Biology Reference
In-Depth Information
Aphis fabae
Scopoli (
62-63
)
Black bean aphid
An often major pest of cultivated beans and ornamental
plants. Hosts include guelder-rose (
Viburnum opulus
),
mock orange (
Philadelphus coronarius
) and spindle
(
Euonymus
), and herbaceous plants such as
Clematis
,
Dahlia
, poppy (
Papaver
), nasturtium (
Tropaeolum
),
pot marigold (
Calendula officinalis
) and
Yucca
.
Cosmopolitan. Present throughout Europe.
may also develop in greenhouses on hosts such as
Chrysanthemum
. In the autumn, there is a return
migration to the primary host where, following a sexual
phase, winter eggs are eventually laid. In favourable
situations, aphids may also survive the winter on
herbaceous hosts.
DAMAGE
Primary hosts:
spring infestations cause considerable
curling of leaves on the new shoots, and spoil the
appearance of bushes long after colonies have died out.
Secondary hosts:
leaves may be curled, but infestations
on the buds and flower stalks are usually more
important as these affect the quality, flowering potential
and appearance of plants.
DESCRIPTION
Apterous female:
1.5-2.9 mm long; black to blackish
brown or blackish green, often with whitish patches of
wax on the abdomen; antennae much shorter than body;
siphunculi dark and of moderate length; cauda blunt and
finger-shaped.
Alate:
1.8-2.7 mm long; mainly black,
often with noticeable patches of white wax.
Nymph:
black to blackish brown or blackish green, often with
distinctive patches of white wax.
Aphis gossypii
Glover (
64-65
)
Melon & cotton aphid
Generally common on greenhouse ornamentals such
as
Begonia
, calla lily (
Zantedeschia aethiopica
),
Chrysanthemum
and
Cineraria
. Virtually cosmopolitan.
Widely distributed in Europe.
LIFE HISTORY
The winter is usually passed in the egg stage on spindle
bushes, especially European spindle (
Euonymus
europaeus
), but also on other primary (winter) hosts
such as guelder-rose and mock orange. Eggs hatch in
the early spring, and colonies of aphids then develop on
the young leaves and shoots. Winged forms appear in
May or June and these disperse to various herbaceous
hosts, colonies on the primary host then dying out.
Breeding on these secondary (summer) hosts continues
throughout the summer, with the frequent production
of winged forms and further spread to other summer
hosts. Colonies are ant-attended, and are often common
in July and August on outdoor ornamentals; colonies
DESCRIPTION
Apterous female:
1.4-2.0 mm long; very dark green or
bluish green, sometimes mottled yellowish green;
siphunculi relatively short and dark.
Alate:
1.1-2.1 mm
long; head and thorax dark; abdomen marked with dark
spots.
LIFE HISTORY
This subspecies breeds continuously under protection
(where it is often associated with members of the
Cucurbitaceae, including vegetable crops) but is
62
63
62
Colony of black bean aphid (
Aphis fabae
) on
Clematis
.
63
Black bean aphid (
Aphis fabae
) damage to leaves of
Euonymus
.
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