Manitoba potato crops are in excellent shape, but as potato growth continues, it seems aphid populations are growing as well.

According to the latest potato insect report from Manitoba Agriculture, aphid numbers have nearly doubled over the previous week, in two out of three fields that were checked. This could be due to the swathing that's been happening lately in fields like canola. However, Manitoba Agriculture plant pathologist Vikram Bisht says some aphids are more concerning than others.

"Many of these aphids, fortunately, are poor transmitters of the potato mosaic virus," he says. "There is one type of aphid called green peach aphid. At the moment we have only one find in one field, and that is in the southern part of the province. It is an extremely efficient transmitter of virus."

The latest potato insect report says no green peach aphids have been trapped this week.

Bisht also says there is mostly good moisture for potatoes in Manitoba, with some irrigation, however frost hit some early-emerged fields, setting them back a few days. Weather conditions have also been favourable for diseases like early blight and white mould.

"We are getting so much rain, it helps other diseases which usually would be minor problems," he says. "The plants have settled down, and there is very little air movement within the canopy, and that really favours the white mould disease... But those are extremely minor problems, in most cases, and regular fungicides would control them."

Despite seeing cases of late blight in Alberta, Ontario, and Wisconsin, it hasn't been spotted yet in Manitoba.