An Unexpected Aphid in Strawberries
Last week, I examined a patch of strawberries in a garden just outside our lab in Raleigh, NC. I was hoping to find some strawberry aphids (Chaetosiphon fragaefolii) to photograph as part of a project on aphid vector of viruses in strawberries. After a very short search, I was amazed at my luck when I found some aphids with the clubbed hairs that distinguish strawberry aphids from other species that feed on strawberries. However, something was not quit right about these aphids. Instead of having clubbed hairs all over their bodies, they only had them on their heads and the last few segments of their abdomens. With help from Dr. Matt Bertone at the NCSU Plant Disease and Insect Clinic, the mysterious aphids’ identity was revealed to be the closely related Chaetosiphon minor.
An occasional pest of strawberries, Chaetosiphon minor is not a new aphid to the area, or even the country. It has been documented in most of the eastern U.S. and southern Canada since the early 1900’s. It rarely reaches economically damaging levels of infestation, and as a result little has been researched about its natural history. Similar to the strawberry aphid, C. minor feeds on the underside of foliage close to the leaf veins. Like most aphids, it has a non-winged form that reproduces parthenogenetically and more mobile winged forms that reproduce sexually. It is reported to overwinter in the egg stage, at least in northern states.
C. minor has been shown to vector strawberry yellow edge virus, but other Chaetosiphon species, such as the strawberry aphid, are better documented virus vectors. The fact that we have found virus vectors in addition to C. fragaefolii suggests that we may need to take a closer look at aphid diversity in North Carolina strawberries.
For more information about other strawberry infesting aphids and aphid management, see here.