Agriculture Reference
In-Depth Information
nating crops. Infested leaves are often daubed
with sticky, black excrement.
BIOLOGY
Adults overwinter in sheltered situations in fields
or hedges, or at the edges of copses or open
woodlands. They appear in the spring and feed
on various plants before migrating to beet crops.
Eggs are then deposited in the soil in association
with host plants, mainly in April, May or June,
each female laying about 100-120. The eggs
hatch about a week later. Larvae then feed on
the foliage for up to 3 weeks; they may also at-
tack the plant roots. Fully grown larvae wander
away from host plants and eventually pupate in
the soil, close to the surface, each in an earthen
cell. New adults emerge about 2 weeks later and
almost immediately seek overwintering quarters.
The period of egg laying is protracted and all
stages of the pest may occur together; there is,
however, just one generation annually.
Fig. 201
Beet carrion beetle,
Aclypea opaca
(x6).
DESCRIPTION
Adult
9-12 mm long, flattened and broad-
bodied, dull black, clothed in short golden-
brown hairs;
elytra
finely punctured and with
three ornate longitudinal ribs
(Fig. 201). Egg
shiny yellowish-white, spherical, 1-2 mm
across.
Larva
up to 15 mm long;
body
mainly
black and shiny; somewhat woodlouse-like, with
prominent, laterally flanged tergites and elon-
gate processes on the last abdominal tergite;
an-
tennae
long, 3-segmented
(Fig. 202).
Family SCARABAEIDAE
(chafers, dung beetles, etc.)
Amphimallon solstitialis
(L.)
Summer chafer
Fig. 202
Larva of beet carrion beetle.
Aclypea opaca
(x5).
Larvae of this polyphagous, southerly distrib-
uted species often attack beet, cereals, grasses,
potato and various horticultural plants. They
sever the roots or bore into tubers or tap roots
and, particularly in their second summer, are ca-
pable of causing considerable damage. Attacks
are most likely to occur where crops are planted
in recently ploughed-up grassland.
BIOLOGY
Adults occur in June and July, and are particu-
larly active on warm evenings. The eggs, which
are laid in the soil, hatch after several weeks. The
