TY - JOUR
T1 - Plant hydraulic conductance measured by the high pressure flow meter in crop plants
AU - Tsuda, Makoto
AU - Tyree, Melvin T.
N1 - Funding Information:
A part of this study was supported by the JSPS Invitation Fellowship program for research in Japan to Melvin T Tyree (S-97129).
PY - 2000/4
Y1 - 2000/4
N2 - A new high pressure flow meter (HPFM) method for measuring plant hydraulic conductances (K) was investigated to examine whether its results are comparable to those from a conventional evaporative flux (EF) method in crops. Hydraulic conductance (K) was measured by the two methods under quasi-steady-state conditions in six crops grown in pots: soybean (Glycine max L. Merr. cv. Tsurunoko daizu), sunflower (Helianthus annuus L. cv. Russian mammoth), kidney bean (Phaseolus vulgaris L. cv. Tsurunashi morocco), tomato (Lycopersicon esculentum Mill. cv. Sekai-ichi), green pepper (Capsicum annuum L. cv. shishitou), and eggplant (Solanum melongena L. cv. Seiguro chunaga nasu). There was a 1:1 agreement between K values measured by the two methods for K values of whole plant, root and stem, and leaf under quasi-steady-state conditions. Leaf water potential (Ψ(leaf)) and evaporative flux density (E) in sunflower was curvilinear, indicating whole plant K estimated by the EF method increased with increase of E. Predicted (Ψ(leaf)) (=E divided by whole plant K measured by the HPFM method) agreed with measured Ψ(leaf). Diurnal changes were also found in K measured by the HPFM confirming that K changed in response to temperature and E. The HPFM revealed that variable conductance was located in all organs: roots, stems, petioles, and leaves. These observations indicated that the HPFM is valid for crops as well as for trees (as previously established by Tsuda and Tyree) and has advantages over the EF method because of the speed and ease of the HPFM method.
AB - A new high pressure flow meter (HPFM) method for measuring plant hydraulic conductances (K) was investigated to examine whether its results are comparable to those from a conventional evaporative flux (EF) method in crops. Hydraulic conductance (K) was measured by the two methods under quasi-steady-state conditions in six crops grown in pots: soybean (Glycine max L. Merr. cv. Tsurunoko daizu), sunflower (Helianthus annuus L. cv. Russian mammoth), kidney bean (Phaseolus vulgaris L. cv. Tsurunashi morocco), tomato (Lycopersicon esculentum Mill. cv. Sekai-ichi), green pepper (Capsicum annuum L. cv. shishitou), and eggplant (Solanum melongena L. cv. Seiguro chunaga nasu). There was a 1:1 agreement between K values measured by the two methods for K values of whole plant, root and stem, and leaf under quasi-steady-state conditions. Leaf water potential (Ψ(leaf)) and evaporative flux density (E) in sunflower was curvilinear, indicating whole plant K estimated by the EF method increased with increase of E. Predicted (Ψ(leaf)) (=E divided by whole plant K measured by the HPFM method) agreed with measured Ψ(leaf). Diurnal changes were also found in K measured by the HPFM confirming that K changed in response to temperature and E. The HPFM revealed that variable conductance was located in all organs: roots, stems, petioles, and leaves. These observations indicated that the HPFM is valid for crops as well as for trees (as previously established by Tsuda and Tyree) and has advantages over the EF method because of the speed and ease of the HPFM method.
KW - Evaporative flux method
KW - High pressure flow meter method
KW - Hydraulic conductance
KW - Root
KW - Shoot
KW - Variable conductance
KW - Water potential
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U2 - 10.1093/jxb/51.345.823
DO - 10.1093/jxb/51.345.823
M3 - Article
C2 - 10938875
AN - SCOPUS:0034098763
VL - 51
SP - 823
EP - 828
JO - Journal of Experimental Botany
JF - Journal of Experimental Botany
SN - 0022-0957
IS - 345
ER -