African Weeds of Rice

Rice is one of the main cereals consumed in Africa and the rate of consumption is steadily increasing. Major concerns for the regional rice sector are that rice production does not keep up with increasing consumption rates and that rice prices on the international market are increasing. Moreover, rice-cropping systems suffer from significant production losses due to weed infestations.

Project Templates

The project will contribute to the productivity of rice-cropping systems in sub-Saharan Africa by creating a science and technology network that will foster appropriate weed management practices among the farming, extension and research community. More specifically, the project will:

  • consolidate the interdisciplinary approach of existing scientific knowledge on weed management by building an ICT knowledge base on weeds of west and east African lowland rice-cropping systems;
  • enhance the exploitation and dissemination of best weed management practices in rice-cropping systems of west and east Africa.

Africa is heavily dependent on the international market for rice, importing around 10 million tonnes annually to meet its ever growing demand. East and west Africa are the main rice-producing sub-regions accounting for 95% of the total rice produced in sub-Saharan Africa (SSA). The rice-cropping systems are rain-fed upland and rain-fed and irrigated lowland. The limited production increase is due to ineffective control of weeds, for which it is imperative that an effective weed control mechanism and its effective adoption result in better productivity and in an increase of net rice production. This in turn will ensure food security in the region.

Integrated weed management is considered one of the most attractive options for crop protection, whereby a suitable choice of compatible measures (cultural, mechanical, biological and chemical) keeps the weed population at manageable levels. To be effective, integrated weed management should build on knowledge of weed biology and ecology. A lack of awareness, timely information and knowledge of the weeds limits the actual implementation of integrated weed management at the farmers’ level. Extension services in SSA play a significant role in disseminating advances in agricultural research among the farming community. Most often these extension services rely upon direct contacts with national agricultural research systems (NARS) or universities to identify weeds and obtain recommendations on control measures. Researchers of NARS are constrained by a lack of means to obtain up-to-date information on problem weeds and suitable best management practices from across the region. Improving information and exchange (through networks) would highly benefit the efficiency of existing extension and research systems serving rice farmers in the region. The project will therefore promote environmentally benign farming practices by consolidating the research outputs on weed identification and management.

Project launch, website preparation, and preparation of the project exchange platform and modalities
A project website will be launched to disseminate project description and scientific information on the weeds of rice: It will provide space for collaborative work between project partners through several tools such as a discussion forum, a mailing list, a document repository and access to the knowledge database of rice weed species. The website will also serve as a platform for communication and information with other stakeholders involved in rice production, weed science or botany. The information provided consists of rice weed identification tools (field guide, plant character based identification software, species description sheets, control methods, weed photo library). A first workshop will be organised to establish species description standards and to present existing information technology (IT) tools used in weed science or in botany (IDAO for photofit identification, Ikona for image recognition systems, Pl@ntNote for knowledge database on botany, etc.). The list of weed species of rice from west and east Africa will be defined during the workshop. A collaborative web space will be set up to ensure the active participation of those weed scientists belonging to national agronomical research centres or universities in Africa who wish to collaborate.

Collection and compilation of existing knowledge resources on rice weeds of west and east Africa from National Agricultural Research Systems (NARS), universities and partners involved in the project
Existing knowledge (e.g. personal expertise, unpublished institutional reports, university theses) on rice weed identification and control for the selected weed species will be gathered in the AFROweeds knowledge database. Field trips to the various countries involved in the project (Kenya, Tanzania, Uganda, Benin, Burkina Faso, Chad, Ghana, Ivory Coast, Mali, Nigeria, Senegal)will allow collection of herbarium samples and pictures. Weed species will also be described according to agronomic and environmental conditions.

Integration of various datasets (botanical, taxonomic data, images, etc.) into the knowledge base (identification and control measures) and implementation of the identification and information platform
All the documents and information related to the weed species (descriptions, photos, drawings and scans) will be prepared and integrated into the knowledge database of the project. These data will be used to produce identification and information tools which are available through the AFROWeeds website. This work will be focused on preparing and formatting the documents, producing descriptive pages on the species (html format), and developing the interactive interface of the identification process.

Dissemination, assessment and improvement of the AFROweeds knowledge base
Local training sessions in the participating countries with agronomists, students and extensionists will be organised. Feedback from these sessions will be collected and analysed in order to improve the design and the content of the identification and information tool. This feedback and improvement process will be an iterative procedure. The final product, i.e. the CD-ROM for weed species identificationand information, will be published and will be released during the final workshop in Benin. Visibility actions and communication around the project (e.g. website, newspapers, television interviews, communications in conferences, scientific papers) will also be undertaken.


  • AFROWeeds website.
  • Functional and comprehensive electronic knowledge base on weeds of African rice-cropping systems.
  • Identification and information tools through the AFROWeeds website.
  • CD-ROM for weed species identification.
  • Field guide for species identification and information.
  • Network of African weed scientists.


  • Improved knowledge sharing among African weed scientists.
  • Improved access to information on weed species and management among a wider group of stakeholders (extension services, National Agricultural Research Systems - NARS, universities) in SSA and other tropical areas.
  • Capitalisation of previously acquired knowledge and data on rice weeds in Africa.
  • Improved efficiency of weed control efforts in rice-cropping systems in Africa.
Grant: AFS/2009/219015
Project duration: 36 months (from 17/10/2009 to 16/10/2012)- CLOSED
EC funding: EUR 622,200.00
Total budget: EUR 732,000.00
Project contact:

Dr. Thomas le Bourgeois
Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD)
Boulevard de la Lironde
TA A-51 / PS2
34398 Montpellier Cedex 5
Tel: +33-4-6761.5910 / 7187
Fax: +33-4-6761.5668
E-mail: thomas.le_bourgeois [at]