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Ceracris kiangsu (Orthoptera: Arcypteridae), is greatly affected by climatic factors and exhibits strong adaptability, posing a serious threat to the ecological environment. Therefore, predicting its potential suitable habitat distribution provides a proactive theoretical basis for pest control. This study using the Biomod2 package of R simulated and predicted the current and future potential distribution, area changes, changes in the center points of suitable habitats, and niche shifts of C. kiangsu under two different greenhouse gas emission scenarios, SSP1-26 and SSP5-85. The results show that: (1) Currently, the high suitability areas for C. kiangsu are mainly distributed in Yunnan, Jiangxi, Hunan provinces in southern China and phongsaly province in northern Laos. In the future, the center of the suitable habitat distribution pattern of C. kiangsu will remain unchanged, primarily expanding outward from medium and high suitability areas. Additionally, significant suitable habitats for C. kiangsu were discovered in Southeast Asian countries without previous pest records. (2) Compared to the present, the overall suitable habitat area for C. kiangsu is expected to expand, particularly under the SSP5-85 climate change scenario. (3) In the SSP1-26 and SSP5-85 climate scenarios, the geometric center of the suitable habitat generally shows a trend of gradually shifting northeast. (4) Under different climate scenarios, the suitable habitat of C. kiangsu has highly overlapping, indicating that the suitable habitat of C. kiangsu in the invaded areas is broader than in its native regions. In conclusion, the research findings represent a breakthrough in identifying the potential distribution areas of C. kiangsu, which is of great practical significance for the monitoring and control of C. kiangsu pest infestation in China and Southeast Asian countries. [ABSTRACT FROM AUTHOR]

In 2023, branches of European beech (Fagus sylvatica L.) were placed on 24 different study sites within beech stands in the Czech Republic to study the distribution of the beech bark beetle (Taphrorychus bicolor Her.). After infestation, the branches were placed in emergence traps to capture adults of the offspring generation. In total, 2167 adults of T. bicolor were captured across the 24 study sites. The average capture (mean ± SE) was 90.3 ± 24.4 adults per site. Statistical analyses, including GLMM and GLM, were employed to assess the influence of elevation and stand age on the abundance of T. bicolor. The results indicate that the distribution of T. bicolor is mainly influenced by the elevation and age of the beech stand. The number of captured adults decreased with elevation and increased with stand age. Climatic region, volumes of beech, and volumes of felled beech wood from principal felling and thinning felling had no significant effect on the number of T. bicolor adults captured. We found that, overall, 73.37% of Czech beech stands (at elevations 300–650 m a.s.l.) are possibly threatened (either highly or slightly) by the large occurrence of T. bicolor, because they are present at elevations where T. bicolor is widespread. No outbreaks of T. bicolor have yet been reported in the Czech Republic, but with the increasing amount of beech planted, combined with global climate change, the possibility of outbreaks in the future cannot be excluded. [ABSTRACT FROM AUTHOR]

The invasive poplar leaf miner Leucoptera sinuella (Lepidoptera: Lyonetiidae), has spread throughout poplar plantations in central Chile. We developed and validated models based on two methodologies of foliar damage estimation, and from different bands and indexes obtained from Sentinel-2 satellite images. We estimated foliar damage with field visual application of an ordinal severity scale, or with a laboratory estimation of leaf mined area with an image software (ImageJ) from a sample of leaves using an ordinal severity scale. We developed four models for the visual estimation on the field using red band and three spectral indexes, while we developed four models for the laboratory image software estimation using near infrared (NIR) band and the same three spectral indexes. Models developed from field visual estimation with red band (R2 = 0.88) and Normalized Difference Vegetation Index (NDVI) (R2 = 0.89) produced better results, as well as from image software estimation with NIR band (R2 = 0.86) and NDVI (R2 = 0.83). The field visual estimation and red band model got the best validation results, with R2 of 0.90, mean square error of 0.73, mean absolute error of 0.59, and a slope of 0.91. This model could predict the severity of foliar damage by L. sinuella in poplar plantations, representing a potentially useful monitoring tool for decision-making in the management of the poplar leaf miner in large areas of poplar plantations in central Chile. [ABSTRACT FROM AUTHOR]

Abstract Ceracris kiangsu (Orthoptera: Arcypteridae), is greatly affected by climatic factors and exhibits strong adaptability, posing a serious threat to the ecological environment. Therefore, predicting its potential suitable habitat distribution provides a proactive theoretical basis for pest control. This study using the Biomod2 package of R simulated and predicted the current and future potential distribution, area changes, changes in the center points of suitable habitats, and niche shifts of C. kiangsu under two different greenhouse gas emission scenarios, SSP1-26 and SSP5-85. The results show that: (1) Currently, the high suitability areas for C. kiangsu are mainly distributed in Yunnan, Jiangxi, Hunan provinces in southern China and phongsaly province in northern Laos. In the future, the center of the suitable habitat distribution pattern of C. kiangsu will remain unchanged, primarily expanding outward from medium and high suitability areas. Additionally, significant suitable habitats for C. kiangsu were discovered in Southeast Asian countries without previous pest records. (2) Compared to the present, the overall suitable habitat area for C. kiangsu is expected to expand, particularly under the SSP5-85 climate change scenario. (3) In the SSP1-26 and SSP5-85 climate scenarios, the geometric center of the suitable habitat generally shows a trend of gradually shifting northeast. (4) Under different climate scenarios, the suitable habitat of C. kiangsu has highly overlapping, indicating that the suitable habitat of C. kiangsu in the invaded areas is broader than in its native regions. In conclusion, the research findings represent a breakthrough in identifying the potential distribution areas of C. kiangsu, which is of great practical significance for the monitoring and control of C. kiangsu pest infestation in China and Southeast Asian countries.

Sirex noctilio is an invasive forest wasp that affects pines in many parts of the globe and can result in severe economic losses. Current trapping methods for monitoring the pest rely heavily on non‐specific semiochemicals. This lack of specificity can translate into low attraction/capture levels, something that is undesired, especially when the intent is to detect the pest when still at low population densities. In this context, an interesting opportunity arises to increase trap sensitivity by incorporating visual cues. For this, we evaluated potential sources of visual information that, in accordance with the ecology of the species, could elicit an attractive response complementary to the olfactory cues. We measured the reflectance spectra of pine bark, chlorotic needles and woodwasp male abdomens. The spectra were then compared with 120 commercial paint colours to be applied on panel traps. During two flight seasons, field experiments were conducted with the deployment of 155 traps, combining the volatile bait (turpentine) and different coloured traps. We observed a significantly higher number of captures towards traps with pine bark‐like colourations compared with the black control traps. Our results are encouraging, as they suggest the potential of combining visual and chemical information for sustainable pest biomonitoring. [ABSTRACT FROM AUTHOR]

AbstractThe box tree moth (BTM), Cydalima perspectalis, and the fall webworm (FWW), Hyphantria cunea are two invasive forest pests in northern Iran. Entomopathogenic nematodes (EPNs) are usually compatible with integrated pest management programs. In this study, the efficacy of five isolates of EPNs was evaluated against the two pests in laboratory and field conditions. LC50 values of Steinernema carpocapsae (IRTabriz), S. feltiae (IRTabriz), S. feltiae (Entonem), Oscheius rugaoensis and Heterorhabditis bacteriophora (IRTabriz) were as follow: 44.8, 66.5, 113.8, 190.7 and 515.9 infective juveniles (IJs) larva−1 on the fifth instar larvae of BTM; and 75.2, 96.6, 131.0, 258.0 and 292.5 IJs larva−1 on fifth instar larvae of FWW, respectively in the laboratory tests 48 h post-treatment at 25 °C and 60% relative humidity. Under field conditions, the foliar applications of S. carpocapsae (IRTabriz), S. feltiae (IRTabriz), and S. feltiae (Entonem) at the rate of 106 IJs L−1 resulted in 36–58% mortality after 48 h against BTM and 15–52% mortality against FWW, respectively. The results demonstrate that EPNs are promising candidates for biocontrol of BTW and FWW. [ABSTRACT FROM AUTHOR]

The bark beetle Ips typographus (L.) is the most important pest in European Norway spruce forests. Especially after abiotic disturbance events, like storms or snowfall, this beetle can utilise vast amounts of trees with impaired defences, leading to mass outbreaks and further mortality of spruce. In 2018, the 'Vaia' storm damaged huge areas of Norway spruce-dominated forests in the Southern Alps. In the following years, the same regions were additionally affected by heavy snowfalls providing high amounts of suitable material for I. typographus brood establishment and development. Since then, these forests have faced unprecedented population outbreaks of I. typographus with severe effects for forest ecosystems, from both an ecological and an economic perspective. A comprehensive understanding of this beetle's genetic structure, including effects of the last ice ages as well as consequences of current population outbreaks, can give insights into the population dynamics of an eruptive species. Here, we studied the genetic structure of five epidemic populations from the Southern Alps and one from a potential glacial refugium in the Apennines. Our results revealed a low genetic diversity and a weak population structure among all studied locations. In the six analysed populations, four already described haplotypes, belonging to three slightly divergent haplogroups, were found. These haplotypes were evenly distributed among populations, including the potential glacial refugium in the Apennines. High gene flow among populations is probably maintained by the beetle's high dispersal capacity and high population densities, resulting in a panmictic population structure. [ABSTRACT FROM AUTHOR]

The spatial distribution of Dendroctonus frontalis Zimmermann, 1868, and Dendroctonus mexicanus Hopkins, 1905, was determined from 2020 to 2021 in the Tixtlancingo ejido. The information came from two surveys because, despite the abundant forested areas in this geographical area of the state of Guerrero, Mexico, economic resources for pest biomonitoring are limited. However, it was possible to identify the presence of 76 outbreaks affecting 1117.697 hectares and 95,078 trees, totaling 14,223.8 m 3 of standing timber volume. In 2020, 28 outbreaks were reported, with the eastern spatial distribution showing the most damage from bark beetles, particularly in outbreaks 7 and 14 of the surveyed area. The most affected conifers were Pinus maximinoi H. E. Moore (44.71%), Pinus oocarpa Schiede ex Schltdl. (39.93%), and Pinus pseudostrobus Lindl. (15.36%). The affected timber volume was observed in diameter categories of 30 cm for the three pine species, with infestation of 90,549 trees (13,497.6 m 3 t.t.v. (total tree volume)) across 1057.64 hectares. In 2021, 48 outbreaks were recorded, with the northeastern and southern parts of the surveyed area showing the most damage from the bark beetle. The trees most affected by the bark beetle were P. oocarpa (59.17%), P. maximinoi (33.94%), and P. pseudostrobus (6.89%). It was observed that the affected volume occurred in trees with diameter categories of 50 cm for the three pine species, affecting 4529 trees (726.214 m 3 t.t.v.) distributed over 60.06 hectares. The contribution of this work lies in establishing a baseline for monitoring damage caused by this beetle, which affects forest resources and diminishes the possibility of maintaining carbon capture areas in the medium and long term, thus impacting the Sustainable Development Goals (SDGs) of the 2030 agenda, specifically Goals 11, 13, and 15. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In response to the shortcomings of traditional pest detection methods, such as inadequate accuracy and slow detection speeds, a lightweight forestry pest image recognition model based on an improved YOLOv8 architecture is proposed. Initially, given the limited availability of real deep forest pest image data in the wild, data augmentation techniques, including random rotation, translation, and Mosaic, are employed to expand and enhance the dataset. Subsequently, the traditional Conv (convolution) layers in the neck module of YOLOv8 are replaced with lightweight GSConv, and the Slim Neck design paradigm is utilized for reconstruction to reduce computational costs while preserving model accuracy. Furthermore, the CBAM attention mechanism is introduced into the backbone network of YOLOv8 to enhance the feature extraction of crucial information, thereby improving detection accuracy. Finally, WIoU is employed as a replacement for the traditional CIOU to enhance the overall performance of the detector. The experimental results demonstrate that the improved model exhibits a significant advantage in the field of forestry pest detection, achieving precision and recall rates of 98.9% and 97.6%, respectively. This surpasses the performance of the current mainstream network models. [ABSTRACT FROM AUTHOR]

In 2023, branches of European beech (Fagus sylvatica L.) were placed on 24 different study sites within beech stands in the Czech Republic to study the distribution of the beech bark beetle (Taphrorychus bicolor Her.). After infestation, the branches were placed in emergence traps to capture adults of the offspring generation. In total, 2167 adults of T. bicolor were captured across the 24 study sites. The average capture (mean ± SE) was 90.3 ± 24.4 adults per site. Statistical analyses, including GLMM and GLM, were employed to assess the influence of elevation and stand age on the abundance of T. bicolor. The results indicate that the distribution of T. bicolor is mainly influenced by the elevation and age of the beech stand. The number of captured adults decreased with elevation and increased with stand age. Climatic region, volumes of beech, and volumes of felled beech wood from principal felling and thinning felling had no significant effect on the number of T. bicolor adults captured. We found that, overall, 73.37% of Czech beech stands (at elevations 300–650 m a.s.l.) are possibly threatened (either highly or slightly) by the large occurrence of T. bicolor, because they are present at elevations where T. bicolor is widespread. No outbreaks of T. bicolor have yet been reported in the Czech Republic, but with the increasing amount of beech planted, combined with global climate change, the possibility of outbreaks in the future cannot be excluded.

The European spruce bark beetle Ips typographus is a pest causing severe damage in forests dominated by Norway spruce in Europe. Microorganisms play essential roles in bark beetles, including nutrition, fitness as well as in overcoming host defenses. Here, we performed high-throughput 16S rRNA metabarcoding of I. typographus across different populations in Europe, to assess its bacterial community. We investigated four postglacial refugial areas in Europe and focused specifically on a current bark beetle hot spot in the Dolomites where we compared populations with different epidemiological phases (outbreaking vs. non-outbreaking) and across different seasons (pre-overwintering vs. overwintering). Our results show that the bacterial community structure varied among populations from the refugial areas and between different regions within the Dolomites. We found a significant difference in the bacterial community between pre-overwintering and overwintering individuals, but we did not find differences between epidemic and endemic populations. The prevalence of the genera Erwinia (which was present in all individuals) and Pseudoxanthomonas (present in almost all individuals) across all populations suggests that these taxa form the core bacterial community of I. typographus. Furthermore, several additional bacterial taxa occurred in all populations, but with variable frequencies. This study highlights a complex interaction of I. typographus and various bacterial taxa across different regions and ecological phases and provides new insights into the role of microorganisms in the biology of this important pest species. [ABSTRACT FROM AUTHOR]

The egg parasitoid Cleruchoides noackae Lin & Huber, 2007 (Hymenoptera: Mymaridae) is originated from Australia and the main biological control agent of Thaumastocoris peregrinus Carpenter & Dellapé, 2006 (Hemiptera: Thaumastocoridae) on Eucalyptus L'Hér (Myrtaceae). Companies that grow Eucalyptus are in need of a mass rearing protocol to increase the number of individuals produced and improve the quality of this parasitoid. The aim of this study was to define a protocol for mass rearing C. noackae in T. peregrinus eggs, based in the evaluations of the key biological attributes of this parasitoid in the parental and F1 generations, after the cold storage of the parasitised host eggs. Two methods were tested as C. noackae rearing protocols. In the first, parasitised eggs of T. peregrinus by C. noackae were cold stored for 7 days after being left in a climatic chamber at 24 ± 2°C, 60 ± 10% RH and a photoperiod of 12:12 (light:dark) h (standard environmental conditions) for 3, 6, 9 or 12 days. In the second, T. peregrinus eggs parasitised by C. noackae were maintained in a climatic chamber under standard environmental conditions for 6 days, after which these eggs were cold-stored for 0 (control), 7, 14 or 21 days. Parasitism (%), and the development period (parasitism to adult) and female proportion (%) of C. noackae were evaluated. Based on the results (parental generation: parasitism, around 45%; F1 generation: parasitism, around 55%; development period, around 16 days; female proportion, around 60%), eggs should be stored at 5°C on the sixth day after parasitism by C. noackae and maintained at this temperature for 7 days. The cold storage of T. peregrinus eggs, after parasitism, can be included in the mass rearing protocols of the parasitoid C. noackae. [ABSTRACT FROM AUTHOR]

The North American oak lace bug (OLB), Corythucha arcuata, is an invasive species in Europe and a serious threat to oak‐dominated forests.Survival at low temperatures is one major factor determining the spread of invasive insects. Thus, we studied key traits, that is, cold‐tolerance strategy, supercooling points (SCP) and chilling‐related mortality, of overwintering adults to assess their potential to withstand harsh winters.Samples for SCP measurements were collected once a month from November 2020 until March 2021 at three different locations in Hungary; specimens for chilling experiments were sampled in November 2020, January 2021 and March 2021.SCPs of overwintering adults ranged from −29.68 to −7.49 °C, with only moderate variation among months; C. arcuata is a freeze‐avoidant species.Mortality rates of adults exposed to two sub‐zero temperatures above the SCP (−3 and −5 °C) for 1, 2 and 3 weeks ranged between 0% and 69.1%, suggesting that OLB has a moderate risk to die from chilling injuries. Exposure time and sampling date affected mortality, with lowest survival rates after 3 weeks, collected in March 2021. [ABSTRACT FROM AUTHOR]

The spatial distribution of Dendroctonus frontalis Zimmermann, 1868, and Dendroctonus mexicanus Hopkins, 1905, was determined from 2020 to 2021 in the Tixtlancingo ejido. The information came from two surveys because, despite the abundant forested areas in this geographical area of the state of Guerrero, Mexico, economic resources for pest biomonitoring are limited. However, it was possible to identify the presence of 76 outbreaks affecting 1117.697 hectares and 95,078 trees, totaling 14,223.8 m3 of standing timber volume. In 2020, 28 outbreaks were reported, with the eastern spatial distribution showing the most damage from bark beetles, particularly in outbreaks 7 and 14 of the surveyed area. The most affected conifers were Pinus maximinoi H. E. Moore (44.71%), Pinus oocarpa Schiede ex Schltdl. (39.93%), and Pinus pseudostrobus Lindl. (15.36%). The affected timber volume was observed in diameter categories of 30 cm for the three pine species, with infestation of 90,549 trees (13,497.6 m3 t.t.v. (total tree volume)) across 1057.64 hectares. In 2021, 48 outbreaks were recorded, with the northeastern and southern parts of the surveyed area showing the most damage from the bark beetle. The trees most affected by the bark beetle were P. oocarpa (59.17%), P. maximinoi (33.94%), and P. pseudostrobus (6.89%). It was observed that the affected volume occurred in trees with diameter categories of 50 cm for the three pine species, affecting 4529 trees (726.214 m3 t.t.v.) distributed over 60.06 hectares. The contribution of this work lies in establishing a baseline for monitoring damage caused by this beetle, which affects forest resources and diminishes the possibility of maintaining carbon capture areas in the medium and long term, thus impacting the Sustainable Development Goals (SDGs) of the 2030 agenda, specifically Goals 11, 13, and 15.

Eucalyptus snout beetles are a complex of at least eight cryptic species (Curculionidae: Gonipterus scutellatus complex), native to mainland Australia and Tasmania, that defoliate Eucalyptus trees and are considered important pests. Since the 19th century, three species of the complex have been introduced to other continents. Here, we document the presence of Eucalyptus snout beetles in Ecuador. We used DNA data for species identification and unambiguously demonstrated that the Ecuadorian specimens belong to the species Gonipterus platensis, which has low genetic diversity compared with other species in the complex. We analyzed G. platensis' potential distribution in South America with ecological niche models and found several areas of high to intermediate climatic suitability, even in countries where the pest has not been registered, like Peru and Bolivia. Accurate identification of species in the G. scutellatus complex and understanding of their potential distribution are essential tools for improved management and prevention tactics. [ABSTRACT FROM AUTHOR]

The walking-stick insect Ramulus mikado is occasionally considered a forest pest, as its mass occurrence can cause severe defoliation. It overwinters as eggs on the ground surface, and the hatched nymphs climb up to the host trees in spring. In this study, temperature-dependent development experiments were performed on R. mikado eggs under three constant temperatures (23.3, 28.3, and 29.2 °C) to extend the previously reported thermal response. The development times of eggs collected in summer and winter were also compared to investigate how development status is influenced by the seasons. The lower and upper developmental thresholds and thermal constants of R. mikado eggs were estimated to be 6.1 °C, 29.2 °C, and 1707.8 DD, respectively. The starting point for effective temperature effects on the eggs was estimated to be 1 August, based on the results of the experiment on field-collected eggs. A phenology model was constructed by using a development completion model scaled by the thermal constant, with a starting point of degree-day accumulation. The model showed good agreement, with a deviation of 3.2 ± 2.95 days between prediction and observation. The developed phenology model is useful for determining the appropriate timing for management decision-making regarding this insect. [ABSTRACT FROM AUTHOR]

The leaf-cutting ant Acromyrmex crassispinus is considered an important pest in forest plantations in southern Brazil. This work aimed to study the fungal community associated with A. crassispinus colonies, subjected to treatments with subdoses of granulated baits (sulfluramid), which might reduce the ability of the ants to care for their symbiotic fungus and other fungi (maybe biocontrol fungi) would take over, to prospect for potential biological control agents. Samplings of fungus gardens and dead ants allowed the identification of 195 fungal isolates, distributed in 29 families, 36 genera, and 53 species. The most frequent genera were Trichoderma (49.2%), Penicillium (13.8%), Chaetomium (6.2%), and Fusarium (3.6%). This is the first study that conducted a survey of antagonistic and entomopathogenic fungi to A. crassispinus and its symbiotic fungus, reporting for the first time the occurrence of potential biological control agents. Escovopsis weberi, Fusarium oxysporum, Rhizomucor variabilis, Trichoderma atroviride, Trichoderma harzianum, Trichoderma koningiopsis, and Trichoderma spirale are considered some of the potential biocontrol organisms. [ABSTRACT FROM AUTHOR]

The nymphs and adults of champ bug, Urostylis parapunctigera Yang (Hemiptera: Urostylididae) were observed damaging Magnolia champaca trees at Umiam, Meghalaya State of northeast India. This bug species was previously described in 1938 from a male collected from Jalpaiguri, West Bengal, India during 1931 and preserved in the British Museum. Apart from this, no further information is available regarding this species. Morphologically and by nature of damage, U. parapunctigera is very similar to another important destructive pest, U. punctigera Westwood, co-occurring on similar host plants in northeast India, and thus it might have been ignored because of confusion with U. punctigera. The present study is the first photographically illustrated redescription of male and female of U. parapunctigera. Also, this study provides key diagnostic characters of U. parapunctigera, which distinguish it from the more common U. punctigera, [ABSTRACT FROM AUTHOR]

In response to the shortcomings of traditional pest detection methods, such as inadequate accuracy and slow detection speeds, a lightweight forestry pest image recognition model based on an improved YOLOv8 architecture is proposed. Initially, given the limited availability of real deep forest pest image data in the wild, data augmentation techniques, including random rotation, translation, and Mosaic, are employed to expand and enhance the dataset. Subsequently, the traditional Conv (convolution) layers in the neck module of YOLOv8 are replaced with lightweight GSConv, and the Slim Neck design paradigm is utilized for reconstruction to reduce computational costs while preserving model accuracy. Furthermore, the CBAM attention mechanism is introduced into the backbone network of YOLOv8 to enhance the feature extraction of crucial information, thereby improving detection accuracy. Finally, WIoU is employed as a replacement for the traditional CIOU to enhance the overall performance of the detector. The experimental results demonstrate that the improved model exhibits a significant advantage in the field of forestry pest detection, achieving precision and recall rates of 98.9% and 97.6%, respectively. This surpasses the performance of the current mainstream network models.

Abstract Eucalyptus snout beetles are a complex of at least eight cryptic species (Curculionidae: Gonipterus scutellatus complex), native to mainland Australia and Tasmania, that defoliate Eucalyptus trees and are considered important pests. Since the 19th century, three species of the complex have been introduced to other continents. Here, we document the presence of Eucalyptus snout beetles in Ecuador. We used DNA data for species identification and unambiguously demonstrated that the Ecuadorian specimens belong to the species Gonipterus platensis, which has low genetic diversity compared with other species in the complex. We analyzed G. platensis' potential distribution in South America with ecological niche models and found several areas of high to intermediate climatic suitability, even in countries where the pest has not been registered, like Peru and Bolivia. Accurate identification of species in the G. scutellatus complex and understanding of their potential distribution are essential tools for improved management and prevention tactics.

The effects of different defoliation levels caused by leaf-cutting ants have not yet been evaluated in Eucalyptus benthammii Maiden et Cambage and Eucalyptus dunnii Maiden plants. The aim of this study was to evaluate the losses caused by different defoliation levels on E. benthammii and E. dunnii plants artificially defoliated 30 days after planting, simulating Acromyrmex attacks. Four treatments were evaluated: 0: control, 1: 50%, 2: 75%, and 3, 100% defoliation. Plant height and diameter were recorded at 6, 12, 24, 36 and 72 months after planting. At six months, height and diameter of E. bentammii plants subjected to 100% defoliation differed significantly from control plants, however no significant differences in plant height and diameter were seen after 12 months. In E. dunnii, 100% defoliation resulted in significant plant mortality, and plants that survive this level of defoliation had significant losses in their development. In case of Acromyrmex attack on eucalyptus plants at 30 days after planting, it is suggested to replant E. dunnii 100% defoliated to avoid losses in the end of the forest cycle. In E. benthammii plantations, it is suggested to evaluate the vigor of the 100% defoliated seedlings, as they can recover over time. Only 100% defoliation can lead to losses in Eucalyptus plant growth. However, regionalized studies are necessary to assess the losses that intense defoliation can cause in each situation and in each plant species, as some species, such as E. benthammii, can recover along time. [ABSTRACT FROM AUTHOR]

Aeolesthes sarta or Trirachys sarta is a polyphagous long-horned beetle that has caused severe damage to the Populus alba forests/plantations in its regions of origin. Climate change could accelerate the introduction and spread of invasive pest species, potentially causing ecological damage and economic losses. Furthermore, globalization and increased trade can inadvertently transport pests across borders into regions where they do not already occur. Hence, it is crucial to identify areas where the climate is most suitable for the establishment of A. sarta's and which areas of the world are suitable for the growth of P. alba under climate change scenarios. This study employed the CLIMEX model to estimate the potential global distribution of A. sarta and its correlation with its dominant host, P. alba, under current climatic conditions and potential future scenarios, namely the A1B and A2 climate change scenarios (CCSs). Under current climatic conditions, the model indicates that the establishment of a climatically suitable habitat for A. sarta extends beyond its current known range. The model estimated that, under the world's current climatic conditions, 41.06% of the world can provide suitable areas (EI > 0) for the survival of A. sarta. For P. alba, under the current climatic conditions, suitable regions for the growth of P. alba are present in all continents (excluding Antarctica); under the world's current climatic conditions, 53.52% of the world can provide suitable areas for the growth of P. alba (EI > 0). Climate change will significantly alter the number of suitable habitats for A. sarta development and P. alba growth globally. In future climatic conditions, the number areas capable of supplying suitable habitats (EI > 0) for A. sarta will slightly decrease to 40.14% (under A1B and A2 CCSs), while, for P. alba, the number areas capable of supplying suitable habitats will also marginally decrease to 50.39% (under A1B scenario), and this figure is estimated to drop to 48.41% (under A2 scenario) by the end century (2100). Asia, Europe, North America, South America, and Oceania have a high percentage of highly suitable areas for A. sarta development and P. alba growth under current climatic conditions; however, according to estimates of future climatic conditions, by the end century, only Asia, Europe, North America, and Oceania will have a high percentage of highly suitable areas for A. sarta development and P. alba growth. The range of highly suitable habitats is likely to increase in the northern hemisphere; however, this range is expected to shrink with regards to the southern hemisphere. The range contraction was higher under the A2 climate change scenario due to a higher warming trend than in the A1B scenario. Due to climate change, the range of A. sarta development shifted, as did the P. alba growth range, which, thanks to the suitable environmental conditions for the growth of P. alba, makes all those regions vulnerable to the introduction and development of A. sarta. Strict monitoring, prevention, and control measures at borders, airports, and seaports before the trade of P. alba and other suitable host species wood (logs/billets) are highly recommended to prevent the spread of A. sarta and ensure biodiversity security. It is expected that the A. sarta and P. alba climate models presented here will be useful for management purposes since both can be adapted to guide decisions about imparting resources to regions where the threat of pest invasion remains and away from regions where climate suitability is predicted to decrease in the future. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Diverse geographic, environmental, and ecological factors affect gene flow and adaptive genomic variation within species. With recent advances in landscape ecological modelling and high‐throughput DNA sequencing, it is now possible to effectively quantify and partition their relative contributions. Here, we use landscape genomics to identify determinants of genomic differentiation in the forest tent caterpillar, Malacosoma disstria, a widespread and irruptive pest of numerous deciduous tree species in North America. We collected larvae from multiple populations across Eastern Canada, where the species experiences a diversity of environmental gradients and feeds on a number of different host tree species, including trembling aspen (Populus tremuloides), sugar maple (Acer saccharum), red oak (Quercus rubra), and white birch (Betula papyrifera). Using a combination of reciprocal causal modelling (RCM) and distance‐based redundancy analyses (dbRDA), we show that differentiation of thousands of genome‐wide single nucleotide polymorphisms (SNPs) among individuals is best explained by a combination of isolation by distance, isolation by environment (spatial variation in summer temperatures and length of the growing season), and differences in host association. Configuration of suitable habitat inferred from ecological niche models was not significantly related to genomic differentiation, suggesting that M. disstria dispersal is agnostic with respect to habitat quality. Although population structure was not discretely related to host association, our modelling framework provides the first molecular evidence of host‐associated differentiation in M. disstria, congruent with previous documentation of reduced growth and survival of larvae moved between natal host species. We conclude that ecologically mediated selection is contributing to variation within M. disstria, and that divergent adaptation related to both environmental conditions and host association should be considered in ongoing research and management of this important forest pest.

Parasitic nematodes and hymenopteran parasitoids have been introduced and used extensively to control invasive Eurasian Sirex noctilio woodwasps in pine plantations in the Southern Hemisphere where no members of this community are native. Sirex noctilio has more recently invaded North America where Sirexassociated communities are native. Sirex noctilio and its parasitic nematode, Deladenus siricidicola, plus six native hymenopteran woodwasp parasitoids in New York and Pennsylvania, were sampled from 204 pines in 2011–2019. Sirex noctilio had become the most common woodwasp in this region and the native parasitoids associated with the native woodwasps had expanded their host ranges to use this invader. We investigated the distributions of these species among occupied trees and the interactions between S. noctilio and natural enemies as well as among the natural enemies. Sirex noctilio were strongly aggregated, with a few of the occupied trees hosting hundreds of woodwasps. Nematode parasitism was positively associated with S. noctilio density, and negatively associated with the density of rhyssine parasitoids. Parasitism by the parasitoid Ibalia leucospoides was positively associated with host (S. noctilio) density, while parasitism by the rhyssine parasitoids was negatively associated with density of S. noctilio. Thus, most S. noctilio come from a few attacked trees in a forest, and S. noctilio from those high-density trees experienced high parasitism by both the invasive nematode and the most abundant native parasitoid, I. l. ensiger. There is little evidence for direct competition between the nematodes and parasitoids. The negative association occurring between rhyssine parasitoids and I. l. ensiger suggests rhyssines may suffer from competition with I. l. ensiger which parasitize the host at an earlier life stage. In addition to direct competition with the native woodwasp Sirex nigricornis for suitable larval habitat within weakened trees, the large S. noctilio population increases the parasitoid and nematode populations, which may increase parasitism of S. nigricornis. [ABSTRACT FROM AUTHOR]

The western conifer seed bug (WCSB), Leptoglossus occidentalis, has expanded rapidly in the southern peninsula of Korea since it was first reported in southeastern Korea in 2010. Two types of human-mediated passive movements were devised for modeling the rapid advancement of the pest population in this study: traffic effects and forest-product transportation. A lattice structure model (LSM) was developed to accommodate the traffic effects pertaining to the local area along with the natural population dynamics of the pest. Separately, a spatial network model (SNM) was constructed to present the passive movement of the WCSB because of forest-product transportation between all local areas in Korea. The gravity rule was applied to obtain the parameters for forest-product transportation between the local areas. LSM and SNM were linked to the two present types of passive movements in the model. The model simulated fast, linear advancement in a short period, compared with slow, circular advancement because of the conventional natural diffusion process of populations. Simulation results were comparable to field data observed in the southern peninsula of Korea, matching the rapid advancement of about 400 km to the north area (Seoul) from the south area (Changwon) within six years and expanding across the nation in 10 years. Possible saturation of populations was predicted in the 2020s if survival conditions for the WCSB were favorable and no control efforts were given in field conditions. Dispersal because of SNM notably surpassed the dispersal simulated by LSM when the WCSB population rapidly dispersed over a wide area. The Allee-effect and contribution ratio of SNM were the factors governing the rapid expansion of pest populations. The possibility of using the combined model was further discussed to address different types of human-mediated passive movements associated with population dynamics in forest pest dispersal. [ABSTRACT FROM AUTHOR]

Ips typographus (L.) and Pityogenes chalcographus (L.) (Coleoptera: Curculionidae) are two common bark beetle species on Norway spruce in Eurasia. Multiple biotic and abiotic factors affect the life cycles of these two beetles, shaping their ecology and evolution. In this article, we provide a comprehensive and comparative summary of selected life-history traits. We highlight similarities and differences in biotic factors, like host range, interspecific competition, host colonization, reproductive behaviour and fungal symbioses. Moreover, we focus on the species' responses to abiotic factors and compare their temperature-dependent development and flight behaviour, cold adaptations and diapause strategies. Differences in biotic and abiotic traits might be the result of recent, species-specific evolutionary histories, particularly during the Pleistocene, with differences in glacial survival and postglacial recolonization. Finally, we discuss future research directions to understand ecological and evolutionary pathways of the two bark beetle species, for both basic research and applied forest management. [ABSTRACT FROM AUTHOR]

Aeolesthes sarta (Solsky 1871) (Coleoptera: Cerambycidae) is a polyphagous longhorned beetle species that primarily damages broadleaved tree species. This pest is distributed in the western and northern regions of Pakistan, where it caused serious damage to Populus spp. plantations. However, the growth and dispersal patterns of insects and pests are changing due to climate change. Modeling the range expansion or contraction of A. sarta development regions in Pakistan was the goal of the current study, assuming climate change might influence the geographical distribution of A. sarta in Pakistan. Under historical and future climatic conditions, A. sarta distribution areas were estimated using the CLIMEX model. Three time periods, 2030 (early century), 2070 (late century), and 2100 (end century), were forecasted for habitat suitability using the two climate change scenarios (CCSs) A1B and A2. Under the historic climatic condition (HCC), A. sarta was distributed in most areas of Pakistan, and its optimum habitat accounted for 71.67% of its total potential distribution. In the early-century period, optimum habitat dropped to 50.60% and 52.22% under A1B and A2 scenarios in the suitable condition. In the late-century period, optimum habitat further reduced to 31.76% and 30.60% under A1B and A2 scenarios. Moreover, at the end-century period, severe range shrinkage was predicted in the optimum habitat (19.99% under both CSSs). The model predicted a shift in the suitable habitat areas for A. sarta to the west and north. Furthermore, most climatically suitable areas under historic conditions became unsuitable during the end-century period. These projected results will assist in identifying the impacts of global warming on the possible distribution of A. sarta, thereby offering vital information for developing early forecasting and pest-prevention techniques to prevent further loss of forest and woodland trees. [ABSTRACT FROM AUTHOR]

Abstract Areas planted with Eucalyptus urophylla S.T. Blake variety platyphylla F. Muell. (Myrtaceae) expand annually in most regions of Brazil. Many lepidopteran species defoliate this plant, but with damage varying per species. The objective of this study was to identify the pest status of lepidopteran defoliators based in the faunistic analysis of these insects and of their natural enemies on E. urophylla variety platyphylla plantations in a representative producing region of Brazil. Adult moths of lepidopterans and of their natural enemies were captured using a light trap, installed every two weeks, from September 2016 to August 2018. A total of 183, 10, three and 139 lepidopteran species was captured and classified as primary, secondary, without defined importance to eucalypt plants and non-identified with 1,419, seven, 465 and 876 individuals, respectively. Two primary pest species were constants, two accessories and six accidentals and all secondary ones were accidentals. Six primary pest species were common and dominant and four non-dominants. Faunistic indices indicated the main lepidopteran species that should be monitored in pest management programs. Seven hymenopteran species (65 individuals), three dipterans (49 individuals) and two hemipterans (four individuals) were the natural enemies collected using light traps. The monitoring of lepidopteran pests with light traps can contribute to the management and to reduce damage and control costs for these species, besides identifying natural enemies for biological control programs in Eucalyptus plantations.

The frequent occurrence of forest diseases and insect pests has a significant impact on the forest ecosystem. The government needs to take measures to protect the forest ecosystem. The common management modes for forest pests and diseases include pesticide control, physical control, and biological control. In the process of governance, governments need to consider not only cost-effectiveness but also the impact on the ecosystem. In this article, the differential game model under these three modes is constructed, and the equilibrium results are compared and analyzed. Finally, the research conclusion is drawn that under the biological control mode, the income generated by the unit control quantity is inversely proportional to the balanced control quantity. However, under pesticide control and physical control modes, the revenue generated by the unit control quantity is proportional to the balanced control quantity. At the same time, under the biological control mode, the unit governance cost is proportional to the balanced control quantity. Under the pesticide control and physical control modes, the unit control cost is inversely proportional to the balanced control quantity. Social forces tend to adopt pesticide control. The government prefers physical control.

IntroductionScale insects (Hemiptera: Coccomorpha) feed on a wide variety of agricultural crops and forest and ornamental trees worldwide. These pest insects damage plants not only by causing sap loss but also by reducing the plant's photosynthetic activity. This is because the honeydew they produce acts as a substrate for mold, which covers leaf surfaces. In the last decades, several outbreaks of Physokermes spp. (soft-scale insects) have occurred throughout Europe and have partly been attributed to unusual weather conditions or climate change, as some species seem to be expanding their distribution range. However, the small size of these insects and their large intraspecific morphological variation have hindered the identification of the species responsible for outbreaks.MethodsIn this study, mitochondrial DNA (cytochrome c oxidase subunit I, COI), ribosomal RNA (28S), and nuclear (elongation factor 1α, EF1α) DNA markers were used to reconstruct the phylogenetic relationships of four Physokermes species sampled throughout Europe in 2013–2015.Results and discussionThe results allowed us to clearly distinguish P. hellenicus and P. inopinatus from each other, as these appeared in well-supported clades in the phylogenetic trees and from P. piceae and P. hemicryphys. However, P. hemicryphus appeared in a single clade in trees based on 28S and EF1α but among P. piceae in the COI tree. Further investigations are therefore required to determine the taxonomic status of P. piceae and P. hemicryphys, which seem to comprise a species complex.

Hybridization plays an important and underappreciated role in shaping the evolutionary trajectories of species. Following the introduction of a non‐native organism to a novel habitat, hybridization with a native congener may affect the probability of establishment of the introduced species. In most documented cases of hybridization between a native and a non‐native species, a mosaic hybrid zone is formed, with hybridization occurring heterogeneously across the landscape. In contrast, most naturally occurring hybrid zones are clinal in structure. Here, we report on a long‐term microsatellite data set that monitored hybridization between the invasive winter moth, Operophtera brumata (Lepidoptera: Geometridae), and the native Bruce spanworm, O. bruceata, over a 12‐year period. Our results document one of the first examples of the real‐time formation and geographic settling of a clinal hybrid zone. In addition, by comparing one transect in Massachusetts where extreme winter cold temperatures have been hypothesized to restrict the distribution of winter moth, and one in coastal Connecticut, where winter temperatures are moderated by Long Island Sound, we found that the location of the hybrid zone appeared to be independent of environmental variables and maintained under a tension model wherein the stability of the hybrid zone was constrained by population density, reduced hybrid fitness, and low dispersal rates. Documenting the formation of a contemporary clinal hybrid zone may provide important insights into the factors that shaped other well‐established hybrid zones. [ABSTRACT FROM AUTHOR]

Diverse geographic, environmental, and ecological factors affect gene flow and adaptive genomic variation within species. With recent advances in landscape ecological modelling and high‐throughput DNA sequencing, it is now possible to effectively quantify and partition their relative contributions. Here, we use landscape genomics to identify determinants of genomic differentiation in the forest tent caterpillar, Malacosoma disstria, a widespread and irruptive pest of numerous deciduous tree species in North America. We collected larvae from multiple populations across Eastern Canada, where the species experiences a diversity of environmental gradients and feeds on a number of different host tree species, including trembling aspen (Populus tremuloides), sugar maple (Acer saccharum), red oak (Quercus rubra), and white birch (Betula papyrifera). Using a combination of reciprocal causal modelling (RCM) and distance‐based redundancy analyses (dbRDA), we show that differentiation of thousands of genome‐wide single nucleotide polymorphisms (SNPs) among individuals is best explained by a combination of isolation by distance, isolation by environment (spatial variation in summer temperatures and length of the growing season), and differences in host association. Configuration of suitable habitat inferred from ecological niche models was not significantly related to genomic differentiation, suggesting that M. disstria dispersal is agnostic with respect to habitat quality. Although population structure was not discretely related to host association, our modelling framework provides the first molecular evidence of host‐associated differentiation in M. disstria, congruent with previous documentation of reduced growth and survival of larvae moved between natal host species. We conclude that ecologically mediated selection is contributing to variation within M. disstria, and that divergent adaptation related to both environmental conditions and host association should be considered in ongoing research and management of this important forest pest. [ABSTRACT FROM AUTHOR]

The walking-stick insect Ramulus mikado is occasionally considered a forest pest, as its mass occurrence can cause severe defoliation. It overwinters as eggs on the ground surface, and the hatched nymphs climb up to the host trees in spring. In this study, temperature-dependent development experiments were performed on R. mikado eggs under three constant temperatures (23.3, 28.3, and 29.2 °C) to extend the previously reported thermal response. The development times of eggs collected in summer and winter were also compared to investigate how development status is influenced by the seasons. The lower and upper developmental thresholds and thermal constants of R. mikado eggs were estimated to be 6.1 °C, 29.2 °C, and 1707.8 DD, respectively. The starting point for effective temperature effects on the eggs was estimated to be 1 August, based on the results of the experiment on field-collected eggs. A phenology model was constructed by using a development completion model scaled by the thermal constant, with a starting point of degree-day accumulation. The model showed good agreement, with a deviation of 3.2 ± 2.95 days between prediction and observation. The developed phenology model is useful for determining the appropriate timing for management decision-making regarding this insect.

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Accurate species delimitation is an important component of pest management. The Euwallacea fornicatus species complex (Coleoptera: Curculionidae: Scolytinae) includes a series of morphologically similar forest pests that cause huge economic losses both in invaded regions and in the native region. The current hypothesis about the species complex postulates the existence of four species: E. fornicatus (Eichhoff), E. fornicatior (Eggers), E. kuroshio Gomez and Hulcr, and E. perbrevis (Schedl). To test the current hypothesis and reveal the diversity in China, we explored the genetic diversity of the Euwallacea fornicatus complex using molecular approaches. Species and clades were delimited (using ABGD, bGMYC, mPTP and BP&P approaches) based on mitochondrial COI and 16S, and nuclear 18S-ITS1-5.8S, 28S and CAD. All specimens from continental China were E. fornicatus, consistently separating into three molecular taxonomic. Of the other species, E. perbrevis was recovered from Hainan. The distribution pattern and genetic diversity of these species contributes to the development of adequate control strategies since different species can cause different damage. [ABSTRACT FROM AUTHOR]

Eucalyptus spp. (Myrtaceae) is economically important worldwide and is native from Australia. Glycaspis brimblecombei (Hemiptera: Aphalaridae) is an insect that causes damages in eucalyptus plantations. Field observations show that highly infested plants (susceptible), less infested plants (less susceptible), and non-infested plants (resistant) can coexist at the same eucalyptus cultivation area. The aim of this study was to compare the preferences of Glycaspis brimblecombei with Eucalyptus spp. essential oil composition, evaluating the thermal behavior and searching for repellent compounds using chromatography. Simultaneous thermogravimetric and differential thermal analysis (TGA–DTA) results suggest that the less volatile essential oils were obtained from more resistant eucalyptus, with total mass loss temperature between 168 and 176 ºC. This behavior is due to the ratio between monoterpenes and sesquiterpenes in essential oils. Furthermore, D-limonene, caryophyllene, geranyl acetate, and other compounds may be correlated to the resistance against the insect. Gas chromatography–mass spectrometry (GC/MS) showed that susceptible samples had the highest concentrations of eucalyptol (77.0% and 49.8%) and lower concentration (3 and 9%) and variability of sesquiterpenes (7 and 10 compounds); additionally, they did not present β-guaiene, calamenene, α-copaene, α-terpinyl acetate, 1,4-cadinadiene, D-limonene, and caryophyllene in their essential oil composition. The eucalyptus resistance against Glycaspis brimblecombei is related to concentration and variability of sesquiterpenes, as well as the presence of specific compounds. [ABSTRACT FROM AUTHOR]

Emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) is a quarantine pest posing a threat to ash trees all over Europe. This wood-boring beetle native to Asia is quickly spreading in North America and European Russia, and approaching the European Union and the Middle East. It is important to study microorganisms associated with this pest, because the knowledge of its "natural enemies" and "natural allies" could be potentially used for the control of the pest. All previously published information about the A. planipennis microbiome was obtained in North America and China. We present the first study on procaryotes associated with A. planipennis in Europe. Alive larvae were sampled from under the bark of Fraxinus pennsylvanica in the Moscow Oblast and the gut microbiome was studied using metagenomic methods. Next-generation Illumina-based amplicon sequencing of the v3-v4 region 16S-RNA gene was performed. In total, 439 operational taxonomic units from 39 families and five phyla were detected. The dominant families in our samples were Pseudomonadaceae, Erwiniaceae and Enterobacteriaceae, in accordance with the published information on the larval gut microbiome in North America and China. We detected intracellular bacteria in A. planipennis for the first time, namely Rickettsia (Rickettsiaceae) and Rickettsiella (Diplorickettsiaceae). Representatives of the genus Rickettsia are known to be in mutualistic symbiosis with some phytophagous insects, while Rickettsiella bacteria are pathogenic to many arthropods. The finding of Rickettsia and Rickettsiella opens perspectives for future research on the interactions between these bacteria and A. planipennis and the possible use of these interactions for the control of the pest. [ABSTRACT FROM AUTHOR]

Balsam woolly adelgid (Adelges piceae; BWA) is an invasive forest pest in the US whose infestation in fir forests can cause widespread tree mortality. A growing body of evidence suggests that the severity of BWA's effects is linked to climatic conditions, where sites featuring seasonally warmer temperatures tend to demonstrate higher degrees of insect-induced forest degradation. Thus, a warming climate may promote the expansion of BWA-driven damage, particularly in highly susceptible subalpine fir (Abies lasiocarpa) forests. The degree to which climate change may foster BWA infestation and the relationship between current and future infestation damage severity are largely unknown. To understand BWA's potential climate-driven impacts on subalpine fir forests now and in the future, we built a field-validated, spatially explicit predictive model that estimates BWA infestation severity as a function of locally downscaled temperature variables. Using only four seasonal temperature variables, our model was able to explain over 78% of variance in measured severity. We applied that model to the prediction of severity for five different time periods (2020, 2040, 2060, 2080, and 2100), with the 2040 and onward predictions being driven by four separate climatic shared socioeconomic pathways (SSP126, SSP245, SSP370, and SSP585). These high resolution (∼30 m) maps were compared to spatially coincident modeled estimates of subalpine fir aboveground biomass, the results of which provide valuable insight into the degree to which BWA may drive forest degradation, loss of ecosystem services, and increase in available fuels. In northern Utah, the southeasternmost extent of BWA infestation in the western US, the two major mountain ranges, Wasatch and Uinta, demonstrated very different climatic susceptibility to infestation damage, with the former being highly exposed to BWA-induced degradation under even moderate climate projections, and the latter being fairly robust against BWA's effects in all but the most extreme climate scenarios. In 2020, 41% of the study area's subalpine fir biomass is climatically exposed to some level of damage from BWA. By 2100, even under moderate climate projections (SSP245), 79% will be exposed, with 37% predicted to feature relatively high severity. By placing our results within the context of the Resist, Accept, Direct land management framework, we offer spatially explicit guidance to inform current and future silvicultural practices to mitigate future damage to subalpine fir forests at the leading edge of BWA expansion in the western US. • BWA's damaging effects are highly predictable with high resolution temperature data. • We map 2020 – 2100 climatic exposure to BWA damage under four climate scenarios. • Comparing damage maps to biomass quantifies ecosystem effects and aids management. • In 2020, 41% of study area exposed to BWA effects, mainly in Wasatch Mountains. • By 2100, even under moderate climate projections, 79% of study area exposed to BWA. [ABSTRACT FROM AUTHOR]

The western conifer seed bug (WCSB), Leptoglossus occidentalis, has expanded rapidly in the southern peninsula of Korea since it was first reported in southeastern Korea in 2010. Two types of human-mediated passive movements were devised for modeling the rapid advancement of the pest population in this study: traffic effects and forest-product transportation. A lattice structure model (LSM) was developed to accommodate the traffic effects pertaining to the local area along with the natural population dynamics of the pest. Separately, a spatial network model (SNM) was constructed to present the passive movement of the WCSB because of forest-product transportation between all local areas in Korea. The gravity rule was applied to obtain the parameters for forest-product transportation between the local areas. LSM and SNM were linked to the two present types of passive movements in the model. The model simulated fast, linear advancement in a short period, compared with slow, circular advancement because of the conventional natural diffusion process of populations. Simulation results were comparable to field data observed in the southern peninsula of Korea, matching the rapid advancement of about 400 km to the north area (Seoul) from the south area (Changwon) within six years and expanding across the nation in 10 years. Possible saturation of populations was predicted in the 2020s if survival conditions for the WCSB were favorable and no control efforts were given in field conditions. Dispersal because of SNM notably surpassed the dispersal simulated by LSM when the WCSB population rapidly dispersed over a wide area. The Allee-effect and contribution ratio of SNM were the factors governing the rapid expansion of pest populations. The possibility of using the combined model was further discussed to address different types of human-mediated passive movements associated with population dynamics in forest pest dispersal.

The highly diverse insect family of true weevils, Curculionidae, includes many agricultural and forest pests. Pissodes strobi, commonly known as the spruce weevil or white pine weevil, is a major pest of spruce and pine forests in North America. Pissodes strobi larvae feed on the apical shoots of young trees, causing stunted growth and can destroy regenerating spruce or pine forests. Here, we describe the nuclear and mitochondrial Pissodes strobi genomes and their annotations, as well as the genome of an apparent Wolbachia endosymbiont. We report a substantial expansion of the weevil nuclear genome, relative to other Curculionidae species, possibly driven by an abundance of class II DNA transposons. The endosymbiont observed belongs to a group (supergroup A) of Wolbachia species that generally form parasitic relationships with their arthropod host. [ABSTRACT FROM AUTHOR]

Ips duplicatus (Coleoptera: Curculionidae) is a bark beetle that recently invaded southern Europe. It produces intense outbreaks in the spruce stands installed outside their natural area. Pheromone dispensers with different designs are used for monitoring this species. Compounds are released either by wick (ID Ecolure) or polyethene foil (ID RO and Pheagr IDU). We performed a series of laboratory and field experiments to compare the efficiency and sustainability of these dispensers in terms of pheromone release. The first experiment compared the Ips duplicatus capture dynamics between the ID Ecolure and ID RO in pheromones traps in three localities for 60 days. Release rates of used dispensers were evaluated in the same period. The second experiment analyzed headspace chemical composition in three dispensers (ID Ecolure, ID RO, Pheagr IDU) and tested their activity in pheromone traps. Active compounds content released by tested dispensers varied. The wick dispensers' release rates (ID Ecolure) were strongly reduced from 365 to 50 mg/day within two weeks and then steadily to 16 mg/day after 60 days. Release rates of the polyethene dispensers (ID RO) remained constant over 60 days (20–24 mg/day). The highest initial emission was in the ID Ecolure. The ratio of pheromone components (ipsdienol/E-myrcenol) was lower for ID Ecolure (5) and ID RO (10) and higher for Pheagr IDU (565). In the field experiments, significantly more Ips duplicatus were caught with ID Ecolure than ID RO and Pheagr IDU in the first two weeks. Later, the attractivity of ID RO remained high, but captures by ID Ecolure were significantly reduced. The captures of Ips typograhus were also considered. We propose that the wick-type dispensers are a promising tool for controlling the hibernating beetle generation. The foil release dispensers can be used to monitor Ips duplicatus flight activity. [ABSTRACT FROM AUTHOR]

The bark beetle Ips typographus is the most destructive insect pest in Norway spruce-dominated forests. Its potential to establish multiple generations per year (multivoltinism) is one major trait that makes this beetle a severe pest. Ips typographus enters diapause to adjust its life cycle to seasonally changing environments. Diapause is characterized by developmental and reproductive arrest; it prolongs generation time and thus affects voltinism. In I. typographus a facultative, photoperiod-regulated diapause in the adult stage has been described. In addition, the presence of an obligate, photoperiod-independent, diapause has been hypothesized. The diapause phenotype has important implications for I. typographus voltinism, as populations with obligate diapausing individuals would be univoltine. To test for the presence of different I. typographus diapause phenotypes, we exposed Central and Northern European individuals to a set of photoperiodic treatments. We used two ovarian traits (egg number and vitellarium size) that are associated with gonad development, to infer reproductive arrest and thus diapause. We found a distinct effect of photoperiod on ovarian development, with variable responses in Central and Northern European beetles. We observed obligate diapausing (independent of photoperiod) individuals in Northern Europe, and both facultative (photoperiod-regulated) as well as obligate diapausing individuals in Central Europe. Our results show within-species variation for diapause induction, an adaptation to match life cycles with seasonally fluctuating environmental conditions. As the diapause phenotype affects the potential number of generations per season, our data are the basis for assessing the risk of outbreaks of this destructive bark beetle. [ABSTRACT FROM AUTHOR]

The Sirex woodwasp Sirex noctilio Fabricius (Hymenoptera: Siricidae), a widespread invasive pest of pines in the Southern Hemisphere, was first detected in North America in 2004. This study assessed the impacts of life history traits, host resistance and species interactions on the demography of S. noctilio in New York, Pennsylvania and Vermont, then compared key metrics to those found in the native range in Galicia, Spain. Many trees naturally attacked by S. noctilio in North America produced no adult woodwasps, with 5 of 38 infested trees (13%) sampled across six sites yielding 64% of emerging insects. Reproductive success was highest in the introduced host scots pine, Pinus sylvestris, but native red pine, Pinus resinosa, produced larger insects. Sirex noctilio required one or sometimes two years to develop and sex ratios were male biased, 1:2.98 ♀:♂. Body size and fecundity were highly variable, but generally lower than observed in non-native populations in the Southern Hemisphere. Hymenopteran parasitoids killed approximately 20% of S. noctilio larvae and 63% of emerging adults were colonized by the parasitic nematode Deladenus siricidicola, although no nematodes entered eggs. Demographic models suggested that S. noctilio in the northeastern USA have a higher potential for population growth than populations in the native range: estimated finite factor of increase, λ, was 4.17-4.52 (depending on tree species colonized), compared to λ = 1.57 in Spain. [ABSTRACT FROM AUTHOR]

The defoliating caterpillar Sarsina violascens causes economic losses in Brazilian Eucalyptus crops. Information on the susceptibility of Eucalyptus species and hybrids to insect pests is scarce. As such, this study aimed to assess the development of S. violascens on Eucalyptus species and hybrids under laboratory conditions. Neonate caterpillars were reared on leaves of Eucalyptus grandis, E. urophylla, E. camaldulensis and E. globulus; and hybrids of E. urophylla x E.urophylla, E. urophylla × E. grandis, E. grandis × E. camaldulensis and E. urophylla × E. camaldulensis. Biological parameters such as instar and larval phase duration, pupal weight, adult longevity and fecundity, and eclosion rate were evaluated. Eucalyptus globulus is not an S. violascens host, leading to 100% larval mortality in the first instar. Eucalyptus grandis extended the larval phase of the insect and decreased larval survivorship and female pupal weight, resulting in high levels of deformity in adults and low egg eclosion, in addition to exhibiting significant antibiosis to S. violascens. Eucalyptus camaldulensis and VM-1 extended the larval period and reduced pupal weight. Eucalyptus urophylla was better suited to the development and reproduction of S. violascens than other Eucalyptus species and hybrids. E. grandis is a promising source of resistance to S. violascens. The use of resistant species and hybrids contributes to pest management, reducing the need for chemical control. [ABSTRACT FROM AUTHOR]

Mastigimas anjosi is an important pest of Cedrela fissilis in the southeastern and southern regions of Brazil. The objective of the present study was to investigate the effect of the temperature, relative humidity, rainfall and natural enemies on the flight activity of adults and the movement of M. anjosi nymphs, with two sampling methods, yellow sticky traps and direct collections on the leaves of C. fissilis trees. The sex ratio of this pest was also assessed. The number of M. anjosi individuals was negatively correlated with the minimum and maximum temperatures, with a population peak in late May and early June 2017. The numbers of individuals of this psyllid was positively correlated with the relative humidity and rainfall. Larvae and adults of Cycloneda sanguinea, Hippodamia convergens adults and Atopozelus opsimus nymphs and adults preyed upon M. anjosi adults and nymphs on C. fissilis leaves in the field. Mastigimas anjosi sex ratio was 0.46. Information about sampling methods of M. anjosi and its natural enemies is presented and can contribute to the integrated management of this pest in the field.

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A small number of longhorn beetle species (Coleoptera: Chrysomeloidea: Cerambycidae) have the potential to become invasive forest pests. International trade in live plants and wood packaging material are known invasion pathways for longhorn beetles. Once an invasive pest is intercepted in a new region, a rapid pest risk analysis is often needed to determine the appropriate response. For accurate risk quantification, natural history evidence is necessary. This information is also vital in preventing introduction. This study gathered insect collection data, especially references to host plants, of xylophagous longhorn beetles from the Institute of Zoology, Chinese Academy of Sciences, Beijing, China. Beetle associations with three important host groups were investigated: Fagaceae, Citrus spp., and avocado (Persea americana). We performed a systematic literature review to identify previously documented cerambycidae associated with these plants. Here, we report insect-plant host associations for 39 species of longhorn beetles based on a review of the literature; 43 interactions were documented, 10 interactions were novel. No host associations were recorded with avocado in China. This information serves as a foundation for pest risk analysis in determining threats posed by potentially invasive longhorn beetles into new regions. [ABSTRACT FROM AUTHOR]