Agriculture Reference
In-Depth Information
leaf disease. Unlike many other genera, species
of
Empoasca
overwinter in the adult stage,
individuals typically sheltering on conifers or on
other evergreen plants such as
Hedera helix.
Adults of
E. decipiens
are about 3 mm long and
mainly green, with whitish markings on the head
and thorax.
underside of the leaves. They pass through five
instars before attaining the adult stage.
DESCRIPTION
Adult
3.5-4.3 mm long, mainly yellowish-orange,
marked extensively with black;
elytra
yellowish-
orange with black markings and, usually, a large,
irregular, brown, longitudinal streak.
Nymph
mainly whitish.
Eupterycyba jucunda
(Herrich-Schaeffer)
Potato leafhopper
Eupteryx melissae
Curtis
Chrysanthemum leafhopper
Although associated mainly with
Alnus,
infesta-
tions of this generally common species often oc-
cur during the summer on potato. Infested leaves
become speckled and, sometimes, yellowish or
brown, but damage is usually unimportant.
There are two generations annually. Adults are
4.0-4.5 mm long and mainly greenish or
greenish-yellow, spotted with black, and with a
mainly black abdomen; there are three distinc-
tive black spots on the pronotum and a pair of
black triangles anteriorly on the scutellum.
NOTE Although leafhoppers of various genera are
associated with fruit crops and a wide range of orna-
mental plants, few species are of significance on arable
crops. Various species, however, feed on crops such
as potato and sugar beet; they cause minor foliage
damage but do not transmit viruses.
Infestations of this locally abundant leafhopper
occur on various cultivated plants, including
chrysanthemum, garden mint and sage, individu-
als often inhabiting the upper surface of the
leaves. Infested plants frequently become con-
taminated by cast-off nymphal skins; leaves also
become extensively speckled and such damage is
often of considerable significance. Adults are c.
3 mm long and pale-coloured, with a black abdo-
men and the elytra extensively marked with
greyish- or orange-brown
(Fig. 184).
Hauptidia maroccana
(Melichar)
Glasshouse leafhopper
This polyphagous leafhopper is well established
in glasshouses in northern Europe. It feeds on
the underside of the leaves of cucumber, melon,
tomato and various ornamentals, especially chry-
santhemum and primrose; if conditions are fa-
vourable, infestations may also occur on outdoor
plants, including various weeds. The insects
cause a pale speckling or mottling of infested
leaves
(Plate le).
Attacked plants may be weak-
ened, and seedlings can be killed, but infesta-
tions are rarely of significance.
Eupteryx aurata
(L.)
A potato leafhopper
This generally common leafhopper is associated
mainly with
Urtica
but, during the summer, it
also occurs on various other plants, including
potato and various members of the family
Labiatae. The adults and nymphs cause a yellow-
ing of the foliage; heavy infestations of this
and certain other species of leafhopper (e.g.
Eupterycyba jucunda,
above) may also cause
leaves of potato to wilt, turn brown and die, a
condition known as 'hopper burn'.
BIOLOGY
This species overwinters in the egg stage on
urtica. In summer, eggs are laid in the leaves and
stems of potato, and in those of various other
Fig. 184
Forewing of chrysanthemum leafhopper,
Eupteryx melissae
(x25).
