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Aphids on berries (Rubus)Species Overview: Aphis ruborum Amphorophora idaei Amphorophora rubi Macrosiphum funestum Sitobion fragariae Species of berry
Aphids on berries
Blackman & Eastop list about 50 species of aphid as feeding on berries worldwide, and provides formal identification keys for aphids on Rubus.
As for the host plants, the genus Rubus has a number of subgenera, the most important of which are the subgenus Rubus (blackberries and dewberries) and subgenus Idaeobatus (raspberries). The subgenus Rubus has literally thousands of 'microspecies' mostly within the Rubus fruticosus (blackberry) aggregate. It is unclear whether the aphid fauna differs between these microspecies, although it is important to distinguish between the main species groups (see below ).
The species below are those we have found most frequently, listed in rough order of abundance.
The bramble aphid does not host alternate. It feeds on blackberry (Rubus fruticosus agg.). In early summer it lives in dense colonies, is ant attended and causes leaf curl. The summer dwarf apterae live singly between the veins. Sexual forms occur in autumn. It is widely distributed through Europe into central Asia.
The large raspberry aphid has a sexual stage in its life cycle and does not host alternate. It feeds on the underside of leaves of raspberry (Rubus idaei).
The large blackberry aphid does not host alternate. It feeds on the underside of leaves of blackberry (Rubus fruticosus agg.) and related Rubus species, but not raspberry (Rubus idaei).
The blackberry aphid does not host alternate but spends its entire life cycle on blackberry (Rubus fruticosus agg.). It lives mostly on the young shoots and leaves. Sexual forms are produced in autumn and the aphid overwinters as eggs on the blackberry stems.
The blackberry - grass aphid host alternates from blackberry (Rubus fruticosus agg.) and occasionally other Rosaceae to Grasses (Poaceae) especially Holcus spp. and some Sedges (Carex spp). The eggs hatch in spring and the young nymphs feed on the breaking buds. Colonies build up and in summer alates migrate to cereals and grasses. A return migration takes place in autumn.
We cover three species of berry. By far the commonest is blackberry or bramble (Rubus fruticosus agg.) which consists of a species complex including hundreds, if not thousands, of species.
Blackberry plants have sprawling, prickly arched stems. The leaves (pictured above first) have three to five leaflets with white or grey hairy underside. Blackberry is now grown commercially in many countries for the fruit (pictured above second), as is the related red-berried raspberry (Rubus idaeus) (not pictured here). The raspberry has upright stems with fine prickles, sometimes with a whitish bloom.
A third clearly discernible species group is the dewberries. The European dewberry (Rubus caesius) (pictured below) is often restricted to coastal plant communities.
It has short weak prickles and leaves which always have three leaflets. The fruits are a blackish-blue and are coated with a thin layer of waxy droplets appearing sky-blue.