Microbial ecology of nematodes for sustainable crop protection in Ghana

Overview

This research initiative investigates the ecology of soil microbes associated with plant-parasitic nematodes in tomato-producing regions of Ghana, with the goal of advancing biological crop protection. Plant-parasitic nematodes are devastating pests that invade crop roots and complete their life cycle underground, causing significant yield losses. Soil microbes, including bacteria and fungi, can attach to the nematode cuticle and antagonize the pest directly or activate host plant defenses. Understanding the microbial communities that colonize nematode surfaces and the surrounding rhizosphere can reveal natural suppressiveness mechanisms that protect crops without relying on chemical pesticides.

The project targets four major tomato-producing regions in Ghana: Ada, Berekum, Pwalugu, and Ziope. By characterizing the microbial composition across these distinct agroecological zones, the research aims to identify candidate microorganisms with potential as biocontrol agents for integrated pest management.

Technical specifications

Research approach:

• Soil sampling and microbial isolation from rhizospheres across four major tomato-producing regions in Ghana
• Preliminary laboratory analysis has already identified Gram-positive and Gram-negative bacteria, along with fungal species including Fusarium, Trichoderma, and Aspergillus
• High-throughput amplicon sequencing targeting bacterial 16S rRNA ribosomal gene and fungal ITS genes for comprehensive community profiling
• Bioinformatics pipeline including sequence demultiplexing, OTU clustering, dereplication, and singleton removal
• Phylogenetic tree construction using UniFrac methods
• Multivariate statistical analysis on OTU abundance tables, with individual PCA plots generated from 16S rRNA and ITS profiles

Key scientific rationale:

• Soil suppressiveness arises from the inability of pathogens to survive and establish, or their inability to cause disease at significant levels in certain soils
• Nematodes diversify and adapt within habitats under competitive conditions, resulting in coexistence of microbial populations
• Microbial attachment to nematode surfaces can antagonize pests directly or trigger plant immune responses

Technology readiness level

This research is at an early discovery stage (TRL 2–3). Preliminary soil analyses have been completed, confirming the presence of diverse bacterial and fungal taxa in tomato fields. The next phase involves expanded geographic sampling and high-throughput sequencing across four regions. The outputs will be microbial community profiles and candidate biocontrol organisms, which will require further validation through greenhouse and field trials before commercial development. The University of Ghana offers a strong foundation for this work through its applied research mission and dedicated technology transfer and IP unit supporting protection, licensing, and industry collaboration.