Unusually high numbers of aster leafhoppers (ALs) numbers have been reported from North Dakota in its wheat crop, the June 7 provincial potato bulletin says. High numbers have also been noticed in wheat fields in southern and central Manitoba similar to 2007.
The insects are potential vectors of aster yellows disease which can affect many crops, including wheat, canola and vegetable crops such as carrots and lettuce. They can also cause purple top disease in potatoes.
Samples are being sent for testing for presence of aster yellows phytoplasma. The leafhoppers acquire the pathogen after feeding on an infected plant. The phytoplasma needs a two-week incubation within the leafhopper, before the leafhopper can vector the pathogen.
The bulletin also notes that aster leafhoppers appear very similar to potato leafhoppers. Survey for potato leafhoppers has not been initiated. Producers are advised to monitor their crops for signs of feeding damage or disease.
