Insektbejdsning med supplerende insekticidsprøjtning

Conclusion

In a field trial with a low attack of pygmy beetles (Atomaria linearis), a yield increase of 7 percent was obtained for seed treatment with Gaucho WS 70 (60 g imidacloprid) and 3 percent for seed treatments with Force 20 CS (10 g tefluthrin), but with no clear difference. In a field trial with low attack of thrips, 0-2 percent yield increase is obtained for seed treatments, however, the yield increase is not significant. Of the two insecticide seed treatments, Gaucho WS 70 has the best effect against both pests. In the two trials, no clear additional yields have been obtained for supplementary foliar spraying with the pyrethroids Lamdex and Mavrik.
On average of 6 trials in 2019-2021 with attacks of pygmy beetles and thrips, seed treatment with Gaucho WS 70 and Force 20 SC have resulted in yield increases of 13 and 11 percent with no statistical difference but statistical difference to untreated. Supplementary sprays have not increased the sugar yield.
In the trials 2020, weak infestations of Myzus persicae did not result in virus yellows. In 2018, in field trials with infestations of black bean aphids (Aphis fabae), seed treatment with Gaucho WS 70 resulted in 12 per cent yield increase and Force 20 CS resulted in 2 percent yield increase, as Force has no effect on prayer aphids.