Biological control of root-knot nematode in tomato using Trichoderma and Pseudomonas

Abstract:

Root-knot nematode, Meloidogyne incognita, is defined as one of the most economically damaging soil-borne pathogens of tomato worldwide, capable of reducing yields by 30–60% in heavily infested fields ^[1]. This research evaluated the biocontrol potential of Trichoderma harzianum (soil application at 5 kg ha⁻¹), Pseudomonas fluorescens (soil application at 5 kg ha⁻¹), their combination (T.h + P.f), and the chemical nematicide carbofuran (1 kg a.i. ha⁻¹) against an untreated inoculated control in tomato (cv. Castle Rock) under pot-house conditions at the Nile Valley Agricultural University, Assiut during summer 2023. A completely randomised design with five treatments and six replications was used. The combined application of T. harzianum and P. fluorescens reduced root-gall index from 4.2 (control) to 1.6 on a 0–5 scale, suppressed nematode egg mass production by 71.4%, and increased fruit yield by 68.3% over the control. This dual-agent treatment matched 83% of the nematode suppression achieved by carbofuran, while being safer for soil biology and human health. These data support the integration of compatible biocontrol agents as a viable alternative to chemical nematicides in tomato production systems.