Archive Article: 1997/10/04
A number of fungicides can be applied for canker control. ADAS trials highlight Punch C (flusilazole + carbendazim) and Plover (difenoconazole) as being more flexible and effective against severe infection. Timing of treatment is, however, probably more crucial than choice of product.
The speed at which infection moves into the stem after initial leaf infection gives the grower seven to10 days at most to catch canker after first leaf spots are seen. There is limited kickback from the products on the market so priority should be given to oilseed rape once symptoms are seen.
Infection can occur from October through to December and even into the New Year so attention should be paid to warnings from advisers, agrochemical companies and distributors. Spraying may not be needed until December but waiting until then – when infection first took place in October – can halve the yield benefit from spraying.