Herbaceous angiosperms are not more vulnerable to drought-induced embolism than angiosperm trees - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Accéder directement au contenu
Article Dans Une Revue Plant Physiology Année : 2016

Herbaceous angiosperms are not more vulnerable to drought-induced embolism than angiosperm trees

Résumé

The water transport pipeline in herbs is assumed to be more vulnerable to drought than in trees due to the formation of frequent embolisms (gas bubbles), which could be removed by the occurrence of root pressure, especially in grasses. Here, we studied hydraulic failure in herbaceous angiosperms by measuring the pressure inducing 50% loss of hydraulic conductance (P50) in stems of 26 species - mainly European grasses (Poaceae).Our measurements show a large range in P50 from -0.5 to -7.5MPa, which overlaps with 94% of the woody angiosperm species in a worldwide, published dataset, and which strongly correlates with an aridity 52 index. Moreover, the P50 values obtained were substantially more negative than the midday water potentials for five grass species monitored throughout the entire growing season, suggesting that embolism formation and repair are not routine and mainly occur under water deficits. These results show that both herbs and trees share the ability to withstand very negative water potentials without embolism formation in their xylem conduits during drought stress. In addition, structure function trade-offs in grass stems reveal that more resistant species are more lignified which was confirmed for herbaceous and closely related woody species of the daisy group (Asteraceae). Our findings could imply that herbs with more lignified stems will become more abundant in future grasslands under more frequent and severe droughts, potentially resulting in lower forage digestibility.

Mots clés

Fichier principal
Vignette du fichier
Lens_PlantPhysiology_1.pdf (9.25 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-02638426 , version 1 (28-05-2020)

Identifiants

Citer

Frederic Lens, Catherine Picon-Cochard, Chloé E. L. Delmas, Constant Signarbieux, Alexandre Buttler, et al.. Herbaceous angiosperms are not more vulnerable to drought-induced embolism than angiosperm trees. Plant Physiology, 2016, 172 (2), pp.661-667. ⟨10.1104/pp.16.00829⟩. ⟨hal-02638426⟩
39 Consultations
77 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More