Coconut Sector Development Project. Crop protection mission component of the project from 5/10 to 23/10/2000

It is now possible to advise growers benefiting from replanting plots to monitor them regularly and extract Oryctes adults from their galleries using small harpoons. In the event of severe attacks, this basic action can be stepped up with insecticide treatments. At the same time as applying the usual control methods, an adult trapping trial with the aggregation pheromone: ethyl 4-methyloctanoate, is being conducted. Two types of traps have proved efficient: - a bucket without a lid, with birdlimed bottom and sides. - a bucket with two crossed aluminium sheets (Malaysian model). Daily diffusion of 15 mg of this pheromone seems to be appropriate. Nevertheless, it appears that adult catches in buckets are still not perfect: only 25 to 40% of adults entering a given plot are caught in the traps. The other adults seem to be more attracted by the silhouette of the plants. Termites cause considerable damage in zones where the drought was most severe, such as in a few places in Central Region. Insecticide treatments do not pose any particular problems. Nevertheless, growers should be asked to carefully monitor their plots and report the first signs of any attack symptoms to the Coconut Project Officers. Observations of disease spread have shown that the situation remained fairly stable from 1997 to 2000 in Western Region: roughly 60% of healthy coconut plantings remain, the largest zone being Half Assinie, a strip of coconut plantings that extends beyond the border between Ghana and the Ivory Coast. This zone should therefore be kept as healthy as possible with regular effective monitoring and early intervention: felling of coconut palms showing the first symptoms. However, in Central Region, we found on average that the number of plots infected by the disease rose by 15 to 20%. Lastly, in Volta Region, the disease has totally disappeared. Remember that it recurred in 1995; then in 1997, we noted that its development had become very slow. (Résumé d'auteur)