An increasing multitude of insect pests and pathogens is targeting indigenous trees of natural forests, agroforestry systems, and exotic trees in planted forests in Africa. This is raising major concerns for a continent already challenged by adaptations to climate change, as it threatens a vital resource for food security of rural communities, economic growth, and ecosystem conservation. The accidental introduction through trade of non‐native species in particular is accelerating, and it adds to the damage to tree‐based landscapes by native pests and diseases. Old‐time and new invaders heavily impact planted forests of exotic eucalypts, pines, and acacias, and are spreading quickly across African regions. But many non‐native pathogens are recently found affecting important indigenous trees.

1. Pests and diseases of trees in Africa:
review of a growing emergency
Ignazio Graziosi1,2,3, Mathias Tembo4, Jean Kuate5, Alice Muchugi6
Contact: ignazio.graziosi@fulbrightmail.org
1Former consultant, World Agroforestry Centre, Nairobi, Kenya
2Entomologist, Polo GGB, Terni, Italy
3Visiting Researcher, University of Kentucky, Department of Entomology, Lexington KY, USA
4Zambia Agriculture Research Institute, Lusaka, Zambia
5Institute of Agricultural Research for Development, Yaoundé, Cameroon
6Genetic Resources Unit, World Agroforestry Centre, Nairobi, Kenya

2. http://www.worldagroforestry.org/
Landscapes Soils Systems Trees
World Agroforestry Centre (ICRAF)

3. ICRAF Tree Program
• Genetic Resources Unit
Conservation of tree
germplasm
Gene banks

4. ICRAF Gene banks
>20,000 accessions of >200 tree species (food, timber, other)
• Seed Banks (Nairobi; Kunming Institute of Botany, China;
Millennium Seed Bank, UK; Svalbard Global Seed Vault)
• Field Gene banks: >12,000 accessions of 68 species in 42 sites in
16 countries (Africa, Latin America, Asia)

5. Field and seed banks: impact from native and non-native pests and diseases

6. • Conservation of tree
germplasm
• Gene banks (field and
seed banks)
Germplasm Health
Tree health lab
Clean
agroforestry
germplasm
Early
detection
and
management
Tree
resistance?

7. • Understanding trends
of natives/non-natives
targeting trees in
Africa
Review of updated information
to build up basic knowledge and databases

8. Thank you
 Ramni Jamnadass
 Karim Dagno
 Simon Mng’omba
 Catherine Dembele
 Alain Tsobeng
 Antoine Kalinganire
 Zakayo Kinyanjui
 Jane Njuguna
 Eston Mutitu
 Lynne Rieske
Kenya Forestry Research Institute (KEFRI); Institut de Recherche Agricole pour le
Developpement (IRAD); Institut d’Économie Rurale (IER); Forestry Research institute of
Malawi (FRIM)