Location: Subtropical Horticulture Research
2016 Annual Report
Objectives
1. Identify semiochemicals that mediate the behavior and physiology of exotic insects such as tephritid (Ceratitis and Anastrepha) and drosophilid (Zaprionus indianus) fruit flies, the redbay ambrosia beetle, the cocoa pod borer, and other new invasive pests from the Caribbean and Central and South America.
1.A. Determine and document behavioral and olfactory responses to semiochemicals that have potential use in monitoring and control systems.
1.B. Identify and quantify insect semiochemicals; develop improved systems to collect and identify semiochemicals.
2. Develop semiochemical- and/or chemical-based technologies that lead to products for detection, behavioral disruption, or surveillance of insect pests that threaten food security.
2.A. Develop synthetic and natural product lures based on host location and/or feeding cues that are formulated for effective use in integrated pest management.
2.B. Develop optimized trapping and control systems based on chemical lures in combination with traps and bait stations.
3. Develop practical systems for integrated pest management using
semiochemical and other detection-based technologies to reduce the threat of importation and establishment of exotic pests from foreign tropical and subtropical environments by suppressing and/or controlling the population at the source.
3.A. Develop IPM tools for tephritid fruit flies using semiochemical-based technologies for use by regulatory agencies and growers; develop new approaches including improved protocols and spatial analysis techniques to assess monitoring approaches and control systems such as attract-and-kill technologies
3.B. To complement traditional breeding programs for plants resistant to R. lauricola, identify RAB resistant varieties that are low in RAB attractants and integrate quantitative semiochemical phenotype with genotype for marker-assisted selection of pest resistant plants to complement traditional breeding programs.
Approach
Research will consist of field and laboratory experiments to determine the behavior, physiology and chemical ecology of insect pests that can be used in the development of control techniques. Strategies will include the developing new detection and delimitation tools, baits and discrete attract-and-kill devices; identifying pest resistant plant varieties that are low in insect attractant chemicals; and discovering components in the insect's biology that can be exploited for formation of control measures for exotic insect pests that affect plant production.
Progress Report
Susceptibility of Mexican Lauraceae to attack by Redbay ambrosia beetle (RAB). All known hosts of RAB in the U.S. are trees in the family Lauraceae. Since its introduction into Georgia in 2002, RAB has invaded 8 additional states in the southeast, including recent establishments in Texas and Arkansas. As its range continues to expand, RAB will most likely enter into Mexico, a country rich in species of Lauraceae. As part of an ongoing collaboration with the Instituto de Ecología (Veracruz, Mexico), native Mexican laurels are being evaluated for susceptibility to RAB attack. In addition, Hass avocado – the major cultivar grown in Mexico as well as California – is being assessed for risk of RAB attack. Field tests and laboratory bioassays have been conducted in Florida to determine relative attraction and boring preferences of RAB for these potential new hosts. Identification of new attractants for pest ambrosia beetles. Analysis of volatile emissions from wood samples is underway to identify chemical constituents in common with U.S. laurels. This information will be used to prepare a risk assessment for the Lauraceae of Mexico (8 natives and Hass avocado) and to identify potential new attractants to incorporate into lures for improved RAB detection.
Redbay ambrosia beetle (RAB) and laurel wilt are currently established in 9 southeastern states, which has resulted in severe mortality of native Persea species, including redbay (P. borbonia), swampbay (P. palustris), and silkbay (P. humilis). Laurel wilt now impacts production of avocado (P. americana) in south Florida, but in contrast to the situation in forests, RAB is detected at very low levels in affected groves. There is evidence that avocado is a poor reproductive host for RAB and that other ambrosia beetles may transmit the laurel wilt pathogen. To better understand the beetle communities in different ecosystems with laurel wilt, parallel field tests were conducted in an avocado grove (Miami-Dade Co., Florida) and a swampbay forest (Highlands Co., Florida). Tests included ethanol lures (the best general attractant for ambrosia beetles) and essential oil lures (the best attractants for RAB). Data is being collected to compare the diversity of beetles captured at the two sites, and to document the beetle species which can reproduce successfully on the two hosts. This research relates to the development of methods to suppress and control pest populations. This information will aid in our understanding of the complex host-vector-pathogen interactions underlying the epidemiology of laurel wilt disease, and assist in development of IPM programs for the disease vector(s).
Recent ARS research (see FY 15 accomplishments) led to development of an essential oil lure containing 50% a-copaene. In field trials, this lure was found to be more attractive to Redbay ambrosia beetle (RAB) than a commercial cubeb oil lure and a prototype copaiba oil lure, both produced by Synergy Semiochemicals Corp. (British Columbia, Canada). Further evaluations have been conducted to compare efficacy and longevity of the 50% copaene lure to other commercially available RAB lures. Lures containing manuka oil, cubeb oil, and copaiba oil were obtained from ChemTica USA (Durant, OK) and deployed in a field test with copaene and cubeb lures obtained from Synergy. In a separate field test, copaene and cubeb lures were compared to lures containing eucalyptol (a monoterpene recently reported as a new RAB attractant). Data collection is in progress from field tests, and chemical analyses are being performed to quantify terpenoid emissions from each lure. This research relates to the development of new lures for invasive insects. Results from this research will identify the most effective lure currently available for use by action agencies in detection programs for RAB.
Extracts of host and non-host fruit were screened for antennal response by Caribbean fruit fly females as a precursor to identifying new chemicals that could be fruit-based attractants for this and related pest fruit flies. Extracts that elicit a strong antennal response will be tested alone or in combination with previously identified protein-based attractants in future laboratory and field tests. This research relates to the identification of new attractants for pest fruit flies. Results from this research will be used to develop improved attractants needed for this pest.
Attract-and-kill bait stations developed by ARS scientists were tested in Honduras. Field tests were conducted in mango that compared effectiveness of wax matrix bait stations for suppressing populations of the West Indian fruit fly in comparison with untreated controls and bait spray application. This research relates to the development of methods to suppress and control pest populations. Results from this research will be used to determine effectiveness of this population suppression approach for this fly which is not present currently in the U.S. but threatens to invade the U.S. from populations present in the Caribbean and Central America.
Field tests were conducted by collaborators in cacao orchards in Indonesia to compare capture of cocoa pod borer in traps baited with essential oils and extracts of host fruit. Chemical analysis of these materials are ongoing by ARS scientists at SHRS to identify attractants chemicals. A library of chemicals emitted from these plant-based materials is being developed, which will facilitate component identification and quantification. This research relates to the development of attractant-based traps for pest insects.
Accomplishments
1. Identification of a-copaene as a new attractant for the shot hole borer. While conducting research on attractants for RAB in avocado groves, ARS scientists in Miami, Florida, discovered that a-copaene is also an attractant for shot hole borer (SHB), Euwallacea nr. fornicatus. This ambrosia beetle vectors Fusarium dieback, a serious disease currently impacting the avocado industry in California. SHB was first detected in Florida groves in 2012, at low numbers and with little economic impact; however, SHB numbers are increasing in Florida, accompanied by tree damage comparable to that in California. Research by ARS scientists indicates that a-copaene is equal in attraction to the current SHB lure (quercivorol), but a combination of the two chemicals is synergistic, resulting in significantly higher beetle captures. Ongoing research will further evaluate efficacy and longevity of this new 2-component lure for SHB. In collaboration with the University of Florida and Florida avocado growers, the new lure is also being used to survey the avocado production area of Miami-Dade County to determine the prevalence of this new pest.
Research on improved attractants for redbay ambrosia beetle and the Florida shot hole borer (small farm avocado growers).
Research on bait stations for tephritid fruit flies (small farm guava growers).
Review Publications
Brar, G.S., J.L. Capinera, P.E. Kendra, J.A Smith, J.E. Pena, 2015. Temperature-dependent development of Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae). Florida Entomologist. 98(3):856-864.
Pena, J., Mclean, S., Cave, R., Duncan, R., Krauth, S., Kendra, P.E. 2015. Predators and parasitoids associated with Scolytinae in Persea spp., and other Lauraceae in Florida and Taiwan. Florida Entomologist. 98 (3):903-910.
Hughes, M., Smith, J., Ploetz, R., Kendra, P.E., Mayfield, B., Hanula, J., Hulcr, J., Stelinski, L., Cameron, S., Riggins, J., Carrillo, D., Rabaglia, R., Eickwort, J., Pernas, T. 2015. Recovery plan for laurel wilt on redbay and other forest species caused by Raffaelea lauricola and disseminated by Xyleborus glabratus. Plant Health Progress. 16(4):173-210.
Bateman, C., Kendra, P.E., Rabaglia, R., Hulcr, J. 2015. Fungal symbionts in three exotic ambrosia beetles, Xylosandrus amputatus, Xyleborinus andrewesi, and Dryoxylon onoharaense (Coleoptera: Curculionidae: Scolytinae: Xyleborini) in Florida. Symbiosis. Vol 66: pgs-141-148.
Kendra, P. E., W. S. Montgomery, M. A. Deyrup, and D. Wakarchuk. 2016. Improved lure for redbay ambrosia beetle developed by enrichment of a-copaene content. Journal of Pest Science.89(2):427-438
Johnson, A. J., P. E. Kendra, J. Skelton, and J. Hulcr. 2016. Species diversity, phenology, and temporal flight patterns of Hypothenemus pygmy borers (Coleoptera: Curculionidae: Scolytinae) in South Florida. Environ. Entomol. 45 (3): 627-632.
Shelly, T., Epsky, N.D. 2015. Exposure to tea tree oil enhances the mating success of male Mediterranean fruit flies (Diptera: Tephritidae). Florida Entomologist.
