Efficiency on cabbage production and impact of insecticide mixtures on parasitoids of diamondback moth.

Commercial cabbage heads were obtained from plots sprayed with mixtures of deltamethrin 25 CE and abamectin 18 CE, which provided control of the damages caused by the Diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae). Results were similar to those obtained from plots sprayed with the liquid formulation of the biological insecticide Bacillus thuringiensis. Deltamethrin and abamectin produced less than 8% of commercial cabbage, whereas the mixture abamectin + deltamethrin produced more than 42%. There was no commercial production in the untreated plots due to the high population densities of the pest. Insecticides alone or combinations did not cause any measurable impact on the populations of natural enemies Diadegma spp. (Hymenoptera: Ichneumonidae) or Apanteles spp. (Hymenoptera: Braconidae).

Plutella xylostella; Brassica oleracea var. capitata ; Diadegma spp. ; Apanteles spp. ; cabbage; selectivity; chemical control; field test efficiency.