Agriculture Reference
In-Depth Information
BIOLOGY
Moths overwinter in various sheltered situations
and emerge in April. Larvae feed singly on the
upper surface of leaves, beneath a silken web.
They also feed within folded leaves. Pupation
occurs in dense, white cocoons formed on the
underside of a leaf or on dead leaves on the
ground. Adults emerge in July or early August.
A second generation of larvae feed in late sum-
mer and these produce adults in the autumn.
Fig. 273 Forewing of cocksfoot moth, Glyphipterix
simpliciella (x!5).
DESCRIPTION
Adult 11-13 mm wingspan; forewings brown
to greyish-brown with dark, wavy markings;
hindwings greyish-brown. Larva up to 14 mm
long; body yellow to pale green, translucent;
pinacula black and very obvious; head yellowish-
brown.
spot (Fig. 273); hindwings dark grey. Larva up
to 6 mm long; body whitish-green; head and
prothoracic plate black.
Family YPONOMEUTIDAE
(e.g. small ermine moths)
Acrolepiopsis assectella (Zeller)
Leek moth
Family GLYPHIPTERIGIDAE
Glyphipterix simpliciella (Stephens)
Cocksfoot moth
This insect is a local pest of leek; garlic, onion
and shallot are also attacked. The young larvae
form small holes in the furled leaves; older
individuals cause distortion and also graze away
considerable areas of photosynthetic tissue. In-
festations induce secondary rotting of the leaves
and bulbs, and this may result in plant death.
In the British Isles, attacks are usually limited to
the coastal parts of eastern, southern and south-
western England but they are more widespread
in continental Europe, where they extend from
Denmark southwards.
This generally common species occurs on wild
Dactylis glomerata; it is also capable of damaging
seed crops of cultivated cocksfoot. The larvae
hollow out the seeds but infestations are of little
or no importance.
BIOLOGY
Adults occur in late May and June. They often
swarm, in groups of 10 or more, over the
flowerheads of host plants. Eggs are laid at the
base of the seeds and hatch about 2 weeks later.
Larvae, which feed throughout July, at first at-
tack the stamens of the florets; later, they bore
inside the developing seeds. Individuals are fully
grown in about a month. Each then overwinters
in a cocoon spun inside a grass stem. Pupation
occurs in the spring and adults emerge 3-4 weeks
later.
BIOLOGY
Adults overwinter amongst shelter on the
ground and reappear in the spring. Eggs are then
deposited on the leaves of host plants, usually
towards the base. The eggs hatch about a week
later. The larvae then bore through the leaf
sheath into the heart of the plant. They feed for
3-4 weeks, and often mine within the hollow
leaves down to the base of the stem. Fully grown
larvae pupate in loose, net-like cocoons (8-9 mm
long) (Plate 11a) which they spin on the host
plant, in the soil or amongst debris on the
ground. There are several generations annually;
these range from two or three in northerly parts
DESCRIPTION
Adult 7-8mm wingspan; forewings mainly dark
brownish-bronze, ornamented with silvery mark-
ings, five white strigulae on the apical half of the
costa, an oblique white streak and a black apical
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