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The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is a major destructive pest of Pinus L. In the southeastern United States, numbers of this species and a major predator, Thanasimus dubius (Fabricius) (Coleoptera: Cleridae), captured during an annual springtime trapping survey are used to make forecasts of the likelihood and severity of an outbreak during the following summer. We investigated responses by both species to six lure formulations to evaluate their suitability for the survey and allow integration of historical data sets produced with differing lure compositions. Trapping trials were performed at four locations across three states (Louisiana, Mississippi, and Alabama) during spring, and at these and one additional location (North Carolina) in fall 2016. All lures included the pheromone component frontalin. Southern pine beetle preferred lures that additionally included the pheromone component endo-brevicomin and turpentine as a source of host odors (rather than a 7:3 mixture of monoterpenes alpha- and beta-pinene). Thanasimus dubius displayed little discrimination among lure compositions. Lure preferences by southern pine beetle did not differ significantly among locations in spring but were influenced by season. Gas chromatography (GC)-electroantennographic detection analyses with southern pine beetle and GC-mass spectrometry identified numerous known and potential semiochemicals that distinguished volatiles released by the tested host odor devices. The lure combination that included endo-brevicomin and alpha/beta-pinene is recommended for the trapping survey because of its high sensitivity for southern pine beetle and potential for greater data integrity resulting from its reproducible composition.

The southern pine beetle,Dendroctonus frontalisZimmermann (Coleoptera: Curculionidae: Scolytinae), is among the most destructive bark beetle pests of pines (Pinaceae) of the southeast and mid-Atlantic United States of America, Mexico, and Central America. Numerous volatile compounds can stimulate or reduce attraction of the beetle, but efforts to incorporate these into effective, practical technologies for pest management have yielded mixed results. Attractants have been incorporated into lures used in monitoring traps that are employed operationally to forecast outbreaks and detect emerging populations. The attraction inhibitor, verbenone, shows efficacy for suppressing southern pine beetle infestations but has not yet been adopted operationally. No effective semiochemical tree protectant has been developed for the beetle. We discuss complexities in the chemical ecology of the beetle that likely have impeded research and development of semiochemical management tools, and we describe basic science gaps that may hinder further progress if not addressed. We also report some supporting, original experimental data indicating (1) that a verbenone device can inhibit the beetle’s response to sources of attractant in a radius of at least several metres, (2) similar olfactory responses by the beetle to both enantiomers of verbenone, and (3) that pheromone background can cause conflicting results in semiochemical field tests.

The southern pine beetle (SPB) Dendroctonus frontalis Zimmermann, is the most important insect pest of pines in the southeastern United States, with outbreaks often resulting in thousands of hectares of pine mortality. Natural enemies and competitors have been cited as significant regulators of SPB populations and, therefore, outbreaks. A recent outbreak on the Homochitto National Forest (NF) in Mississippi provided an opportunity to undertake a case study comparing population fluctuations of SPB, its major predator Thanasimus dubius, and its competitors, Ips bark beetles. Trap catches of all three were tracked through the course of the outbreak on the Homochitto NF as well as in two other forests with low or no SPB activity. The number of predators collected initially increased on the Homochitto NF in response to the SPB outbreak, but their impact on reducing infestation numbers was unclear. Numbers of Ips trapped were similar across all three forests, indicating that other factors were regulating SPB populations. The outbreak only lasted a single year, and its brevity likely limited the availability of host resources for natural enemy and competitor populations. Additional studies are warranted to explore the mechanisms affecting the extent and duration of SPB outbreaks, such as active forest management.

Climate change is associated with increases in temperature and the frequency and intensity of abiotic disturbances such as drought that can affect forest resilience at multiple scales. Higher temperatures leading to extended growing seasons alter the phenology, distribution, and population dynamics of herbivorous insects. Bark beetles (Coleoptera: Curculionidae: Scolytinae) are among the most ecologically and economically important herbivorous insect taxa and can undergo population eruptions and cause widespread coniferous tree mortality. Specifically, Ips bark beetles preferentially attack conifers that are stressed, dying, or dead—such tree conditions are predicted to become more common due to climate change. Our chapter objectives were to synthesize knowledge on the effects of drought on (1) the incidence of Ips beetle outbreaks and (2) changes in conifer host physiology that increase their susceptibility to bark beetles. We documented 132 Ips beetle outbreaks globally between 1919 and 2018 that were reported in association with drought or water stress. However, very few studies quantitatively demonstrated this relationship and/or defined the mechanisms using experiments. Alterations in host physiology that lead to tree stress will increase colonization by Ips beetles, but their responses may be dependent on attributes at the tree, stand to landscape level. Given the shifts in precipitation and temperature regimes worldwide, we argue for more in-depth studies that quantify the damage and drivers of Ips beetle outbreaks, assessing simultaneous changes in host trees and Ips beetles, ways to mitigate damage for beetle outbreaks, and urgently needed proactive adaptive management strategies in drought-prone forests worldwide.

Since 1987, as many as 16 southeastern US states participate in a 4 wk annual spring Dendroctonus frontalis (Zimmerman) (Coleoptera: Curculionidae) trapping survey. The purpose of the survey is to assess the current D. frontalis outbreak potential, and anticipate prevention and suppression needs for the coming yr. This prediction system relies on capturing the peak D. frontalis spring dispersal, thus timing of trap deployment is crucial. Forest managers traditionally attempt to deploy traps at the onset of flowering dogwood (Cornus florida L.; Cornaceae) bloom, which is commonly assumed to coincide with peak D. frontalis spring dispersal. The objective of this study is to examine the validity of dogwood bloom as an indicator of peak D. frontalis spring dispersal. Yr-round trapping data in 2014 and 2015 from Mississippi and Florida were used to identify peak D. frontalis and Thanasimus dubius (Fabricius) (Coleoptera: Cleridae) dispersal periods. Peak D. frontalis dispersal then was compared with dogwood blooming dates from the USA National Phenology Network and personal records. Then, both dogwood bloom dates and peak D. frontalis dispersal were compared with timing of actual historic state D. frontalis trapping efforts. We also compared peak D. frontalis dispersal with T. dubius peak dispersal, because T. dubius trap captures are used in the prediction model. Last, we examined the utility of extending the spring survey to 6 wk by comparing the 4 wk peak D. frontalis trap captures with a corresponding 6 wk peak. On average, mean onset of dogwood bloom occurred 3 wk after the peak 4 wk period of D. frontalis flight activity. The average T. dubius peak dispersal occurred 1.5 wk after peak D. frontalis dispersal. The 6 wk extension provided only a 12% overall average increase in D. frontalis trap captures. Eastern redbud (Cercis canadensis L.; Fabaceae) also had been suggested as a replacement trap deployment cue; therefore, eastern redbud and flowering dogwood blooming dates in 2019 were monitored on a Mississippi State University property in Oktibbeha County, Mississippi, USA. On this site eastern redbud trees bloomed on average 2.3 wk before the average bloom date of flowering dogwood trees. Resumen Desde el 1987, hasta 16 de los estados del sureste de los Estados Unidos han participado en un sondeo anual de captura de Dendroctonus frontalis (Zimmerman) (Coleoptera: Curculionidae) por 4 semanas en la primavera. El proposito del sondeo es evaluar el potencial actual de brote de D. frontalis y anticipar las necesidades de prevencion y supresion para el proximo ano. Este sistema de prediccion se basa en capturar el pico de dispersion de D. frontalis en la primavera, por lo que el momento del despliegue de la trampa es crucial. Los administradores forestales tradicionalmente intentan desplegar trampas al inicio de la floracion del cornejo (Cornus florida L.; Cornaceae), que comunmente se supone que coincide con el pico de dispersion de D. frontalis en la primavera. El objetivo de este estudio es examinar la validez de la floracion del cornejo como indicador del pico de dispersion de D. frontalis en la primavera. Se utilizaron datos de captura de todo el ano en el 2014 y 2015 de Mississippi y Florida para identificar los periodos de pico de dispersion de D. frontalis y Thanasimus dubius (Fabricius) (Coleoptera: Cleridae). Luego, se comparo el pico de dispersion de D. frontalis con las fechas de floracion del cornejo de la Red Nacional de Fenologia de EE.UU. y los registros personales. Luego, se compararon las fechas de floracion del cornejo y la dispersion maxima de D. frontalis con el cronometraje del estado historico real de los esfuerzos de captura de D. frontalis. Tambien, comparamos el pico de dispersion de D. frontalis con el pico de dispersion de T. dubius, porque las capturas de trampa de T. dubius se utilizan en el modelo de prediccion. Por ultimo, examinamos la utilidad de extender el sondeo de la primavera a 6 semanas comparando los picos de las capturas de trampa de D. frontalis de 4 semanas con los picos correspondientes de 6 semanas. Por general, el inicio de la floracion del cornejo empieza 3 semanas despues del pico de periodo de 4 semanas de actividad de vuelo de D. frontalis. El promedio del pico de dispersion de T. dubius ocurrio 1.5 semanas despues del pico de dispersion de D. frontalis. La extension de 6 semanas proporciono solo un aumento promedio general del 12% en las capturas de trampas de D. frontalis. Tambien, se habia sugerido el ciclamor de Canada (Cercis canadensis L.; Fabaceae) como senal para desplegar el reemplazo de la trampa; por lo tanto, las fechas de floracion de ciclamor de Canada y cornejo en floracion en el 2019 se monitorearon en una propiedad de la Universidad Estatal de Mississippi en el condado de Oktibbeha, Mississippi, EE. UU. En este sitio, los arboles de ciclamor de Canada florecieron en un promedio de 2.3 semanas antes de la fecha promedio de floracion de los arboles de cornejo. Key Words: bloom; Cercis canadensis; Cornus florida; Dendroctonus frontalis; monitoring View this article in BioOne

Cut-and-remove has been the recommended suppression technique for the suppression of infestations of the southern pine beetle (SPB), Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae), with cut-and-leave applied when conditions prevent removal of the felled pines. Changes in forest management practices and the timber industry, plus the expansion of SPB northward have led to an increased reliance on cut-and-leave in recent years. This change has resulted in an exploration of methods to improve the efficacy of cut-and-leave and the development of new tactics for suppressing SPB infestations. We describe these revised and new techniques and discuss their potential applications given current forest management conditions.

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) distinct from that found in morphotype A previously reported for D. frontalis (7AA + Xyp). In the laboratory, forced intermorphotype crosses produced F1 progeny but at lower frequency than intramorphotype pairings, and dissections of spermatheca revealed a lower frequency of insemination at least one type of heterotypic cross. Phylogenetic analysis of the D. frontalis species complex based on 786 bp of the cytochrome oxidase I gene indicated that morphotypes B and A are two independent groups with 98% nodal support within D. frontalis. These data provide compelling evidence that the two syntopic morphotypes represent two distinct sibling species.

The mealybug, Oracella acuta Lobdell, is native to southern USA. It was unintentionally introduced to Guangdong Province, southern China, in 1988 as a result of the importation of infested scions of slash pine, Pinus elliottii Engelm . Infestations were first detected in 1990, rapidly spreading in P. elliottii plantations throughout Guangdong and inflicting severe damage. The mealybug has damaged or threatened both native and introduced pine species in its invaded range because of the suitability of climate, presence of hosts as well as the lack of effective natural enemies. In this paper, we review the current literature and government reports and data to summarize the history, present status and ecology of the species. We then analyze the potential O. acuta invasion in Asia. Available studies are mostly centered on the invasion timing and pathway of this species from USA to China, its current distribution in China, the biological and ecological traits of the species, damage and impacts on forests and ecosystems, and the strategies for its prevention and control. There remain substantial gaps in scientific knowledge of the invasion mechanisms and cost-effective measures for early detection and practical management of O. acuta, including options for biological control . Research on these aspects is required in order to prevent further spread of this pest in China and neighboring countries, and to provide better management in invaded regions.

Technology is being used increasingly in sport to assist, and in some cases replace judges and referees. The photo finish has been used to help the steward decide close horse races for more than a hundred years. In some sports, such as swimming, we have seen adjudication enhanced by electronic timing. In tennis we had the electronic service line machine for many years, and now a device for picking up net cords. More recently, some forms of Rugby have used a video referee to decide on the legality of tries. Cricket followed suit, allowing umpires to refer decisions on run outs, stumpings and catches to a third umpire with access to video footage. In many other sports the media use video replays or other technology (such as the hot spot in cricket) to provide evidence for or against the umpire’s decision.

Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is a major economic pest of pines in the United States, Mexico, and Central America. We report biochemical investigations relevant to the taxonomic status and semiochemistry of two distinct morphotypes of D.frontalis recently detected in the Central American region. Morphotype A beetles (pre-episternal area of prothorax of both sexes smooth, bulging callus on anterolateral margin of prothorax of females) and morphotype B beetles (pre-episternal area of prothorax of both sexes with fine ridges, reduced female callus) collected in infestations in Chiapas, Mexico differed significantly in their production of 10 behaviorally-active compounds occurring in the genus Dendroctonus, including the major pheromone components for D. frontalis. Notably, host-attacking morphotype B females produced hundreds of nanograms of both endo-brevicomin and frontalin, whereas morphotype A females produced similar amounts of frontalin but subnanogram quantities of endo-brevicomin. Reanalysis of a published D. frontalis trapping study in Chiapas indicated that both morphotypes responded in greatest numbers when frontalin and endo-brevicomin baits were both present. In addition, we quantified 18 different cuticular hydrocarbons (the methyl-branched alkane components) from both morphotypes collected in Belize and Chiapas as well as morphotype A beetles from the southeastern United States, and principal component analysis revealed nonoverlapping clusters associated with either morphotype. This evidence of two distinct, complex phenotypes coexisting in the same sites and host trees supports the hypothesis that the D. frontalis morphotypes represent separate species and consequently indicates that the taxonomy of D. frontalis should be re-evaluated in the Central American region.

The southern pine beetle, Dendroctonus frontalis Zimmermann, has three population phases. In the latent phase, southern pine beetle-initiated infestations are absent, and southern pine beetle functions as a secondary bark beetle when present. The outbreak phase results when one or more multi-tree infestations are detected per 1,000 acres of susceptible host type, and the southern pine beetle acts as an aggressive primary colonizer. The intermediate phase consists of population levels between latent and outbreak. The characteristics of these three phases have management implications, and the integrated pest management (IPM) program for the southern pine beetle should be tailored for each phase. Recommendations for each phase are provided and discussed. Prevention and restoration are primary management concerns in the latent phase, whereas suppression takes precedence during an outbreak.

Cricket teams are usually listed on the scoreboard in expected batting order, and although captains can choose to send in any of the remaining batsmen when a wicket falls, they rarely depart from the usual batting order. By optimizing a simplified model using dynamic programming, this paper shows that in all forms of cricket significant increases in expected score result if captains allow a variable batting order and base their decision on the state of the game, rather than using a set batting order.

The mealybug Oracella acuta, native to the southeastern US, was accidentally introduced into slash pine plantations in Guangdong Province in China in 1988. A classical biological control program was initiated in 1995, and the parasitoids Allotropa oracellae, Acerophaus coccois, and Zarhopalus debarri were imported from the US. A total of 19 972 parasitized mealybugs were shipped to China from 1996–2004, from which 15 430 wasps emerged, 12 933 of which were the three target species. Efforts to establish a mass-rearing program for the parasitoids in China failed. Five field release sites were established, and 6 020 parasitoids were released. Only 118 individuals of the three imported species were collected during establishment checks, although several wasps were collected 1–2 years after the last parasitoid release. Over 2 000 Anagyrus dactylopii, a cosmopolitan parasitoid, emerged from the parasitized mealybugs collected, a majority from the Taishan area near the site of the original introduction of O. acuta. To date the imported parasitoids have failed to establish, and natural enemies have not noticeably reduced mealybug populations.

Tomicus yunnanensis Kirkendall and Faccoli (Coleoptera: Curculionidae: Scolytinae) is a newly described pine shoot beetle found in southwestern China. This beetle has affected >200,000 ha of Pinus yunnanensis (Franchet) forests over the past 30 yr. After maturation feeding in the shoots, adults attack the boles in December to produce a new generation. A hanging bolt study was initiated in November 2006 to detect the beetle flight patterns and to test if dispersing beetles respond to infested and uninfested material. Treatments tested were females only, males only, male and female pairs, and uninfested bolts. Beetles were collected on the bolts between 9:30 and 18:30, with peak catch in the afternoon between 14:00 and 18:30. No beetles were collected during the dark. Though trunk attacks in the field were observed in November, beetles were first collected on the bolts in January. No beetles were captured after March. Differences in numbers of beetles collected between treatments with infested bolts varied by month, but uninfested bolts always attracted fewer adults.

Desirable qualities of a tournament are fairness (the better the player, the better his chance of success), balance (few one-sided matches) and efficiency (long enough to benefit the more skillful yet being completed within schedule). The World Professional Snooker Championship is examined to see how well it meets these criteria.

We evaluated the efficacy of systemic insecticides emamectin benzoate and fipronil for preventing mortality of individual loblolly pines, Pinus taeda L., as a result of attacks by southern pine bark beetles (Coleoptera: Curculionidae, Scolytinae) for two consecutive years in Mississippi (2005-2006) and Alabama (2006-2007). Trees were injected once in the spring of 2005 (Mississippi) or 2006 (Alabama) and then were baited with species-specific bark beetle lures several weeks later. The southern pine beetle, Dendroctonus frontalis Zimmermann, was the target species but was changed to Ips spp. in Mississippi (but not Alabama) the second year because of few southern pine beetle attacks on baited trees. Single injections of emamectin benzoate were effective in reducing tree mortality caused by bark beetles compared with untreated checks. Although less effective overall, fipronil also significantly reduced tree mortality from southern pine beetle compared with the checks during the second year in Alabama. Tree mortality continued well after the lures had been removed. Evaluations of bolts taken from experimental trees killed in 2006 indicated that emamectin benzoate effectively prevented parent bark beetle gallery construction and that fipronil significantly reduced lengths of galleries constructed by adult beetles, brood development, and emergence, compared with checks. In contrast, neither insecticide treatment prevented the bark beetles from inoculating blue stain fungi, Ophiostoma spp., into treated trees.

Dendroctonus frontalis Zimmermann (Coleoptera: Scolytinae) is the most serious pest of pines (Pinus spp.) in Mexico. Conspecifics are attracted to trees undergoing colonization by the aggregation pheromone frontalin, which is synergized by odors of pine oleoresin released from beetle-damaged host tissue. Synthetic racemic frontalin combined with turpentine has been the operational bait used in traps for monitoring populations of D. frontalis in Mexico as well as the United States. Recently, racemic endo-brevicomin has been reported to be a synergist of the frontalin/turpentine bait and as an important component of the aggregation pheromone for D. frontalis populations in the United States. To determine whether racemic endo-brevicomin also might function as an aggregation synergist for the geographically isolated D. frontalis populations of Central America and Mexico, we performed a field trapping trial in Lagunas de Montebello National Park, Chiapas, Mexico, during July and August 2007. The combination of endo-brevicomin (placed either directly on the trap or 4 m away) plus racemic frontalin and turpentine caught at least 5 times more D. frontalis of both sexes than did turpentine either alone or in combination with either frontalin or endo-brevicomin. The addition of endo-brevicomin to the frontalin/turpentine bait also increased the proportion of females trapped. We conclude that the addition of endo-brevicomin might substantially improve the efficiency of the frontalin/turpentine bait for monitoring of D. frontalis in Central America and Mexico. We discuss factors that reconcile our results with previous studies that reported endo-brevicomin to be an attractant antagonist for populations of D. frontalis in Mexico and Honduras.

Bark beetle caused mortality continues to play a critical role in determining the composition and structure of forests in North America, and revegetation dynamics following these disturbances are poorly understood. We assessed forest composition following southern pine beetle, Dendroctonus frontalis Zimmermann, mortality and associated cut and leave suppression, and compared them with undisturbed loblolly pine, Pinus taeda L., stands in Texas. Abundant hardwood regeneration dominated the understory, with little loblolly pine regeneration following either mortality event. Disturbances eliminated loblolly pine dominance in these even-aged stands, thus stratifying forest structure and apparently increasing stem density (stems·ha–1), richness (species·ha–1), and diversity (ha) in the lower strata. Aspect and elevation, presumably through influences on site moisture, were the primary gradients associated with vegetation variation in the canonical correspondence analyses for new regeneration. Mortality from Dendroctonus and cut and leave practices shifted loblolly pine communities to mixed upland hardwoods in model predictions generated by the southern variant of the Forest Vegetation Simulator. In addition to being an effective bark beetle control, cut and leave suppression did not alter predicted forest composition 50 years hence when compared with unsuppressed bark beetle-caused mortality. Because of the predicted shift to hardwood domination and a low pine basal area, it is expected that mortality from D. frontalis and cut and leave will substantially reduce future hazards from D. frontalis outbreaks.

Question: Interacting disturbance effects from Dendroctonus frontalis outbreaks and wildfire are thought to maintain Pinus spp. composition in the southeastern U.S. Our objective was to assess forest composition, structure, and succession following the interaction of two frequently occurring disturbance events in southern Pinus spp. forests: cut-and-leave suppression, a commonly used means for managing D. frontalis outbreaks, and wildfire. Location: Western Gulf Coastal Plain, Louisiana, USA. Method: Pinus taeda stands with cut-and-leave suppression and subsequent wildfire were compared to stands undisturbed by D. frontalis but with the same wildfire events twenty years after Pinus spp. mortality. The woody plant community was assessed in three different size classes and used to predict future forest types with the Forest Vegetation Simulator (50 years). Results: P. taeda is the most abundant (> 50%) species of saw- and poletimber-sizes following cut-and-leave suppression with wildfire and in stands only with fire. Using canonical cor respondence analysis, vegetation assemblages were primarily explained by slope position and elevation (7.6% variation explained). Fire intensity and stand age also accounted for variance in the ordination (4.4% and 3.1%, respectively). Dominant and co-dominant P. taeda forest types were predicted by the model to be the most abundant forest types in each disturbance regime. In addition, new regeneration represents high hazard for future mortality from D. frontalis. Conclusion: Our study demonstrates that cut-and-leave suppression with additional wildfire disturbance maintains P. taeda composition, and does not alter forest composition differently from stands receiving only wildfire. As a result, predicted Pinus spp. basal area under both disturbances is great enough to facilitate future bark beetle disturbance.

In cricket, a rain-affected pitch can make batting more difficult than normal. Several other conditions such as poor light or an initially lively pitch, may also result in difficulties for the batsmen. In this note, we refer to all of them as ‘sticky wickets’. On sticky wickets, lower order batsmen are often sent into ‘hold the fort’ until conditions improve. In this paper, a stochastic dynamic programming model is used to examine the appropriateness of this policy. The model suggests that the tactic is often optimal when the sticky wicket persists until the end of the day's play, but not often when the sticky wicket is transitory. In some circumstances, it is worthwhile, on a normal wicket near the end of the day, to send in a lower order batsman to hold the fort (a night watchman): when the wicket is sticky, this tactic is even more worthwhile.

Leaf extracts of the walnut, Juglans regia L., were evaluated under laboratory conditions to determine their acaricidal activity on the mites Tetranychus cinnabarinus (Boisduval) and Tetranychus viennensis Zacher (Acari: Tetranychidae). Extracts had both contact and systemic toxicity to these mites. The four solvents tested for preparing crude extracts were petroleum ether, chloroform, ethyl acetate, and methanol. Methanol was the most efficient solvent, with an extraction rate from 17.06 ± 0.80 to 20.27 ± 0.28%. Petroleum ether was the least effective solvent, with extraction rates from 2.30 ± 0.13 to 2.71 ± 0.13%. However, the crude extracts with petroleum ether resulted in the highest mite mortality (79.04 ± 0.52%) in a slide dip bioassay. Mites mortalities from the concentrated extracts prepared by chloroform, ethyl acetate, methanol, or distilled water were significantly lower than petroleum ether. The mean lethal concentrations (LC50) of the extracts from petroleum ether, chloroform, ethyl acetate, methanol, and distilled water to the two mite species were 0.73 ± 0.04, 1.66 ± 0.28, 4.96 ± 0.35, 7.45 ± 0.67, and 9.91 ± 0.32 mg/ml, respectively. After liquid chromatography and thin-layer chromatography, the concentrated extracts of petroleum ether were separated into eight fractions and tested for acaricidal activity. Fraction 6 produced significantly higher mite mortality rates than the other groups, killing ≈90% of both species.

Extracts of an annual herbaceous plant, Kochia scoparia (L.) Schrad (Macrophomina), were bioassayed to determine their acaricidal activities against Tetranychus urticae Koch, Tetranychus cinnabarinus (Boisduval), and Tetranychus viennensis Zacher (Acari: Tetranychidae) in the laboratory. Extracts had both contact and systemic toxicity to these mites. Three solvents were tested for preparing crude extracts: petroleum ether, chloroform, and methanol. Methanol was the most effective solvent, extracting 3.11–4.53% of the acaricide. Petroleum ether was the least effective solvent, extracting 1.25–1.54%. However, extracts with chloroform resulted in the highest mite mortality (78.86%), and ultrasound-assisted extraction required the least time (10 min). Concentrated extracts were prepared using chloroform, methyl acetate, or distilled water as a solvent. Mite mortalities from the concentrated extracts by methyl acetate or distilled water were significantly lower than those by chloroform. The mean lethal concentrations (LC50) of the extracts by chloroform, methyl acetate, and distilled water to the mites were 0.71 ± 0.06, 2.08 ± 0.16 and 8.75 ± 0.062 mg/ml, respectively. After liquid chromatography and thin layer chromatography, the concentrated extracts by chloroform were separated into seven groups of isolated fractions and tested for acaricidal activity.

The effects of different doses and enantiomers of verbenone on the interruption of response of red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Scolytidae), a very aggressive and destructive exotic pest, were conducted using electoantennogram (EAG) assays and behavioral tests in the laboratory and field. No significant differences were found between antennal responses of D. valens by sex, and only one significant difference occurred between their responses to equivalent doses of the (S)-(−) and (R)-(+) enantiomers.Antennal responses to increased doses of (S)-(−)-verbenone reached a plateau at 0.1 μg, whereas the amplitude of response to increased dosages of (R)-(+)-verbenone continued to rise. In a laboratory bioassay, (S)-(−)-verbenone at a stimulus load of 0.1 μg synergized D. valens response to a kairomone blend; but at higher stimulus loads (10 and 100 μg), it functioned as a repellent. In field trials using funnel traps, both (S)-(−)- and (R)-(+)-verbenone bubblecaps inhibited...

With the growth in sports betting, it is possible to bet, both before and during a match, on a range of outcomes in tennis. This paper shows how the standard statistics published by the ATP can be combined to predict the serving statistics to be obtained when two given players meet. These statistics are then used in a spreadsheet model to predict further match outcomes, such as the length of the match and chance of either player winning. These calculations can be updated as the match progresses. The method is demonstrated by focusing on a very long men’s singles match between Roddick and El Aynaoui played at the 2003 Australian Open.

SummaryMultiple linear regression techniques are applied to determine the relative batting and bowling strengths and a common home advantage for teams playing both innings of international one-day cricket and the first innings of a test-match. It is established that in both forms of the game Australia and South Africa were rated substantially above the other teams. It is also shown that home teams generally enjoyed a significant advantage. Using the relative batting and bowling strengths of teams, together with parameters that are associated with common home advantage, winning the toss and the establishment of a first-innings lead, multinomial logistic regression techniques are applied to explore further how these factors critically affect outcomes of test-matches. It is established that in test cricket a team’s first-innings batting and bowling strength, first-innings lead, batting order and home advantage are strong predictors of a winning match outcome. Contrary to popular opinion, it is found that the team batting second in a test enjoys a significant advantage. Notably, the relative superiority of teams during the fourth innings of a test-match, but not the third innings, is a strong predictor of a winning outcome. There is no evidence to suggest that teams generally gained a winning advantage as a result of winning the toss.

The pine-feeding mealybug, Oracella acuta (Lobdell), was accidentally introduced and established in Guangdong Province, China, in 1988 (Sun et al. 1996, J. For. 94: 27-32). It spread rapidly through the extensive plantations of exotic slash pine, Pinus elliottii Englem. var. elliottii, a species native to the U.S. Total volume growth loss has exceeded 33% in some cases, though tree mortality has not been reported (Ren et al. 2000, Natur. Enemies of Insects 22: 140-143). Oracella acuta is seldom a pest in the U.S. due to an effective natural enemy complex (Clarke et al. 1990, Environ. Entomol. 19: 99-103; Sun et al. 2002, J. Entomoi. Sci. 37: 177-181). Outbreaks occur when natural enemy populations are drastically reduced, particularly by insecticide applications (Clarke et al. 1992, J. Econ. Entomoi. 85: 1246-1252). Sun et al. (2004, J. Entomol Sci 39: 11-22) conducted preliminary studies of the parasitoid complex of 0 . acuta in the U.S. to evaluate the potential for a classical biological control program against the mealybug in China. Two of the predominant parasitoids of 0. acuta were Allotropa n. sp. (Platygastridae) and Zarhopalus debarri Sun (Encyrtidae). Zarhopalus debarri is a solitary endoparasitoid that primarily attacks adult females. Only one egg is deposited per 0. acuta female. Allotropa n. sp. prefers adult females, but will attack second and third instar females. This species is gregarious and often lays multiple eggs in larger hosts. The complete life cycle of both species averages 26 days at 27"C, with the female adult stage averaging 6 days. The abundance of the two species may vary seasonally, annually, or by site. Studies on natural enemies and their host in their native country can provide insight into the nature of the interspecific relationships and help guide the selection of appropriate

The parasitoid complex of the mealybug Oracella acuta (Lobdell) was examined in two field populations in Georgia in 1995–96. Allotropa n. sp. and Zarhopalus debarri Sun were the primary endoparasitoids emerging from O. acuta. Adult abundance varied seasonally, with Allotropa n. sp. numbers peaking in June and Z. debarri in September. Parasitism rates of female O. acuta exceeded 60% at one site and ranged from 24 to 29% at the other site. The adult female was the preferred host stage for parasitism (76%), though Allotropa n. sp. and the endoparasitoid Acerophagus coccois E. Smith occasionally utilized second and third instar females as hosts. These two species exhibited gregarious parasitism, with up to 5 Allotropa n. sp. or 4 A. coccois emerging from a single host. Adult longevity of female and male Z. debarri averaged 6.4 and 5.3 days, respectively, and access to a food source usually increased adult lifespan. Female Z. debarri contained an average of 119 eggs, compared to 74 eggs per female for Allotropa n. sp.

Infestations of the southern pine beetle (SPB) (Dendroctonus frontalis Zimmermann) affected 7,929 ac of managed forest and 13,346 ac of wilderness on the National Forests in Texas (NFT) during the 1990s. Direct control treatments were applied to two-thirds of the 8,486 infestations on managed forest; the average size of treated spots was 1.3 ac. Inactive infestations averaged only 0.25 ac. Cut-and-remove was the preferred treatment; and only one application per infestation was required for over 97% of infestations treated by this method. Cut-and-leave was applied to 27% of infestations requiring treatment; and a single application was effective for 90% of treated infestations. In wilderness, where SPB suppression was limited due to legal constraints, large infestations developed, killing over 40% of the susceptible host type. In contrast, less than 2% of the susceptible host type was killed in nonwilderness areas of the NFT. Economic analyses indicate the SPB suppression program was cost-effective, with an estimated benefit/cost ratio of 3.55:1. South. J. Appl. For. 27(2):122–129.