Premium
X‐ray microtomography observations of xylem embolism in stems of Laurus nobilis are consistent with hydraulic measurements of percentage loss of conductance
Author(s) -
Nardini Andrea,
Savi Tadeja,
Losso Adriano,
Petit Giai,
Pacilè Serena,
Tromba Giuliana,
Mayr Stefan,
Trifilò Patrizia,
Lo Gullo Maria A.,
Salleo Sebastiano
Publication year - 2017
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.14245
Subject(s) - laurus nobilis , xylem , botany , ecophysiology , biology , tracheid , photosynthesis , essential oil
Summary Drought‐induced xylem embolism is a serious threat to plant survival under future climate scenarios. Hence, accurate quantification of species‐specific vulnerability to xylem embolism is a key to predict the impact of climate change on vegetation. Low‐cost hydraulic measurements of embolism rate have been suggested to be prone to artefacts, thus requiring validation by direct visualization of the functional status of xylem conduits using nondestructive imaging techniques, such as X‐ray microtomography (micro CT ). We measured the percentage loss of conductance ( PLC ) of excised stems of Laurus nobilis (laurel) dehydrated to different xylem pressures, and compared results with direct observation of gas‐filled vs water‐filled conduits at a synchrotron‐based micro CT facility using a phase contrast imaging modality. Theoretical PLC calculated on the basis of micro CT observations in stems of laurel dehydrated to different xylem pressures overall were in agreement with hydraulic measurements, revealing that this species suffers a 50% loss of xylem hydraulic conductance at xylem pressures averaging −3.5 MPa. Our data support the validity of estimates of xylem vulnerability to embolism based on classical hydraulic techniques. We discuss possible causes of discrepancies between data gathered in this study and those of recent independent reports on laurel hydraulics.