Compatibility of the entomopathogenic nematode, Steinernema feltiae Filipjev with 17 different pesticides and three plant growth regulators, recommended for drench application in glasshouses, was evaluated. The products tested were two biofungicides, Streptomyces griseoviridis (Mycostop) and Trichoderma harzianum (Rootshield), nine chemical fungicides, iprodione (Chipco 26GT), thiophanate-methyl (Fungo Flo 4.5F), azoxystrobin (Heritage), fludioxonil (Medallion), flutolanil (Prostar), mefenoxam (SudDue Maxx 21.3ME), PCNB (Terraclor 400F), triflumizole (Terraguard), and etridiazole (Terrazole), two bioinsecticides, spinosad (Conserve SC) and Bacillus thuringiensis subsp. israelensis (Gnatrol), three chemical insecticides diflubenzuron (Adept IGR), acephate (Orthene), and fenoxycarb (Precision 25WP), one herbicide, clethodim (Envoy) and three plant growth regulators, ancymidol (ARest), paclobutrazol (Bonzi), and uniconazole-P (Sumagic). Infective juvenile nematodes were exposed to each product at the highest recommended concentration in 24-well plates at 228C. Observations on the viability and infectivity of the nematodes were made at 4, 24, and 72 h after exposure. We found that S. feltiae is compatible with the majority of the tested formulations with no loss in viability and infectivity up to 24 h of exposure. The viability of S. feltiae was more than 80% in all the products even after 72 h of exposure. Three pesticide formulations, Prostar (1%), Gnatrol (9%), and Terrazole (10%) decreased the viability of S. feltiae significantly within 24 h compared to the controls. However, during the 24 to 72 hr incubation period, eight pesticides affected the viability of S. feltiae with Gnatrol and Terrazole causing the highest decrease (17% and 15%, respectively). Only Terrazole decreased the infectivity of S. feltiae to Galleria mellonella larvae compared to the control when tested after 24 h exposure. At 72 hr, Orthene and Terrazole caused significant decrease in the infectivity of S. feltiae (10% and 15%, respectively) and Gnatrol caused a significant increase in the infectivity (11%) compared to the Correspondence to: P. S. Grewal. Permanent address of E.A.B. De Nardo: Brazilian Agricultural Corporation Á/ EMBRAPA MEIO AMBIENTE, Rod. SP.-340, Downloaded by [Colorado College] at 17:47 31 March 2015control. Our results suggest that S. feltiae can be tank-mixed and applied in combination with all the tested formulations, except Terrazole.

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Summary 1.There is growing awareness that biological control carries risks as well as benefits, but there are few data on below-ground effects of inundative insect pathogens. We addressed this issue using entomopathogenic nematodes and the soil nematode community in a turfgrass ecosystem as a model. 2. Application of Heterorhabditis bacteriophora strain GPS11, Heterorhabditis bacteriophora strain HP88 and Heterorhabditis indica strain LN2 significantly reduced the abundance, species richness, diversity and maturity of the nematode community by reducing the number of genera and abundance of plant-parasitic, but not free-living, nematodes. 3. Our results are the first to indicate selective suppression of plant-parasitic nematodes by entomopathogenic nematodes, H . bacteriophora and H. indica , with no adverse effect on free-living nematodes. 4. In contrast to the entomopathogenic nematode treatments, trichlorfon (a commonly used insecticide in turfgrass) reduced the number of genera, abundance and diversity of the nematode community by adversely affecting both plant-parasitic and free-living nematodes. 5. The reduction in abundance and diversity of plant-parasitic nematodes without any adverse effect on free-living nematodes that play a role in nutrient cycling, can be considered as a beneficial non-target effect of entomopathogenic nematodes. The mechanisms causing such an effect need to be elucidated in future studies.

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The rhabditid nematode Phasmarhabditis hermaphrodita is a lethal parasite for slugs that is sold commercially in Europe under the trade name Nemaslug TM . We evaluated the effects of P. hermaphrodita on the earthworm Eisenia fetida (Savigny). Adults of E. fetida were exposed in one-liter glass beakers to P. hermaphrodita at three concentrations (1)/, 10)/ and 50 )/ of the field recommended rate of 3)/10 9 billion nematodes/ha) during a 14-day period in an artificial soil substrate. The average body weight, burrowing behavior, mortality and other clinical signals of the earthworms were recorded at 0, 7, and 14 days after exposure to the treatments. In addition, injured earthworms (posterior ends removed) were exposed to the 10)/ field recommended rate of the commercial formulation. Neither intact nor injured E. fetida showed susceptibility to the slug-parasitic nematode P. hermaphrodita during the 14 days of exposure even at concentrations 10 and 50 times higher than the label dose. However, the worms in the attenuated control (autoclaved formulation) had higher mortality and lost less weight compared to the other treatments. Under the conditions of the test, we conclude that the use of the commercially available strain of P. hermaphrodita is safe to E. fetida.