Aphids are small plant sap-sucking insects with a high reproductive capacity. Therefore, many aphid species are among the most destructive pests in horticulture, agriculture, forestry, public green and gardens.
Depending on the species, aphids can cause various degrees of damages to crops:
they extract nutrients from the plant, which reduce plant growth, cause leave deformation or even wilting.
the excess sugar they absorb is secreted as honeydew, making the leaves and fruits sticky. Sooty mold can grow on the secreted honeydew and will foul the plant. Photosynthesis may be affected. Sticky and fouled plants and fruits are unmarketable.
they can transmit toxic substances to the plant through their saliva, causing deformation of the growing tips of infected plants
they can transmit viruses, such as the cucumber mosaic virus (CMV)
During spring and summer conditions, an aphid population consists of viviparous females and their reproduction is continuously asexual. This means that progenies are identical to their mother and are born instead of hatching from eggs. The development of new offspring starts immediately after an aphid is born. A female aphid can produce up to 100 progeny. As a consequence of these reproductive characteristics, an aphid population can grow very fast reaching alarming densities.
The most common aphid species are:
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Aphis gossypii |
Myzus persicae |
Myzus nicotianae |
Macrosiphum euphorbiae |
Aulacorthum solani |
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cotton aphid |
green peach aphid |
tobacco aphid |
potato aphid |
foxglove aphid |
