Compatibility of Atheta coriaria with other biological control agents and reduced-risk insecticides used in greenhouse floriculture integrated pest management programs for fungus gnats

• Published in: Canadian entomologist 2006-10, Vol.138 (5), p.712-722
• Main Authors: Jandricic, S., Scott-Dupree, C.D., Broadbent, A.B., Harris, C.R., Murphy, G.
• Format: Article
• Language: English
• Subjects: Acari; Agricultural practices; Atheta coriaria; Biological and medical sciences; Biological control; biological control agents; Bradysia; Coleoptera; Control; Coriaria; Diptera; Entomology; entomopathogenic nematodes; Flowers & plants; Fundamental and applied biological sciences. Psychology; fungus gnats; Greenhouses; Insect control; insect growth regulators; Insecticides; Insects; Integrated pest control; Integrated pest management; intraguild predation; Laelapidae; Mesostigmata; Nematoda; nontarget organisms; Pest control; Phytopathology. Animal pests. Plant and forest protection; predator interactions; predator-prey relationships; predatory insects; predatory mites; prey preference; Protozoa. Invertebrates; Rhabditida; Sciaridae; Staphylinidae; Steinernema feltiae; Steinernematidae; toxicity
• ISSN: 0008-347X; 1918-3240
• DOI: 10.4039/n05-106

Fungus gnats (FG) (Diptera: Sciaridae: Bradysia spp.) are economically important pests of greenhouse flowers. Larvae feed on root tissue and transmit a variety of phytopathogens. Atheta coriaria (Kraatz) (Coleoptera: Staphylinidae) is a new biological control agent (BCA) for FG. To support its successful use by the greenhouse industry, its compatibility with current integrated pest management (IPM) programs used in floriculture was assessed. This included investigations of prey preference, possible detrimental interactions with other soil-dwelling BCAs, and the toxicity to A. coriaria of registered and novel insecticides. Atheta coriaria showed little preference among eggs of different pest species or between pest eggs and eggs of the intraguild predator Hypoaspis aculeifer (Canestrini) (Acari: Mesostigmata: Laelapidae). It preferred FG 1st-instar larvae to larvae and pupae of other soil-dwelling pests. The entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) was compatible with A. coriaria, but H. aculeifer mites fed on A. coriaria larvae. Insect growth regulators with limited contact activity (e.g., diflubenzuron) were compatible with adult A. coriaria and had minimal effects on larvae compared with other insecticides. Atheta coriaria can be incorporated into an IPM program for FG if harsh insecticides are avoided, but interactions with predatory mites, as well as its effectiveness against other greenhouse pests when FG are present, require further investigation. Les sciarides (FG) (Diptera: Sciaridae: Bradysia spp.) sont des ravageurs d'importance économique des fleurs de serre. Les larves se nourrissent de tissus radiculaires et transmettent une variété de pathogènes. Atheta coriaria (Kraatz) (Coleoptera: Staphylinidae) est un nouvel agent de lutte biologique (BCA) contre les FC. Afin de favoriser l'utilisation efficace de cet agent par l'industrie de la culture en serres, nous évaluons sa compatibilité avec les programmes courants de lutte intégrée (IPM) en vigueur en floriculture. Cette évaluation comprend des études de préférence de proies, d'interactions potentiellement nuisibles avec d'autres BCA vivant dans le sol et de toxicité des insecticides enregistrés et nouveaux pour A. coriaria. Atheta coriaria montre peu de préférence pour les oeufs des différentes espèces de ravageurs et ne distingue pas entre les oeufs des ravageurs et ceux du prédateur de même guilde Hypoaspis aculeifer (Canestrini) (Acari: Mesostigm