The guava weevil, Conotrachelus psidii is an aggressive pest of guava (Psidium guajava L.) that causes irreparable damages inside the fruit. The volatile compounds of male and female insects were separately collected by headspace solid-phase microextraction or with dynamic headspace collection on a polymer sorbent, and comparatively analyzed by GC-MS. (1R,2S,6R)-2-Hydroxymethyl-2,6-dimethyl-3-oxabicyclo[4.2.0]octane (papayanol), and (1R,2S,6R)-2,6-dimethyl-3-oxabicyclo[4.2.0]octane-2-carbaldehyde (papayanal) were identified (ratio of 9:1, respectively) as male-specific guava weevil volatiles. Papayanal structure was confirmed by comparison of spectroscopic (EIMS) and chromatographic (retention time) data with those of the synthetic pure compound. The behavioral response of the above-mentioned compounds was studied in a Y-tube olfactometer bioassay, and their role as aggregation pheromone candidate components was suggested in this species.

<div class="WordSection1"><p class="Default"> Volatile organic compounds (VOCs) from guava (<em>Psidium guajava </em>L.) reproductive tissues (flower bud, open flower, petal fall, fruit setting, and fruit growth) were collected <em>in situ </em>during the day by headspace-solid phase microextraction (HS-SPME), and from flower bud and fruit setting by dynamic headspace (DHS). The samples were analyzed by GC-MS to separate and identify VOCs produced by guava, which potentially could attract the guava weevil <em>(Conotrachelus psidii </em>Marshall, Coleoptera: Curculionidae), one of the most important pests of guava plants in Colombia and Brazil. The terpenes <em>β</em>-caryophyllene, limonene, and copaene (tentatively identified) were present in all of the guava reproductive tissues, being the major constituents in flower bud and fruit setting, the two guava stages where <em>C. psidii </em>is commonly found. Additionally, the volatile compounds released by male and female insects were separately collected by HS-SPME, and comparatively analyzed by GC-MS. As result, some of volatile detected in the guava reproductive tissues were also released from insects. The behavioral response of the volatile blends and the above-mentioned compounds was studied in a Y-tube olfactometer bioassay, allowing confirming the presence of host kairomones in the guava reproductive tissues.</p></div>

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