Abstract
Strain K60 of P. solanacearum cannot stably maintain P-1 incompatibility group plasmids. It is possible to isolate derivatives that receive and maintain these plasmids. This system was used to mutagenize the strain with transposons Tn5, Tn7 and Tn10. In P. solanacearum, Tn5 and Tn10 are transposed with a relatively high frequency (5 .times. 10-6), and 1% of the transposon-harboring clones obtained were auxotrophs. The transposition frequency with Tn7 is low.