Regulation of the Transfer of TI Plasmids of Agrobacterium tumefaciens

Abstract
Summary: Octopine-utilizing agrobacteria could be distinguished from non-utilizers on a solid medium containing octopine as the only added nitrogen source if a pH indicator such as bromothymolblue were present. On green bromothymolblue plates, octopine-utilizing strains formed orange-yellow colonies, while those of non-utilizers were translucent. Strains could be tested for utilization of other nitrogen sources such as nopaline by substituting these for octopine in the same medium.