Population development of Aphis fabae Scop. and associated predators in sugarbeets with reduced extend of pesticides
1989
Frings, B. (Bonn Univ. (Germany, F.R.). Inst. fuer Pflanzenkrankheiten) | Sengonca, C.
In the present paper the influence of recommended and reduced expense of pesticide use on Aphis fabae and associated predators in sugarbeets was investigated. Recommended use caused high levels of control when compared to the reduced treatment. But after two weeks the number of aphids in both variants were equal to each other. A reduction in the number of aphid predators (Coccinellidae, Chrysophidae and Syrphidae) also was detected. The number of predators decreased in treatment at recommended level. The highest mean number on one plant to be found in the recommended use was 0.6 in the reduced treatment 1.1 and in the control 1.9. There was no significant difference in yield between the recommended and the reduced expense of pesticides
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