Bekæmpelse af bedefluelarver

Forfatter:

Anne Lisbet Hansen, NBR

ID:

470-2025, Anne Lisbet Hansen, NBR

Konklusion:

I to forsøg er 1., 2., og 3. generation af bedefluelarver behandlet. Angrebene har været forholdsvise milde med 54-99 pct. angrebne planter med æg 4-17 æg pr. plante resulterende i 9-18 pct. mineret plantevæv i ubehandlet.  Der er generelt svage tegn på effekt af behandlingerne set på resulterende mineret bladvæv.  Der er ikke opnået sikre forskelle i målt merudbytte mellem behandlingerne og til ubehandlet, selvom der i det ene forsøg ses tendens til lidt merudbytte efter behandling med Lamdex og Carnadine.

Baseres på nyeste erfaringer angives en ny bekæmpelsestærskel til kommende sæson: Bekæmpelse iværksættes på planter, frem til 8-bladstadiet, når antal æg overstiger kvadratet af antal løvblade, og der ses begyndende minering. For eksempel: 4 løvblade → 4 x 4 = 16 æg pr. plante.

Conclusion:

In two sugar beet trials, the 1st, 2nd, and 3rd generations of beet fly larvae (Pegomya spp.) were treated with insecticides. The infestations were relatively mild, with 54–99% of plants affected with eggs, 4–17 eggs per plant, resulting in 9–18% mined leaf tissue in the untreated plots. There are generally weak indications of treatment effects based on the resulting mined leaf tissue. No significant differences in measured yield increase were obtained between the treatments and the untreated control, although one of the trials showed a slight tendency toward higher yield after treatment with Lamdex and Carnadine.

Based on latest and others experiences, a new control threshold is specified for the coming season: Control should be initiated on plants up to the 8‑leaf stage when the number of eggs exceeds the square of the number of true leaves, and initial mining is observed.
For example: 4 true leaves → 4 × 4 = 16 eggs per plant.

Publikationsdato:

21/04/2026