troubleshooting arabidopsis growth on agar plates

[rob_shih]

Hi,
I am experiencing a weird trait in my WT columbia Arabidopsis where their roots are for the most part all growing away from the media.
I am just doing a simple experiment in seeing which conditions grow better for the lab in varying MS and sucrose levels.
each media contains:
0-3% sucrose
.5-1x MS pH 5.7
1 g/L MES buffer
.8% phytagar
and they were plated in normal circular petridishes placed in a cold 4 deg room for 3 days before I put them in a plant growth room laid flat.
I saw this weird root growth trait (where roots should be growing either into the agar or at least on top, if agar is too hard) about 7 days into development and 3 weeks later it is more so where they are growing upwards all over the place on top of the agar.
thanks
-Robert

[danfive]

Happened to me too, but I had kanamycin in the media and was selecting for Kanamycin Resistant strains.

I planted and grew many thousands of them, they are fine healthwise--no clue about the cause of weird seedling root growth. I do suspect that as the thickness of the poured agar media increases you see less of the surface growth.

I think the frequency diminished with time (I got more experience) plating them. Do you keep them in Dark overnight before fridge for 3days (I did that).

If you pour your own plates try increasing the amount poured.

[ASAR]

yes that happens when the agar is too thin. If testing it for root growth on various conc of sucrose... try plating in square plates and stand it vertical. this will allow the roots to grow and u can measure them more easily.