Growers using home saved oilseed rape seed should get samples tested for germination and vigour before sowing, experts have advised.

Extremely hot weather has led to seed dormancy in previous years and could be a problem this season following the recent heat wave, said NK Seeds’ Nigel Padbury.

ADAS’s Richard Weigthtman agreed. “Temperatures consistently above 30C have contributed to oilseed rape seed rapidly drying out and coming off the field at 3% to 4% moisture.

“These low levels are very likely to have halted the seed from fully maturing, and forced it to remain in a dormant state.”

Such seed often shows low vigour and may give patchy germination or remain dormant in the ground for several years before emerging as volunteers in subsequent crops, he said.

“Growers who are planning to farm save winter and spring oilseed rape seed this season should therefore make sure they test it for germination and seed vigour, or buy certified seed,” he advised.