Kk. Knoche et al., RELATIONSHIP OF PSEUDOMONAS-SYRINGAE PV TABACI RACES TO THE RHIZOSPHERE OF WISCONSIN-GROWN TOBACCO, Plant and soil, 158(1), 1994, pp. 91-97
Isolates of Pseudomonas syringae pv. tabaci, including 21 strains of t
he wildfire pathogen and 2 strains of the angular leafspot pathogen, w
ere isolated from 143 rhizosphere and soil samples collected from 11 t
obacco fields in Wisconsin. These pathogens were isolated by inoculati
ng rhizosphere and soil washings into tobacco leaves and isolating the
bacteria from wildfire or angular leafspot lesions that developed on
the leaves. The wildfire isolates were from the rhizospheres of tobacc
o and Panicum capillare and from soil. While the majority of these wer
e from wildfire-diseased fields, one isolate was from a field without
disease symptoms; both angular leafspot isolates were from fields with
out angular leafspot symptoms. The majority of wildfire isolates were
race 1, but three were race 0, and one was a new race; In three fields
multiple races of wildfire were found. Both angular leafspot isolates
were race 1. Two wildfire and one angular leafspot isolates were from
fields where the cultivars were resistant to the races isolated.