Agriculture Reference
In-Depth Information
Fig. 227
Immature stages of apple blossom weevil,
Anthonomus pomorum:
(a) larva; (b) pupa (xlO).
Fig. 228
Apple bud weevil,
Anthonomus piri
(x!2).
Anthonomus piri
Kollar
Apple bud weevil
In continental Europe, this weevil is an impor-
tant pest of pear. In the British Isles, it is re-
stricted to apple but is found only rarely. Adults
are on average slightly larger than those of
Anthonomus pomorum
(above) and are reddish-
brown with a straight, rather than a V-shaped,
elytral mark
(Fig. 228).
The yellowish-white lar-
vae develop within unopened vegetative buds
during the spring.
following spring. Damage to strawberry crops
tends to be most significant on cultivars that pro-
duce few blossoms; more vigorous cultivars
usually compensate for early loss of blossoms.
Infestations on
Rubus
hosts occur somewhat
later in the year than those on strawberry.
Ceutorhynchus assimilis (Paykull)
Cabbage seed weevil
Anthonomus rubi
(Herbst)
Strawberry blossom weevil
This weevil is a generally common pest of
brassica seed crops; economic damage also
occurs on certain vegetable brassicas.
Brassica
seed crops:
adult feeding is of no direct signifi-
cance, although feeding punctures may allow fe-
male brassica pod midges,
Dasineura brassicae
(see p. 171) to deposit eggs into pods. Most dam-
age is caused by the larvae, which feed within the
pods on the developing seeds; each larva (typi-
cally one per infested pod) usually destroys sev-
eral seeds. Attacks are particularly common on
oilseed rape and brown mustard (white mustard
is immune to attack) but crops are often able
to fully compensate for any damage caused.
Vegetable brassicas:
most significant damage is
caused in summer, from mid-July to mid-August,
by adults reared on nearby rape crops. Such indi-
viduals may feed on the buttons of Brussels
This mainly black (2-4 mm long) weevil is a lo-
cally important pest of strawberry. Infestations
also occur on
Rubus,
including cultivated black-
berry and raspberry. The adults, that are present
in greatest numbers in late May or early June,
cause minor damage by drilling small round
holes through the leaves and flower petals. Eggs
are deposited singly in unopened blossom buds.
The egg-laying female also partially severs the
blossom stalk (cf. damage caused by strawberry
rhynchites,
Rhynchites germanicus,
p. 151). Eggs
hatch within a week and the larvae feed for up to
2 weeks before pupating. Young adults emerge
about 2 weeks later. They feed briefly on host
plants and then hibernate, reappearing in the
