A second fungicide spray could be a worthwhile investment on late-lifted sugar beet this season, according to Syngenta.
Many crops still look pale and yellow after the wet summer, so it will be more important than ever to prolong leaf retention and keep disease out to make the most of late summer growing conditions, the firm’s Simon Parker said.
Sugar beet can put on yield until November and leaving healthy crops in the ground until just before they are delivered could also help minimise storage and clamping losses, he said.
Independent trials by East Anglian agronomist Simon Fisher found good results from two applications of Spyrale (difenoconazole + fenpropidin) last year, under high rust pressure. Crops treated with two sprays yielded 79t/ha, which was 20% higher than the untreated and 10% higher than those that received a single spray.
Mr Fisher said the infection sources of all the main sugar beet diseases were present this year and would increase if conditions were right.
“Many crops suffered an early attack of rust, with powdery mildew now expected to increase in dry conditions. We are also seeing more pockets of Cercospora this season, along with Ramularia present at low levels,” he noted.