TGC
REPORT
No
.
31,
1981
RESEARCH
NOTES
2
PART
I
RESEARCH
NOTES
Avdeyev,
Y
.
I
.
Pleitropic
effect
of
Crack
-
resistant
forms
were
not
found
y
gene
.
amongst
more
than
20
varieties
with
the
y
gene
(colorless
fruit
epidermis;
pink
fruit
color)
.
All
y
segregants
in
the
F
2
and
F
3
generations
of
crosses
between
pink
-
fruited
varieties
and
crack
-
resistant
red
-
fruited
lines
were
also
susceptible
.
Presumably
y
has
a
pleiotropic
effect
on
susceptibility
to
cracking
.
This
conclusion
is
confirmed
by
experiments
with
spontaneous
mutants,
selected
for
10
years
from
vars
.
VF
-
145
-
F5,
Epoch,
and
Niskorosly
Shtambovy
.
In
contrast
to
the
high
crack
resistance
of
these
varieties,
their
respective
y
mutants
were
crack
-
susceptible
and
had
less
mechanical
firmness
--
a
condition
that
might
be
connected
with
diminished
synthesis
of
pectins
.
The
following
table
shows
data
that
characterize
one
of
these
mutants
.
Two
phenotypically
distinguishable
classes
of
lanceolate
-
leaf
mutants
were
observed
in
the
progeny
of
78L
Farrell,
M
.
A
homozygous
-
viable
lance
-
olate
-
leaf
mutant
.
1101
-
308,
a
90%
sterile
M
1
(EMS)
plant
of
25%
normal
(cv
.
VFNT
Cherry)
diameter
.
One
has
extremely
narrow
leaves
with
an
abundance
of
axillary
shoots
("La
-
like/La
-
like"),
while
the
other
has
elongated
leaves
and
is
intermediate
in
axillary
shoot
number
and
flower
size
("La
-
like/+")
.
A
stunted
yellow
-
virescent
mutant
with
tiny
leaves
and
a
congested
branch
habit
(stemming
from
foreshortened
internodes)
assorted
independently
of
the
La
-
like
progeny
of
this
plant,
as
seen
in
the
class
distributions
--
104
L/L,
+
255
L/+,
+
:
130
+/+,
+
:
32
L/L,
mutant
:
85
L/+,
mutant
52
+/+,
mutant
(contingency
chi
-
square
=
0
.
29)
.
A
29
.
30
contingency
chi
-
square
value
for
the
F
2
:
La
-
like
x
not
(LA
1164)
segregation
suggests
linkage
with
this
chromosome
7
marker
.
(Linkage
is
also
suggested
by
the
contingency
chi
-
square
value
of
5
.
49
for
the
La
-
like
x
var
segregation
.
)
The
product
method
predicts
an
La
-
like
--
not
linkage
of
11
.
6
+
4
.
3
cM,
emphasizing
the
requirement
for
