[en] Experiments were conducted from 1994 - 1998 to test the attractiveness of combinations of food-based chemicals for C. capitata (medfly) in Guatemala. Most studies were done in coffee. The 1995 studies, using the FA-2 attractants (ammonium acetate and putrescine) showed that this combination was attractive for females and had potential for use in conjunction with a SIT program. The 1996 studies at three elevations demonstrated that, in general, these attractants, when used in either the Open Bottom Dry Trap (OBDT), Closed Bottom Dry Trap (CBDT), or International Pheromone's McPhail Trap (IPMT) performed better than the Jumbo McPhail trap (JMT) baited with NuLure and borax (NU+B) for capture of feral females. At the high elevation (1400 m), the IPMT with FA-2 and OBDT with FA-2 were best; at the middle elevation (1100 m), the ORDT, IPMT, and CBDT with FA-2 were best; and at low elevations (659 m), the IPMT with FA-2, JMT with NU+B and ORDT with FA-2 were equal in performance. At the middle elevation, using sterile flies, the OBDT with FA-2 worked best. When experiments were carried out in pear, the traps using the FA-2 attractants captured more female flies than the JMT, NU+B, but not significantly more. During the 1997 trials, a third component, trimethylamine was added to the two component lure (FA-3). This attractant was tested in a number of locally produced traps using 2 I soft drink bottles with different color bottoms. The dry versions of the traps contained a yellow sticky insert. All study sites were at low elevation 600 - 650 m, in coffee, testing both sterile and feral flies. With the feral flies during the first phase of the study at finca San Carlos, there were no significant differences between treatments, at finca San Luis, the clear local trap with sticky insert and the green local trap with sticky insert were best, and at finca Valapraiso, the green local trap with yellow sticky insert and yellow local trap with sticky insert captured more flies. During the second phase of the study, only finca Valparaiso reported significant differences. Here the IPMT, FA-3 with sticky insert and the clear local trap with sticky insert worked best. For sterile flies, the Jackson trap with Trimedlure (JT, TML) and a locally made OBDT, FA-3 with yellow sticky insert were best at finca San Carlos, the JT, TML and the yellow local trap with sticky insert were best at finca San Luis and the JT, TML and the green local trap with yellow sticky inset captured most flies at finca Valparaiso. For some unexplained reason, all wet versions of the traps performed poorly. In pear, the Tephri, FA-3, wet performed best, followed by the wet, yellow local traps without and with the yellow sticky insert, respectively. Trials were also conducted to construct egging devices for sterility assessment. Females did lay eggs into various artificial substrates. However, both mated and unmated feral females laid eggs into agar balls, so, unless mating events are recorded, per cent egg hatch and number of eggs produced per female. (author)