Management of almond mealy bugs (Drosicha dalbergia) in Kashmir


Bhat, A.A.; Koul, V.K.; Bhat, O.K.

Indian Journal of Plant Protection 16(1): 97-98

1988


Mealy bug (Drosicha dalbergia, Green) is one of the most serious pests of apple and almond in Kashmir. Second instar nymphs hibernate in the rhizosphere of its host plant. Activity is resumed during March and partial migration of the insect to the aerial parts of host plant takes place during April-May. All the adults migrate back to the rhizosphere of the host plant during July. The adults and nymphs have been recorded upto the depth of 27 inches. The bugs suck sap from the tender roots, branches and stem of the host plant and weaken it. There is no literature available on the management of this species of mealy bugs. Evaluation of some insecticides for its management was therefore carried out under high hill conditions.

Indian
J.
of
Plant
Prot.
16:
97-98,
1988
MANAGEMENT
OF
ALMOND
MEALY
BUGS
(DROSICHA
DALBERGIA)
IN
KASHMIR
A.A.
BHAT,
VIJAY
K.
KOUL
AND
O.K.
BHAT
Division
of Entomology,
S.K.
University
of
Agricultural
Sciences
&
Technology,
Shalimar-191
121,
Jammu
and
Kashmir.
Mealy
bug
(Drosicha
dalbergia,
Green)
is
one
of
the
most
serious
pests
of
apple
and
almond
in
Kashmir
(Malik
et
al.,
1972).
Second
instar
nymphs
hibernate
in
the
rhizosphere
of
its
host
plant.
Activity
is
resumed
during
March
and
partial
migra-
tion
of
the
insect
to
the
aerial
parts
of
host
plant
takes
place
during
April-May.
All
the
adults
migrate
back
to
the
rhizosphere
of
the
host
plant
during
July.
The
adults
and
nymphs
have
been
recorded
upto
the
depth
of
27
inches.
The
bugs
suck
sap
from
the
tender
roots,
branches
and
stem
of
the
host
plant
and
weaken
it.
There
is
no
literature
available
on
the
manage-
ment
of
this
species
of
mealy
bugs.
Evalua-
tion
of
some
insecticides
for
its
manage-
ment
was
therefore
carried
out
under
high
hill
conditions.
The
experiments
were
conducted
in
a
predominantly
almond
growing
belt
of
Anantnagh
(Tral)
in
a
private
orchard.
Twenty
one
almond
trees
of
almost
same
age
and
vigour
were
selected
and
marked.
The
experiments
were
laid
out
in
completely
randomized
block
design
with
seven
treat-
ments
replicated
thrice.
Phorate
granules
(10G)
at
the
rate
of
20,25
and
30
gms.
per
plant
were
applied
around
the
collar
of
the
plant
and
mixed
with
the
soil
up
to
the
depth
of
4-6
inch,
whereas
quinal-
phos,
monocrotophos
and
dimethoate
at
1
ml
per
lit
of
water
was
applied.
Emuls-
ions
were
used
both
as
soil
drench
and
aerial
sprays,
using
15
to
181itres
of
spray
solution
per
tree.
The
number
of
live
bugs
were
counted
on
per
meter
branch
in
four
geographical
directions
of
each
tree
and
for
underground
population
number
of
live
bugs
was
count-
ed
before
and
after
3
and
7
days
of
treat-
ment
application.
The
statistical
analysis
was
done
following
Snedecor
and
Cochran
(1974).
The
data
(Table
1)
revealed
that
phorate
(10
G)
at
20,25
and
30
gins.
per
tree
was
ineffective
in
supressing
the
bug
infestation
on
the
aerial
parts
of
the
plants
irrespective
of
the
after
treatment
periods.
However,
soil
application
of
phorate
at
the
same
rates
were
found
most
effective
in
reducing
the
subterranean
population.
Quinalphos,
monocrotophos
and
dime-
thoate
as
soil
drench
and
aerial
spray
reduced
the
bug
infestation
significantly
both
on
aerial
as
well
as
underground
populations.
Larka
et
al.,
(1980)
also
reported
quinalphos
(0.075
%)
very
effe-
ctive
against
first
instar
nymphs
of
Drosicha
mangiferae.
From
the
results
it
is
concluded
that
the
granular
application
of
phorate
(10G)
at
20
gms
per
plant
if
applied
in
March
before
hibernating
nymphs
move
to
the
aerial
parts
of
the
plant
can
keep
the
pest
population
under
check.
Granular
appli-
cation
is
safer,
as
it
does
not
directly
effect
the
activity
of
natural
enemies,
pollinators
and
is
also
economical
since
it
does
not
involve
the
use
of
any
plant
protection
equipment.
In
case
soil
application
of
phorate
(10G)
is
not
possible,
the
emsulsion
formulations
evaluated
during
the
course
98
Bhat
et
al.
TABLE
1.
Relative
effectiveness
of
some
chemicals
against
mealy
bugs
(Drosicha
delbergia.
G)**
Mean
no.
of
live
Mean
%
mortality
Treatments
Conc/Dosage
mealy
bugs/meter
beneath
collar
branch
3
DAT
7
DAT
3
DAT
7
DAT*
Phorate
(Thimet
10
G)
20
gm/plant
2.3
2.1
76.2
82.4
Phorate
(Thimet
10
G)
25
gms/plant
2.4
2.2
70.0
82.4
Phorate
(Thimet
10
G)
30
gms/plant
2.1
2.0
84.4
85.1
Quinalphos
(Exalux
35
EC)
1
ml/lit
1.5
1.1
60.7
67.2
Monocrotophos(Nuvacron
40
EC)
1
ml/lit
1.3
1.2
66.0
77.2
Dimethoate(Rogor
35
EC)
1
ml/lit
1.4
1.3
74.2
82.3
Control(water
application)
2.1
2.1
25.6
32.5
CD
(P
=
0.05)
0.4487
0.3588
11.26
8.38
*
DAT
indicates
days
after
treatment.
**
Pooled
data
of
present
studies
can
be
used
as
aerial
spray
or
soil
drench.
However,
further
studies
to
evaluate
the
use
of
non
conven-
tional
methods
of
the
pest
management
need
to
be
tried.
REFERENCES
Larka,
R.K.
Zile.
Singh
and
W.S.
Kharub,
1980.
Efficacy
of
some
insecticides
as
drench
and
foliar
spray
against
mango
mealy
bug
(Drosicha
mangifera
G)
in
Haryana.
Haryana
Agri.
Univ.
J.
Res.
10:50-56.
Malik,
A.R.,
Punjabi,
A.A.
and
A.A.
Bhat,
1972.
Insect
and
non-insect
pests
of
Kashmir.
Hor-
ticulturist
(J
&
K)
III
(1-3):29-44.
Snedecor,
W.G.
and
G.W.
Cochran,
1967.
Statisti-
cal
Methods.
Oxford
and
IBH
publishing
Com-
pany,
New
Delhi.
Received
:
10-8-1987
Accepted
:
15-12-1987