AVRDC International Cooperators'
Several species including Myzus persicae, Hyadaphis erysimi and
Leaves are curled, wrinkled, or cup-shaped. Plants in all
growth stages can be damaged. With severe infestations the
leaves wilt and the entire plant dies.
Piercing-sucking mouthparts. They are small, soft-bodied,
and pear-shaped. They vary from yellow to green to black.
Some have transparent wings and prominent eyes. Note the
small tubes arising from either side of the back of their
bodies (tail region).
Where to Look
Select leaves that are beginning to curl, show signs of wilting,
or are partially dried up. Look within the cupped leaf for
colonies of the pear-shaped insects. They vary in size from 2
to 4 mm in length.
Aphids have continual generations and many hosts. When
populations on one plant are high, winged forms are
produced that fly to adjacent plants to establish new colonies.
Aphid colonies are commonly visited by ants that feed on the
honeydew secreted by the aphids. This honeydew also
serves as food on which a sooty mold grows. Some aphid
species are virus vectors. Many different vegetables serve as
hosts of aphids.
Resistant and susceptible
Tubes at tail end
Typical population on
underside of a leaf
Sooty mold damage
Biological: Natural enemies, such as parasitic wasps and
predators, are usually numerous enough to keep aphid
populations from building to damaging levels. Adults and
larvae of coccinelid beetles and syrphid fly larvae are well-
known predators. Wet weather will cause fungal pathogens to
Cultural: Remove weeds. Destroy and remove crop residues
immediately after harvest. Aphids are less attracted to
mulched plantings since host plants are less highlighted
compared to a bare-soil background.
Chemical: Soap sprays may be used, but th