Agriculture Reference
In-Depth Information
shaped.
Nymph
pale yellowish-green to brown-
ish, with a distinct orange mark on the abdomen
and a pair of black spots on each thoracic
segment.
Plesiocoris rugicollis
(Fallen)
Apple capsid
Nowadays, this locally distributed capsid is a
relatively minor pest of apple. Leaves and shoots
are punctured, and tissue becomes distorted and
marked with necrotic spots. Attacked fruitlets
develop corky scars and may drop prematurely.
Apple capsid will also damage the foliage of cur-
rant and gooseberry bushes.
BIOLOGY
Adults are active in late June and July, when
eggs are laid in the bark of apple trees. The eggs
hatch in the following spring. The very active
nymphs then attack the foliage and blossom
trusses. Developing fruitlets are also attacked.
Maturity is reached after five nymphal stages,
there being just one generation annually.
Fig. 182
Common green capsid,
Lygocoris pabulinus
(x8).
Most damage is caused to seedlings and to the
growing points or young leaves of older hosts.
Infestations are especially important on sugar
beet and often result in the development of
multiheaded plants. Damage may also occur on
strawberry, attacked fruits becoming malformed
and, hence, unmarketable.
DESCRIPTION
Adult
5.5-6.8 mm long, mainly green;
legs
yel-
low;
elytra
often with a yellow margin;
pronotum
with distinct callosities (cf. common green
capsid,
Lygocoris pabulinus,
p. 97).
Nymph
yellowish-green;
antennae
tipped with reddish-
brown.
BIOLOGY
This species overwinters in the adult stage,
amongst debris or under leaf litter in hedgerows,
dykes and other situations. The bugs appear in
the early spring and immediately begin to feed;
they often then invade field crops. The adults are
very active and scurry or fly away when dis-
turbed. Eggs are laid in the stems or other parts
of host plants, usually in May. Nymphs appear
from late May or early June onwards. They pass
through five instars and take up to 2 months to
mature. In most regions there are two genera-
tions annually, and second-generation nymphs
reach adulthood in September or October.
Family CERCOPIDAE (froghoppers)
Cercopis vulnerata
Illiger in Rossi
Red
&
black froghopper
This widely distributed and generally common
univoltine insect is a minor pest in orchards and
hop gardens. The adults pierce the upper surface
of the foliage to form small greenish-yellow
marks that eventually turn brown. This symp-
tom, which was once thought to be due to a
fungal pathogen, is often known as 'angular leaf
spot'. On pear, damage is restricted to the
fruitlets and fruit stalks, these becoming marked
DESCRIPTION
Adult
up to 6 mm long, extremely variable in
appearance but usually dark brown to reddish-
brown.
Egg
1mm long, creamish-white, flask-
