Aster Yellows: effects of phytoplasmas on Aster leafhoppers development and preference
In the Canadian Prairies, Aster Yellows Disease is caused by the AY 16SrI phytoplasma group and primarily transmitted by Aster leafhoppers (Macrosteles quadrilineatus Forbes). This disease can have a high incidence in canola fields (<90%) during outbreak years (2001, 2007, and 2012), and can also affect other crops like cereals. Symptoms will include excessive branching, abnormal development of floral parts, and misshapen seeds, and will differ between plant species. In some cases, plants will be asymptomatic, making it difficult to visually identify infected plants. Furthermore, little is known about the host choice and performance of Aster leafhoppers on field crops and weeds, as populations are introduced by wind currents originating in the US in early spring and summer. Disease dynamics are poorly understood and management choices for controlling leafhopper populations and disease spread are not effective. We are using two-choice and no-choice bioassays to determine the host plant preferences and suitability of Aster leafhopppers. This will lead to a better understanding of what crops could be potentially susceptible to becoming infected with AY and what weeds or perennial plants may act as refuges for the insects and the pathogen.
Soils and Crops Workshop