Additional Tests on the Efficacy of Ginger Root Oil in Enhancing the Mating Competitiveness of Sterile Males of the Mediterranean Fruit Fly, Ceratitis capitata (Diptera: Tephritidae)

Abstract

Recent studies have shown that exposure to the aroma of ginger root oil (Zingiber officinale Roscoe; termed GRO hereafter) increases the mating competitiveness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). This result suggests that pre-release exposure of sterile males to GRO might increase the effectiveness of the Sterile Insect Technique (SIT) against this important agricultural pest. Here, we present the results of two experiments that further investigate the utility of GRO in medfly SIT. In the first, we compare the effectiveness of GRO obtained from three different suppliers in enhancing the mating success of sterile males relative to wild-like males in competition for wild-like females. Following adult exposure to GRO in large, holding boxes, we found significant variation in the mating success of sterile males exposed to GRO from different sources. However, regardless of the source, GRO-exposed males obtained significantly more matings than control, non-exposed males. In the second experiment, we found that the introduction of GRO (using two different doses) to closed, paper buckets at the time of pupal placement resulted in increased mating success of subsequently emerged sterile males. The use of GRO in SIT programs is discussed in light of these findings.