|
 Blueberry
aphid (Ericaphis fimbriata) is a
North American species that has invaded Europe and other parts of the world
where blueberries are commercially grown.
It is the main vector of blueberry scorch virus. Blueberry aphids appear similar to other
aphid species, and they are usually found in colonies on new growth, the
undersides of leaves, and near flower and fruit clusters of blueberry
plants. These aphids are 1–2 mm in
length, pear shaped, light yellow to green in color and wingless. A few
winged adults occasionally occur and are blackish in color.
Female aphids can continuously
maintain and expand a population without mating by producing cloned
offspring. In favorable conditions,
winged females and males may be produced for mating and population
distribution. Populations can over
winter either as eggs or sheltered adults.
.
Blueberry Scorch Virus. Aphids feeding on infected
plants and then moving to feed on a new host, effectively injecting the virus
into the plant, transmit this virus. Known hosts of
blueberry scorch virus include high bush blueberry (Vaccinium
corymbosum) and cranberry (Vaccimium
macrocarpon), though cranberry may not show symptoms of
infection that vary largely with virus strains and host type. Some plant varieties may show severe
blossom blight, leaf blight and twig dieback, while others may not show any
symptoms. However, all high bush blueberry
varieties may be susceptible.
Other signs of virus infection can
include red line patterns on leaves, yellowing of leaf margins, leaf
mottling, overall pale color, low number of blossoms, or even a loose twig
appearance. It may take up to two
years after initial infection before symptoms start to develop. Also, symptoms may be confused with
bacterial or fungal diseases, frost injury or nutrition deficiency and
therefore testing is required to definitely identify the virus.
Once a plant becomes infected with
the virus it remains so for life, and severely blighted bushes bare little
fruit. In the years following initial
infection bush stems become scattered and the fruit load is markedly reduced
compared to healthy plants. The productivity of infected plants declines each
year, eventually leading to plant death.
Besides transmitting virus blueberry aphids also impact plants by
secreting honeydew and encouraging fungal growth. Their feeding can deform leaves and reduce plant vigor.
REFERENCES
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& Amanda J. Vance. 2015. Seasonal variation in leaf nutrient
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Strik, Bernadine C.
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Wegener, Lisa A., Z. K.
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