Abstract:
The oriental fruit fly, Bactrocera dorsalis is an economically important pest known to cause
devastating losses to fruits in Sub-Saharan Africa. Several management techniques have been
developed of which plant extracts are inspiring great interest due to their availability, reduced cost
and risk to humans. The objectives of the study were to compare the attractiveness of different
concentrations (5, 3.3 and 2.5% wt/vol) of aqueous leaf extract of Pimenta racemosa with
commercial methyl eugenol (Stop Mating Block) and document the distribution of Pimenta
racemosa in Southern Ghana. A field work involving trapping was conducted in four selected
mango orchards (Prosper, Boko, Ayikuma and Adumanya farms) at the Coastal Savanna ecological
zone for the major mango season. The experimental design for trapping was Complete Randomized
Block Design (RCBD) with five blocks replicated in the four farms. The insects captured were
collected on weekly bases for a period of 14 weeks. A total number of 174,388 organisms were
captured with 171,412 identified as B. dorsalis and 2,976 identified as non-target (other insects and
spiders). The three different concentrations showed no significant differences (P > 0.05) at Boko,
Ayikuma and Adumanya farms but showed significant difference at Prosper farm. No significant
differences were observed in the general performance of the different concentrations. Stop Mating
Block performed better than the different concentrations with a significant margin across the
various farms. Among the locations sampled during the survey studies revealed that Pimenta
racemosa is present at Aburi and Ahyiresu both located at Akwapim South district in the Eastern
Region. Therefore, the results from the studies suggest that aqueous leaf extract of Pimenta
racemosa has the potential to attract field population of Bactrocera dorsalis even at lower
concentrations (5, 3.3 and 2.5% wt/vol). Even though Stop Mating Block performed better than the
extract, it is economically preferable since most farmers in Ghana are small-holder farmers.
