Research Article Received: 2 July 2009 Revised: 27 November 2009 Accepted: 21 December 2009 Published online in Wiley Interscience: 9 February 2010 (www.interscience.wiley.com) DOI 10.1002/ps.1922 Sex attractant for the banana moth, Opogona sacchari Bojer (Lepidoptera: Tineidae): provisional identification and field evaluation Eric B Jang,a Matthew S Siderhurst,b∗ Robert G Hollingsworth,a David N Showalterb and Elisa J Troyerb Abstract BACKGROUND: The banana moth, Opogona sacchari Bojer, is a polyphagous agricultural pest in many tropical areas of the world. The identification of an attractant for male O. sacchari could offer new methods for detection, study and control. RESULTS: A compound extracted from female O. sacchari elicited responses from antennae of male moths. This compound was identified as a 2/3,(Z)13-octadecadienal by gas chromatography-mass spectrometry. An analog, 2/3,(Z)13-octadecadienol, was also detected in some extracts at roughly a 1 : 20 ratio (alcohol : aldehyde) but did not elicit responses from antennae of male moths. Electroantennograms of synthetic candidate dienals found the strongest responses from (Z, Z)-2,13-octadecadienal and (E, Z)-2,13-octadecadienal. In field trials, (E, Z)-2,13-octadecadienal attracted more male O. sacchari than (Z, Z)-2,13- octadecadienal. Attraction was not improved for either of these compounds when the corresponding stereoisomeric alcohol was added at ratios of 1 : 1, 1 : 10 or 1 : 100 (alcohol : aldehyde). Jackson sticky traps containing 250 µgluresof(E, Z)-2,13- octadecadienal caught as many males as did traps holding virgin females. CONCLUSION: (E, Z)-2,13-octadecadienal has been identified as an attractant for O. sacchari malesandcanbeusedasa monitoring lure of populations of this moth. c 2010 Society of Chemical Industry Keywords: Opogona sacchari; banana moth; attractant; octadecadienal 1INTRODUCTION otherwise desirable horticultural traits. In addition, O. sacchari is The banana moth, Opogonasacchari Bojer (Lepidoptera: Tineidae), responsible for serious damage to coffee trees, caused by stem is an agricultural pest in many tropical areas of the world.1,2 Af- girdling following pruning activities.5 fected crops include banana, coffee, pineapple, papaya, bamboo, In the United States, O. sacchari is federally regulated as a maize, sugarcane, stored tubers and ornamental crops, including quarantine pest.6 Therefore, O. sacchari can be a direct pest and an Dracaena, Cordyline, Chamaedorea palms, Philodendron and Cy- indirect pest on horticultural commodities exported from Hawaii, cas revolute.2 Larvae usually feed internally, burrowing within the because of the risk of commodity rejection if larvae are found stem or roots of host plants. This species was originally described by quarantine inspectors. Commodities exported from Hawaii from the Mascarene Islands in the Indian Ocean in 1856. However, to the US mainland that are sometimes found to be infested during the last 30 years, it has been reported from humid tropical with O. sacchari include palms and Dracaena (Hollingsworth 7 and subtropical areas in Africa, Europe and South America.3 In the RG, unpublished data), banana, rambutan, mangoes and sweet United States, O. sacchari is recorded only from Florida and Hawaii, potatoes (Follett P, private communication, 2009). Current and has been in Hawaii since 1990 or before.3 techniques for monitoring banana moth populations require Opogonasacchari isageneralistfeeder,andinfestationstypically sampling for larvae through destructive assessment of the crop. begin on diseased, damaged or dead tissue, or on other organic Identification of a sex pheromone attractant for O. sacchari material associated with the crop or commodity. However, older would provide a non-destructive population-monitoring tool. This larvae can burrow into healthy plant tissues, such as stems of attractant could be used to study the seasonality and distribution Dracaena sp. (Hollingsworth RG, personal observation). There is of banana moths in various host crops, and to facilitate timing evidence that O. sacchari is expanding its host range in Hawaii. During the past 8 years, it has been noted as a root/stem feeder on orchids and coffee seedlings being grown in potting media ∗ Correspondence to: Matthew S Siderhurst, Eastern Mennonite University, 1200 high in organic matter (Hollingsworth RG, personal observation). Park Rd, Harrisonburg, VA 22802, USA. E-mail: [email protected] Extensive damage to pineapple plantings has also been recorded 4 a US Pacific Basin Agricultural Research Center, USDA-ARS, Hilo, HI, USA 454 recently, with such severe damage to some varieties that they are now avoided by the pineapple industry in spite of their b DepartmentofChemistry,EasternMennoniteUniversity,Harrisonburg,VA,USA Pest Manag Sci 2010; 66: 454–460 www.soci.org c 2010 Society of Chemical Industry Attractant for Opogona sacchari www.soci.org ◦ of pesticide applications with peak pest abundance. Additionally, at 10 Cmin−1, with a 1 min start delay with the injector temper- ◦ pheromone-based tools such as pheromone disruption could be ature set at 250 C, using helium as a carrier gas (1.1 mL min−1). used as part of a control program for this pest. The second instrument, located in Virginia, was a Hewlett Packard Early work to investigate a possible pheromone for O. sacchari G1800A GCD system equipped with an HP-5 MS column (30 m × was undertaken by Rotundo and Tremblay8 and Ioneda et al.9,10 0.25 mm ID, 0.25 µm film thickness). The temperature program ◦ ◦ Both groups found that male moths were behaviorally responsive used was 60 to 250 Cat10 Cmin−1,witha1minstartdelaywith ◦ to extracts from calling females. However, neither group identified the injector temperature set at 250 C, using helium as a carrier the active pheromone components. Rotundo and Tremblay8 used gas (1.0 mL min−1). electroantennography (EAG) to assay several compounds known to be pheromone components of other Lepidoptera, and found 2.4 Electroantennography that (Z)-11-hexadecenal (Z11-16:Ald) elicited responses from moth Electroantennographic responses were recorded either with a antennae, but field work described in their paper was never gas chromatograph–electroantennogram coupled system (GC- published.FieldattractionofOpogonaspp.toa99 : 1mixtureof(Z)- EAD) or with an electroantennogram (EAG) set-up only. Male 8-dodecenyl/(E)-8-dodecenylacetateswas,however,notedduring electroantennographic responses to female pheromone gland a study in Malawi with the tortricid Cryptophlebia batrachopa extracts were recorded using an Agilent Technologies 6890 (Meyrick).11 In Florida, traps baited with virgin females were used gas chromatograph coupled to a Syntech electroantennogram to monitor populations of O. sacchari in greenhouses over a detector system (Hilversum, The Netherlands). The GC was 1 year period.2 These results clearly indicate the existence of a equipped with an HP-5 column (30 m × 0.25 mm ID, 0.25 µm female-produced sex pheromone in O. sacchari. film thickness) with helium as carrier gas (2.3 mL min−1)and Although Opogona sp. sex pheromones have not been make-up gas (10 mL min−1), which were combined with a Y-type identified,pheromonesforothertineidmothshavebeenidentified connector. A Graphpack-3D/2 flow splitter (Gerstel GmbH & Co. and utilized for purposes of control.12–19 The majority of the KG, Mulheim¨ an der Ruhr, Germany) was attached to the base of identified pheromones are 2/3,(Z)13-octadecadienyl compounds, the connector, and the effluent was split 1 : 1 between the flame predominantly alcohols, aldehydes and acetates. Although the ionization detector (FID) and the electroantennogram detector ◦ moths attracted to these pheromones belong to different (EAD) via a heated transfer line (250 C). The injector, in splitless ◦ subfamilies within Tineidae, it is reasonable to postulate that mode, and FID were held at 250 and 275 C respectively. The oven ◦ the O. sacchari pheromone is similar in structure. The objective of temperature program began at 80 C for 1 min, and was then ◦ ◦ the present study was to characterize, synthesize and field test sex ramped at 10 Cmin−1 to 240 C and was held for 13 min. Whole pheromone attractants for O. sacchari. moth heads or excised antennae were secured with electrode gel (Spectra 360; Parker Laboratories, Inc., Fairfield, NJ) between the parallel metal paddle electrodes of a Syntech EAG probe antenna 2 MATERIALS AND METHODS holder (5 mm separation between paddles). Humidified air was 2.1 Insects passed over the antennal preparation and acted as a carrier for Insects used in tests were taken from a colony of O. sacchari that effluent from the EAD transfer line. The antennal signal generated had been in continuous laboratory culture since 1999, originally by the EAD was amplified and filtered by a Syntech NL 1200 collected from infested rambutan bark in Kurtistown, Hawaii. The high-impedance amplifier and analyzed with the FID signal using colony is maintained within ventilated plastic containers (mixed- Syntech GC-EAD2000 software. Z11-16:Ald, previously shown to 8 age colony) provisioned with artificial diet on an as-needed basis elicit EAG responses from O. sacchari, was used to test the system. (continuous production cycle). The artificial bean- and wheat- Electroantennograms of single synthetic aldehyde compounds based diet (modified from Follett and Lower20) contained the were recorded using the recording system described above. following proportions of blended ingredients: 468 g cooked great However, these recordings were taken with compounds directly northern beans, 120 g wheat meal, 70 g yeast flakes, 7.0 g ascorbic introduced into the humidified airstream leading to the antennal acid, 4.4 g sodium benzoate, 2.2 g sorbic acid, 40 g agar and preparation. This was accomplished by puffing air through a glass 1400 mL hot water. Pasteur pipet containing the compound of interest on filter paper. All replicates consisted of sequential puffs in the following order: air only (3×, negative control), 1-hexanol (1–6:OH, 3×, positive 2.2 Gland extractions ◦ control), three sequential puffs of each of the test aldehydes, Female moths, 2–3 days old, were frozen at −70 C while air only (3×)and1–6:OH(3×).