TY - JOUR A1 - Zimmermann, Dirk A1 - Reuss, Randolph A1 - Westhoff, Markus A1 - Geßner, Petra A1 - Bauer, Matthias Wolf A1 - Bamberg, Ernst A1 - Bentrup, Friedrich-Wilhelm A1 - Zimmermann, Ulrich T1 - A novel, non-invasive, online-monitoring, versatile and easy plant-based probe for measuring leaf water status T2 - The journal of experimental botany N2 - A high-precision pressure probe is described which allows non-invasive online-monitoring of the water relations of intact leaves. Real-time recording of the leaf water status occurred by data transfer to an Internet server. The leaf patch clamp pressure probe measures the attenuated pressure, Pp, of a leaf patch in response to a constant clamp pressure, Pclamp. Pp is sensed by a miniaturized silicone pressure sensor integrated into the device. The magnitude of Pp is dictated by the transfer function of the leaf, Tf, which is a function of leaf patch volume and ultimately of cell turgor pressure, Pc, as shown theoretically. The power function Tf=f(Pc) theoretically derived was experimentally confirmed by concomitant Pp and Pc measurements on intact leaflets of the liana Tetrastigma voinierianum under greenhouse conditions. Simultaneous Pp recordings on leaflets up to 10 m height above ground demonstrated that changes in Tf induced by Pc changes due to changes of microclimate and/or of the irrigation regime were sensitively reflected in corresponding changes of Pp. Analysis of the data show that transpirational water loss during the morning hours was associated with a transient rise in turgor pressure gradients within the leaflets. Subsequent recovery of turgescence during the afternoon was much faster than the preceding transpiration-induced water loss if the plants were well irrigated. Our data show the enormous potential of the leaf patch clamp pressure probe for leaf water studies including unravelling of the hydraulic communication between neighbouring leaves and over long distances within tall plants (trees). KW - irrigation KW - leaf patch clamp pressure KW - liana KW - Tetrastigma voinierianum KW - transfer function KW - turgor pressure KW - turgor pressure probe Y1 - 2008 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/5853 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30-57965 SN - 1460-2431 SN - 0022-0957 N1 - © 2008 The Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper is available online free of all access charges (see http://jxb.oxfordjournals.org/open_access.html for further details) VL - 59 IS - 11 SP - 3157 EP - 3167 PB - Oxford Univ. Press CY - Oxford ER -