Managing Wheat Curl Mite

 

 

Wheat curl mite is one of the more difficult pests to manage in wheat. This is in part due to the limited options available for preventing populations from infesting a field and rapidly reproducing. Other pests can often be managed through the use of insecticides or miticides. However, due to the wheat curl mite’s small size and tendency to inhabit protected areas of the wheat plant, chemical management is often impractical.

 

Although very high mite populations may result in yield losses of as much as 10%, the main concern regarding this pest is its ability to vector Wheat streak mosaic virus (WSMV). Severe infestations of WSMV could result in 100% yield loss of affected fields when infection takes place in the fall. Wheat streak mosaic virus acquisition occurs when the young (nymph) wheat curl mite feeds on an infected host. Acquisition can take 10 to 30 minutes, but the virus will remain active within the mite for 7 to 9 days. Once ingested, WSMV will remain active while the mite develops, but will not pass from one generation to the next through developing eggs.

 

 

Due to the ineffectiveness of chemical management for the wheat curl mite, the best approach is to prevent the “green bridge” from occurring. The term green bridge refers to volunteer wheat or other grass hosts that may harbor populations of the wheat curl mite prior to the new wheat crop emerging.

 

Wheat curl mites are not able to fly, but their small size allows them to be transported by wind. If populations of the wheat curl mite have been building in alternative hosts, it is much more likely that they will occur in the new crop. Alternative hosts for the wheat curl mite include volunteer wheat, corn, foxtail, millet, sandbur, and several other grass weeds.