Location: Subtropical Horticulture Research
2018 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 fruit flies.
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.
2.C. Develop novel, high-tech solutions for OFF detection and eradication, such as lasers, sonic methods, or nano-technologies. For example, traps could be developed that can automatically identify trapped insects based on wing beat frequency, size, weight, or protein content.
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. An insect toxicologist is needed to identify the modes of actions for different pesticide classes on the OFF, and the physiological mechanisms for pesticide resistance development. This research will lead to improved chemical control strategies and reduce pesticide resistance development.
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. Stereochemistry of selected compounds and structural characteristics may play a highly significant role in efficacy of kairomones needed for pest detection and control. The correlations of active components such as configuration, functional groups and identification of cis-, trans- and chiral isomers can influence on the bioactivity.
3.C. Develop pesticide resistance management for fruit fly control by 1) identifying the modes of actions for different pesticide classes on OFF and 2) determining the physiological mechanisms for pesticide resistance development in Oriental fruit fly and other fruit flies.
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 monitoring and control techniques. Strategies will include developing new detection and delimitation tools that will include baits, discrete attract-and-kill devices for insect pests, next generation technologies such as detectors and robots, and network theory and optimization that will improve detection of the Oriental fruit fly and relatives; identifying pesticide modes of action on and physiological response of Oriental fruit fly and relatives for improved pesticide resistance management; identifying new semiochemicals through investigations of plant essential oils and stereochemistry of plant compounds, and discovering components in the insect's biology that can be exploited for control measures for exotic insect pests that affect plant production.
Progress Report
Estimation of sampling range of field lures for Euwallacea ambrosia beetles. Release-and-recapture experiments were conducted in commercial avocado groves to determine the effective sampling range (attractive distance) of the a-copaene and quercivorol lures, deployed alone and in tandem. In addition, flight mill studies were conducted in collaboration with the University of Florida to determine the flight (dispersal) capacity of newly emerged, host-seeking females. Spatial analysis indicated that wind speed and direction had a significant effect on the number of beetles that dispersed as well as the direction and distance of flight. The average sampling ranges of a-copaene and quercivorol lures were equivalent (30-35 m), but the lure combination resulted in significantly higher recaptures (31.2 ± 3.7%) than the quercivorol (11.2 ± 2.6%) or a-copaene (8.8 ± 1.3%) lures alone. Results indicate that the 2-component lure provides more sensitive pest detection, and monitoring traps should be spaced ~40 m apart to avoid trap interference. In lab flight mill tests, average flight distance (unassisted by wind) was 80.9 ± 18.3 m in a 24 hour period. This research relates to Objective 3A (improved protocols and spatial analysis techniques to assess monitoring approaches) and will benefit action agencies in designing surveillance programs for pest Euwallacea.
Evaluation of piperitone as a repellent for Euwallacea in Florida avocado groves. Incorporation of a repellent in a pest management program for Euwallacea may reduce the incidence of Fusarium dieback in commercial avocado groves. Two field tests were conducted to evaluate piperitone as a new repellent for Euwallacea. Beetle captures in baited traps (2-component lure) were compared to captures in baited traps that also contained a piperitone dispenser. In a grove with low numbers of beetles, there was a 65% reduction in captures with the addition of repellent. In a grove with much higher population levels, piperitone resulted in a 50% reduction in captures. In conjunction with field tests, chemical analyses are underway to determine the longevity of piperitone emissions from the dispensers. Initial results indicate that piperitone has good potential as a repellent for pest ambrosia beetles, with repellency that lasts for approximately 10 weeks. This research relates to Objective 1A (Determine behavioral response to semiochemicals that have potential use in control systems) and Objective 1B (Quantification of semiochemicals).
Comparison of trap designs for detection of Euwallacea and other pest ambrosia beetles in Florida. Field tests were conducted in avocado groves to compare efficacy of four commercially available trap designs for detection of ambrosia beetles. In traps baited with the 2-component lure, there were significant differences in captures of Euwallacea, and two trap types were more effective than the current standard (Lindgren funnel traps). Tests are ongoing using traps baited with ethanol lures (a general attractant for ambrosia beetles) to determine efficacy for detection of the overall ambrosia beetle community, particularly species known to be secondary vectors of laurel wilt. This research relates to Objective 2B (Develop optimized trapping systems).
Solvent extraction of semiochemicals from lychee wood. In previous field tests, wood bolts from some lychee cultivars were found to be highly attractive to the redbay ambrosia beetle. Steam-distillation system was developed to obtain volatile compounds from lychee woods. Lychee wood essential oils were found to be rich in sesquiterpenoids. The detailed Gas Chromatography-Mass Spectrometry (GC-MS) analysis of wood oils are in progress to identify chemical constituents. This research relates to Objective 1B (Identify and quantify insect semiochemicals) and the information will be used identify potential new attractants to ambrosia beetle.
Kairomone collection using steam distillation of plant material. In order to identify potential kairomes for ambrosia beetle, native Mexican laurels were selected with the cooperation of the Instituto de Ecología (Veracruz, Mexico). Essential oils from wood samples were obtained using steam distillation methods and GC-MS analysis of volatile wood samples is in progress to identify chemical constituents and the results will be compared to U.S. laurels. This research relates to Objective 1B (Identify and quantify insect semiochemicals).
Field test of new food-based synthetic lure formulations for Caribbean fruit fly. Several new protein-based attractants are under development but have not yet been tested for effectiveness for Caribflies. Field tests were conducted in south Florida to evaluate several synthetic lures based on chemicals emitted from protein baits, to compare capture by these baits with those currently used in fruit fly programs and also to determine longevity of the baits over time. None of the new attractants were more effective than currently used baits. One new protein bait and new synthetic lure were equal to standard protein bait and had improved longevity. These attractants need to be evaluated further to confirm them as alternatives to the standard bait. This research relates to Objective 1B (Identify and quantify insect semiochemicals) and Objective 2A (Develop synthetic lures). Results from this research will be used to identify lures and baits for growers and regulatory agencies.
Development of new methods to identify kairomones for male Mediterranean fruit flies. Progress has been made in research on kairomones for male medflies that relates to Objective 1B (Develop improved systems to collect and identify semiochemicals). Essential oils have provided sources of chemicals that affect behavior of male Mediterranean fruit flies (medflies), but few of the chemicals responsible have been identified. Research evaluated approximately 50 essential oils and plant extracts, and at least 10 were found to be attractive to male medflies. Only small quantities of some of these oils/extracts were available for testing. Therefore a new method used bioassay-guided fractionation using thin-layer chromatography (TLC) system to aide in identifying the chemicals responsible for attraction. Initial research evaluated fractions obtained from tea tree oil and identified 10 chemicals found in the most effective fractions. Research will continue on these chemicals to determine if they can be used to improve control of this pest.
Stereochemistry as a predictor of kairomone activity. A set of compounds representing phenylpropanoids have been evaluated against male Mediterranean fruit flies to provide increased understanding of chemical structure in attraction. In collaboration with the Università di Napoli Federico II (Naples, Italy), 28 phenylpropanoids with different functional groups were evaluated. We found that estragole was the most active kairomone. Results showed that the allylic side chain and p-methoxy phenyl group are important for the kairomone activity. This specific response can be further tested in the field by comparing traps baited with the active compound(s). This research relates to Objective 3B (Stereochemistry of selected compounds) and results will be used to identify new attractants for this pest.
Field tests of pheromone-based lures for the cocoa pod borer. Although a lure based on the female produced pheromone of the cocoa pod borer was developed by earlier researchers, there is no commercial producer in the U.S. and the product available from India performed poorly in our field tests. An effective pheromone-based lure is needed by cocoa growers and for our research on kairomone-based attractants. Research was conducted in collaboration with a U.S. commercial producer and with other ARS scientists. A pheromone lure was developed that is more effective and has increased longevity compared to lure previously available. This research relates to Objective 1B (Identify and quantify insect semiochemicals). Progress has been made on making an effective pheromone-based lure available from a U.S. producer for our research needs and for growers and stakeholders.
Field tests of kairomone-based attractants for the cocoa pod borer. Research related to Objective 2A (Develop natural product lures based on host location and/or feeding cues) has included laboratory and field tests of plant essential oils and extracts as lures for the cocoa pod borer. An essential oil has been identified as a kairomone-based attractant that could be used in traps to monitor and detect adult moths. Research is ongoing to determine if related products are also effective. An invention disclosure is being developed to determine patent potential for this discovery.
Accomplishments
1. Determination of chemical emissions and field longevity of the 2-component lure for pest Euwallacea ambrosia beetles. Invasive ambrosia beetles morphologically similar to the tea shot-hole borer (Euwallacea fornicatus, native to Asia) are now established in the USA, both California and Florida. Members of this cryptic species complex (collectively E. nr. fornicatus) vector fungal pathogens that cause Fusarium dieback disease in host trees, including avocado. ARS researchers at Miami, Florida, previously developed an improved detection system for Euwallacea by combining a-copaene enriched essential oil with quercivorol (FY17 Accomplishment). Subsequent laboratory analyses indicated that both the essential oil and quercivorol contain multiple components, but the attractive chemicals are most likely the negative enantiomer of a-copaene and a trans- isomer of p-menth-2-en-1-ol. Formulation of these compounds in plastic bubble dispensers results in sustained low release of attractants. When tested in the field, the combination lure demonstrated field longevity of 3 months with minimal attraction of non-target beetles. Early in 2018, this new 2-component lure was adopted by SAGARPA (Mexico’s Ministry of Agriculture) for early detection of pest Euwallacea in Mexico.
2. Identification of new reproductive hosts for Euwallacea (E.) in Florida. Euwallacea nr. fornicatus was first detected in Florida in 2002; however, it was not considered a serious threat until 2016 when large numbers of beetles were observed in a commercial avocado grove, accompanied by extensive branch dieback. This outbreak prompted a 12-month survey (utilizing traps baited with the 2-component lure; conducted by ARS researchers at Miami, Forida, in collaboration with the University of Florida and Brooks Tropicals, LLC) to determine the presence and prevalence of this new invasive pest in the avocado production area of Miami-Dade County. This accomplishment relates to Objective 3A (Develop new approaches including improved protocols for pest monitoring and control). Although avocado was found to be a preferred host, the survey identified several new reproductive hosts, including the fruit crop soursop, Annona muricata, as well as native Lysiloma latisiliquum and Albizia lebbeck. These observations indicate that populations of E. nr. fornicatus are increasing in south Florida and other cultivated and native trees are potentially at risk. In addition, the discovery of infested native trees suggests that natural areas in Florida may function as reservoirs for pest E. nr. fornicatus populations capable of dispersing into avocado groves.
3. Patent on wax-based attract-and-kill device for control of the Mediterranean fruit fly. The Mediterranean fruit fly is the most important pest of fruits and vegetables worldwide. Conventional pesticide control is broadcast application of insecticide alone or insecticide mixed with bait. An alternative is attract-and-kill method, which has fewer negative environmental effects because the pesticide is contained in a device and removed at the end of the growing season. ARS researchers at Miami, Florida, developed a matrix that combined a feeding stimulant (sugar), a visual cue (green color) and pesticide mixed with wax. Chemicals that comprised a synthetic food-based lure that was invented previously by ARS scientists at Miami, Florida, and patented by ARS were initially mixed into the wax matrix to attract the flies. However, not enough attractant could be added to provide the longevity needed for field use. Therefore, a box-like device and a method to coat the exterior of the device with the wax matrix were invented in collaboration with scientists from APHIS, Guatemala. The synthetic lure is placed inside the wax coated device to provide the longevity needed. Flies are attracted to the combination of lure and green color in the wax coating. Once flies land on the device, they detect the sugar and feed, obtaining a lethal amount of pesticide. This device could also be used for other pest insects by changing the lure. Field tests have demonstrated that these devices can provide control equivalent to that obtained with broadcast spray application.
Review Publications
Menocal, O., Cruz, L.F., Kendra, P.E., Crane, J.H., Ploetz, R.C., Carrillo, D. 2017. Rearing Xyleborus volvulus (Coleoptera: Curculionidae) on media containing sawdust from avocado or silkbay, with or without Raffaelea lauricola (Ophiostomatales: Ophiostomataceae). Environmental Entomology. 46(6):1275-1283.
Menocal, O., Cruz, L., Kendra, P.E., Crane, J., Cooperband, M.F., Ploetz, R., Carrillo, D. 2018. Xyleborus bispinatus reared on artificial media using sawdust from avocado or silkbay in presence or absence of the laurel wilt pathogen (Raffaelea lauricola). Insects. 9(1):30.
Tabanca, N., Wedge, D.E., Li, X., Gao, Z., Ozek, T., Bernier, U.R., Epsky, N.D., Can Baser, K., Ozek, G. 2018. Biological evaluation, overpressured layer chromatography (OPLC) separation and isolation of a new acetylenic derivative compound from Prangos platychlaena ssp. platychlaena fruit essential oils. Planar Chromatography. 31(1):61-71.
Owens D., W. S. Montgomery, T. I. Narvaez, M. A. Deyrup, and P. E. Kendra. 2017. Evaluation of lure combinations containing essential oils and volatile spiroketals for detection of host-seeking Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae). J. Econ. Entomol. 110(4):1596-1602.
Owens D., Nuessly, G.S., Kendra, P.E., Colquhoun, T.A., Seal, D.R. 2017. Attraction, oviposition preferences, and olfactory responses of corn-infesting Ulidiidae (Diptera) to various host-based substrates. Environ. Entomol. 46(4): 885-894.
Kendra, P.E., Montgomery, W.S., Niogret, J., Tabanca, N., Owens, D., Epsky, N.D. 2018. Utility of essential oils for development of host-based lures for Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae), vector of laurel wilt. Open Chemistry. 16:393-400.
Gardner, E., Gagne, R., Kendra, P.E., Montgomery, W.S., Raguso, R.A., Mcneil, T.T., Zerega, N.J. 2018. A flower in fruit's clothing: Pollination of jackfruit Artocarpus heterophyllus, Moraceae) by a new species of gall midge, Clinodiplosis ultracrepidata sp. nov. (Diptera: Cecidomyiidae). International Journal of Plant Sciences. 179(5):350-367.
Menocal, O., Kendra, P.E., Montgomery, W.S., Crane, J., Carrillo, D. 2018. Vertical distribution and daily flight periodicity of ambrosia beetles (Coleoptera: Curculionidae) in Florida avocado orchards affected by laurel wilt. Journal of Economic Entomology. 111(3): 1190-1196.
Owens, D., Kendra, P.E., Tabanca, N., Narvaez, T.I., Montgomery, W.S., Schnell, E.Q., Carrillo, D. 2019. Quantitative analysis of contents and volatile emissions from a-copaene and quercivorol lures, and longevity for attraction of Euwallacea nr. fornicatus in Florida. Journal of Pest Science. 92(1):237-252. doi:10.1007/s10340-018-0960-6.
Tabanca, N., Ali, Z., Bernier, U.R., Epsky, N.D., Nalbantsoy, A., Khan, I.A., Ali, A. 2018. Bioassay-guided isolation and identification of Aedes aegypti larvicidal and biting deterrent compounds from Veratrum lobelianum. Open Chemistry. 16(1):324-332. https://doi.org/10.1515/chem-2018-0030.
Khaleel, C., Tabanca, N., Buchbauer, G. 2018. Alpha-Terpineol, a natural monoterpene: A review of its biological properties. Open Chemistry. https://doi.org/10.1515/chem-2018-0040.
Kurkcuoglu, M., Tabanca, N., Abbas, A., Khan, I.A., Duran, A., Can Baser, H.K. 2017. Chemical composition of a new taxon, Seseli gummiferum subsp. ilgazense, and its larvicidal activity against Aedes aegypti. DOI: http://doi.org/10.25135/rnp.17.17.05.035. Records of Natural Products.
Owens, D., Cruz, L., Montgomery, W.S., Narvaez, T.I., Schnell, E.Q., Tabanca, N., Duncan, R., Carrillo, D., Kendra, P.E. 2018. Host range expansion and increased damage potential of Euwallacea nr. fornicatus (Coleoptera: Curculionidae) in Florida. Florida Entomologist. 101(2):229-236.
Osek, G., Bedir, E., Tabanca, N., Ali, A., Khan, I.A., Duran, A., Can Baser, H., Ozek, T. 2018. Isolation of eudesmane type sesquiterpene ketone from Prangos heyniae H.Duman & M.F.Watson essential oil and mosquitocidal activity of the essential oils. Open Chemistry. 16:453-467.
