A THIRD of UK OSR crop could be at risk from turnip yellows virus and growers are being advised not to ignore the threat it poses. A recent survey had confirms that this huge slice of susceptible UK crops are infected, with severe implications on yields, warned plant breeders, Limagrain UK. Turnips yellows virus (TuYV) is transmitted by aphids and it is believed that 70% of the most common aphid, peach potato aphids (myzus persicae) carry it. Work carried out at Brooms Barn reserach station a decade ago, showed there was a 30% yield penalty where levels of the virus were high and infection occurred early in the crop’s life.