root culture

[Maurizio Chiurazzi]

Dear netters,
Does anyone has experience with root culture conditions?
Suddendly I'm getting in trouble with my transgenics root cultures obtained
after A. rhizogenes infection. They are growing very slow and with no
branching of lateral roots. Furthermore, they start to become dark in the
region of the central stele after awhile. I tried to change the vitamins
and MS powder batch with no success. I previously grew my transgenic roots
in MS/2 medium, + 3% sucrose + vitamins, 1.2% agar and this conditions were
fine.
Any advice will be welcome
Maurizio