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Small American raspberry aphidOn this page: Identification & Distribution Other aphids on the same host Damage & Control
Identification & Distribution
Adult apterae of Aphis rubicola (see first three pictures below) are very small, yellowish to green aphids, with mainly pale appendages. The spring form has 6-segmented antennae, but the summer dwarfs have 5-segmented antennae (cf. Aphis rubifolii, which always have 5-segmented antennae). The antennal terminal process is 2.0-2.6 times as long as the base of antennal segment VI. The apical rostral segment (RIV+V) usually has 3-4 accessory hairs. The prothorax and abdominal tergites I & VII usually have marginal tubercles. The dorsal body hairs are mostly very long, the longest being 2.5-4.0 times the basal diameter of antennal segment III (cf. Aphis rubifolii, which has much shorter body hairs). The siphunculi taper from base to flange and are pale or dusky, and sometimes dark at their apices. Abdominal tergite VIII has 3-5 hairs, and the cauda usually has 10-12 hairs. The body length of the Aphis rubicola spring form is 0.9-1.2 mm, with summer dwarfs only 0.6-0.9 mm in length.
Alatae of Aphis rubicola (see second picture below of preserved specimen) have the head and thorax shining black with dark marginal sclerites on the abdomen. They have 3-10 rather large secondary rhinaria on antennal segment III in a single row.
Aphis rubicola feeds on the new growth leaves and shoot apices of American red raspberry (Rubus strigosus) and black raspberry (Rubus occidentalis). In summer they are found on the fruiting canes. There is no host alternation. Sexuales (with apterous males) develop in autumn. It is widely distributed through North America.
Other aphids on the same host
Aphis rubicola has been recorded on 2 Rubus spp. (Rubus occidentalis, Rubus strigosus).
Damage and control
Aphis rubicola is a vector of raspberry leaf curl virus, which causes a serious and eventually fatal disease of raspberry plants. The leaves arch stiffly or curve downwards, turning yellow in red raspberries and very dark green in black raspberries. As the disease progresses, the canes may stiffen and become brittle and fruits become small, seedy and crumbly. The plant may be killed in two or three years.
The best way to control the disease is to remove infected plants, and reduce aphid populations using a strong jet of water from the garden hose, or with insecticidal soap (see How to prevent Raspberry Leaf Curl Disease).