The document summarizes the West African Fruit Fly Initiative. It finds that losses from fruit flies in Benin's grafted and non-grafted mango orchards in 2006 were over 400,000 Euros. Biological control methods are proposed, including using weaver ant colonies to control fruit fly populations. Studies in Benin show weaver ant abundance on trees reduces damage from fruit flies, with little to no loss where ant abundance is high. The initiative aims to promote weaver ant use in West Africa through workshops, demonstrations, and information materials in local languages.

1. West African Fruit Fly Initiative
Jean-François Vayssières, Antonio Sinzogan,
Jean-Franç Vayssiè
Apollinaire Adandonon, Ousmane Coulibaly, Paul Van
Coulibaly,
Mele (IITA-CIRAD-ARC Cotonou).
(IITA-CIRAD- Cotonou).
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

2.  In 2006, estimated cultivated mango areas were ~ 2 300 ha
(90% grafted (2 070 ha) and 10% non grafted (230 ha)).
 Grafted mango losses in 2006...........................3,4 t/ha
Non grafted mango losses in 2006....................2,2 t/ha
 Total grafted mango losses in 2006 .......................7 038 tonnes
Total non grafted mango losses in 2006.................. 506 tonnes
 Estimated grafted mango losses in 2006......... 422 280 000 FCFA
Estimated non grafted mango losses in 200... 12 650 000 FCFA
TOTAL....434 930 000 FCFA = 663 000 € = ~ 966 000 US$
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

3.  Alien species:
probably originated from
India and Sri Lanka.
 Species highly
polyphagous (targets:
more than 40 species of
fruit crops in Benin).
 Exotic species with
high biotic
potentialities (> than
those of native species).
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

4. November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

5. => Cultural by grafted ealier cv on late cv...
=> Prophylactic by collected damaged fruits…
=> Biological control with weaver ants (generalist
predators).
=> Biological control with micro-wasps (native or exotic
parasitoid species).
=> Biological control with entomopathogens.
=> Integrated Pest Management with GF 120 spot TTT,
other bait sprays, MAT…
=> Post-harvest TTT with hot-water TTT.
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

6. • A similar asian species, Oecophylla smaragdina, has been used
in S.E. Asia by the growers 2000 years ago: this is the oldest
example of biological control.
• The australian growers also are using Oecophylla smaragdina in
their orchads with efficacy (Peng, 2005).
• In Africa, Oecophylla longinoda is a generalist predator of
different types of insectes; a colonies of 12 nests could carry
45 000 preys per year (Dejean, 1991).
• The control of mango fruit fly species in West Africa is not still
really achieved...!!!
• So, it was relevant to launch the study on african W.A. in 2005.
November 24th 2009
CIRAD-IITA-WARDA’ team Jean-François Vayssières et al.. IITA - R4D - Ibadan

7. Ecology and
behaviour of the
African weaver ant
are not well known
and should be
improved under
different
approaches:
 Agro-ecological
 Socio-economic
 Technical.
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

8. • Weaver ant rarely capture fruit fly adults. This
type of predation could be observe after many
observations in the field....
• Weaver ant use to capture fruit fly larvae (L 3)
• KEY POINT : Female of fruit fly avoid laying
eggs by detecting the territories of enemy
ants through mainly chemical cues
(pheromones) left by ants on fruits they have
patrolled on...
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

9. Loss assessment in 2005 (end of April)
Ant abundance Nil low medium High
Nb trees 85 178 77 40
Nb nests/ tree 0 1à4 5à8 >8
Loss due to FF 24.1 ± 1.3a 15.4 ± 0.9b 7.0 ± 0.9c 0.8 ± 0.4d
 Losses caused by fruit flies depend on ant abundance
on the tree. The lower the ant abundance the higher
the damage.
 High abundance of ants on the mango trees reduce
considerably losses caused by fruit flies.
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

10.  In dpt of Borgou (Benin) most of growers have
adopted weaver ants against fruit flies since 2005.
Some of them have introduced Oecophylla colonies…
 In other dpt of Benin, other experiments and F.F.S. are
planned in 2010. Visits in orchards of Borgou where this
control method is working is also planned.
 In other countries of West African Fruit Fly Initiative
workshops, F.F.S., different tests are planned with
growers associations, NARS and extension services...
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

11.  To write new leaflets, and new articles.
 To participate to rural video projections.
 Leaflets will be translated in local languages (Fon,
Dindi, Bariba, Yoruba in Benin, Mossi in Burkina,
Bambara in Mali, Wolof in Senegal, Puular and Soussou
in Guinea, Dioula in Côte d’Ivoire…).
 Available: one leaflet (WAFFI n°= 5) in FV & EV, 4
articles (JEE, IJPM 2, PE), and 1 in R4D on this issue.
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

12.  Very economic; very industrious; self maintain & self
regeneration…
 Save up growers time and labor by being permanent in
the orchards.
 Weaver ant are widespread in all West Africa from St
Louis to Lagos, from sahelian zone to Guinean zone,
even they are more abundant in Guinean and
Soudanian zones.
 Natural enemies free of charge and available
all the time …!
November 24th 2009 Jean-François Vayssières et al.. IITA - R4D - Ibadan

13. West African24th 2009 Initiative
November Fruit Fly Jean-François Vayssières et al.. IITA - R4D - Ibadan