## 2 Results and Discussion
Three symbols in each group mean n = 3 biological replicates. Figure 3: _Cont_. Figure 2: Heat map showing the changes of abundance values normalized to the compounds that are significantly influenced by extraction solvent and the time of insect sampling during mating stage. Three symbols in each group mean n=3 biological replicates. Comparing the HS-SPME, compounds including: 2,3-hexanedione, _o_-dimethylbenzene, nonane, 2,3_A_-trithiapentane, octanal, acetophenone, 2,6-dimethyl-(_E,Z_)-2,4,6-octatriene, 1H-pyrrole-2-carboxylic acid, 2,6,10-trimethyltridecane, dimethyl phthalate; farnesene, (_E_)-\(\gamma\)-bisabolene, 5-phenyl- undecane, carbonic acid 2-ethylhexyl octyl ester, 2-ethylhexyl octyl ester; and 5-dodecyldihydro-2(3_H_)-furanone, were detected from medfly adults during mating stage (Table 3, Figure 4). [PERSON] et al. [7] reported that the compounds acetoin, 2,3-hexanedione, hexaldehyde, 4-hydroxybutanoic acid, 2,3,4- trithiapentane and octanal were identified from medfly adults using HS-SPME. [PERSON] et al. [25] used HS-SPME to identify the pheromones from medfly adults. They found that methyl (_E_)-6-nonenoate and (_E_)-6-nonen-1-ol were the main compounds. [PERSON] et al. [14] studied the volatile compounds emitted by sexually mature male Mediterranean fruit flies. They have been identified the key component involved in the sexual attraction of virgin female flies to males demonstrated to be the novel sex pheromone 3,4-dihydro-2_H_-pyrrole. [PERSON] et al. [26] reported that the male-produced volatiles eliciting responses from female were ethyl (_E_)-3-octenoate, geranyl acetate, (_E_,_E_)-\(\alpha\)-farnesene, linalool, and indole, while [PERSON] et al. [12] found and identified five major component groups that included ethyl hexenoates, hexanoates, methyl octenoates, monoterpenes and ketones. Figure 4: Chromatograms obtained after separation of compounds using DI-SPME and HS-SPME. Figure 3: Red points represent significant compounds from the first solvent (**A**) and from the second solvent (**B**). Green points (**A**) and (**B**) are not significant. Each point represent three biological replicates. Identifications are based on comparisons of both mass spectral data and GC retention indices with those of authentic reference compounds. Several components remain unidentified. Most of the unidentified run components were present at low concentrations, and were therefore thought to be contaminants. Some compounds were presented before mating, but they were missing during the mating stage. Some chemicals, were increased and some decreased within the mating stages (Tables 1 and 2). [PERSON] [27] reported that medfly males are stimulated to more frequent episodes of calling activity, when they are able to detect the presence of other medfly males. However, this interaction to visual and acoustic cues rather than to chemical communication. [PERSON] et al. [25] and [PERSON] et al. [28] studied which components are necessary to trigger an attractive response from female flies. This has been addressed to varying degrees except the present one, which is primarily a qualitative and semi-quantitative examination of the male emission complex. Ongoing laboratory evaluations of the major pheromone components identified indicate that many compounds contribute differentially, but synergistically to the pheromone's attractiveness for the female medflies. Other intermediate to low-concentration components may also be required to attain full parity with calling males. [PERSON] et al. [29]; [PERSON] et al. [30] reported that three different medfly ages (5-6, 11-12, and 20-21 days old), and early-, mid-, and late-morning samples were used to collect volatiles. Thirty-two components were identified. However, propan-2-ol, hexanal, phenol, (\(Z\),\(E\))-\(\alpha\)-farnesene, prop-2-yl-(\(E\))-3-ocenoate, ethyl (\(E\))-2-ocenoate, and propyl (\(E\))-3-ocenoate had been only partially identified in an earlier study.