Matthew Siderhurst | United States Department of Agriculture (original) (raw)

Papers by Matthew Siderhurst

Insectes Sociaux, May 10, 2023

The little fire ant (LFA), Wasmannia auropunctata, is a serious invasive pest first reported on H... more The little fire ant (LFA), Wasmannia auropunctata, is a serious invasive pest first reported on Hawaii Island in 1999, and has since spread and established itself across the island. LFA is considered one of the worst 100 invasive species and has significant ecological, agricultural, and public health impacts in invaded areas, which include much of the tropical New World. Although localized eradication efforts have proven successful, they are intensive and difficult to implement. Furthermore, LFA's high invasive-ability resists these control efforts in areas where the species is established and can re-infest treated areas. This research set out to determine whether LFA queens have a suppressant effect on new queen production in nests, as a first step in identifying a potential queen pheromone for LFA. A queen pheromone could offer a means to shutdown LFA reproductive capability, potentially by suppressing the production of new queens or inducing the execution of queens or queen-destined larvae. When queenless experimental nests and polygyne experimental nests were compared, six out of eight queenless nests successfully reared both new alate queens (2.25 queens/nest) and drones (3.63 drones/nest) to adulthood, whereas only three of eight polygyne nests reared sexual larvae that failed to develop to adulthood or even the pupal stage. These results suggest that dealate mature LFA queens suppress the production of new alate queens in LFA nests, and is the first evidence that LFA may utilize a queen pheromone.

Journal of Chemical Ecology, Nov 3, 2006

Coupled gas chromatography-electroantennogram detection (GC-EAD) analysis of volatiles from tropi... more Coupled gas chromatography-electroantennogram detection (GC-EAD) analysis of volatiles from tropical almond fruit, Terminalia catappa L., revealed 22 compounds that were detected by antennae of oriental fruit fly females, Bactrocera dorsalis (Hendel). Both solid-phase microextraction (SPME) and Porapak Q were used for sampling odors in fruit headspace, with SPME collections producing larger EAD responses from a greater number of compounds. Geranyl acetate and methyl eugenol elicited the largest EAD responses. A synthetic blend containing SPME collected, EAD stimulatory compounds showed femalebiased attraction in laboratory wind tunnel bioassays, but heavily male-biased trap captures in a larger olfactometer arena. A nine-component subset of compounds eliciting relatively small EAD responses (EAD minor) and consisting of equal parts ethanol, ethyl acetate, ethyl hexanoate, hexyl acetate, linalyl acetate, ethyl nonanate, nonyl acetate, ethyl cinnamate, and (E)-β-farnesene, attracted mainly females. This EAD minor blend was as attractive to females and much less attractive to males when compared to torula yeast in field cage experiments using glass McPhail traps. Similar results were obtained with outdoor rotating olfactometer tests in which the EAD minor blend was almost completely inactive for males.

Zenodo (CERN European Organization for Nuclear Research), Dec 31, 2021

Coconut rhinoceros beetle (CRB), Oryctes rhinoceros L., is a serious pest of coconut and oil palm... more Coconut rhinoceros beetle (CRB), Oryctes rhinoceros L., is a serious pest of coconut and oil palms throughout Southeast Asia and the Pacific. CRB was found on Guam in 2007 and, despite suppression efforts, has subsequently spread across the island. The CRB population on Guam is genetically different from other populations in Asia and the Pacific, and is considered a new invasive biotype (termed CRB-G). CRB-G is apparently resistant to Oryctes rhinoceros nudivirus, the preferred biocontrol agent for this pest. CRB populations are typically controlled with a combination of biocontrol, pheromone traps, and breeding site removal. A field trial was performed at six locations on Guam to test potential improvements to standard CRB pheromone trapping with oryctalure (ethyl 4-methyloctanoate). Two modifications were tested, 1) addition of ultraviolet light emitting diodes (UV LEDs), and 2) reduction of pheromone release rate. Addition of UV LED light sources to pheromone traps significantly increased trap catch by 2.85 times. Reduction in oryctalure release rate by up to an order of magnitude did not significantly change CRB capture rate. Further, when linear regression analyses of CRB trap capture rate as a function of pheromone release rate were conducted for traps with and without UV LEDs separately, only a very weak relationship between trap capture and oryctalure release rate was observed and only when a UV LED was present. Results suggest that addition of UV LED light sources to pheromone traps could improve detection trapping of CRB and that reduction of pheromone release rate could extend service life of lures without changing capture rate.

Sociobiology, 2005

Although termites are known to contain the fluorescent alkaloid norharmane, the physiological dis... more Although termites are known to contain the fluorescent alkaloid norharmane, the physiological distribution and biosynthetic origin of this compound has not previously been reported. Histological observations under UV light showed that norharmane is contained in the termite internal fluids. This is in contrast to the physiological distribution of norharmane in scorpions, in which the alkaloid is contained in the epicuticle. GC/MS analyses showed that norharmane is mainly located in the hemolymph with hemolymph removal causing the loss of all observable fluorescence in termite carcasses. GC/MS analyses further showed that norharmane was biosynthesized as a metabolite from endosymbionts cultured in isolation from Reticulitermes tibialis and R. flavipes termites. Actinomycetes bacteria are likely candidates as the endosymbionts that biosynthesize norharmane, because they are components of the termite gut and are the only microbes known to produce norharmane.

Environmental Entomology, Mar 21, 2015

Measuring and modeling the attractiveness of semiochemical-baited traps is of significant importa... more Measuring and modeling the attractiveness of semiochemical-baited traps is of significant importance to detection, delimitation, and control of invasive pests. Here, we describe the results of field mark-release-recapture experiments with Ceratitis capitata (Wiedemann) and Bactrocera dorsalis (Hendel) to estimate the relationship between distance from a trap baited with trimedlure and methyl eugenol, respectively, and probability of capture for a receptive male insect. Experiments were conducted using a grid of traps with a central release point at two sites on Hawaii Island, a Macadamia orchard on the East side of the island and a lava field on the West side. We found that for B. dorsalis and methyl eugenol there is a 65% probability of capture at 36mfromasingletrap,regardlessofhabitat.ForC.capitata,wefounda6536 m from a single trap, regardless of habitat. For C. capitata, we found a 65% probability of capture at a distance of 36mfromasingletrap,regardlessofhabitat.ForC.capitata,wefounda6514 m from a single trap in the orchard and 7 m in the lava field. We also present results on the spatial and temporal pattern of recaptures. The attraction data are analyzed via a hyperbolic secant-based capture probability model.

Plant Disease, Oct 1, 2007

Gray kernel is an important disease of macadamia (Macadamia integrifolia) that affects the qualit... more Gray kernel is an important disease of macadamia (Macadamia integrifolia) that affects the quality of kernels, causing gray discoloration and a permeating, foul odor. Gray kernel symptoms were produced in raw, in-shell kernels of three cultivars of macadamia that were inoculated with strains of Enterobacter cloacae. Koch's postulates were fulfilled for three strains, demonstrating that E. cloacae is a causal agent of gray kernel. An inoculation protocol was developed to consistently reproduce gray kernel symptoms. Among the E. cloacae strains studied, macadamia strain LK 0802-3 and ginger strain B193-3 produced the highest incidences of disease (65 and 40%, respectively). The other macadamia strain, KN 04-2, produced gray kernel in 21.7% of inoculated nuts. Control treatments had 1.7% gray kernel symptoms. Some abiotic and biotic factors that affected incidence of gray kernel in inoculated kernels were identified. Volatiles of gray and nongray kernel samples also were analyzed. Ethanol and acetic acid were present in nongray and gray kernel samples, whereas volatiles from gray kernel samples included the additional compounds, 3-hydroxy-2-butanone (acetoin), 2,3-butanediol, phenol, and 2methoxyphenol (guaiacol). This is believed to be the first report of the identification of volatile compounds associated with gray kernel.

Entomologia Experimentalis Et Applicata, Oct 1, 2007

The nettle caterpillar, Darna pallivitta (Moore) (Lepidoptera: Limacodidae), is an invasive pest ... more The nettle caterpillar, Darna pallivitta (Moore) (Lepidoptera: Limacodidae), is an invasive pest on the island of Hawai’i, causing defoliation of ornamental nursery stock and posing a human health hazard due to their urticating hairs that can cause painful stings. Wind tunnel and field tests with 2–3‐day‐old moths revealed behavioral responses of males to caged females, which is indicative of a female‐released sex pheromone. Coupled gas chromatography‐electroantennogram detection (GC‐EAD) analysis of female abdominal tip extracts revealed two male electroantennographically active compounds produced by female D. pallivitta. Mass spectral analysis and subsequent synthesis identified the active compounds as n‐butyl (E)‐7,9‐decadienoate (major component) and ethyl (E)‐7,9‐decadienoate (minor component), both structurally similar to sex pheromone components previously reported from related Darna spp. Additionally, methyl (E)‐7,9‐decadienoate was identified from female abdominal tip extracts and a strong EAD response was elicited by the synthetic compound. n‐Butyl (E)‐7,9‐decadienoate was the only component detected by solid phase microextraction (SPME) collections from single calling female moths, however, the apparent absence of minor components may be a result of their lower abundance. Field trials showed significant attraction of male moths to all lures containing the n‐butyl ester, while the methyl and ethyl esters did not increase trap captures at the levels and ratios tested. Synthetic pheromone lures (2.5 mg) outperformed virgin moths as attractant baits and could be used for monitoring D. pallivitta populations of the island of Hawai’i and detection on other Hawai’ian islands and at ports and nurseries that receive plants from Hawai’i (e.g., California and Florida).

Pest Management Science, Feb 9, 2010

BACKGROUND: The banana moth, Opogona sacchari Bojer, is a polyphagous agricultural pest in many t... more 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)-2,13octadecadienal. 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 µg lures of (E, Z)-2,13octadecadienal 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 males and can be used as a monitoring lure of populations of this moth.

Research Ideas and Outcomes, Oct 27, 2022

Coconut rhinoceros beetle (CRB), a major pest of coconut and oil palms, is causing severe economi... more Coconut rhinoceros beetle (CRB), a major pest of coconut and oil palms, is causing severe economic and environmental damage following recent invasions of several Pacific islands. Population suppression and eradication of this pest requires location and destruction of active and potential breeding sites where all life stages aggregate. Three search tactics for discovering breeding sites have been used with limited success: visual search by humans, search with assistance from detector dogs and search by tracking CRB adults fitted with radio transmitters. Here, we suggest a fourth search tactic: releasing CRB adults fitted with harmonic radar tags to locate breeding sites. Our idea is to find static end points for tags which accumulate at breeding sites, rather than active tracking of individual beetles. We plan to use commercially available hand-held harmonic radar devices. If we are successful, this technique may be useful for locating other insects which aggregate, such as hornets and other social insects.

Scientific Reports, Mar 22, 2022

Interspecies hybrids can express phenotypic traits far outside the range of parental species. The... more Interspecies hybrids can express phenotypic traits far outside the range of parental species. The atypical traits of hybrids provide insight into differences in the factors that regulate the expression of these traits in the parental species. In some cases, the unusual phenotypic traits of hybrids can lead to phenotypic dysfunction with hybrids experiencing reduced survival or reproduction. Cuticular hydrocarbons (CHCs) in insects are important phenotypic traits that serve several functions, including desiccation resistance and pheromones for mating. We used gas chromatography mass spectrometry to investigate the differences in CHC production between two closely related sympatric Hawaiian picture-wing Drosophila species, Drosophila heteroneura and D. silvestris, and their F1 and backcross hybrid offspring. CHC profiles differed between males of the two species, with substantial sexual dimorphism in D. silvestris but limited sexual dimorphism in D. heteroneura. Surprisingly, F1 hybrids did not produce three CHCs, and the abundances of several other CHCs occurred outside the ranges present in the two parental species. Backcross hybrids produced all CHCs with greater variation than observed in F1 or parental species. Overall, these results suggest that the production of CHCs was disrupted in F1 and backcross hybrids, which may have important consequences for their survival or reproduction. Interspecies hybrids that express phenotypic traits far outside the range present in the parental species can provide insights into the factors that regulate the expression of these traits 1. These unusual phenotypic traits in hybrids can also reflect a type of phenotypic dysfunction in which hybrid individuals experience reduced survival or reproduction 2,3. Several types of gene interactions may be involved in hybrid disruption, such as cis-trans regulation or post-transcriptional processes, including mRNA splicing and processing 4,5. Further, translational alterations resulting in changed amino acids may result in proteins incapable of interacting, thus producing less-fit hybrid phenotypes 6. Cuticular hydrocarbons (CHCs) are abundant components of insect cuticles 7,8 that are produced through complex biochemical processes 9,10 and involve the interaction of genes on different chromosomes 11. CHCs display a wide range of distinct compounds that vary across insect taxa and occur as a complex mixture of hydrophobic linear, branched, saturated, and unsaturated compounds 11-13. CHCs are known to act as pheromones and influence a wide variety of behaviors, including courtship, mate discrimination, learning, aggregation, and dominance 5,8,14 , and they have a strong influence on individual fitness, helping insects to resist starvation 15 , tolerate extreme environments 16 , and prevent desiccation 17-19. In D. melanogaster, the alteration or disruption of genes involved in CHC biosynthesis can result in the complete absence 20 or overproduction 21 of CHCs, changes that have the potential to negatively impact mating, copulation behavior, and survivability 10,22 .

Journal of the Science of Food and Agriculture, Feb 21, 2018

BACKGROUNDNoni fruit (Morinda citrifolia L., Rubiaceae) has been used in traditional medicine thr... more BACKGROUNDNoni fruit (Morinda citrifolia L., Rubiaceae) has been used in traditional medicine throughout the tropics and subtropics and is now attracting interest in western medicine. Fermented noni juice is of particular interest for its promising antitumor activity. The present study collected and analyzed volatiles released at nine time intervals by noni fruit during ripening and fermentation using headspace autosampling coupled to gas chromatography–mass spectrometry.RESULTSTwenty‐three noni volatiles were identified and relatively quantified. In addition to volatiles previously identified in noni, four novel volatile 3‐methyl‐2/3‐butenyl esters were identified via the synthesis of reference compounds. Principle component analysis (PCA) and canonical discriminant analysis (CDA) were used to facilitate multidimensional pattern recognition. PCA showed that ripening noni fruit cluster into three groups, pre‐ripe, fully ripe (translucent) and fermented, based on released volatiles. CDA could 83.8% correctly classify noni samples when all ripeness stages were analyzed and 100% when samples were classified into the three PCA groupings.CONCLUSIONThe results of the present study confirm the identities of 3‐methyl‐2/3‐butenyl esters, both novel and previously identified, through the synthesis of reference compounds. These esters constitute a large percentage of the volatiles released by fully ripe and fermented noni and likely produced from the decomposition of noniosides, a group of unique glucosides present in the fruit. © 2017 Society of Chemical Industry

Bactrocera latifrons is a tephritid fruit fly (Diptera: Tephritidae) which has a host list of 59 ... more Bactrocera latifrons is a tephritid fruit fly (Diptera: Tephritidae) which has a host list of 59 plant species from 14 plant families, with over 70% of the host plant species coming from the plant families Solanaceae and Cucurbitaceae. Bactrocera latifrons is of primarily Asian distribution, but its range has expanded through introductions into Hawaii, Okinawa (Japan), Tanzania, and Kenya. The documented introductions into countries outside its native distribution show that this species poses a risk of introductions into other countries where it does not presently occur, particularly through the movement of infested fruit. As with other tephritid fruit fly species, establishment of B. latifrons can have significant economic consequences, including damage and loss of food production, as well as requirements for implementation of costly quarantine treatments to permit export of commodities susceptible to infestation by B. latifrons and inspection of susceptible imported commodities. Because of the economic importance of B. latifrons, reliable methods are needed to detect, monitor, and control this species. We conducted field trials with a wild B. latifrons population, supported by the invasive weed, turkeyberry, Solanum torvum (Solanaceae), to compare attractiveness of prospective new lures with several attractants that have often been used for detection and/or monitoring of tephritid fruit flies. The tests reported here have again shown higher B. latifrons catch in traps baited with alpha-ionol + cade oil relative to traps baited with protein baits. Among the attractants to which both male and female B. latifrons are attracted, fly response is significantly better to a Solulys AST-based protein bait than to other attractants tested. Beyond this, there was no significant difference in catch among the (wet) torula yeast baited trap and four (dry) alternative attractants (ammonia, biolure, rainbow plug and cucumber volatile plug). This shows that these dry trap alternatives have a comparable ability to catch B. latifrons adults as a wet protein bait trap (though not comparable to a Solulys AST-based wet trap).

Journal of Chemical Ecology, Nov 5, 2014

The little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), is an invasive ant... more The little fire ant, Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae), is an invasive ant with negative impacts on both biodiversity and agriculture throughout the tropics and subtropics. Field experiments were conducted in order to elucidate the relative attractiveness of the enantiomers o f t h e a l a r m p h e r o m o n e s , 2 , 5-d i m e t h y l-3-(2methylbutyl)pyrazine and 3-methyl-2-(2-methylbutyl)pyrazine. The enantiomers tested were synthesized from commercially available (S)-2-methylbutan-1-ol or kinetically resolved (R)-2methylbutan-1-ol, prepared using Pseudomonas cepacia lipase (PCL). Bioassays conducted in a macadamia orchard on the island of Hawaii demonstrated that W. auropunctata were preferentially attracted to the (S)-enantiomers of both alkyl pyrazines over the racemic mixtures in all experiments. To our knowledge, this is the first instance of differential attraction of ants to the enantiomers of chiral pyrazine pheromones despite many examples of these compounds in the literature. In addition, using a chiral column it was determined that (S)-2,5-dimethyl-3-(2m e t h y l b u t y l) p y r a z i n e a n d (S)-3-m e t h y l-2-(2methylbutyl)pyrazine are the only enantiomers produced by W. auropunctata.

PLOS ONE

Tephritid fruit flies, such as the melon fly,Zeugodacus cucurbitae, are major horticultural pests... more Tephritid fruit flies, such as the melon fly,Zeugodacus cucurbitae, are major horticultural pests worldwide and pose invasion risks due primarily to international trade. Determining movement parameters for fruit flies is critical to effective surveillance and control strategies, from setting quarantine boundaries after incursions to development of agent-based models for management. While mark-release-recapture, flight mills, and visual observations have been used to study tephritid movement, none of these techniques give a full picture of fruit fly movement in nature. Tracking tagged flies offers an alternative method which has the potential to observe individual fly movements in the field, mirroring studies conducted by ecologists on larger animals. In this study, harmonic radar (HR) tags were fabricated using superelastic nitinol wire which is light (tags weighed less than 1 mg), flexible, and does not tangle. Flight tests with wild melon flies showed no obvious adverse effects of...

Research Ideas and Outcomes

Presented at the Entomological Society of America Annual Meeting, Portland OR, November 19, 2014.