient enrichment of soil leads to increased root proliferation in the nutrient-rich soil zone, we studied the effects of nutrient enrichment on the growth and nutrient concentrations of Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco), Scots pine ( Pinus sylvestris L.) and Norway spruce ( Picea abies (L.) Karst.) roots. Three-year-old seedlings were grown for 9 months in split-root containers filled with nutrient-poor forest mineral soil, with one side supplemented with additional mineral nutrients. Root dry weight and root length in Scots pine and Norway spruce were increased in the nutrient-supplemented soil compared with the nonsupplemented side, whereas root growth in Douglas-fir was unaffected by nutrient enrichment. Of the three species examined, Norway spruce exhibited the highest root and shoot growth and the highest nutrient demand. Specific root length (m g −1 ) and the number of root tips per unit root length were not affected by local nutrient addition in any of the species. Despite increased root growth in Norway spruce and Scots pine in nutrient-supplemented soil, their root systems contained similar nutrient concentrations on both sides of the split-root container. Thus, coniferous trees may respond to local nutrient supply by increased root proliferation, but the response varies depending on the species, and may only occur when trees are nutrient deficient. As a response to local nutrient enrichment, increases in root dry matter or root length may be better indicators of pre-existing nutrient deficiencies in conifers than increases in root nutrient concentrations.
    Keywords: Douglas - Fir ; Local Nutrient Supply ; Norway Spruce ; Nutrient Concentrations ; Root Growth ; Root Morphology ; Scots Pine
    ISSN: 0829-318X
    E-ISSN: 1758-4469
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    In: Transplantation, 1991, Vol.52(6), pp.984-988
    Description: University of Wisconsin solution has been used successfully in clinical kidney and liver preservation. The object of this study was to determine if low-potassium UW (LPUW) solution could be applied to pulmonary preservation. Rabbit lungs were stored after hypothermic pulmonary artery (PA) flush with four different solutions (group 1: low-potassium dextran (LPD) solution, group 2: high-potassium UW (HPUW) solution, group 3: LPUW solution, group 4: modified Euro-Collins (E-C) solution). The lungs were preserved at 10°C for 30 hr and evaluated in an ex vivo ventilation/perfusion apparatus using fresh pooled venous rabbit blood. Mean PA flush pressures (MFP) during harvesting were significantly lower in groups 1 and 3 (8.1±1.0 mmHg and 7.3±0.6 mmHg, respectively; mean ± SEM) than in groups 2 and 4 (15.5±1.7 mmHg and 12.3±0.9 mmHg, respectively). Lungs in groups 1 and 3 showed significantly higher PaO2 (103.5±8.0 mmHg and 89.3±7.2 mmHg) than groups 2 and 4 (48.3±7.7 mmHg, 66.7±4.7 mmHg). Groups 1 and 3 showed significantly lower wet/ dry weight (W/D) ratios after reperfusion (6.21±0.15 and 6.39±0.23) than groups 2 and 4 (7.70±0.57 and 7.13±0.21, respectively). There were no significant differences in MFP, PaO2, PaCO2, mean pulmonary artery pressure, or W/D ratio between groups 1 and 3. These results suggest that LPUW solution may be as beneficial as LPD solution for pulmonary arterial flush and lung preservation.
    Keywords: Lung ; Organ Preservation Solutions ; Organ Preservation -- Methods ; Potassium -- Analysis ; Solutions -- Chemistry;
    ISSN: 0041-1337
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages