A
single
gene
controls
the
hypersensitive
response
of
Hawaii
7981
to
race
3
(T3)
of
the
bacterial
spot
pathogen
.
Scott,
J
.
W
.
1
,
Stall,
R
.
E
.
2
,
Jones,
J
.
B
.
1
,
and
Somodi,
G
.
C
.
1
1
Gulf
Coast
Research
&
Education
Center,
University
of
Florida,
5007
60th
SL
E
.
,
Bradenton,
FL
34203
2
Plant
Pathology
Dept
.
,
University
of
Florida,
2515
Fifield
Hall,
P
.
O
.
Box
110680,
Gainesville,
FL
32611
Presently
three
races
of
the
bacterial
spot
pathogen
Xanthomonas
campestris
pv
.
vesicatoria
infect
tomato
.
These
are
T1,
T2,
and
T3
(Bouzar
et
aL,
1994)
.
Hawaii
7998
is
resistant
to
T1
with
multigenic
control
of
the
hypersensitive
reaction
and
field
resistance
(Wang
et
al
.
,
1994)
.
We
recently
reported
that
Hawaii
7981
had
a
hypersensitive
response
and
a
high
level
of
field
resistance
to
the
T3
strain
(Scott
et
al
.
,
1995)
.
Plants
of
Hawaii
7981,
Fla
.
7060
(susceptible)
and
F
1
,
F
2
,
and
BC
generations
derived
from
these
two
inbreds
were
injected
with
10
8
cfu/ml
of
the
T3
strain
and
rated
for
confluent
necrosis
at
24
and
48
hr
after
injection
.
This
was
done
at
24
and
32°C
.
No
confluent
necrosis
was
expressed
at
32°C
.
At
24°C
(Table
1)
100%
of
Hawaii
7981,
54%
of
the
backcross
to
Hawaii
7981,
and
22%
of
the
F
2
expressed
confluent
necrosis
at
24
hr
.
At
48
hr
100%
of
the
F,
and
the
backcross
to
Hawaii
7981,
50%
of
the
backcross
to
Fla
.
7060,
and
73%
of
the
F
2
plants
expressed
hypersensitivity
.
The
data
support
control
of
hypersensitivity
to
T3
from
Hawaii
7981
by
a
single
incompletely
dominant
gene
.
Two
experiments
suggest
this
gene
plays
a
major
role
in
field
resistance
(data
not
shown)
.
We
propose
Xv
-
3
as
the
symbol
far
this
gene
.
Literature
Cited:
Bouzar,
H
.
,
J
.
B
.
Jones,
R
.
E
.
Stall,
N
.
C
.
Hodge,
G
.
V
.
Minsavage,
A
.
A
.
Benedict,
and
A
M
.
Alvarez
.
1994
.
Phytopathology
84:663
-
671
.
Scott,
J
.
W
.
,
J
.
B
.
Jones,
G
.
C
.
Somodi,
and
R
.
E
.
Stall
.
1995
.
HortScience
30(3):579
-
581
.
Wang,
J
-
F
.
,
J
.
B
.
Jones,
J
.
W
.
Scott,
and
R
.
E
.
Stall
.
1994
.
Phytopathology
84:702
-
706
.
No navigation control above? Click here!
