12 May 2000

Raise disease rating standards

DISEASE resistance standards in official cereal trials are too lax, claims a leading breeder who believes risk management should be more to the fore when choosing varieties.

NIABs minimum Recommended List ratings, appropriate when wheat was £120/t, are no longer appropriate with prices only half that, says Nickersons Bill Angus.

"A rating of three represents too high a level of risk for growers at only £60/t. Let us encourage NIAB to go for a minimum of four, with a long-term aim of five."

Mr Angus believes growers have ignored the inherent resistance of varieties which can help cut fungicide bills for too long. Only in the past 18 months or so have disease defences begun to attract significant interest. "Often all they wanted to see in our trials were the varieties with highest yields. With wheat at £120/t you couldnt argue with that. But now the worm has turned.

"At £60/t they need to be reducing the risk of disease as well as the expense of controlling it."

Continued low grain prices mean the argument could eventually be extended to other characteristics such as standing power, he adds. "There would not be a problem so long as the new standards were introduced over a reasonable time to allow breeders to adjust."

Despite recent advances the scope for increasing disease resistance is enormous, Mr Angus believes. "The only one we cant do anything about is take-all."

Cereal producers can no longer afford to grow risky varieties, says Bill Angus, who argues that minimum disease rating standards should be raised.