Tuesday, March 31, 2015

Sipha maydis, an aphid pest of grasses, found in Colorado

Sipha maydis, a cereal and grass aphid native to Europe, the Middle East, Asia and parts of Africa, was first found outside of its native range in 2002 when it was discovered in Argentina.  In North America, it has been sighted in California (2007), Florida (2011 and 2012), and Georgia (2012) but the aphids were not on host plants and so couldn't reproduce.  The first confirmed encounter in a host-crop was 2014 in Albuquerque, NM on oats.  This past February, another colony has been found in Mesa county, Colorado. This colony was discovered in winter annual grasses and annual wheatgrass  by Bob Hammon, an enotmologist and extension agent from Colorado State University Tri-River Area Extension.

S. maydis, currently without a common name, feeds primarily on more mature grasses and causes yellowing or chlorosis of the plant leaves.  It is also a vector for barley yellow dwarf virus, a destructive disease of small grain crops.

common wheat (Triticum aestivum) by Howard F. Schwartz, Colorado State University, Bugwood.org

The first colony in Albuquerque: New Invasive Aphid Pest Found in Albuquerque Area
The first colonies in Colorado: Sipha maydis: A Potential Threat to Colorado Wheat Production
High Plains Integrated Pest Management wiki article on Sipha maydis: HPIPM:Sipha maydis