Linked Life Data

17171284

Source:http://linkedlifedata.com/resource/pubmed/id/17171284

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-3
pubmed:dateCreated
2007-4-27
pubmed:abstractText
A serious forest decline of Betula ermanii Cham. has been observed at Mt. Mae-Shirane, Oku-Nikko, Japan, where high ozone (O3) concentration and severe water deficiency have been measured. In order to consider the possibility whether O3 and/or water stresses could have been the causes of the forest decline of B. ermanii, plant growth experiments were conducted in environment-controlled growth cabinets. Two-year-old seedlings of B. ermanii were exposed to either charcoal-filtered air (O3 concentration <5 ppb) or 50 ppb O3 (daily average, ranging between 20-100 ppb) for 123 days at 20.0/12.5 +/- 1.0 degrees C (day/night) and 70/80 +/- 7% relative humidity (day/night). Simultaneously, seedlings were treated with three watering regime: 1.0 < pF < 1.8 (no water stress), 1.8 < pF < 2.5 (mild water stress) or 2.5 < pF < 3.0 (severe water stress). O3 exposure significantly reduced the dry weights of leaf, root and the whole plant, while water stress significantly reduced the dry weights of each organ and the whole plant. Significant reductions of net photosynthesis, transpiration and stomatal conductance were also observed under O3 and/or water deficiency treatments, while contents of RuBP carboxylase/oxygenase (Rubisco), chlorophyll( a+b ) and some essential nutrient elements (N, P, K, Mg and Ca) were not markedly changed. It was suggested that the decrease in net photosynthetic rate induced mainly by stomatal closure was the major cause of the growth reduction under O3 and/or water stresses. No significant interactions between O3 and water stresses were observed in terms of the depression of dry matter production, which suggested that simultaneous stress treatments of O3 exposure and water deficiency could affect the tree growth of B. ermanii additively.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0167-6369
pubmed:author
pubmed:issnType
Print
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109-19
pubmed:dateRevised
2009-5-11
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Ozone and/or water stresses could have influenced the Betula ermanii cham. forest decline observed at Oku-Nikko, Japan.
pubmed:affiliation
National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506, Ibaraki, Japan. hshimizu@nies.go.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't