Combination of the entomopathogenic nematode Heterorhabditis bacteriophora and the nematode-trapping fungi Dactylaria brochopaga and Arthrobotrys conoides for controlling Meloidogyne incognita in tomato fields

Abstract

Effects of combining an entomopathogenic nematode (EPNs) and nematode-trapping fungi to control root-knot nematode were studied in the laboratory and in a tomato field. Bioassay effects of EPNs (Heterorhabditis bacteriophora) on growth of the two nematode-trapping fungi (Dactylaria brochopaga and Arthrobotrys conoides) attacking J2 of Meloidogyne incognita were studied in the laboratory. A field experiment was conducted in a tomato field. The mortality percentages were higher in combining EPNs and trapping fungi than either by trapping fungi or EPNs alone. Combining EPNs with A. comcaides fungi caused mortality higher than application by EPNs and trapping fungi D. brochopaga. The highest mortality percentage of combined EPNs and trapping fungi on larvae, root galls and egg-masses of M. incognita in tomato field were in the treatment of combined EPNs and D. brochopaga several times and the treatment of combined EPNs and A. comcaides several times, followed by the treatment of combined EPNs and D. brochopaga one time, and treatment of combined EPNs and A. comcaides one time. In the third stage came the treatment of D. brochopaga alone, and the treatment of A. comcaides alone, finally came effects of the treatment of EPNs alone. The highest tomato yield was recorded in treatments of combined EPNs and D. brochopaga or A. comcaides compared to the separate treatments and control. Thus, we recommend farmers to use combination of EPNs and trapping fungi for increasing the mortality of M. incognita in tomato fields.