EVALUATION DE LEFFICACITE DES FOURMIS OECOPHYLLES (OECOPHYLLA LONGINODA) DANS LA LUTTE CONTRE LES MOUCHES DES FRUITS DANS LES VERGERS MANGUIERS DU NORD DE LA COTE DIVOIRE

In Cote dIvoire, with national production of around 180,000 tonnes, mango is the 2nd most important export fruit after bananas. The country is also the 3rd largest exporter of mango to the European market, with 33,000 t, after Brazil (100,000 t) and Peru (80,000 t). However, mango production is threatened by attacks from insect pests, of which fruit flies are the most damaging. The aim of this work is to help reduce the fruit fly population by using weaver ants as a biological control agent in mango orchards. Accordingly, a one-hectare area was delimited into two treatments, i.e. 24 trees per treatment at 3 different sites. The 1st treatment consisted of trees colonized by weaver ants, and the second treatment of trees not colonized by ants. In each treatment, a sample of 100 mangoes was collected, weighed and incubated in the laboratory in muslin-covered basins containing sterile sand. Two weeks later, the mangoes were washed and the number of pupae per kilogram of fruit per treatment was determined. The results showed that the number of pupae was lower in plots colonized by ants (4.24 ± 1.78 pupae/Kg of mango) than in plots not colonized by ants (51.30 ± 22.91 pupae/Kg of mango). In conclusion, weaver ants contribute to the reduction of fruit fly populations in mango orchards.