20 February 1998

Warm spell and aphids

RECORD-BREAKING warm weather last week may force a revision of aphid control plans.

Early predictions of only average infestations and low levels of virus yellows on sugar beet are now in doubt.

Low counts of sugar beet aphids earlier this month reflected higher than average frost days in January and early February.

That prompted Alan Dewar, of Brooms Barn, and colleague Rik Werker to issue a bulletin saying an epidemic was unlikely.

But counts late last week suggested surviving aphids were thriving. In the absence of hard frosts this week the next official prediction, due on Mar 1, is likely to indicate a more worrying picture, they say.

"Gaucho provides good protection on beet, so there should be no serious problem for growers adopting sound pest management practices," he adds. "Brassica growers may have more of a problem, however."

Larger numbers of other over-wintered pests are also possible, he warns. "Red spider mite may also be surviving quite well, and might also be a problem."