Sitobion avenae

Sitobion avenae (Fabricius)

Taxonomic placing: Insecta, Hemimetabola,Hemiptera, Sternorrhyncha, Aphidoidea, Aphididae.

Common name: Grain aphid.

Geographical distribution: The grain aphid occurs throughout Europe, Asia, West Africa, America and Japan.

Host plants: Various Poaceae (Gramineae), including cultivated and wild cereal grasses.

Morphology: Body of apterous females is green or yellow-brown, 2-3 mm in length. The antennae are longer than the body, and the siphunculi are black, about twice as long as the cauda. Winged females have a brown-red thorax and green abdominal segments.

Economic importance. The pest causes much damage to wheat, barley, rye, oats, sorghum and maize, resulting in great yield reductions. In addition, the insect excretes honeydew which is colonized by sootymold fungi, as well as being a vector of the barley yellow dwarf virus (BYDV), which affects crops world-wide.

Life cycle. This species usually develops on various grasses, but in rare cases and in colder climates may also live on Rubus. Most populations are anholocyclic, giving birth parthenogenetically only to asexual morphs. A female produces 20-40 nymphs which overwinter; sometimes already as apterous adults. Their life span takes about 4-10 weeks. A small part of the population is holocyclic. Some of these individuals give birth to males and females that mate, producing about a dozen eggs which overwinter and hatch during next spring. Winged forms appear as the host plants begin to dry, or when populations are abundant, and depart to form new colonies on green grasses. The grain aphid develops best at around 20ºC and a relative humidity of 65-80%, and may raise 15-20 annual generations.


Monitoring. An economic injury threshold for various cereal aphids (including the cereal aphid) has been established in England. It consists of five aphids/ear at host flowering.

Horticultural methods. Due to the ability of the pest to develop on many Poaceae, weed grasses should be removed from around fields.

Plant resistance: Efforts are underway to develop wheat strains resistant to S. avenae in several countries, and some Turkish wheat cultivars show resistance to the pest..

Chemical control. Many pesticides kill the pest, but their use is not often required because the aphid is usually controlled by natural enemies, which may be killed by the chemicals.

Biological control: In various parts of the world the pest is usually sufficiently controlled by natural enemies. These consist of predatory Coccinellidae and Chrysopidae, and by hymenopterous parasitoids, especially of the family Braconidae, which in England seems to be the most important.


Schmidt, M.H., Lauer, A., Purtauf, T., Thies, C., Schaefer, M. and Tscharntke, T. 2003. Relative importance of predators and parasitoids for cereal aphid control. Proceedings Royal Society London (B). 270: 1905-1909.

Giller, P.S., Ryan, B., Kennedy, T. and Connery, J. 1995. Aphid-parasitoid interactions in a winter cereal crop: field trials involving insecticide application. Journal of Applied Entomology 119: 233-239.

Jabraeil, R,, Shirzad, R., Bahram, N., Gadir, N.G. and Hooshang, R.D. 2011. Resistance and susceptibility of various wheat varieties to Sitobion avenae (Hemiptera: Aphididae) in Iran. Applied Entomology and Zoology 46: 455–461.

Olmez, S. and Ulusoy, M.R. 2003. A Survey of aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) in Diyarbaklr, Turkey. Phytoparasitica 31: 524-528.

0zder, N. 2002. Development and fecundity of Sitobion avenae on some wheat cultivars under laboratory conditions. Phytoparasitica 30: 434-436.

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