Numerical analysis of phenotypic features of Pseudomonas solanacearum strains isolated from tobacco and other hosts in South Africa.
A total of 46 strs of P. solanacearum from South Africa and 13 reference strs was subjected to numerical phenetic analysis using 55 unit characters. Data were analysed by applying unweighted pair-grouping clustering on the simple matching (Ssm) coeff. At 85% Ssm, 3 phenons and 2 solitary strs were distinguished. Phenons 1, 2 and 3 corresponded, respectively, with biovars III, I and II. All strs in phenons 1 and 2 were assigned to race 1 and those of phenon 3 to race 3. At 95% Ssm 3 groups were recognized within each phenon. None of the reference strs corresponded with South Africa strs in all of the features examined. Apart from 5 potato strs of group 3A, all South African strs of P. solanacearum were assigned to groups 1A and 1B of phenon 1. Local race 1 tobacco strs were highly virulent on other host species tested.