ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

Electronic Resource

Influences of soil volume and an elevated CO2 level on growth and CO2 exchange for the Crassulacean acid metabolism plant Opuntia ficus-indica (1994)

Nobel, Park S. ; Cui, Muyi ; Miller, Patsy M. ; [et al.]

Oxford, UK : Blackwell Publishing Ltd

Physiologia plantarum 90 (1994), S. 0

add to mindlist on the mindlist

Details

ISSN: 1399-3054

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Biology

Notes: Effects of the current (38 Pa) and an elevated (74 Pa) CO2 partial pressure on root and shoot areas, biomass accumulation and daily net CO2 exchange were determined for Opuntia ficus-indica (L.) Miller, a highly productive Crassulacean acid metabolism species cultivated worldwide. Plants were grown in environmentally controlled rooms for 18 weeks in pots of three soil volumes (2 600, 6 500 and 26 000 cm3), the smallest of which was intended to restrict root growth. For plants in the medium-sized soil volume, basal cladodes tended to be thicker and areas of main and lateral roots tended to be greater as the CO2 level was doubled. Daughter cladodes tended to be initiated sooner at the current compared with the elevated CO2 level but total areas were similar by 10 weeks. At 10 weeks, daily net CO2 uptake for the three soil volumes averaged 24% higher for plants growing under elevated compared with current CO2 levels, but at 18 weeks only 3% enhancement in uptake occurred. Dry weight gain was enhanced 24% by elevated CO2 during the first 10 weeks but only 8% over 18 weeks. Increasing the soil volume 10-fold led to a greater stimulation of daily net CO2 uptake and biomass production than did doubling the CO2 level. At 18 weeks, root biomass doubled and shoot biomass nearly doubled as the soil volume was increased 10-fold; the effects of soil volume tended to be greater for elevated CO2. The amount of cladode nitrogen per unit dry weight decreased as the CO2 level was raised and increased as soil volume increased, the latter suggesting that the effects of soil volume could be due to nitrogen limitations.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1111/j.1399-3054.1994.tb02208.x

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

A large ephemeral release of nitrogen upon wetting of dry soil and corresponding root responses in the field (1997)

Cui, Muyi ; Caldwell, Martyn M.

Springer

Plant and soil 191 (1997), S. 291-299

add to mindlist on the mindlist

Details

ISSN: 1573-5036

Keywords: Agropyron desertorum ; mycorrhizae ; nutrient release by rain ; root growth ; root nutrient uptake kinetics ; soil moisture

Source: Springer Online Journal Archives 1860-2000

Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Notes: Abstract To assess changes in soil nutrients, root growth and mycrorrhizal infection in response to rain events, a water pulse was applied to a very dry soil. Wetting of a dry soil in the Great Basin of the Western United States led to a striking pulse of available soil nitrate in a field plot, but available phosphate was not affected. This is the first field demonstration of this phenomenon in the Great Basin as far as we are aware. This pulse was only apparent for a few days, probably due to microbial immobilization of the nitrogen. Root ammonium uptake capacity increased within one day of the water pulse, but new root growth was not apparent until 3 days after the water pulse. Thus, to capture this ephemeral release of nitrogen, enhanced uptake capacity of existing roots was probably more important than development of new roots. Mycorrhizal infection was not affected by the water pulse treatments. However, since the water pulse only affected nitrogen availability and mycorrhizae are generally most effective in facilitating acquisition of less mobile nutrients such as phosphate, mycorrhizae likely do not play an important role in taking advantage of this opportunity provided by the pulse of water.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1004290705961

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Prediction and measurement of gap water vapor conductance for roots located concentrically and eccentrically in air gaps (1992)

Nobel, Park S. ; Cui, Muyi

Springer

Plant and soil 145 (1992), S. 157-166

add to mindlist on the mindlist

Details

ISSN: 1573-5036

Keywords: Agave deserti ; hydraulic conductivity ; root shrinkage ; soil ; water relations

Source: Springer Online Journal Archives 1860-2000

Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Notes: Abstract Water movement between a root and the soil depends on the hydraulic conductances of the soil, the root, and the intervening root-soil air gap (Lgap) created as roots shrink during soil drying. To measure Lgap, segments of young cylindrical roots of Agave deserti about 3 mm in diameter were placed concentrically or eccentrically within tubes of moistened filter paper at a known water potential. As the width of the air gap between the filter paper and a concentrically located root was made smaller, measured Lgap increased less than did predicted Lgap based on isothermal conditions. For gaps of the size expected in the soil during water loss from roots (e.g., 10% of the root radius), the underprediction was about 70% and was primarily caused by a lowering of the root surface temperature accompanying water evaporation. As a root segment was eccentrically moved toward the filter paper, the measured Lgap increased. For the most eccentric case of touching the filter paper, the measured Lgap was 2.4-fold greater than for the concentric case, compared with an infinite Lgap predicted if the water potential were constant around the root surface. When a root touched soil with a water potential of -1.0MPa, Lgap estimated using a graphical method increased about 2.3-fold and the overall conductance of the root-soil system increased by 31% compared with the concentric case. For markedly eccentric locations of roots in air gaps, Lgap, which can be the principal conductance initially limiting water loss from roots to a drying soil, can be about 60% of the value predicted for the concentric isothermal case.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00010344

Permalink