Hydathode trichomes actively secreting water from leaves play a key role in the physiology and evolution of root-parasitic rhinanthoid Orobanchaceae

0447992 - BÚ 2016 RIV GB eng J - Článek v odborném periodiku
Světlíková, P. - Hájek, Tomáš - Těšitel, J.
Hydathode trichomes actively secreting water from leaves play a key role in the physiology and evolution of root-parasitic rhinanthoid Orobanchaceae.
Annals of Botany. Roč. 116, č. 1 (2015), s. 61-68. ISSN 0305-7364. E-ISSN 1095-8290
Institucionální podpora: RVO:67985939
Klíčová slova: active water transport * parasite * water regime
Kód oboru RIV: EH - Ekologie - společenstva
Impakt faktor: 3.982, rok: 2015

We measured respiratory cost of active water secretion by hemiparazitic Rhinanthus alectorolophus. Night-time rates of respiration and transpiration and the presence of guttation drops were positively correlated, which is a clear indicator of hydathode trichome activity. Subsequent physiological measurements on older, flowering plants indicated neither intense guttation nor the presence of correlations. This study provides the first unequivocal evidence for the physiological role of the hydathode trichomes in active water secretion in the rhinanthoid Orobanchaceae. Depending on the concentration of organic elements calculated to be in the host xylem sap, the direct effect of water secretion on carbon balance ranges from close to neutral to positive. However, it is likely to be positive in the xylem-only feeding holoparasites of the genus Lathraea, which is closely related to Rhinanthus. Thus, water secretion by the hydathodes might be viewed as a physiological pre-adaptation in the evolution of holoparasitism in the rhinanthoid lineage of Orobanchaceae.
Trvalý link: http://hdl.handle.net/11104/0249751