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Matthew P Ayres - One of the best experts on this subject based on the ideXlab platform.

  • Biology, demography and community interactions of Tarsonemus (Acarina: Tarsonemidae) mites phoretic on Dendroctonus frontalis
    2013
    Co-Authors: Co Leoptera Sco Lytidae, Kier D. Klepzigt, Maria J. Lornbardero, John C. Mosert, Matthew P Ayres
    Abstract:

    1 Dendroctonus frontalis, the southern pine beetle, is associated with a diverse community of fungi and mites that are phoretic on the adult beetles. Tarsonernus ips, T. kranzti and T. fusarii (Acarina: Tarsonernidae) may interact within this community in ways that link the population dynamics of D. frontalis, the mites and three dominant species of fungi. We explored species associations by comparing the dietary suitability of different fungi for Tarsonemus spp. 2 All three mite species fed and reproduced at high rates when feeding on the bluestain fungus, Ophiostoma minus, which is an antagonist of D. frontalis larvae. 3 Mites also had positive population growth rates when feeding upon Ceratocystiopsis ranaculosus, one of the mycangial fungi, but could barely reproduce when feeding upon Entomocorticium sp. A, the rnycangial fungus that is most suitable for D.,frontalis. 4 During the time from colonization of a tree by D. frontalis adults until departure from the tree of their progeny ( = 40 d at 30 "C), mite populations feeding upon 0. minus can increase by factors of up to 209 (T. fusarii), 173 (T. ips) or 384 (T. kmntzi). These high growth rates are allowed by rapid development (age of first reproduction = 8-9 d), high fecundity ( = 1 egg/d) and high longevity (> 28 d). 5 Precocious mating increases the chance that females are mated prior to colonizing a new tree and arrhenotokous parthenogenesis permits reproduction by unmated females. 6 Tarsonemus mites may introduce negative feedback into D. frontalis population dynamics by generating indirect interactions between D. frontalis and 0. minus

  • Temperature alters the relative abundance and population growth rates of species within the Dendroctonus frontalis (Coleoptera: Curculionidae) community.
    Environmental entomology, 2011
    Co-Authors: Luke M. Evans, Richard W Hofstetter, Matthew P Ayres, Kier D. Klepzig
    Abstract:

    Temperature has strong effects on metabolic processes of individuals and demographics of populations, but effects on ecological communities are not well known. Many economically and ecologically important pest species have obligate associations with other organisms; therefore, effects of temperature on these species might be mediated by strong interactions. The southern pine beetle (Dendroctonus frontalis Zimmermann) harbors a rich community of phoretic mites and fungi that are linked by many strong direct and indirect interactions, providing multiple pathways for temperature to affect the system. We tested the effects of temperature on this community by manipulating communities within naturally infested sections of pine trees. Direct effects of temperature on component species were conspicuous and sometimes predictable based on single-species physiology, but there were also strong indirect effects of temperature via alteration of species interactions that could not have been predicted based on autecological temperature responses. Climatic variation, including directional warming, will likely influence ecological systems through direct physiological effects as well as indirect effects through species interactions.

  • Evolutionary ecology of pheromone signaling in Dendroctonus frontalis
    2007
    Co-Authors: Deepa S. Pureswaran, Brian T. Sullivan, Matthew P Ayres
    Abstract:

    Although studies of pheromone production in the southern pine beetle (Dendroctonus frontalis) extend back to the dawn of chemical ecology, it is only recently that instrumentation has become sufficiently sensitive to measure pheromone production of individual beetles. Now, recent studies have revealed surprisingly high variation among individuals in their pheromone production. This seems paradoxical because pheromone signals in tree-killing bark beetles are apparently linked to fitness and have high heritability.

  • Differential impacts of the southern pine beetle, Dendroctonus frontalis, on Pinus palustris and Pinus taeda
    Canadian Journal of Forest Research, 2007
    Co-Authors: Nicholas A. Friedenberg, Brenda M. Whitedb.m. Whited, Daniel H. Slone, Sharon J. Martinsons.j. Martinson, Matthew P Ayres
    Abstract:

    Patterns of host use by herbivore pests can have serious consequences for natural and managed ecosystems but are often poorly understood. Here, we provide the first quantification of large differential impacts of the southern pine bee- tle, Dendroctonus frontalis Zimmermann, on loblolly pine, Pinus taeda L., and longleaf pine, Pinus palustris P. Mill., and evaluate putative mechanisms for the disparity. Spatially extensive survey data from recent epidemics indicate that, per square kilometre, stands of loblolly versus longleaf pine in four forests (380-1273 km 2 ) sustained 3-18 times more local infestations and 3-116 times more tree mortality. Differences were not attributable to size or age structure of pine stands. Using pheromone-baited traps, we found no differences in the abundance of dispersing D. frontalis or its predator Thanasi- mus dubius Fabricius between loblolly and longleaf stands. Trapping triggered numerous attacks on trees, but the pine spe- cies did not differ in the probability of attack initiation or in the surface area of bark attacked by growing aggregations. We found no evidence for postaggregation mechanisms of discrimination or differential success on the two hosts, suggest- ing that early colonizers discriminate between host species before a pheromone plume is present. Resume´ : Le patron d'utilisation des hotes par les ravageurs herbivores peut avoir de serieuses consequences pour les eco- systemes naturels et amenages mais elles sont souvent mal connues. Dans cet article, nous quantifions pour la premiere fois les impacts du dendroctone meridional du pin, Dendroctonus frontalis Zimmermann, qui sont tres differents sur le pin aen- cens, Pinus taeda L., et le pin des marais, Pinus palustris P. Mill., et nous evaluons les mecanismes qui pourraient expliquer cette disparite ´. Les donnees d'un inventaire couvrant un vaste territoire et portant sur des epidemies recentes indiquent que les peuplements de pin aencens ont subi 3-18 fois plus d'infestations locales et 3-116 fois plus de mortalitepar kilometre carreque les peuplements de pin des marais dans quatre forets (380-1273 km 2 ). Ces differences n'etaient pas attribuables a la structure d'age ou de dimension des peuplements de pin. Al'aide de trappes appatees avec des pheromones, nous n'avons observeaucune difference dans l'abondance de D. frontalis alors qu'il se dispersait ni de son predateur, Thanasimus dubius Fabricius, entre les peuplements de pin aencens et de pin des marais. Le piegeage a provoqueplusieurs attaques sur les ar- bres mais il n'y avait pas de difference entre les especes de pin quant ala probabilitedu declenchement d'une attaque ni quant a la superficie d'ecorce attaquee par le regroupement d'un nombre croissant d'insectes. Nous n'avons trouveaucun in- dice de discrimination ou de difference de succes dues ades mecanismes de regroupement a posteriori sur les deux hotes, ce qui indique que les insectes pionniers distinguent l'espece hote avant qu'une traoˆnee de pheromone soit presente. (Traduit par la Redaction)

  • IMPACT OF MINIMUM WINTER TEMPERATURES ON THE POPULATION DYNAMICS OF Dendroctonus frontalis
    Ecological applications : a publication of the Ecological Society of America, 2007
    Co-Authors: J. Khai Trân, Ronald F. Billings, Tiina Ylioja, Jacques Régnière, Matthew P Ayres
    Abstract:

    Predicting population dynamics is a fundamental problem in applied ecology. Temperature is a potential driver of short-term population dynamics, and temperature data are widely available, but we generally lack validated models to predict dynamics based upon temperatures. A generalized approach involves estimating the temperatures experienced by a population, characterizing the demographic consequences of physiological responses to temperature, and testing for predicted effects on abundance. We employed this approach to test whether minimum winter temperatures are a meaningful driver of pestilence from Dendroctonus frontalis (the southern pine beetle) across the southeastern United States. A distance-weighted interpolation model provided good, spatially explicit, predictions of minimum winter air temperatures (a putative driver of beetle survival). A Newtonian heat transfer model with empirical cooling constants indicated that beetles within host trees are buffered from the lowest air temperatures by 1–4°C (depending on tree diameter and duration of cold bout). The life stage structure of beetles in the most northerly outbreak in recent times (New Jersey) were dominated by prepupae, which were more cold tolerant (by >3°C) than other life stages. Analyses of beetle abundance data from 1987 to 2005 showed that minimum winter air temperature only explained 1.5% of the variance in interannual growth rates of beetle populations, indicating that it is but a weak driver of population dynamics in the southeastern United States as a whole. However, average population growth rate matched theoretical predictions of a process-based model of winter mortality from low temperatures; apparently our knowledge of population effects from winter temperatures is satisfactory, and may help to predict dynamics of northern populations, even while adding little to population predictions in southern forests. Recent episodes of D. frontalis outbreaks in northern forests may have been allowed by a warming trend from 1960 to 2004 of 3.3°C in minimum winter air temperatures in the southeastern United States. Studies that combine climatic analyses, physiological experiments, and spatially replicated time series of population abundance can improve population predictions, contribute to a synthesis of population and physiological ecology, and aid in assessing the ecological consequences of climatic trends.

María J. Lombardero - One of the best experts on this subject based on the ideXlab platform.

  • Effects of pine oleoresin on colonization and population dynamics of Dendroctonus frontalis
    2005
    Co-Authors: Richard W Hofstetter, Kier D. Klepzig, María J. Lombardero, Matthew P Ayres
    Abstract:

    1. The effects of tree oleoresin and beetle colonization rates on host-tree colonization and population dynamics of an eruptive pine bark beetle, Dendroctonus frontalis were evaluated. Three specific questions were addressed: Are inducible responses of the pine resin system a defense against D. frontalis? Does the tree resin system promote positive density dependence in D. frontalis? Do D. frontalis regulate their attack densities to maximize per capita reproduction? 1 2 3 4 5 6 7 8 9

  • strong indirect interactions of tarsonemus mites acarina tarsonemidae and Dendroctonus frontalis coleoptera scolytidae
    Oikos, 2003
    Co-Authors: María J. Lombardero, Matthew P Ayres, Richard W Hofstetter, John C Moser, Kier D Lepzig
    Abstract:

    Phoretic mites of bark beetles are classic examples of commensal ectosymbionts. However, many such mites appear to have mutualisms with fungi that could themselves interact with beetles. We tested for indirect effects of phoretic mites on Dendroctonus frontalis, which attacks and kills pine trees in North America. Tarsonemus mites are known to carry ascospores of Ophiostoma minus, which tends to outcompete the mutualistic fungi carried by D. frontalis. Experimental additions and removals of mites from beetles demonstrated that Tarsonemus propagate O. minus in beetle oviposition galleries. Furthermore, the abundance of Tarsonemus and O. minus tended to covary in nature. These results verified a strong mutualism between Tarsonemus and O. minus. Results also indicated that O. minus is an antagonist of D. frontalis: beetle larvae seldom survived in the presence of O. minus (compared to 83% survival elsewhere). Apparently, this is an indirect result of O. minus outcompeting the two species of mycangial fungi that are critical to beetle nutrition. Thus, Tarsonemus mites close a loop of species interactions that includes a commensalism (mites and beetles), a mutualism (mites and O. minus), asymmetric competition (O. minus and mycangial fungi), and another mutualism (mycangial fungi and beetles). This interaction system produces negative feedback that could contribute to the endogenous population dynamics of D. frontalis. Reproductive rate of Tarsonemus was more temperature-sensitive than beetle generation time (which constrains the time for mite reproduction within a tree). This differential temperature sensitivity produces a narrow range of temperatures (centred at 27°C) in which mite reproduction per D. frontalis generation can attain its maximum of 100 mites/beetle. Consequently, seasonal oscillations in temperature are predicted to produce oscillations in the D. frontalis community, and climatic differences between regions could influence the community to dampen or exacerbate the cyclical outbreak dynamics of D. frontalis.

  • Relative Suitability of Virginia Pine and Loblolly Pine as Host Species for Dendroctonus frontalis (Coleoptera: Scolytidae)
    Environmental Entomology, 2003
    Co-Authors: Jessica S. Veysey, Matthew P Ayres, María J. Lombardero, Richard W Hofstetter, Kier D. Klepzig
    Abstract:

    Abstract Dendroctonus frontalis Zimmerman is a major disturbance agent in American pine forests, but attack preferences for various host species, and their relative suitability for reproduction, are poorly known. We studied patterns of beetle attack and reproduction during an infestation of stands containing Virginia pine and loblolly pine. Nearly all Virginia pine were attacked and killed, whereas a third of the loblolly pine escaped attack. Among attacked trees, the density of landings and attacks on Virginia pine was 56–106% higher than on loblolly pine at one site, whereas it was similar between species at another site. Paradoxically, D. frontalis preferred the host that was least suitable for reproduction: mean ± SE = 0.89 ± 0.33 versus 4.65 ± 1.40 progeny/attack in Virginia pine versus loblolly pine. Poor reproduction in Virginia pine was attributable to increased adult mortality, decreased oviposition, and decreased larval survival. Phloem thickness and nitrogen content were similar between the two...

  • Biology, demography and community interactions of Tarsonemus (Acarina: tarsonemidae) mites phoretic on Dendroctonus frontalis (Coleoptera: Scolytidae)
    Agricultural and Forest Entomology, 2000
    Co-Authors: María J. Lombardero, Kier D. Klepzig, John C Moser, Matthew P Ayres
    Abstract:

    1- Dendroctonus frontalis, the southern pine beetle, is associated with a diverse community of fungi and mites that are phoretic on the adult beetles. Tarsonemus ips, T. kranzti and T. fusarii (Acarina: Tarsonemidae) may interact within this community in ways that link the population dynamics of D. frontalis, the mites and three dominant species of fungi. We explored species associations by comparing the dietary suitability of different fungi for Tarsonemus spp. 2 - All three mite species fed and reproduced at high rates when feeding on the bluestain fungus, Ophiostoma minus, which is an antagonist of D. frontalis larvae. 3 - Mites also had positive population growth rates when feeding upon Ceratocystiopsis ranaculosus, one of the mycangial fungi, but could barely reproduce when feeding upon Entomocorticium sp. A, the mycangial fungus that is most suitable for D. frontalis. 4 - During the time from colonization of a tree by D. frontalis adults until departure from the tree of their progeny (approximately equal to 40 d at 30 °C), mite pulations feeding upon O. minus can increase by factors of up to 209 (T. fusarii), 173 (T. ips) or 384 (T. krantzi). These high growth rates are allowed by rapid development (age of first reproduction = 8-9 d), high fecundity (approximately equal to 1 egg/d) and high longevity (> 28 d). 5 - Precocious mating increases the chance that females are mated prior to colonizing a new tree and arrhenotokous parthenogenesis permits reproduction by unmated females. 6 - Tarsonemus mites may introduce negative feedback into D. frontalis population dynamics by generating indirect interactions between D. frontalis and O. minus.

  • Climate and the northern distribution limits of Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae)
    Journal of Biogeography, 1999
    Co-Authors: Matthew J. Ungerer, Matthew P Ayres, María J. Lombardero
    Abstract:

    The southern pine beetle, Dendroctonus frontalis, is among the most important agents of ecological disturbance and economic loss in forests of the south-eastern United States. We combined physiological measurements of insect temperature responses with climatic analyses to test the role of temperature in determining the northern distribution limits of D. frontalis. Laboratory measurements of lower lethal temperatures and published records of mortality in wild populations indicated that air temperatures of -16∞ should result in almost 100% mortality of D. frontalis. The distribution limits for D. frontalis approximate the isoline corresponding to an annual probability of 0.90 of reaching £-16 ∞C. Thus, D. frontalis have been found about as far north as they could possibly occur given winter temperature regimes. At latitudes from 39∞ N (southern Ohio) to 33∞ N (central Alabama), winter temperatures must exert high mortality on D. frontalis populations in at least one year out of ten. In contrast, we reject the hypotheses that summer temperatures or the distribution of host trees constrain the northern distribution of D. frontalis. Because of the short generation time of D. frontalis, its high dispersal abilities, and the cosmopolitan distribution of suitable host trees, changes in either the mean or variance of minimum annual temperatures could have almost immediate effects on regional patterns of beetle infestations. We estimate that an increase of 3 ∞C in minimum annual temperature could extend the northern distribution limits by 170 km. Increases or decreases in the variance of minimum annual temperatures would further relax climatic constraints on the northern distribution limits of D. frontalis. Results emphasize the ecological importance of spatial and temporal variability in minimum annual temperatures. The physiologically based models provide a tool for guiding land management decisions in forests and illustrate a general approach for predicting the regional effects of climatic patterns on the distribution of organisms.

Brian T. Sullivan - One of the best experts on this subject based on the ideXlab platform.

  • Semiochemicals in the natural history of southern pine beetle, Dendroctonus frontalis Zimmermann and their role in pest management.
    Advances in Insect Physiology, 2016
    Co-Authors: Brian T. Sullivan
    Abstract:

    Abstract The southern pine beetle, Dendroctonus frontalis Zimmermann is generally considered to be one of the most significant biotic mortality agents of pines within North America, with a range stretching from New England to eastern Texas and from Arizona south to Nicaragua. As with other aggressive pine beetles, it relies on semiochemicals for coordinating the mass attacks necessary for colonization of healthy pines. Over the past 50 years its chemical ecology has received extensive study aimed at development of effective and practical semiochemical-based management strategies which might replace the destructive and costly techniques in practice. I review the literature on the chemical ecology of this insect with particular attention to the functional categorizations assigned to different semiochemicals and the data underlying these assignments. Additionally, I attempt to identify conflicts and knowledge gaps within current understanding of the chemical ecology of this insect that might represent a significant hindrance to progress in development of effective semiochemical-based management strategies.

  • Enantiospecific responses of southern pine beetle (Dendroctonus frontalis) and its clerid predator, Thanasimus dubius, to α-pinene
    Chemoecology, 2015
    Co-Authors: Jenny C. Staeben, Brian T. Sullivan, John T. Nowak, Kamal J. K. Gandhi
    Abstract:

    Multi-trophic interactions between pine bark beetles, their host trees, and predators are mediated in part by volatile terpenes in host tree oleoresin that can influence aggregation and/or host finding by both prey and predator species. The southern pine beetle, Dendroctonus frontalis Zimmermann, mass-attacks pine trees in response to its aggregation pheromone combined with host resin odors including α-pinene. We investigated discrimination of α-pinene enantiomers in olfactory responses of D. frontalis , and in behavioral responses of D. frontalis and its major clerid predator, Thanasimus dubius (Fabricius). Trapping trials in the spring and fall assessed attraction of both species to the D. frontalis aggregation pheromone components, frontalin and endo-brevicomin, either alone or in combination with α-pinene lures of differing enantiomeric compositions. α-Pinene lures enriched with the (+)-enantiomer (97.5 %) increased D. frontalis catches significantly more than (−)-enriched (93 %) lures, but did not differ from racemic lures. Sexes of D. frontalis did not differ from one another in their responses to the enantiomers, and there was no difference in lure discrimination by D. frontalis and T. dubius . Thanasimus dubius did not distinguish between different α-pinene enantiomers. Dose–response electroantennogram studies of D. frontalis indicated that their antennae had a slightly lower response threshold to (+) than (−)-α-pinene. Each enantiomer habituated the antennae more to itself than to its antipode, implying the existence of olfactory receptors with differing affinities for enantiomers. The preference of D. frontalis for (+)-α-pinene may affect its host selection behavior, and should be considered in population monitoring lures.

  • Enantiospecific responses of southern pine beetle (Dendroctonus frontalis) and its clerid predator, Thanasimus dubius, to a-pinene.
    Chemoecology, 2014
    Co-Authors: Jenny C. Staeben, Brian T. Sullivan, John T. Nowak, Kamal J. K. Gandhi
    Abstract:

    Multi-trophic interactions between pine bark beetles, their host trees, and predators are mediated in part by volatile terpenes in host tree oleoresin that can influence aggregation and/or host finding by both prey and predator species. The southern pine beetle, Dendroctonus frontalis Zimmermann, mass-attacks pine trees in response to its aggregation pheromone combined with host resin odors including α-pinene. We investigated discrimination of α-pinene enantiomers in olfactory responses of D. frontalis, and in behavioral responses of D. frontalis and its major clerid predator, Thanasimus dubius (Fabricius). Trapping trials in the spring and fall assessed attraction of both species to the D. frontalis aggregation pheromone components, frontalin and endo-brevicomin, either alone or in combination with α-pinene lures of differing enantiomeric compositions. α-Pinene lures enriched with the (+)-enantiomer (97.5 %) increased D. frontalis catches significantly more than (−)-enriched (93 %) lures, but did not differ from racemic lures. Sexes of D. frontalis did not differ from one another in their responses to the enantiomers, and there was no difference in lure discrimination by D. frontalis and T. dubius. Thanasimus dubius did not distinguish between different α-pinene enantiomers. Dose–response electroantennogram studies of D. frontalis indicated that their antennae had a slightly lower response threshold to (+) than (−)-α-pinene. Each enantiomer habituated the antennae more to itself than to its antipode, implying the existence of olfactory receptors with differing affinities for enantiomers. The preference of D. frontalis for (+)-α-pinene may affect its host selection behavior, and should be considered in population monitoring lures.

  • Two Species within Dendroctonus frontalis (Coleoptera: Curculionidae): Evidence from Morphological, Karyological, Molecular, and Crossing Studies
    Annals of the Entomological Society of America, 2014
    Co-Authors: Francisco Armendáriz-toledano, Brian T. Sullivan, Alicia Niño, Jorge Macias-samano, Stephen R. Clarke, Javier Víctor, Gerardo Zuniga
    Abstract:

    ABSTRACT Dendroctonus frontalis Zimmermann is considered one of the most important economic and ecological forest pests in the United States, Mexico, and Central America. Recently, two apparent morphological variants of this species were discovered occurring syntopically in Central America and southern Mexico. Morphotype A beetles lack a series of fine parallel ridges on the episternal area of the prothorax that are present on morphotype B. The goal of the present work was to clarify the taxonomic status of the morphotypes of the D. frontalis species complex. Geometric morphometric analyses of seminal rod and spermatheca shape together with the characterization of 16 attributes of external morphology revealed differences in quantitative and qualitative characters that distinguished adults of the two morphotypes from each other as well as from the closely related species Dendroctonus vitei Wood and Dendroctonus mexicanus Hopkins. Karyotype analysis of morphotype B revealed a chromosomal formula (5AA + Xyp)...

  • Southern Pine Beetle, Dendroctonus frontalis, Antennal and Behavioral Responses to Nonhost Leaf and Bark Volatiles
    Journal of Chemical Ecology, 2013
    Co-Authors: William P. Shepherd, Brian T. Sullivan
    Abstract:

    A growing body of evidence suggests that bark beetles detect and avoid release points of volatile compounds associated with nonhost species, and thus such nonhost volatiles may have potential utility in the management of bark beetles. We used a coupled gas chromatograph-electroantennographic detector (GC-EAD) to assay the olfactory sensitivity of the southern pine beetle, Dendroctonus frontalis Zimmermann, to volatiles from leaves and bark of eight species of nonhost angiosperm trees that are common in the range of D . frontalis . Tree species sampled were red maple ( Acer rubrum L.), mockernut hickory [ Carya alba (L.) Nutt. ex Ell.], sweetgum ( Liquidambar styraciflua L.), black tupelo ( Nyssa sylvatica Marsh.), black cherry ( Prunus serotina Ehrh.), southern red oak ( Quercus falcata Michx.), blackjack oak [ Quercus marilandica (L.) Muenchh.], and water oak ( Quercus nigra L.). Beetle antennae responded to a total of 28 identifiable compounds in these samples. The relative olfactory responsiveness to 14 of these, as well as to nonanoic acid and four additional volatiles reported to be associated with nonhost angiosperms, was assessed in GC-EAD analyses of synthetic dilutions spanning six orders of magnitude. The largest response voltage amplitudes were obtained with trans -conophthorin, nonanoic acid, terpinen-4-ol, phenylethyl alcohol, and eucalyptol, whereas the lowest response thresholds were to nonanoic acid, nonanal, linalool, ( E )-2-hexen-1-ol, and phenylethyl alcohol. Funnel traps baited with various combinations of eleven antennally-active angiosperm volatiles along with a standard attractant captured significantly fewer male and female D . frontalis than traps baited with the standard attractant alone. Our data suggest that a diversity of semiochemicals may be involved in host species discrimination by D . frontalis , and several may have utility in their management.

John C Moser - One of the best experts on this subject based on the ideXlab platform.

  • the mexican pine beetle Dendroctonus mexicanus first record in the united states and co occurrence with the southern pine beetle Dendroctonus frontalis coleoptera scolytidae or curculionidae scolytinae
    Entomological News, 2005
    Co-Authors: John C Moser, Bobbe A Fitzgibbon, Kier D. Klepzig
    Abstract:

    2 ABSTRACT: The Mexican pine beetle (XPB) Dendroctonus mexicanus, is recorded here for the first time as a new introduction for the United States (US). Individuals of XPB and its sibling species, the southern pine beetle (SPB) Dendroctonus frontalis, were found infesting the same logs of Chihuahua pine, Pinus leiophylla var. chihuahuana and those of several other pine species in the Chiricahua Mountains, AZ. Both species were also captured in Lindgren traps baited with southern- and western pine beetle attractants, both of which contained the pheromone frontalin. XPB outnum- bered SPB 16:1 in the traps. Both XPB and SPB were trapped during warm periods in winter. It is possible that XPB attack trees during winter as SPB do in the southeastern US. Both XPB and SPB are highly destructive to pines, and XPB could pose a threat if accidentally introduced to pines in the higher elevations of the eastern US.

  • strong indirect interactions of tarsonemus mites acarina tarsonemidae and Dendroctonus frontalis coleoptera scolytidae
    Oikos, 2003
    Co-Authors: María J. Lombardero, Matthew P Ayres, Richard W Hofstetter, John C Moser, Kier D Lepzig
    Abstract:

    Phoretic mites of bark beetles are classic examples of commensal ectosymbionts. However, many such mites appear to have mutualisms with fungi that could themselves interact with beetles. We tested for indirect effects of phoretic mites on Dendroctonus frontalis, which attacks and kills pine trees in North America. Tarsonemus mites are known to carry ascospores of Ophiostoma minus, which tends to outcompete the mutualistic fungi carried by D. frontalis. Experimental additions and removals of mites from beetles demonstrated that Tarsonemus propagate O. minus in beetle oviposition galleries. Furthermore, the abundance of Tarsonemus and O. minus tended to covary in nature. These results verified a strong mutualism between Tarsonemus and O. minus. Results also indicated that O. minus is an antagonist of D. frontalis: beetle larvae seldom survived in the presence of O. minus (compared to 83% survival elsewhere). Apparently, this is an indirect result of O. minus outcompeting the two species of mycangial fungi that are critical to beetle nutrition. Thus, Tarsonemus mites close a loop of species interactions that includes a commensalism (mites and beetles), a mutualism (mites and O. minus), asymmetric competition (O. minus and mycangial fungi), and another mutualism (mycangial fungi and beetles). This interaction system produces negative feedback that could contribute to the endogenous population dynamics of D. frontalis. Reproductive rate of Tarsonemus was more temperature-sensitive than beetle generation time (which constrains the time for mite reproduction within a tree). This differential temperature sensitivity produces a narrow range of temperatures (centred at 27°C) in which mite reproduction per D. frontalis generation can attain its maximum of 100 mites/beetle. Consequently, seasonal oscillations in temperature are predicted to produce oscillations in the D. frontalis community, and climatic differences between regions could influence the community to dampen or exacerbate the cyclical outbreak dynamics of D. frontalis.

  • Tarsonemid mite associates of Dendroctonus frontalis (Coleoptera: Scolytidae): implications for the historical biogeography of D. frontalis
    The Canadian Entomologist, 2000
    Co-Authors: John C Moser, Jorge E. Macias-samano
    Abstract:

    The Canadian Entomologist 132: 765 - 771 (2000) Seven species of mites (Atari: Tarsenomidae) were associated with two local outbreaks of the southern pine beetle, Dendroctonus frontalis Zimmerman, in Chiapas, Mexico; three of these species were new records for Mexico and Central America. The morphology and phoretic behavior of these mites differed little between the western and southern populations from the United States. One major difference was that the hyperphoretic ascospores of the southern pine beetle mycangial fungus, Ceratocystiopsis sp. (Ophiostomataceae), were common in sporothecae of Tarsonemus krantzi Smiley and Moser (Atari: Tarsonemidae) and Tarsonemus ips Lindquist in Chiapas, Mexico, whereas the ascospores of the blue stain fungus, Ophiostoma minus (Hedgcock) H. and P. Sydow (Ophiostomataceae), were rare; this situation in the southern United States is reversed. The paucity of behavioral and morphological differences between the two southern pine beetle populations and the relevant historical climatology suggest that the appearance of D. frontalis in the southern United States may be a recent event. Moser JC, Macias-Sgmano JE. 2000. Acariens tarsonemides associes B Dendroctonus frontalis

  • Biology, demography and community interactions of Tarsonemus (Acarina: tarsonemidae) mites phoretic on Dendroctonus frontalis (Coleoptera: Scolytidae)
    Agricultural and Forest Entomology, 2000
    Co-Authors: María J. Lombardero, Kier D. Klepzig, John C Moser, Matthew P Ayres
    Abstract:

    1- Dendroctonus frontalis, the southern pine beetle, is associated with a diverse community of fungi and mites that are phoretic on the adult beetles. Tarsonemus ips, T. kranzti and T. fusarii (Acarina: Tarsonemidae) may interact within this community in ways that link the population dynamics of D. frontalis, the mites and three dominant species of fungi. We explored species associations by comparing the dietary suitability of different fungi for Tarsonemus spp. 2 - All three mite species fed and reproduced at high rates when feeding on the bluestain fungus, Ophiostoma minus, which is an antagonist of D. frontalis larvae. 3 - Mites also had positive population growth rates when feeding upon Ceratocystiopsis ranaculosus, one of the mycangial fungi, but could barely reproduce when feeding upon Entomocorticium sp. A, the mycangial fungus that is most suitable for D. frontalis. 4 - During the time from colonization of a tree by D. frontalis adults until departure from the tree of their progeny (approximately equal to 40 d at 30 °C), mite pulations feeding upon O. minus can increase by factors of up to 209 (T. fusarii), 173 (T. ips) or 384 (T. krantzi). These high growth rates are allowed by rapid development (age of first reproduction = 8-9 d), high fecundity (approximately equal to 1 egg/d) and high longevity (> 28 d). 5 - Precocious mating increases the chance that females are mated prior to colonizing a new tree and arrhenotokous parthenogenesis permits reproduction by unmated females. 6 - Tarsonemus mites may introduce negative feedback into D. frontalis population dynamics by generating indirect interactions between D. frontalis and O. minus.

Fred M. Stephen - One of the best experts on this subject based on the ideXlab platform.

  • Incidence of honeydew in southern pine-hardwood forests: implications for adult parasitoids of the Southern Pine Beetle, Dendroctonus frontalis (Coleoptera: Scolytidae)
    Biocontrol Science and Technology, 2008
    Co-Authors: Sherah L. Vanlaerhoven, Fred M. Stephen
    Abstract:

    The incidence of homopteran honeydew was measured under pines and hardwoods located within 10 Dendroctonus frontalis Zimmermann infestations on the Talladega National Forest (Alabama) during summer, 2000. There were more honeydew droplets beneath hardwood trees compared to pines, but no difference beween D. frontalis infested and uninfested pines. The number of honeydew droplets per tree differed between sampling dates, likely due to the effect of mean weekly temperature and rainfall on homopteran populations. The presence of honeydew on hardwoods may explain why D. frontalis parasitoids forage in areas that lack hosts and suggests that the fecundity of D. frontalis parasitoids may not be limited by adult nutrition.

  • Adult parasitoids of the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae), feed on artificial diet on pine boles, pine canopy foliage and understory hardwood foliage
    Biocontrol Science and Technology, 2005
    Co-Authors: Sherah L. Vanlaerhoven, Fred M. Stephen, Lloyd E. Browne
    Abstract:

    Abstract This study examined adult parasitoids of Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae) utilizing an artificial parasitoid food on locations with and without hosts. Eliminade™ was applied to bark on boles of infested pines, to pine canopy foliage and to understory hardwood foliage. Adult parasitoids were collected, identified and dissected to determine the presence of Eliminade™ within their guts. Individuals from eight parasitoid species were collected on pine boles within D. frontalis infestations in the Talladega National Forest (Alabama) in the summer of 1999 and 2000. Mean percentage of parasitoids feeding on Eliminade™ was 62±10% during both summers. Percentage of parasitoids feeding was the same 24 h after Eliminade™ application, regardless of food location or parasitoid species. Seven days later, level of parasitoid feeding on Eliminade™ was insignificant in the pine canopy and hardwood understory. In contrast, percent of parasitoid feeding on Eliminade™ applied to pine boles ...

  • partial age specific life tables for monochamus titillator in Dendroctonus frontalis infested loblolly pines
    Entomologia Experimentalis Et Applicata, 2000
    Co-Authors: Kevin J. Dodds, Fred M. Stephen
    Abstract:

    Partial age-specific life tables were constructed for Monochamus titillator (Fabricius) (Coleoptera: Cerambycidae) in Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae) infested loblolly pine (Pinus taeda L.) trees. Successive life stages including egg, early larvae, mid-stage larvae, late larvae, and adult emergence were sampled within six sample trees. Generation mortality ranged from 60.94% to 98.61% in sample trees. Highest mortality typically occurred to eggs and mid-stage larvae. Possible mortality factors included resinosis, predaceous beetles, parasitoids, and woodpeckers. Dendroctonus frontalis brood stages were determined for consecutive M. titillator sampling. Monochamus titillator and D. frontalis coexisted and likely interacted in the phloem of host trees for at least 20 days.

  • Partial age‐specific life tables for Monochamus titillator in Dendroctonus frontalis infested loblolly pines
    Entomologia Experimentalis et Applicata, 2000
    Co-Authors: Kevin J. Dodds, Fred M. Stephen
    Abstract:

    Partial age-specific life tables were constructed for Monochamus titillator (Fabricius) (Coleoptera: Cerambycidae) in Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae) infested loblolly pine (Pinus taeda L.) trees. Successive life stages including egg, early larvae, mid-stage larvae, late larvae, and adult emergence were sampled within six sample trees. Generation mortality ranged from 60.94% to 98.61% in sample trees. Highest mortality typically occurred to eggs and mid-stage larvae. Possible mortality factors included resinosis, predaceous beetles, parasitoids, and woodpeckers. Dendroctonus frontalis brood stages were determined for consecutive M. titillator sampling. Monochamus titillator and D. frontalis coexisted and likely interacted in the phloem of host trees for at least 20 days.

  • APPLICATION OF ELIMINADE™ PARASITOID FOOD TO BOLES AND CROWNS OF PINES (PINACEAE) INFESTED WITH Dendroctonus frontalis (COLEOPTERA: SCOLYTIDAE)
    The Canadian Entomologist, 2000
    Co-Authors: Fred M. Stephen, Lloyd E. Browne
    Abstract:

    The southern pine beetle, Dendroctonus frontalis Zimmermann, is native to pine forests of the southern United States. We describe here techniques for enhancing parasitoid efficacy by direct feeding of parasitoid adults. Our recent research suggests that feeding by female adult D. frontalis parasitoids is important for increased longevity (Mathews and Stephen 1997, 1999; Stephen et al. 1997), and we documented that, with parasitoid feeding, egg resorption decreases and development of new immature eggs increases (Hanano 1996). We suspect that food for D. frontalis parasitoids, in the form of nectar, pollen, or honeydew, is not always available in the forest. We are developing a commercial D. frontalis control strategy based on this assumption.