If ever there was a year for timely applications of fungicides on the Ontario edible bean crop, this year is it. The 2021 growing season is shaping up as an ideal year for white mould development, increasing the importance of at least two timely fungicide passes to protect the crop.
In this episode of the Edible Bean School, Meghan Scott, field marketer with Hensall Co-op, walks an edible bean field with a dense canopy looking for signs of white mould and other disease infection.
The excellent growth conditions and high humidity of this growing season have been ideal for white mould infection, and Scott says a two-pass system begins with targeting first pin-bean timing. If the level of risk and conditions persist, a second pass is required within about 10 days of the first to continue that protection.
When scouting for the disease, look deep in the canopy and pay special attention to the older flowers that have dropped. These are food for the mould and will often show first infection symptoms.
While you’re walking the fields, keep an eye out for anthracnose as well, Scott adds. The disease can cause craters on pods and red veining, and you can spread it through your field as you walk, so be careful.
For best results, keep water volumes up for the fungicide pass — 20 gallons per acre minimum, but even 25 gallons would do a better job, as the goal is to push that product down into the canopy. Scott says a spray deposition agent can be helpful, as well.