August 2, 2012

Aster Yellows Disease infestation affects Canada's wheat yields

An unusually high infestation rate of disease, commonly seen in rapeseed are now impacting wheat and other prairie crops, causing lower wheat yields and quality.

Ieuan Evans, Pathologist and Senior AGRI-TREND^® Agri-Coach^® has confirmed the widespread infection of Aster Yellows in wheat and other crops.

"It is not uncommon to find Aster Yellows in rapeseed most years. However, this year the infection rates in rapeseed are as high 10-40% in many areas." Says Evans, "However, our Agri-Coach professionals began to notice unusual disease symptoms in wheat fields adjacent to infested rapeseed fields together with very high levels of leaf hoppers."

In infested wheat fields the disease has taken the form of yellowish to reddish foliage along with premature dying of randomly scattered wheat plants at anthesis or early milk stage. Areas such as Swan River, MB and the north eastern corner of Saskatchewan have up to 30-40% of bleached or dying heads observed in wheat fields infected with Aster Yellows. The symptoms have also been observed in central and northern Alberta. This will likely result in significant yield loss.

Diseased wheat, barley and rapeseed samples gathered throughout the prairies by Agri-Coach field personnel have been confirmed positive for Aster Yellows in tests performed CFIA approved laboratory Phyto-Diagnostics Ltd run by Peter Ellis. Additional samples are being forwarded to Agriculture Canada personnel for testing.

"It is felt that this year the Aster Yellows infestation occurred as a consequence of unusually high levels of leaf hoppers arriving in prairie Canada from the US in mid-May to early-June. Early spring tests of the leaf hoppers by Manitoba Agriculture confirmed higher than normal levels of phytoplasmal infection. The Agri-Trend field tours continue to reveal very high levels of leaf hoppers and phytoplasmal infections."