Plan apo na 0

To quantify GFP fluorescence in nuclei, images were obtained with a LSM780 confocal microscope (Carl Zeiss, France) using a × 20 dry objective (Plan Apo NA 0.80). GFP was excited with the Argon laser (488 nm), and emitted light was collected between 493 and 538 nm with a pinhole setting of 1.51 a.u.
All nuclei were imaged using the same conditions of gain, offset and resolution (with zoom set to 3), at a constant distance (350 μm) from the root tip. A Z-stack of 15 images (separated by 1 μm distance) imaged representative nuclei on the surface of the root. Images were acquired in 16 bits using Zen black software (Zen black 2012 SP2 Version 11.0), then converted to a maximal projection image. Average nuclei fluorescence intensities were quantified using the Zen blue software (Zen 2 blue edition, version 2.0.0.0), by drawing identical ROI (region of interest) over 3–10 visible (in focus) nuclei for each maximal projection image.

Images were collected on a Zeiss LSM780 confocal microscope (Carl Zeiss, https://www.zeiss.com/) using a ×20 dry objective (Plan Apo NA 0.80). The GFP was excited with an Ar ion laser (488 nm). Emitted light was collected from 493 to 538 nm for GFP, using the MBS 488 filter. All nuclei were imaged using the same conditions of gain, offset and resolution and with a pinhole setting of 1 a.u. The quantification of GFP fluorescence was carried out as follows: a Z‐stack of nine images (separated by a distance of 1.8 μm) imaged representative nuclei on the surface of the root. Images were acquired in 12 bits using Zen black software (SP2 v.11.0, 2012, Carl Zeiss), then converted to a maximum projection image. The average nuclear fluorescence intensities were quantified using Zen blue software (Zen 2 blue edition, v.2.0.0.0, Carl Zeiss), by drawing identical regions of interest. A 120 μm × 60 μm rectangle was defined at 200 μm from a root tip (roughly in the transition zone), in which a region of interest (6 μm × 6 μm) inside each nucleus was defined for the measurement of fluorescence.