TY  - JOUR
AU  - Pieruschka, R.
AU  - Schurr, U.
AU  - Jahnke, S.
TI  - Lateral gas diffusion inside leaves
JO  - The journal of experimental botany
VL  - 56
SN  - 0022-0957
CY  - Oxford
PB  - Univ. Press
M1  - PreJuSER-42750
SP  - 857 - 864
PY  - 2005
N1  - Record converted from VDB: 12.11.2012
AB  - Diffusion of CO2 inside leaves is generally regarded to be from the substomatal cavities to the assimilating tissues, i.e. in the vertical direction of the leaf blades. However, lateral gas diffusion within intercellular air spaces may be much more effective than hitherto considered. In a previous work it was demonstrated that, when 'clamp-on' leaf chambers are used, leaf internal 'CO2 leakage' beyond the leaf chamber gaskets may seriously affect gas exchange measurement. This effect has been used in the present paper to quantify gas conductance (g(leaf,l), mmol m(-2) s(-1)) in the lateral directions within leaves and significant differences between homo- and heterobaric leaves were observed. For the homobaric leaves, lateral gas conductance measured over a distance of 6 or 8 mm (the widths of the chamber gaskets) was 2-20% of vertical conductance taken from published data measured over much smaller distances of 108-280 microm (the thickness of the leaves). The specific internal gas diffusion properties of the leaves have been characterized by gas conductivities (g*(leaf), micromol m(-1) s(-1)). Gas conductivities in the lateral directions of heterobaric leaves were found to be small but not zero. In homobaric leaves, they were between 67 and 209 micromol m(-1) s(-1) and thus even larger than those in the vertical direction of the leaf blades (between 15 and 78 micromol m(-1) s(-1)). The potential implications for experimentalists performing gas exchange measurements are discussed.
KW  - Carbon Dioxide: physiology
KW  - Diffusion
KW  - Phaseolus: physiology
KW  - Photosynthesis: physiology
KW  - Plant Leaves: physiology
KW  - Plant Transpiration: physiology
KW  - Soybeans: physiology
KW  - Time Factors
KW  - Tobacco: physiology
KW  - Vicia faba: physiology
KW  - Carbon Dioxide (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:15668225
UR  - <Go to ISI:>//WOS:000227565100009
DO  - DOI:10.1093/jxb/eri072
UR  - https://juser.fz-juelich.de/record/42750
ER  -