Abstract:
The apple clearwing (Synanthedon myopaeformis Bork.) that has been regarded until the 1960-ies in whole Europe as one of the secondary pest of apple trees weakened by other factors; it has become a significant pest and this can be attributed to changes in apple production technology.
Intensive plantations were established, rootstocks with low growing capacity introduced and these may result in the early death of young trees under unfavourable environmental conditions.
In the experimental plot that had received for 8 years IPM measures it was observed that both the number and distribution of clearwing adults trapped in sex-pheromone traps differed significantly from ones of a neighbouring plot that received conventional plant protection, although their past records were identical.
As in the conventiona 1 one the swarming lasted longer than in the IPM plot and the number of trapped adults was significantly higher it was assumed that the differences can be attributed to the effect of some environmentally friendly preparations applied in the IPM orchard.
Based on this hypothesis, from among the environmental preparations used against codling moth, leaf rollers and leaf miners the following were applied after the swarming peak of clearwings in 1992: Dimilin 25 WP (diflubenzuron), Insegar (phenoxycarb) and Match (lufenuron), in 1994: Dimilin 25 WP, Match, Cascade 5 EC (flufenoxuron) and Dipel (Bt).
The results with Dimilin and especially with Match, Dipel and Cascade are significant, because clearwings fly in high numbers in July and this may coincide with treatments against codling moth, tortricids or leaf miners.
The environmental methods against S. myopaeformis can easily be incorporated into the IPM of apple.
By using suitable forecasting methods the control measures can be connected with treatments against the most important Lepidopterous pests of apple and in a given case they do not even require a distinct treatment only a good choice of preparations.
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