Biocontrol of Duponcheria fovealis (Lepidoptera: Pyralidae) with soil-dwelling predators in potted plants.
Duponchelia fovealis Zeller (Lepidoptera: Pyralidae) is a widespread pest in Dutch greenhouses. Most damage is recorded from potted plants as kalanchoe, cyclamen and begonia. Caterpillars of this pyralid prefer to live in a moist soil layer were they feed on either plant parts or organic matter. Larvae typically seek shelter within plant parts or in soil. This behaviour hampers contact between pesticides and caterpillars. Growers, therefore would welcome an effective method to prevent damage by D. fovealis. This paper describes the effects of the soil-dwelling mites Hypoaspis miles (Berlese) and Hypoaspis aculeifer (Canestrini) (Acari: Laelapidae) and the beetle Atheta coriaria Kraatz (Coleoptera: Staphilinidae) on eggs and larvae of D. fovealis. Both predatory mites and adults of the staphilinid beetle gave excellent control of eggs of D. fovealis in potting soil with kalanchoe. H. miles was slightly (99 percent control), but significantly, better than H. aculeifer (92 percent control). 50 to 87 percent of the eggs were predated by adult beetles of A. coriaria. These beetles also prey on first larval stages of D. fovealis. 87 percent of the H. miles population was present in the upper soil layer, whereas about half of the population of H. aculeifer preferred to stay deeper than 5 cm in soil. This behaviour might explain the slightly better control of D. fovealis by H. miles, since eggs and first larval stages of D. fovealis are mostly present in the upper soil layer. All predators tested may contribute to an integrated or biological system for controlling D. fovealis in potted plants.
Messelink
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Applied Plant Research, Division Glasshouse Horticulture, PO Box 8, 2670 AA Naaldwijk, The Netherlands.
Van Wensveen
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D000818:Animals; D007814:Larva / Q000469:parasitology; D008925:Mites; D009036:Moths / Q000254:growth & development / Q000469:parasitology*; D010572:Pest Control, Biological / Q000379:methods*; D010935:Plant Diseases / Q000469:parasitology; D010944:Plants / Q000469:parasitology*; D012987:Soil / Q000469:parasitology*
D012987:Soil