Growing demand for red onions is driving a search for new hybrid varieties by breeders to rival market leader Red Baron.
UK red onion production has risen from 35,000 tonnes to 50,000 tonnes in three years.
And Cambridge-based plant science company NIAB said it had doubled the number of varieties sown in field trials in a bid to expand the choice for consumers.
NIAB said fast food outlets and TV cookery programmes - which often use red onions to brighten up salads - are
responsible for the extra interest. Varieties called Red Spark and Red Fort, said to have darker flesh than Red Baron, have been grown along with Red Kite, Red Pearl, Kamal and Romy.
NIAB vegetable consultant Mike Day said: “In the past year the number of new varieties has grown to 10.”