British wheat is coming under attack from new strains of the fungal disease yellow rust, with farmers warned to keep a close check on crops and to spray fungicides earlier than usual.

Previously resistant wheat varieties, including the Group 1 bread wheat Solstice, are now susceptible to a new race of the fungus, which can devastate yields by 50% if left untreated.

The risks have prompted the Home Grown Cereals Authority (HGCA) to warn farmers to be on the look-out for the disease and to bring forward spraying programmes to manage the problem.

"Yellow rust is becoming more of an issue for growers and has the potential to hammer yields, so it’s important farmers spray with fungicides at the earliest point," said Laura Temple, HGCA technical communications executive.