Kanamycin/hygromycin B from different sources

[Zhixiang Chen]

Has anyone doing plant transformation noticed whether kanamycin or
hygromycin B from different commercial sources shows difference in potency
for transformant selection?  We are having some problems in tobacco
transformation with hygromycin B purchased from BRL.  Which commercial
source(s) would you recommend to us for these general antibiotics?

Thanks for any information.

Z. Chen
MMBB
University of Idaho
Moscow, ID 83844