Ghana’s rice farmers are losing as much as 84 per cent of their harvests to invasive weeds, researchers have revealed at a stakeholder workshop held here yesterday.

The findings, presented by the CSIR–Crops Research Institute (CSIR-CRI) and the Korea Partnership for Innovation of Agriculture (KOPIA), highlight a growing threat to food security and the urgent need for coordinated national action.

The workshop, attended by more than 50 farmers, extension officers and officials, marked the end of the first year of the three-year KOPIA Rice Weed Management Project.

Scientists identified five major weed species including Echinochloa spp. (“Ashaiman killer”), Leptochloa chinensis (“Black Jerry”), Urochloa humidicola (“Aguda”), Ischaemum rugosum (“Ogo”) and Cyperus spp. (“Atadwe”) as being deeply entrenched in rice fields.

They said the weeds can reduce yields by 50 to 80 per cent while also harbouring destructive rice diseases.

The Project Coordinator at CSIR-CRI, Dr Stephen Arthur, warned that farmers were spending between GH¢1,600 and GH¢2,000 per acre on hand-weeding, describing the cost as “unsustainable”.

He urged farmers to adopt integrated weed management practices that combine timely herbicide application with improved agronomic methods.

Other experts also raised concerns about the broader implications of weed infestation.

 A plant pathologist, Dr Atta Aidoo, linked weed presence to increased cases of rice blast, sheath blight and brown spot diseases, while entomologist Dr Kofi Frimpong-Anin highlighted changes in pest dynamics.

An agronomist, Mr Kofi Lelabi Kota, examined crop–weed competition and the economic implications of current control methods.

Senior officials of the CSIR called for stronger government support for the sector. The Deputy Director-General of CSIR, Prof. Marian Dorcas Quain, stressed the need to support local seed production to reduce dependence on risky imports.

The Director of CSIR-CRI, Prof. Maxwell Darko Asante, urged the National Food Buffer Stock Company to purchase seeds from Dawhenya to consolidate gains made in the sector.

The Director of the KOPIA Ghana Centre, Dr Young Jin Kim, highlighted Korea’s experience in building resilient rice systems and reaffirmed continued partnership with Ghana.

Following the presentations, participants toured demonstration fields to observe the differences between managed and unmanaged plots. Farmers expressed readiness to adopt the recommended practices in the next farming season.

“What we have seen and heard is exactly what we needed,” lead farmer Richard Affleh said.

The KOPIA Rice Weed Management Project will continue monitoring and documenting farmer practices over the next two years, with the aim of developing sustainable solutions to protect Ghana’s rice sector from the growing threat of weeds.