Quiz

July 6, 2022

QUIZ – Sclerotinia stem rot

The window of application for most fungicides is 20 to 50 per cent flower. This quiz has three questions to test your sclerotinia IQ.

1. With ample moisture, apothecia are germinating and shooting their sclerotinia spores into the air. While we have no known threshold for rainfall required for spores to infect, AAFC plant pathologist Kelly Turkington provides this rough guide to describe the moisture required for infection: Rainfall (at least 5-10mm) more than two days a week and daily minimum relative humidity (RH) over ___ per cent. (Enter a number in the box.)

2. In the Canola Watch podcast called “Fungicide IQ”, Mike Harding describes the art and science of fungicide spray decisions. The idea for this topic came when a friend asked Harding about what?

Front and back facing nozzles

Spraying before flowering

Fungicide half life

Pathogen resistance

3. A canola crop with uneven staging presents a challenge for fungicide timing. Which of the following would be the most accurate agronomy statement for fungicide timing on an uneven crop?

Consider spraying when the earliest plants are at the right stage because early infections usually cause the most yield loss.

Uneven crops are too much of a bother. Just ignore them.

Consider spraying when the latest plants are at full flower as this will provide a curative response for the greatest number of plants.

Uneven crops should be sprayed twice because a single application timing is too hard to judge.