INCREASED spore release from sclerotinia is likely following the change to warmer, drier weather, warns John Davies of ADAS Terrington. If forecast showery weather follows, and petals stick, oilseed crops on or near sites with a history of the disease are at high risk, he says.
In a few cases up to 50% of petals have been found infected already, he says. "Spraying is essential in these crops to prevent yield loss." Carbendazim can reduce stem numbers infected with the disease, but yield increases from iprodione or vinclozolin based products are often greater, he adds.