Assessment of fruit fly (Diptera: Tephritidae) management practices in deciduous fruit growing areas in South Africa

Abstract

Ceratitis capitata (Wiedemann) and Ceratitis rosa Karsch are important fruit fly pests of deciduous fruit in the Western Cape Province, South Africa. The main techniques used for fruit fly control in the Western Cape are the sterile insect technique (SIT) targeting C. capitata and the bait application technique (BAT). We determined the relative success of SIT by comparing adult fly-trap catches and fruit infestation in commercial orchards between three regions under SIT and two regions under BAT in the Western Cape, from 2006 to 2008. Ceratitis capitata was predominant in all regions. In commercial orchards, C. capitata catches peaked towards the end of the fruiting season (March to May) and were low between July and January. During the late season, C. capitata catches were significantly higher in two of the regions under SIT. The sterile to wild male ratio in those regions was found to be mostly <1. SIT is not being properly applied in some regions. SIT should be implemented when the pest population is low. The sterile to wild fly ratios should be increased. Alternatively, BAT should be used to lower the pest population before SIT application. Control methods should be more integrated and applied area-wide.