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Copeland M, Landa S, Owoyemi AO, Jonika MM, Alfieri JM, Johnston JS, Sylvester TP, Kyre BR, Hoover Z, Hjelmen CE, Rieske LK, Blackmon H, Casola C. Genome assembly of the southern pine beetle ( Dendroctonus frontalis Zimmerman) reveals the origins of gene content reduction in Dendroctonus. ROYAL SOCIETY OPEN SCIENCE 2024; 11:240755. [PMID: 39665097 PMCID: PMC11631454 DOI: 10.1098/rsos.240755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 08/09/2024] [Accepted: 10/28/2024] [Indexed: 12/13/2024]
Abstract
Dendroctonus frontalis also known as southern pine beetle (SPB), is the most damaging insect forest pest in the southeastern United States. Genomic data are important to provide information on pest biology and to identify molecular targets to develop improved pest management approaches. Here, we produced a chromosome-level genome assembly of SPB using long-read sequencing data. Synteny analyses confirmed the conservation of the core Coleopteran Stevens elements and validated the bona fide SPB X chromosome. Transcriptomic data were used to obtain 39 588 transcripts corresponding to 13 354 putative protein-coding loci. Comparative analyses of gene content across 14 beetles and three other insects revealed several losses of conserved genes in the Dendroctonus clade and gene gains in SPB and Dendroctonus that were enriched for loci encoding membrane proteins and extracellular matrix proteins. While lineage-specific gene losses contributed to the gene content reduction observed in Dendroctonus, we also showed that widespread misannotation of transposable elements represents an important cause of the apparent gene expansion in several non-Dendroctonus species. Our findings uncovered distinctive features of the SPB gene complement and disentangled the role of biological and annotation-related factors contributing to gene content variation across beetles.
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Errbii M, Myrie A, Robinson D, Schultner E, Schrader L, Oettler J. Genetic Variation in Jamaican Populations of the Coffee Berry Borer, Hypothenemus hampei. Genome Biol Evol 2024; 16:evae217. [PMID: 39486017 PMCID: PMC11529894 DOI: 10.1093/gbe/evae217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2024] [Indexed: 11/03/2024] Open
Abstract
The coffee berry borer (CBB) Hypothenemus hampei was first described in Africa in 1867 and has spread to all major coffee-producing regions worldwide, including Jamaica. Using long-read sequencing, we produced a new high-quality reference genome (172.7 Mb) for the Jamaican strain of the CBB, with 93% of the genome assembled into 14 scaffolds. Whole genome sequencing of pooled samples from different populations across Jamaica showed that the CBB harbors low levels of genetic diversity alongside an excess of low-frequency alleles, indicative of a recent genetic bottleneck. The analyses also showed a recent surge in the activity of transposable elements (TEs), particularly LINE/R1 and LTR/Gypsy elements, within CBB populations. Our findings offer first insights into the evolutionary genomics of CBB populations in Jamaica, highlighting the potential role of TEs in shaping the genome of this important pest species.
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Bickerstaff JRM, Walsh T, Court L, Pandey G, Ireland K, Cousins D, Caron V, Wallenius T, Slipinski A, Rane R, Escalona HE. Chromosome Structural Rearrangements in Invasive Haplodiploid Ambrosia Beetles Revealed by the Genomes of Euwallacea fornicatus (Eichhoff) and Euwallacea similis (Ferrari) (Coleoptera, Curculionidae, Scolytinae). Genome Biol Evol 2024; 16:evae226. [PMID: 39431789 PMCID: PMC11542627 DOI: 10.1093/gbe/evae226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 09/30/2024] [Accepted: 10/07/2024] [Indexed: 10/22/2024] Open
Abstract
Bark and ambrosia beetles are among the most ecologically and economically damaging introduced plant pests worldwide. Life history traits including polyphagy, haplodiploidy, inbreeding polygyny, and symbiosis with fungi contribute to their dispersal and impact. Species vary in their interactions with host trees, with many attacking stressed or recently dead trees, such as the globally distributed Euwallacea similis (Ferrari). Other species, like the Polyphagous Shot Hole Borer Euwallacea fornicatus (Eichhoff), can attack over 680 host plants and is causing considerable economic damage in several countries. Despite their notoriety, publicly accessible genomic resources for Euwallacea Hopkins species are scarce, hampering our understanding of their invasive capabilities as well as modern control measures, surveillance, and management. Using a combination of long and short read sequencing platforms, we assembled and annotated high quality (BUSCO > 98% complete) pseudo-chromosome-level genomes for these species. Comparative macrosynteny analysis identified an increased number of pseudo-chromosome scaffolds in the haplodiploid inbreeding species of Euwallacea compared to diploid outbred species, due to fission events. This suggests that life history traits can impact chromosome structure. Further, the genome of E. fornicatus had a higher relative proportion of repetitive elements, up to 17% more, than E. similis. Metagenomic assembly pipelines identified microbiota associated with both species including Fusarium fungal symbionts and a novel Wolbachia strain. These novel genomes of haplodiploid inbreeding species will contribute to the understanding of how life history traits are related to their evolution and to the management of these invasive pests.
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Naseer A, Singh VV, Sellamuthu G, Synek J, Mogilicherla K, Kokoska L, Roy A. Insights into the Detoxification of Spruce Monoterpenes by the Eurasian Spruce Bark Beetle. Int J Mol Sci 2024; 25:10209. [PMID: 39337695 PMCID: PMC11432361 DOI: 10.3390/ijms251810209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2024] [Revised: 09/16/2024] [Accepted: 09/18/2024] [Indexed: 09/30/2024] Open
Abstract
Plant defence mechanisms, including physical barriers like toughened bark and chemical defences like allelochemicals, are essential for protecting them against pests. Trees allocate non-structural carbohydrates (NSCs) to produce secondary metabolites like monoterpenes, which increase during biotic stress to fend off pests like the Eurasian spruce bark beetle, ESBB (Ips typographus). Despite these defences, the ESBB infests Norway spruce, causing significant ecological damage by exploiting weakened trees and using pheromones for aggregation. However, the mechanism of sensing and resistance towards host allelochemicals in ESBB is poorly understood. We hypothesised that the exposure of ESBB to spruce allelochemicals, especially monoterpenes, leads to an upsurge in the important detoxification genes like P450s, GSTs, UGTs, and transporters, and at the same time, genes responsible for development must be compromised. The current study demonstrates that exposure to monoterpenes like R-limonene and sabiene effectively elevated detoxification enzyme activities. The differential gene expression (DGE) analysis revealed 294 differentially expressed (DE) detoxification genes in response to R-limonene and 426 DE detoxification genes in response to sabiene treatments, with 209 common genes between the treatments. Amongst these, genes from the cytochrome P450 family 4 and 6 genes (CP4 and CP6), esterases, glutathione S-transferases family 1 (GSTT1), UDP-glucuronosyltransferase 2B genes (UDB), and glucose synthesis-related dehydrogenases were highly upregulated. We further validated 19 genes using RT-qPCR. Additionally, we observed similar high expression levels of detoxification genes across different monoterpene treatments, including myrcene and α-pinene, suggesting a conserved detoxification mechanism in ESBB, which demands further investigation. These findings highlight the potential for molecular target-based beetle management strategies targeting these key detoxification genes.
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Johny J, Große-Wilde E, Kalinová B, Roy A. Antennal Transcriptome Screening and Identification of Chemosensory Proteins in the Double-Spine European Spruce Bark Beetle, Ips duplicatus (Coleoptera: Scolytinae). Int J Mol Sci 2024; 25:9513. [PMID: 39273461 PMCID: PMC11395090 DOI: 10.3390/ijms25179513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 08/29/2024] [Accepted: 08/30/2024] [Indexed: 09/15/2024] Open
Abstract
The northern bark beetle, Ips duplicatus, is an emerging economic pest, reportedly infesting various species of spruce (Picea spp.), pine (Pinus spp.), and larch (Larix spp.) in Central Europe. Recent climate changes and inconsistent forest management practices have led to the rapid spread of this species, leaving the current monitoring strategies inefficient. As understanding the molecular components of pheromone detection is key to developing novel control strategies, we generated antennal transcriptomes from males and females of this species and annotated the chemosensory proteins. We identified putative candidates for 69 odorant receptors (ORs), 50 ionotropic receptors (IRs), 25 gustatory receptors (GRs), 27 odorant-binding proteins (OBPs), including a tetramer-OBP, 9 chemosensory proteins (CSPs), and 6 sensory neuron membrane proteins (SNMPs). However, no sex-specific chemosensory genes were detected. The phylogenetic analysis revealed conserved orthology in bark beetle chemosensory proteins, especially with a major forest pest and co-habitant, Ips typographus. Recent large-scale functional studies in I. typographus chemoreceptors add greater significance to the orthologous sequences reported here. Nevertheless, identifying chemosensory genes in I. duplicatus is valuable to understanding the chemosensory system and its evolution in bark beetles (Coleoptera) and, generally, insects.
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Bragard C, Baptista P, Chatzivassiliou E, Di Serio F, Gonthier P, Jaques Miret JA, Justesen AF, Magnusson CS, Milonas P, Navas-Cortes JA, Parnell S, Potting R, Reignault PL, Stefani E, Thulke HH, Van der Werf W, Vicent Civera A, Yuen J, Zappalà L, Grégoire JC, Battisti A, Malumphy C, Faccoli M, Kertesz V, Marchioro M, Martinez I, Ortis G, Rassati D, Ruzzier E, MacLeod A. Pest categorisation of non-EU Scolytinae on non-coniferous hosts. EFSA J 2024; 22:e8889. [PMID: 39286543 PMCID: PMC11403304 DOI: 10.2903/j.efsa.2024.8889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/19/2024] Open
Abstract
The EFSA Panel on Plant Health performed a group pest categorisation for the EU territory of non-EU Scolytinae (Coleoptera: Curculionidae) on non-coniferous hosts, which total 6495 known species. Most species attack apparently healthy, weakened or dead trees, either feeding on the phloem ('bark beetles' subgroup) or on fungi inoculated into the sapwood ('ambrosia beetles' subgroup). Smaller subgroups feed and reproduce in seeds and fruits, or in herbaceous plants. Some species are polygynous, the males initiate a gallery or a chamber on or in a new host and attract females. Others are monogamous, and the females initiate the new galleries. Many species respond to primary volatile attractants emitted by the hosts, and some produce aggregation pheromones that attract conspecifics of both sexes. The species attacking living hosts are often associated with fungi that contribute to weakening the host defences and provide nutrients to the insects. Some are inbreeding; the males in the offspring mate with their sisters and rarely leave their natal tree. The larvae of all species develop and pupate within their hosts. Based on catalogues and other published data, a database was constructed providing information on hosts, feeding and reproductive habits, geographic distribution and the Köppen-Geiger climate types in countries where species occur. The Scolytinae were screened to exclude species in the following categories: (i) 708 species attacking conifers; (ii) 127 species present in at least four EU Member States and (iii) 440 species occurring in areas with climatic conditions not occurring in the EU. Among the remaining 5220 species, 88 species known for their mobility, occupying at least two landmasses separated by geographical barriers and some of which had impact levels documented in literature, were extracted. They were grouped into four subcategories: (i) 12 species with high impact on plant health; (ii) 16 species with low or doubtful impact; (iii) 48 species with no impact; (iv) 12 species with no impact and which had never been recorded as 'introduced' in the consulted catalogues but occurring on at least two landmasses. All 88 species could enter the EU with wood or wood products, or with plants for planting, and could establish because host plants are available, and climate is suitable in parts of the EU. Control measures to inhibit introduction are available. There is considerable uncertainty regarding the potential impact of many species. Methods for the reliable identification of many species are lacking. For some species of non-EU Scolytinae on non-coniferous hosts, all criteria assessed by EFSA for consideration as potential quarantine pest are met. Nevertheless, the Panel was not able to develop a method to discriminate confidently between species that clearly meet the criteria for potential quarantine pest status and those that do not.
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Zhou Y, Li T, He X, Wang X, Wang F, Li X. Efficient Biosynthesis of (+)-α-Pinene and de Novo Synthesis of (+)- cis-Verbenol in Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:18890-18897. [PMID: 39140858 DOI: 10.1021/acs.jafc.4c05387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Bark beetles, major pests that bore into forest stems, cause significant economic damage to forests globally. (+)-α-Pinene is the precursor to (+)-cis-verbenol, a crucial component of the aggregation pheromones produced by bark beetles. This paper describes the de novo synthesis of (+)-cis-verbenol in Escherichia coli. Initially, the truncation position of (+)-α-pinene synthase (PtPS30 from Pinus taeda) and monoterpene precursor (geranyl diphosphate/neryl diphosphate) synthases were evaluated. Neryl diphosphate synthase from Solanum lycopersicum (SlNPPS1) and truncated (+)-α-pinene synthase (PtPS30-39) were selected as promising candidates. Subsequently, the titer of (+)-α-pinene was significantly increased 8.9-fold by using the fusion tag CM29, which enhanced the solubility of PtPS30-39. In addition, by optimizing expression elements (ribosomal binding sites, linkers, and up elements) and overexpressing CM29*PtPS30-39, a yield of 134.12 mg/L (+)-α-pinene was achieved. Finally, the first de novo synthesis of enantiopure (+)-cis-verbenol was achieved by introducing a cytochrome P450 mutant from Pseudomonas putida (P450camF89W,Y98F,L246A), resulting in a yield of 11.13 mg/L. This study lays the groundwork for developing verbenol-based trapping technology for controlling bark beetles.
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Wang M, Gao C, Fu N, Ren L, Luo Y. Resource Sharing between the Invasive Sirex noctilio and Native Woodborers and Beetles in Pinus Plantations. INSECTS 2024; 15:478. [PMID: 39057211 PMCID: PMC11277501 DOI: 10.3390/insects15070478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 06/18/2024] [Accepted: 06/25/2024] [Indexed: 07/28/2024]
Abstract
Sirex noctilio, a European woodwasp, occasionally shares resources with the native S. nitobei and other colonizers in northeast China. The impact of its coexistence on individual species remains unclear. Random sampling was conducted to assess the patterns and extent of insect co-colonization across various spatial scales. Additionally, we analyzed wood sections to determine the density, adult size, and distribution of the two Sirex species. Spatial scales revealed negative associations (Asemum striatum and Phaenops sp.) and neutral ones (Ips acuminatus) between woodwasps and other co-colonizers. Clustering of woodwasps and Phaenops sp. occurred at a small scale (0-7.3 m). Regression analysis showed a positive correlation between the chance of woodwasp attacks and past attacks on the same host, with little impact from other colonization factors. The distribution and body size of S. noctilio within the tree appeared unaffected by S. nitobei's presence. In the presence of S. noctilio, S. nitobei tended to lay eggs in damaged sections. At the stand level, the overall impact of S. noctilio on S. nitobei population density is likely positive because S. nitobei prefer weaker trees, a preference potentially influenced by initial attacks from S. noctilio on healthier hosts.
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Jordal BH. An integrated taxonomic revision of Ctonoxylon (Coleoptera, Curculionidae, Scolytinae) reveals new Malagasy species originating from multiple recent colonisations of the island. Zookeys 2024; 1203:95-130. [PMID: 38846746 PMCID: PMC11150870 DOI: 10.3897/zookeys.1203.123757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 05/10/2024] [Indexed: 06/09/2024] Open
Abstract
Ctonoxylon is a strictly Afrotropical genus of bark beetles breeding under bark of rainforest trees and lianas. A taxonomic revision of the genus included a molecular phylogenetic analysis of ten species based on three gene fragments and was compared to a morphology-based tree topology for all 24 currently recognised species. Four species are described as new to science: Ctonoxylontorquatum, sp. nov., Ctonoxylontuberculatum, sp. nov., Ctonoxylonquadrispinum, sp. nov., all from Madagascar, and Ctonoxylonpilosum, sp. nov. from Cameroon. Ctonoxylonhirsutum Hagedorn, 1910, stat. rev. is resurrected from synonymy with C.flavescens Hagedorn, 1910, and C.atrum Browne, 1965 stat. rev. from its synonymy with C.methneri Eggers, 1922 (as C.hamatum Schedl, 1941). The following species have new synonymies suggested: Ctonoxylonfestivum Schedl, 1941 (= C.dentigerum Schedl, 1941, syn. nov.), C.methneri Eggers, 1922 (= C.hamatum Schedl, 1941, syn. nov., = C.griseum Schedl, 1941, syn. nov.), C.montanum Eggers, 1922 (= C.longipilum Eggers, 1935, syn. nov., = C.nodosum Eggers, 1940, syn. nov.), C.camerunum Hagedorn, 1910 (= C.conradti Schedl, 1939, syn. nov.), and C.spinifer Eggers, 1920 (= C.setifer Eggers, 1920, syn. nov.). New country records are noted for C.festivum (Tanzania), C.flavescens (Uganda), C.camerunum (Liberia), C.crenatum Hagedorn, 1910 (Democratic Republic of the Congo), C.spathifer Schedl, 1941 (Ghana), C.atrum (Cameroon), and C.spinifer (Madagascar), with patterns in distribution and colonisation of Madagascar discussed. An identification key with pictures of all species is provided.
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Copeland M, Landa S, Owoyemi A, Jonika MM, Alfieri J, Sylvester T, Hoover Z, Hjelmen CE, Spencer Johnston J, Kyre BR, Rieske LK, Blackmon H, Casola C. Genome assembly of the southern pine beetle ( Dendroctonus frontalis Zimmerman) reveals the origins of gene content reduction in Dendroctonus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.08.592785. [PMID: 38766115 PMCID: PMC11100688 DOI: 10.1101/2024.05.08.592785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Dendroctonus frontalis, also known as southern pine beetle (SPB), represents the most damaging forest pest in the southeastern United States. Strategies to predict, monitor and suppress SPB outbreaks have had limited success. Genomic data are critical to inform on pest biology and to identify molecular targets to develop improved management approaches. Here, we produced a chromosome-level genome assembly of SPB using long-read sequencing data. Synteny analyses confirmed the conservation of the core coleopteran Stevens elements and validated the bona fide SPB X chromosome. Transcriptomic data were used to obtain 39,588 transcripts corresponding to 13,354 putative protein-coding loci. Comparative analyses of gene content across 14 beetle and 3 other insects revealed several losses of conserved genes in the Dendroctonus clade and gene gains in SPB and Dendroctonus that were enriched for loci encoding membrane proteins and extracellular matrix proteins. While lineage-specific gene losses contributed to the gene content reduction observed in Dendroctonus, we also showed that widespread misannotation of transposable elements represents a major cause of the apparent gene expansion in several non-Dendroctonus species. Our findings uncovered distinctive features of the SPB gene complement and disentangled the role of biological and annotation-related factors contributing to gene content variation across beetles.
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Pineda-Mendoza RM, Gutiérrez-Ávila JL, Salazar KF, Rivera-Orduña FN, Davis TS, Zúñiga G. Comparative metabarcoding and biodiversity of gut-associated fungal assemblages of Dendroctonus species (Curculionidae: Scolytinae). Front Microbiol 2024; 15:1360488. [PMID: 38525076 PMCID: PMC10959539 DOI: 10.3389/fmicb.2024.1360488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Accepted: 02/15/2024] [Indexed: 03/26/2024] Open
Abstract
The genus Dendroctonus is a Holarctic taxon composed of 21 nominal species; some of these species are well known in the world as disturbance agents of forest ecosystems. Under the bark of the host tree, these insects are involved in complex and dynamic associations with phoretic ectosymbiotic and endosymbiotic communities. Unlike filamentous fungi and bacteria, the ecological role of yeasts in the bark beetle holobiont is poorly understood, though yeasts were the first group to be recorded as microbial symbionts of these beetles. Our aim was characterize and compare the gut fungal assemblages associated to 14 species of Dendroctonus using the internal transcribed spacer 2 (ITS2) region. A total of 615,542 sequences were recovered yielding 248 fungal amplicon sequence variants (ASVs). The fungal diversity was represented by 4 phyla, 16 classes, 34 orders, 54 families, and 71 genera with different relative abundances among Dendroctonus species. The α-diversity consisted of 32 genera of yeasts and 39 genera of filamentous fungi. An analysis of β-diversity indicated differences in the composition of the gut fungal assemblages among bark beetle species, with differences in species and phylogenetic diversity. A common core mycobiome was recognized at the genus level, integrated mainly by Candida present in all bark beetles, Nakazawaea, Cladosporium, Ogataea, and Yamadazyma. The bipartite networks confirmed that these fungal genera showed a strong association between beetle species and dominant fungi, which are key to maintaining the structure and stability of the fungal community. The functional variation in the trophic structure was identified among libraries and species, with pathotroph-saprotroph-symbiotroph represented at the highest frequency, followed by saprotroph-symbiotroph, and saprotroph only. The overall network suggested that yeast and fungal ASVs in the gut of these beetles showed positive and negative associations among them. This study outlines a mycobiome associated with Dendroctonus nutrition and provides a starting point for future in vitro and omics approaches addressing potential ecological functions and interactions among fungal assemblages and beetle hosts.
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Zaman R, Shah A, Shah A, Ullah A, Ishangulyyeva G, Erbilgin N. Unraveling the multifaceted effects of climatic factors on mountain pine beetle and its interaction with fungal symbionts. GLOBAL CHANGE BIOLOGY 2024; 30:e17207. [PMID: 38413744 DOI: 10.1111/gcb.17207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/24/2024] [Accepted: 02/10/2024] [Indexed: 02/29/2024]
Abstract
Mountain pine beetles (MPBs) pose a substantial threat to North American pine forests, causing extensive tree mortality over large areas. Their tree-killing ability is closely linked to mass aggregation on host trees triggered via pheromones and dependence on their symbiotic fungi. However, the influence of a changing climate on the biology of MPBs and their co-evolved interactions with their fungal symbionts remains uncertain. To investigate this, male and female pairs of beetles were introduced into freshly cut logs from lodgepole pine trees and placed in controlled climate chambers with manipulated environmental conditions, including two levels of CO2 (ambient vs. 1000 ppm), O3 (ambient vs. 100 ppb) and humidity (33% vs. 65%). The beetle-infested logs were left in these chambers for 1 month and then returned to ambient conditions until brood emergence. Emerging broods were collected for further analysis. Additionally, three species of fungal symbionts (Grosmannia clavigera, Ophiostoma montium and Leptographium longiclavatum) were subjected to the same CO2 , O3 and humidity conditions for 5 days. Lower humidity promoted MPB reproduction and fungal growth. Elevated CO2 accelerated larval growth and emergence while improving brood pheromone production. Elevated O3 had a negative impact on MPB reproduction and brood fitness while improving its immune responses to an entomopathogenic fungus (Beauveria bassiana). It also inhibited fungal growth and reproduction, whereas elevated CO2 had varied (positive or negative) effects on fungal growth and ergosterol (proxy to fungal mass) production depending on the fungal species. Together, these findings suggest that climate change can potentially alter the interactions between MPBs and their fungal symbionts, highlighting the importance of understanding how climate change affects forest pests and their symbiotic relationships to develop effective management strategies in the future.
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Baños-Quintana AP, Gershenzon J, Kaltenpoth M. The Eurasian spruce bark beetle Ips typographus shapes the microbial communities of its offspring and the gallery environment. Front Microbiol 2024; 15:1367127. [PMID: 38435688 PMCID: PMC10904642 DOI: 10.3389/fmicb.2024.1367127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 01/29/2024] [Indexed: 03/05/2024] Open
Abstract
The Eurasian spruce bark beetle (Ips typographus) is currently the most economically relevant pest of Norway spruce (Picea abies). Ips typographus associates with filamentous fungi that may help it overcome the tree's chemical defenses. However, the involvement of other microbial partners in this pest's ecological success is unclear. To understand the dynamics of the bark beetle-associated microbiota, we characterized the bacterial and fungal communities of wild-collected and lab-reared beetles throughout their development by culture-dependent approaches, meta-barcoding, and quantitative PCR. Gammaproteobacteria dominated the bacterial communities, while the fungal communities were mainly composed of yeasts of the Saccharomycetales order. A stable core of microbes is shared by all life stages, and is distinct from those associated with the surrounding bark, indicating that Ips typographus influences the microbial communities of its environment and offspring. These findings coupled with our observations of maternal behavior, suggest that Ips typographus transfers part of its microbiota to eggs via deposition of an egg plug treated with maternal secretions, and by inducing an increase in abundance of a subset of taxa from the adjacent bark.
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Spiecker H, Kahle HP. Climate-driven tree growth and mortality in the Black Forest, Germany-Long-term observations. GLOBAL CHANGE BIOLOGY 2023; 29:5908-5923. [PMID: 37551846 DOI: 10.1111/gcb.16897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 07/07/2023] [Indexed: 08/09/2023]
Abstract
Episodic tree mortality can be caused by various reasons. This study describes climate-driven tree mortality and tree growth in the Black Forest mountain range in Germany. It is based on a 68-year consistent data series describing the annual mortality of all trees growing in a forest area of almost 250 thousand ha. The study excludes mortality caused by storm, snow and ice, and fire. The sequence of the remaining mortality, the so-called "desiccated trees," is analyzed and compared with the sequence of the climatic water balance during the growing season and the annual radial growth of Norway spruce in the Black Forest. The annual radial growth series covers 121 years and the climatic water balance series 140 years. These unique time series enable a quantitative assessment of multidecadal drought and heat impacts on growth and mortality of forest trees on a regional spatial scale. Data compiled here suggest that the mortality of desiccated trees in the Black Forest during the last 68 years is driven by the climatic water balance. Decreasing climatic water balance coincided with an increase in tree mortality and growth decline. Consecutive hot and dry summers enhance mortality and growth decline as a consequence of drought legacies lasting several years. The sensitivity of tree growth and mortality to changes in the climatic water balance increases with the decreasing trend of the climatic water balance. The findings identify the climatic water balance as the main driver of mortality and growth variation during the 68-year observation period on a landscape-scale including a variety of different sites. They suggest that bark beetle population dynamics modify mortality rates. They as well provide evidence that the mortality during the last 140 years never was as high as in the most recent years.
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Belilov S, Todorov I, Georgieva M, Georgiev G. New parasitoid (Hymenoptera, Chalcidoidea) records of bark beetles (Coleoptera, Curculionidae, Scolytinae) in pine plantations in Bulgaria. Biodivers Data J 2023; 11:e109325. [PMID: 37809279 PMCID: PMC10559145 DOI: 10.3897/bdj.11.e109325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/19/2023] [Indexed: 10/10/2023] Open
Abstract
Background In 2020 and 2021, chalcidoid parasitoids (Hymenoptera, Chalcidoidea) of bark beetles in pine (Pinus spp.) plantations were studied in Bulgaria. Samples (cuttings of stems and branches) of pine trees infested by bark beetles were collected from seven plantations of Pinussylvestris and P.nigra in Bulgaria. From each sampling plot, five cuttings were collected and placed in photoeclectors in laboratory conditions (18-22ºC). Emerged bark beetles and parasitoids were regularly gathered and fixed in ethanol. New information Six parasitoid species - Dinotiscuscolon, Metacolusazureus, M.unifasciatus, Rhopalicusquadratus, R.tutela (Chalcidoidea: Pteromalidae) and Heydeniapretiosa (Chalcidoidea, Heydeniidae) were reared from five bark beetle hosts (Ipsacuminatus, Pityogenesbistridentatus, Pityophthoruspityographus, Tomicuspiniperda and T.minor). Amongst them, three species (H.pretiosa, M.azureus and R.quadratus) are recorded as new for Bulgarian fauna.
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Veselská T, Švec K, Kostovčík M, Peral-Aranega E, Garcia-Fraile P, Křížková B, Havlíček V, Saati-Santamaría Z, Kolařík M. Proportions of taxa belonging to the gut core microbiome change throughout the life cycle and season of the bark beetle Ips typographus. FEMS Microbiol Ecol 2023:fiad072. [PMID: 37370225 DOI: 10.1093/femsec/fiad072] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2023] Open
Abstract
The European spruce bark beetle, Ips typographus, is a serious pest of spruce forests in Europe, and its invasion and development inside spruce tissues are facilitated by microorganisms. We investigated the core gut bacterial and fungal microbiomes of I. typographus throughout its life cycle in spring and summer generations. We used cultivation techniques and molecular identification in combination with DNA and RNA metabarcoding. Our results revealed that communities differ in the throughout the life cycle and generations proportion of dominantly associated microbes, rather than changes in species composition. The bacteriome consisted mostly of the phylum Gammaproteobacteria, with the most common orders and genera being Enterobacteriales (Erwinia and Serratia), Pseudomonadales (Pseudomonas) and Xanthomonadales. The fungal microbiome was dominated by yeasts (Saccharomycetes-Wickerhamomyces, Kuraishia and Nakazawaea), followed by Sordariomycetes (Ophiostoma bicolor and Endoconidiophora polonica). We did not observe any structure ensuring long-term persistence of microbiota on any part of gut epithelium, suggesting that microbial cells are more likely to pass through the beetle's gut with chyme. The most abundant taxa in beetle's gut were also identified as dominant in intact spruce phloem. Therefore, we propose that these taxa are acquired from the environment rather than specifically vectored between generations.
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Patacca M, Lindner M, Lucas‐Borja ME, Cordonnier T, Fidej G, Gardiner B, Hauf Y, Jasinevičius G, Labonne S, Linkevičius E, Mahnken M, Milanovic S, Nabuurs G, Nagel TA, Nikinmaa L, Panyatov M, Bercak R, Seidl R, Ostrogović Sever MZ, Socha J, Thom D, Vuletic D, Zudin S, Schelhaas M. Significant increase in natural disturbance impacts on European forests since 1950. GLOBAL CHANGE BIOLOGY 2023; 29:1359-1376. [PMID: 36504289 PMCID: PMC10107665 DOI: 10.1111/gcb.16531] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 11/08/2022] [Accepted: 11/11/2022] [Indexed: 05/26/2023]
Abstract
Over the last decades, the natural disturbance is increasingly putting pressure on European forests. Shifts in disturbance regimes may compromise forest functioning and the continuous provisioning of ecosystem services to society, including their climate change mitigation potential. Although forests are central to many European policies, we lack the long-term empirical data needed for thoroughly understanding disturbance dynamics, modeling them, and developing adaptive management strategies. Here, we present a unique database of >170,000 records of ground-based natural disturbance observations in European forests from 1950 to 2019. Reported data confirm a significant increase in forest disturbance in 34 European countries, causing on an average of 43.8 million m3 of disturbed timber volume per year over the 70-year study period. This value is likely a conservative estimate due to under-reporting, especially of small-scale disturbances. We used machine learning techniques for assessing the magnitude of unreported disturbances, which are estimated to be between 8.6 and 18.3 million m3 /year. In the last 20 years, disturbances on average accounted for 16% of the mean annual harvest in Europe. Wind was the most important disturbance agent over the study period (46% of total damage), followed by fire (24%) and bark beetles (17%). Bark beetle disturbance doubled its share of the total damage in the last 20 years. Forest disturbances can profoundly impact ecosystem services (e.g., climate change mitigation), affect regional forest resource provisioning and consequently disrupt long-term management planning objectives and timber markets. We conclude that adaptation to changing disturbance regimes must be placed at the core of the European forest management and policy debate. Furthermore, a coherent and homogeneous monitoring system of natural disturbances is urgently needed in Europe, to better observe and respond to the ongoing changes in forest disturbance regimes.
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Ryss AY, Subbotin SA. New Records of Wood- and Bark-Inhabiting Nematodes from Woody Plants with a Description of Bursaphelenchus zvyagintsevi sp. n. (Aphelenchoididae: Parasitaphelenchinae) from Russia. PLANTS (BASEL, SWITZERLAND) 2023; 12:382. [PMID: 36679095 PMCID: PMC9860568 DOI: 10.3390/plants12020382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/11/2023] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Wood- and bark-inhabiting parasitic nematodes are of great economic importance. Nematodes can cause wilt diseases in conifers and deciduous trees. In 2014-2022, during nematology surveys conducted in different regions of Russia and Belarus, adults and dauer juveniles of nematodes were collected from wood, bark and beetle vectors. Using traditional morphological taxonomic characters integrated with molecular criteria, we identified in the studied samples the following nematode species: Aphelenchoides heidelbergi, Bursaphelenchus eremus, B. fraudulentus, B. michalskii, B. mucronatus, B. willibaldi, Deladenus posteroporus, Diplogasteroides nix and Laimaphelenchus hyrcanus, several unidentified species: Aphelenchoides sp.1 and sp.2, Cryptaphelenchus sp.1, sp.2 and sp.3, Laimaphelenchus sp.1, Micoletzkya sp.1, Parasitaphelenchus sp.1, Parasitorhabditis sp.1, three unidentified tylenchid nematodes and a new species, Bursaphelenchus zvyagintsevi sp.n. Morphological descriptions and molecular characterization are provided for B. zvyagintsevi sp. n. belonging to the Abietinus group and B. michalskii belonging to the Eggersi group. Findings of Aphelenchoides heidelbergi, Bursaphelenchus eremus, B. michalskii, Deladenus posteroporus, Diplogasteroides nix and Laimaphelenchus hyrcanus are new records for Russia. Phylogenetic positions of studied species were reconstructed using D2-D3 expansion segments of 28S rRNA gene sequence analysis. The data obtained in this study may help to detect the refugia of opportunistic plant pests and find possible native biocontrol nematode agents of insect vectors causing diseases.
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Rivera-Orduña FN, Pineda-Mendoza RM, Vega-Correa B, López MF, Cano-Ramírez C, Zhang XX, Chen WF, Zúñiga G. A polyphasic taxonomy analysis reveals the presence of an ecotype of Rahnella contaminans associated with the gut of Dendroctonus- bark beetles. Front Microbiol 2023; 14:1171164. [PMID: 37180241 PMCID: PMC10174453 DOI: 10.3389/fmicb.2023.1171164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 04/03/2023] [Indexed: 05/16/2023] Open
Abstract
Species belonging to the genus Rahnella are dominant members of the core gut bacteriome of Dendroctonus-bark beetles, a group of insects that includes the most destructive agents of pine forest in North and Central America, and Eurasia. From 300 isolates recovered from the gut of these beetles, 10 were selected to describe an ecotype of Rahnella contaminans. The polyphasic approach conducted with these isolates included phenotypic characteristics, fatty acid analysis, 16S rRNA gene, multilocus sequence analyses (gyrB, rpoB, infB, and atpD genes), and complete genome sequencing of two isolates, ChDrAdgB13 and JaDmexAd06, representative of the studied set. Phenotypic characterization, chemotaxonomic analysis, phylogenetic analyses of the 16S rRNA gene, and multilocus sequence analysis showed that these isolates belonged to Rahnella contaminans. The G + C content of the genome of ChDrAdgB13 (52.8%) and JaDmexAd06 (52.9%) was similar to those from other Rahnella species. The ANI between ChdrAdgB13 and JaDmexAd06 and Rahnella species including R. contaminans, varied from 84.02 to 99.18%. The phylogenomic analysis showed that both strains integrated a consistent and well-defined cluster, together with R. contaminans. A noteworthy observation is the presence of peritrichous flagella and fimbriae in the strains ChDrAdgB13 and JaDmexAd06. The in silico analysis of genes encoding the flagellar system of these strains and Rahnella species showed the presence of flag-1 primary system encoding peritrichous flagella, as well as fimbriae genes from the families type 1, α, β and σ mainly encoding chaperone/usher fimbriae and other uncharacterized families. All this evidence indicates that isolates from the gut of Dendroctonus-bark beetles are an ecotype of R. contaminans, which is dominant and persistent in all developmental stages of these bark beetles and one of the main members of their core gut bacteriome.
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Byers JA, Levi-Zada A. Modelling push-pull management of pest insects using repellents and attractive traps in fruit tree orchards. PEST MANAGEMENT SCIENCE 2022; 78:3630-3637. [PMID: 35598065 DOI: 10.1002/ps.7005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/18/2022] [Accepted: 05/21/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Push-pull with semiochemicals in pest management uses repellents to reduce response of pests to food-mate resources (push) and attractive traps to reduce populations (pull). Simulation models of push-pull can aid understanding of plant-insect interactions in nature and suggest hypotheses for field tests that improve management. A previous model indicated advantages of push-pull for controlling ambrosia beetle, Euwallacea fornicatus, pest of avocado trees. However, the simulated behavior of repellency was inconsistent with field observations. RESULTS We simulated individual-based movement of insects in push-pull to reveal relationships between parameters of radii (strength) of attractive traps, pest aggregations, and repellents with densities of each in an avocado orchard to visualize and understand the interactions and significance. Simulations indicated placement of traps along a 1-ha area periphery as a barrier resulted in similar trapping and mating as when traps were in a grid, either when insects originated randomly inside the plot or came from outside the plot. However, when insects originated from outside, both arrangements caught slightly more than when insects originated within the plot. CONCLUSION There were no differences in capture rates whether traps were spaced in a barrier along the plot's periphery or in a grid covering the plot. Push-pull was more effective than pull (mass trapping) alone. Repellent behavior of individuals when encountering a repellent radius was modelled by approximate 90° turns (right or left at random) when about to enter an infestation, consistent with earlier observations of effects of repellents on bark beetles orienting to aggregation pheromone. © 2022 Society of Chemical Industry.
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Bedoya CL, Nelson XJ, Brockerhoff EG, Pawson S, Hayes M. Experimental characterization and automatic identification of stridulatory sounds inside wood. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220217. [PMID: 35911201 PMCID: PMC9326298 DOI: 10.1098/rsos.220217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
The propagation of animal vocalizations in water and in air is a well-studied phenomenon, but sound produced by bark and wood-boring insects, which feed and reproduce inside trees, is poorly understood. Often being confined to the dark and chemically saturated habitat of wood, many bark- and woodborers have developed stridulatory mechanisms to communicate acoustically. Despite their ecological and economic importance and the unusual medium used for acoustic communication, very little is known about sound production in these insects, or their acoustic interactions inside trees. Here, we use bark beetles (Scolytinae) as a model system to study the effects of wooden tissue on the propagation of insect stridulations and propose algorithms for their automatic identification. We characterize distance dependence of the spectral parameters of stridulatory sounds, propose data-based models for the power decay of the stridulations in both outer and inner bark, provide optimal spectral ranges for stridulation detectability and develop automatic methods for their detection and identification. We also discuss the acoustic discernibility of species cohabitating the same log. The species tested can be acoustically identified with 99% of accuracy at distances up to 20 cm and detected to the greatest extent in the 2-6 kHz frequency band. Phloem was a better medium for sound transmission than bark.
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Chiu CC, Bohlmann J. Mountain Pine Beetle Epidemic: An Interplay of Terpenoids in Host Defense and Insect Pheromones. ANNUAL REVIEW OF PLANT BIOLOGY 2022; 73:475-494. [PMID: 35130442 DOI: 10.1146/annurev-arplant-070921-103617] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The mountain pine beetle epidemic has highlighted the complex interactions of bark beetles with conifer host defenses. In these interactions, oleoresin terpenoids and volatiles, produced and released by the host tree, can be both harmful and beneficial to the beetle's success in colonizing a tree and completing its life cycle. The insect spends almost its entire life, from egg to adult, within the bark and phloem of a pine host, exposed to large quantities of complex mixtures of oleoresin terpenoids. Conifer oleoresin comprises mostly monoterpenes and diterpene resin acids as well as many different sesquiterpenes. It functions as a major chemical and physical defense system. However, the insect has evolved host colonization behavior and enzymes for terpenoid metabolism and detoxification that allow it to overcome some of the terpenoid defenses and, importantly, to co-opt pine monoterpenes as cues for host search and as a precursor for its own pheromone system. The insect-associated microbiome also plays a role in the metabolism of conifer terpenoids.
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Zhang X, Li Y, Si H, Zhao G, Kolařík M, Hulcr J, Jiang X, Dai M, Chang R. Geosmithia Species Associated With Bark Beetles From China, With the Description of Nine New Species. Front Microbiol 2022; 13:820402. [PMID: 35369427 PMCID: PMC8964297 DOI: 10.3389/fmicb.2022.820402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/11/2022] [Indexed: 11/23/2022] Open
Abstract
Fungi of the genus Geosmithia are frequently associated with bark beetles that feed on phloem on various woody hosts. Most studies on Geosmithia were carried out in North and South America and Europe, with only two species being reported from Taiwan, China. This study aimed to investigate the diversity of Geosmithia species in China. Field surveys in Fujian, Guangdong, Guangxi, Hunan, Jiangsu, Jiangxi, Shandong, Shanghai, and Yunnan yielded a total of 178 Geosmithia isolates from 12 beetle species. The isolates were grouped based on morphology. The internal transcribed spacer, β-tubulin, and elongation factor 1-α gene regions of the representatives of each group were sequenced. Phylogenetic trees were constructed based on those sequences. In total, 12 species were identified, with three previously described species (Geosmithia xerotolerans, G. putterillii, and G. pallida) and nine new species which are described in this paper as G. luteobrunnea, G. radiata, G. brevistipitata, G. bombycina, G. granulata (Geosmithia sp. 20), G. subfulva, G. pulverea (G. sp. 3 and Geosmithia sp. 23), G. fusca, and G. pumila sp. nov. The dominant species obtained in this study were G. luteobrunnea and G. pulverea. This study systematically studied the Geosmithia species in China and made an important contribution to filling in the gaps in our understanding of global Geosmithia species diversity.
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Furniss TJ, Das AJ, van Mantgem PJ, Stephenson NL, Lutz JA. Crowding, climate, and the case for social distancing among trees. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2507. [PMID: 34870871 DOI: 10.1002/eap.2507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 06/25/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
In an emerging era of megadisturbance, bolstering forest resilience to wildfire, insects, and drought has become a central objective in many western forests. Climate has received considerable attention as a driver of these disturbances, but few studies have examined the complexities of climate-vegetation-disturbance interactions. Current strategies for creating resilient forests often rely on retrospective approaches, seeking to impart resilience by restoring historical conditions to contemporary landscapes, but historical conditions are becoming increasingly unattainable amidst modern bioclimatic conditions. What becomes an appropriate benchmark for resilience when we have novel forests, rapidly changing climate, and unprecedented disturbance regimes? We combined two longitudinal datasets-each representing some of the most comprehensive spatially explicit, annual tree mortality data in existence-in a post-hoc factorial design to examine the nonlinear relationships between fire, climate, forest spatial structure, and bark beetles. We found that while prefire drought elevated mortality risk, advantageous local neighborhoods could offset these effects. Surprisingly, mortality risk (Pm ) was higher in crowded local neighborhoods that burned in wet years (Pm = 42%) compared with sparse neighborhoods that burned during drought (Pm = 30%). Risk of beetle attack was also increased by drought, but lower conspecific crowding impeded the otherwise positive interaction between fire and beetle attack. Antecedent fire increased drought-related mortality over short timespans (<7 years) but reduced mortality over longer intervals. These results clarify interacting disturbance dynamics and provide a mechanistic underpinning for forest restoration strategies. Importantly, they demonstrate the potential for managed fire and silvicultural strategies to offset climate effects and bolster resilience to fire, beetles, and drought.
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Strullu-Derrien C, Philippe M, Kenrick P, Blanchette RA. Blue stain fungi infecting an 84-million-year-old conifer from South Africa. THE NEW PHYTOLOGIST 2022; 233:1032-1037. [PMID: 34743346 DOI: 10.1111/nph.17843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/28/2021] [Indexed: 06/13/2023]
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