Entomopathogenic Bacteria, Xenorhabdus: An Alternative Biocontrol Agent for Integrated Management of Root-knot Nematode on Grapevine

Entomopathogenic bacterium, Xenorhabdus has a mutualistic relationship with entomopathogenic nematode of the genus Steinernema and produces several bio-agent compounds with antimicrobial and nematicidal activities. Root-knot nematodes are considered one of the most important pests facing the cultivation of grapevine worldwide. A micro-plot field trial was conducted in naturally infested soil with Meloidogyne incognita to evaluate the potential of two strains of entomopathogenic bacteria namely Xenorhabdus budapestensis DSM 16342 (EMA) and X. szentirmaii DSM 16338 (EMC) applied separately or integrated with neem cake and/or furadan at half of recommended dose on nematode development and growth improvement of Taify grapevine. Data of nematode populations, number of galls and egg-masses, eggs/g root, plant lengths and weights and number of leaves were recorded four months after application. Results appeared significant differences between treatments and control. The triple application was more effective than dual and single applications in reducing nematode infestation and improving plant growth. Combined application of EMC or EMA with furadan or neem cake increased the efficacy (64.6-68.6%) and improved plant fresh weight (27.4-69.5%). Conclusively, utilization of such bacterial filtrates with either neem cake and/or nematicide could gain a successful approach in integrated nematode management programs.