Abstract

Tomato (Solanum lycopersicum L.) is one of Indonesia’s most important horticultural crops. However, its productivity remains suboptimal, partly because of root-knot nematode (Meloidogyne spp.) infestations. Excessive use of chemical nematicides has raised environmental and ecological concerns, highlighting the need for sustainable alternatives. Combining nematode-trapping fungi (NTFs) with beneficial bacteria such as Pseudomonas fluorescens, which can enhance biocontrol activity through synergistic interactions, is a promising strategy. In this study, we evaluated the biocontrol potential of Arthrobotrys thaumasia and P. fluorescens against M. incognita, through in vitro assays and in vivo trials on tomato plants. The in vivo application consisted of six treatments: M. incognita as a positive control, negative control without M. incognita, a chemical control using carbofuran, biocontrol treatments using A. thaumasia and P. fluorescens, and a combined treatment of A. thaumasia and P. fluorescens. Observations were conducted at 7, 14, and 35 days post-inoculation. Results revealed that A. thaumasia induced the highest nematode mortality rate (87%) after 48 h, followed by P. fluorescens (64%). Compatibility assays revealed no antagonism between the two agents. In vivo results demonstrated that the combined application reduced the number of vermiform nematodes and root-knot formation while promoting tomato plant growth. The combined treatment of A. thaumasia and P. fluorescens reduced root galling by 90%, followed by A. thaumasia (76%), carbofuran (43%), and P. fluorescens (36%) at 35 days after inoculation. These findings suggest that combining A. thaumasia and P. fluorescens provides an effective and environmentally friendly alternative for controlling root-knot nematodes during tomato cultivation.