TY  - JOUR
AU  - Lechthaler, Silvia
AU  - Robert, Elisabeth M. R.
AU  - Tonné, Nathalie
AU  - Prusova, Alena
AU  - Gerkema, Edo
AU  - Van As, Henk
AU  - Koedam, Nico
AU  - Windt, Carel
TI  - Rhizophoraceae Mangrove Saplings Use Hypocotyl and Leaf Water Storage Capacity to Cope with Soil Water Salinity Changes
JO  - Frontiers in Functional Plant Ecology
VL  - 7
SN  - 1664-462X
CY  - Lausanne
PB  - Frontiers Media88991
M1  - FZJ-2016-04382
SP  - 895
PY  - 2016
AB  - Some of the most striking features of Rhizophoraceae mangrove saplings are their voluminous cylinder-shaped hypocotyls and thickened leaves. The hypocotyls are known to serve as floats during seed dispersal (hydrochory) and store nutrients that allow the seedling to root and settle. In this study we investigate to what degree the hypocotyls and leaves can serve as water reservoirs once seedlings have settled, helping the plant to buffer the rapid water potential changes that are typical for the mangrove environment. We exposed saplings of two Rhizophoraceae species to three levels of salinity (15, 30, and 0–5‰, in that sequence) while non-invasively monitoring changes in hypocotyl and leaf water content by means of mobile NMR sensors. As a proxy for water content, changes in hypocotyl diameter and leaf thickness were monitored by means of dendrometers. Hypocotyl diameter variations were also monitored in the field on a Rhizophora species. The saplings were able to buffer rapid rhizosphere salinity changes using water stored in hypocotyls and leaves, but the largest water storage capacity was found in the leaves. We conclude that in Rhizophora and Bruguiera the hypocotyl offers the bulk of water buffering capacity during the dispersal phase and directly after settlement when only few leaves are present. As saplings develop more leaves, the significance of the leaves as a water storage organ becomes larger than that of the hypocotyl.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000378593500001
C6  - pmid:27446125
DO  - DOI:10.3389/fpls.2016.00895
UR  - https://juser.fz-juelich.de/record/817739
ER  -