Antibacterial and antifungal activity was investigated for
strains of
Acidovorax
spp.,
Burkholderia
spp.,
Herbaspirillum rubrisubalbicans
and
Ralstonia
solanacearum
; strains representing 118 species and pathovars of
Xanthomonas
were also
tested for phytotoxic capacity. Antibacterial activity was present in all
Burkholderia
spp. except
B. andropogonis
, in biovars II and III of
R. solanacearum
but not in biovars
I and IV, and in two strains of
Xanthomonas.
Little antibacterial activity was
recorded for
Acidovorax
spp. Antifungal activity was expressed by most strains of
A.
avenae
ssp.
avenae
and
A. avenae
ssp.
cattleyae.
Weak or variable antifungal
reactions were given by strains of
A. avenae
ssp.
citrulli
and no activity was expressed
by
A. konjaci.
Most strains of
B. caryophylli, B. cepacia, B. gladioli
pv.
agaricicola,
B. gladioli
pv.
alliicola, B. gladioli
pv.
gladioli
,
B. glumae
and
B. plantari
produced
extensive inhibition zones against
Rhodotorula mucilaginosa.
Strains of
H. rubrisubalbicans
and
R. solanacearum
gave negative, weak or variable reactions. Strains of
Xanthomonas
spp.
exhibited no antifungal activity. In all cases antifungal activity was caused by a low molecular
weight toxin. Three
Xanthomonas
strains exhibited phytotoxic activity. The ecological
implications of these data are discussed