TY  - JOUR
A1  - Rudolph, Nicole
A1  - Voss, Sebastian
A1  - Moradi, Ahmad B.
A1  - Nagl, Stefan
A1  - Oswald, Sascha Eric
T1  - Spatio-temporal mapping of local soil pH changes induced by roots of lupin and soft-rush
JF  - Plant and soil
N2  - The rhizosphere is a dynamic system strongly influenced by root activity. Roots modify the pH of their surrounding soil causing the soil pH to vary as a function of distance from root surface, location along root axes, and root maturity. Non-invasive imaging techniques provide the possibility to capture pH patterns around the roots as they develop.
 We developed a novel fluorescence imaging set up and applied to the root system of two lupin (Lupinus albus L., Lupinus angustifolius L.) and one soft-rush (Juncus effusus L.) species. We grew plants in glass containers filled with soil and equipped with fluorescence sensor foils on the container side walls. We gained highly-resolved data on the spatial distribution of H+ around the roots by taking time-lapse images of the samples over the course of several days.
 We showed how the soil pH in the vicinity of roots developed over time to different values from that of the original bulk soil. The soil pH in the immediate vicinity of the root surface varied greatly along the root length, with the most acidic point being at 0.56-3.36 mm behind the root tip. Indications were also found for temporal soil pH changes due to root maturity.
 In conclusion, this study shows that this novel optical fluorescence imaging set up is a powerful tool for studying pH developments around roots in situ.
KW  - Acidification
KW  - Alkalization
KW  - Exudates
KW  - Fluorescence imaging
KW  - Optical sensors
KW  - pH mapping
KW  - Rhizosphere
Y1  - 2013
U6  - https://doi.org/10.1007/s11104-013-1775-0
SN  - 0032-079X
VL  - 369
IS  - 1-2
SP  - 669
EP  - 680
PB  - Springer
CY  - Dordrecht
ER  -