2.8 Confocal microscopy
Al-morin fluorescence in the cross-sections of different root zones was
examined according to Klug et al. (2011). The two-day-old plants treated
with 5 μM Al for 2, 6, 24, and 72 h were washed with distilled water to
remove hydroponic solution from the root surface, and 10-mm of root tips
were excised, and immediately embedded in 5% (w/v) low-gelling point
agarose (Fluka, Switzerland) at 35 °C. The embedded root tips were
sectioned using a razor blade and incubated with 30 µM morin (Sigma,
USA) for 1 h under darkness. Confocal imaging of Al-morin fluorescence
was performed using a Leica Laser Scanning Confocal Microscope SP5
(Leica Microsystems, Germany) equipped with a 20× water immersion
objective. The excitation wavelength was set at 405 nm, and the emission
was detected at 490-510 nm. Images were processed with LAS AF software
(Leica Microsystems, Germany) and were quantified using Image J software
(NIH, USA).