SUPPRESSION OF PLANT-PARASITIC NEMATODE POPULATIONS IN TURFGRASS BY APPLICATION OF ENTOMOPATHOGENIC NEMATODES

We studied the influence of entomopathogenic nematodes, Steinernema ca rpocapsae and S. riobravis, on natural populations of plant-parasitic nematodes (PPNs) infesting turfgrass in Georgia and South Carolina. S. riobravis applied at 6x10(9) infective juveniles (IJs)/acre provided up to 95-100% control of the root-knot, Meloidogyne sp., sting, Belono laimus longicaudatus, and ring nematode, Criconemella sp., in Georgia, but S. carpocapsae had no effect. S. riobravis was as effective as th e chemical nematicide, Fenamiphos (Nemacur 10G) at 4 weeks after treat ment and more effective at 8 weeks after treatment. In South Carolina, both S. riobravis and S. carpocapsae applied at 1 x 10(9) IJs/acre pr ovided up to 86-100% control of the root-knot, sting and ring nematode s. Application of 6 x 10(9) IJs/acre increased control by only 4-14% o ver the 1 x 10(9) dosage. Possible causes of differences in efficacy o f S. carpocapsae at the two sites are discussed. It is concluded that S. riobravis may provide effective, predictable and economical control of PPNs in turfgrass.