The effect of clothianidin on aphids and virus yellows in sugar beet

In three field trials conducted in 1998, 2000 and 2001, in which six plants per plot were inoculated with virus-infective Myzus persicae, clothianidin, applied to pelleted sugar beet seed at 30, 45, 60 and 90 g a.i./unit gave excellent control of green aphids for up to 10 weeks after sowing, comparable to the standard imidacloprid seed treatment at 90 g a.i./unit. The incidence of beet mild yellowing virus in the first two years and beet yellows virus in the third was also significantly reduced. At rates above 45 g a.i./unit virus yellows incidence was consistently but not significantly less in plots treated with clothianidin than in plots treated with imidacloprid. Sugar yields were significantly higher in all treated plots compared to untreated plots, but there were no significant differences between insecticide treatments. Clothianidin would be a suitable alternative to imidacloprid for aphid and virus yellows control in sugar beet.