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Environmental Entomology Dec 2023Laurel wilt disease (LWD) is a lethal vascular wilt caused by an exotic ambrosia beetle-fungal complex, the redbay ambrosia beetle, Xyleborus glabratus Eichhoff, and its...
Laurel wilt disease (LWD) is a lethal vascular wilt caused by an exotic ambrosia beetle-fungal complex, the redbay ambrosia beetle, Xyleborus glabratus Eichhoff, and its nutritional symbiont, Harringtonia lauricola (Harr., Fraedrich & Aghayeva) de Beer & Procter. LWD is responsible for the widespread mortality of redbay, Persea borbonia (L.) Spreng., devastating coastal forests in the southeast United States. More recently, LWD is causing mortality of understory sassafras, Sassafras albidum (Nutt.) Nees, in deciduous forests in Kentucky, USA; the biology, epidemiology, and long-term impacts of LWD in deciduous forests are unclear. All North American lauraceous species evaluated have shown susceptibility, and numerous additional ambrosia beetles have demonstrated vector potential, but no studies to date have assessed the presence of H. lauricola in other insects associated with LWD-infected sassafras. We sampled infected sassafras from the leading edge of the LWD range and collected insect associates to evaluate phoretic and internal presence of H. lauricola. We recorded 118 individuals of 38 morphospecies emerging; most were Coleoptera. Of the 48 specimens evaluated for H. lauricola, none tested positive for phoretic presence, but internal presence was evident in the granulate ambrosia beetle, Xylosandrus crassiusculus Motschulsky, and in a hidden snout weevil, Apteromechus ferratus Say. This is the first report of H. lauricola associated with a non-ambrosia beetle and expands our understanding of the vector potential of additional insect species while confirming the role of the granulate ambrosia beetle. These findings contribute to our understanding of LWD epidemiology in sassafras hosts from more northerly latitudes.
Topics: Animals; Sassafras; Coleoptera; Weevils; Persea
PubMed: 37738471
DOI: 10.1093/ee/nvad099 -
Journal of Economic Entomology Dec 2023Knowledge of specialty crop cultivars with resistance against insect pests is limited, and this may serve as a barrier to implementing host-plant resistance as part of...
Knowledge of specialty crop cultivars with resistance against insect pests is limited, and this may serve as a barrier to implementing host-plant resistance as part of an integrated pest management strategy. Carrot (Daucus carota L.) (Apiaels: Apiaceae)is a valuable specialty crop with a diversity of insect pests and cultivars that differ in physical and chemical qualities that influence insect pest preferences. To investigate the role of cultivar as a tool to reduce insect pest damage, we evaluated 7 carrot cultivars in replicated laboratory and field trials in IN and OH, USA in 2021. During June and July, we documented oviposition and feeding damage by the carrot weevil (Listronotus oregonenesis LeConte) (Coleoptera: Curculionidae) and used faunistic analysis to measure the abundance and diversity of foliar insect assemblages on each cultivar. We found no significant differences in oviposition and root damage across cultivars in the field, with mean cumulative egg scars ranging from 1.83 ± 1.40 in "Red Core Chantenay" to 5.17 ± 2.62 in "Cosmic Purple". However, there was a positive correlation between the cumulative number of egg scars and number of trichomes on petioles. Similarly, no-choice laboratory bioassays revealed no significant differences in mean cumulative egg scars, ranging from 5.00 ± 1.15 in "Red Core Chantenay" to 10.63 ± 1.02 in "Danvers 126". Predominant insect pests differed across cultivars, but Cicadellidae was common across all cultivars. Interestingly, only 1 beneficial insect family, Pteromalidae, was predominant across cultivars. This research highlights the impact of cultivar selection on the diversity and damage potential of insect pests in carrot production.
Topics: Animals; Coleoptera; Weevils; Daucus carota; Cicatrix
PubMed: 37903057
DOI: 10.1093/jee/toad196 -
Neotropical Entomology Oct 2023Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) parasitizes the diamond back moth Plutella xylostella (L.) (Lepidoptera: Plutellidae), but not much is known...
Olfaction Response and Fertility Life Table Parameters of Tetrastichus howardi (Hymenoptera: Eulophidae) Parasitizing Plutella xylostella (Lepidoptera: Plutellidae) and the factitious host Tenebrio molitor (Coleoptera: Tenebrionidae).
Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) parasitizes the diamond back moth Plutella xylostella (L.) (Lepidoptera: Plutellidae), but not much is known about its potential as a biocontrol agent. A rearing protocol has been established for this parasitoid on pupae of the factitious host Tenebrio molitor (L.) (Coleoptera: Tenebrionidae), with the aim of releasing it in the field to manage several lepidopteran species. The potential population growth of a parasitoid can be measured through fertility life tables and provide supporting information for using T. howardi in the management of P. xylostella. Also, the fitness and behavior of T. howardi reared on a factitious host can be indicators of its potential to control P. xylostella. Thus, in this study, the fertility life table parameters of T. howardi parasitizing P. xylostella were determined, as well as the effects of the natal host on the behavior of T. howardi towards host volatiles and parasitism rate. The results showed that net reproduction rate (R) and the intrinsic rate of population growth (r) of T. howardi parasitizing P. xylostella were 13.6 (♀/♀) and 0.124 (♀/♀*day), respectively, whereas the mean generation time was 20.9 days. Moreover, the natal host (T. molitor or P. xylostella) did not affect the fitness, parasitism rate, or olfactory response of T. howardi. In general, regardless of the natal host, parasitoid females responded to volatiles of both host species and exhibited the same rate of parasitism on P. xylostella. Therefore, T. howardi reared on the factitious host maintains its attraction and potential to parasitize P. xylostella, and can contribute to the biological control of this pest.
Topics: Female; Animals; Hymenoptera; Tenebrio; Coleoptera; Life Tables; Smell; Moths; Fertility; Larva
PubMed: 37584879
DOI: 10.1007/s13744-023-01068-8 -
Bioorganic Chemistry Dec 2023Blapspirooxindoles A-C (1-3), three novel spirooxindole alkaloids with a unique spiro[chromane-4,3'-indoline]-2,2'-dione motif, blapcumaranons A and B (4 and 5), two new...
Blapspirooxindoles A-C (1-3), three novel spirooxindole alkaloids with a unique spiro[chromane-4,3'-indoline]-2,2'-dione motif, blapcumaranons A and B (4 and 5), two new 2-cumaranon derivatives, blapoxindoles A-J (6-15), ten new oxindole alkaloid derivatives, along with one known compound (16), were isolated from the whole bodies of Blaps japanensis. Their structures including absolute configurations were determined by using spectroscopic, X-ray crystallographic, and computational methods. Compounds 1-11 and 13 exist as racemic mixtures in nature, and their (-)- and (+)-antipodes were separated by chiral HPLC. Biological evaluations of these compounds were determined with multiple assays including anti-tumor, anti-inflammatory, and renal protection activities in vitro. Several compounds displayed effective activity in one or more assays.
Topics: Animals; Coleoptera; Antineoplastic Agents; Alkaloids; Neoplasms; Oxindoles; Molecular Structure
PubMed: 37797453
DOI: 10.1016/j.bioorg.2023.106845 -
PloS One 2023Bark beetle infestations have historically been primary drivers of stand thinning in Mexican pine forests. However, bark beetle impacts have become increasingly...
Abundance of Dendroctonus frontalis and D. mexicanus (Coleoptera: Scolytinae) along altitudinal transects in Mexico: Implications of climatic change for forest conservation.
Bark beetle infestations have historically been primary drivers of stand thinning in Mexican pine forests. However, bark beetle impacts have become increasingly extensive and intense, apparently associated with climate change. Our objective was to describe the possible association between abundance of bark beetle flying populations and the occurrence of given value intervals of temperature, precipitation and their balance, in order to have a better comprehension of the climatic space that might trigger larger insect abundances, an issue relevant in the context of the ongoing climatic change. Here, we monitored the abundance of two of the most important bark beetle species in Mexico, Dendroctonus frontalis and D. mexicanus. We sampled 147 sites using pheromone-baited funnel traps along 24 altitudinal transects in 11 Mexican states, from northwestern Chihuahua to southeastern Chiapas, from 2015 to 2017. Through mixed model analysis, we found that the optimum Mean Annual Temperatures were 17°C-20°C for D. frontalis in low-elevation pine-oak forest, while D. mexicanus had two optimal intervals: 11-13°C and 15-18°C. Higher atmospheric Vapor Pressure Deficit (≥ 1.0) was correlated with higher D. frontalis abundances, indicating that warming-amplified drought stress intensifies trees' vulnerability to beetle attack. As temperatures and drought stress increase further with projected future climatic changes, it is likely that these Dendroctonus species will increase tree damage at higher elevations. Pine forests in Mexico are an important source of livelihood for communities inhabiting those areas, so providing tools to tackle obstacles to forest growth and health posed by changing climate is imperative.
Topics: Animals; Coleoptera; Mexico; Conservation of Natural Resources; Weevils; Forests; Pinus; Trees
PubMed: 37405993
DOI: 10.1371/journal.pone.0288067 -
Pesticide Biochemistry and Physiology Aug 2023Overcoming the innate immunity of insects is a key process to improve the efficiency of biological control. Antimicrobial peptides (AMPs) are important effectors in...
Overcoming the innate immunity of insects is a key process to improve the efficiency of biological control. Antimicrobial peptides (AMPs) are important effectors in insect innate immunity, usually mediating resistance to pathogenic microorganisms through Toll and IMD signaling pathways. This study investigated the effect of key genes on upstream immune recognition receptor (GNBP) and downstream effectors (AMPs) by RNAi technology. The transcriptome KEGG enrichment analysis and differential gene annotation results showed that the immune response genes MaltSpz and MaltRelish are important regulators of Toll and IMD signaling pathways, respectively. Both dsSpz and dsRelish could affect AMP gene expression and increase the expression of the immune recognition receptor MaltGNBP. Moreover, they significantly reduce the survival rate of Monochamus alternatus and promote hyphal growth after Beauveria bassiana infection. This helps to improve the biological control effect of B. bassiana, control the population of vector insects and cut off the transmission route of pine wood nematode. The combined MaltSpz and MaltRelish knockdown increased the infection rate of M. alternatus larvae from 20.69% to 83.93%, achieving the best efficiency in synergistic B. bassiana infection. Our results showed important roles of MaltRelish- and MaltSpz-mediated regulation of AMP genes function in insect entomopathogenic fungi tolerance and induced significant mortality in larvae. Based on this study, MaltSpz and MaltRelish could represent candidate gene targets for the biological control of M. alternatus by RNAi.
Topics: Animals; Coleoptera; Larva; Pest Control; Gene Expression Profiling; Beauveria
PubMed: 37532354
DOI: 10.1016/j.pestbp.2023.105495 -
Pest Management Science Dec 2023Monochamus carolinensis is an important vector of pinewood nematodes in North America that is under quarantine in several countries worldwide. The distribution of...
BACKGROUND
Monochamus carolinensis is an important vector of pinewood nematodes in North America that is under quarantine in several countries worldwide. The distribution of M. carolinensis was previously thought to be limited to North America; however, we discovered it during trapping in China in 2022. Using this discovery and information regarding the area of origin, we applied a machine-learning algorithm based on the maximum entropy principle to predict the current and future (2050s, 2070s) potential distribution areas of M. carolinensis using bioclimatic variables.
RESULTS
The biological suitability of M. carolinensis was mainly driven by precipitation factors (BIO18, BIO15, BIO19), with 87.18% of the potential distribution areas located in South America, Asia, North America and Africa. Future potential distribution areas of M. carolinensis are predicted to expand to high latitudes, with an average increase of 10 245 874.88 km , and only 6.89% of the current suitable areas will become unsuitable. The potential distribution areas in 2070 are largest under the SSP585 scenario, with a 41.40% predicted increase (52 309 803.61 km ) above the current distribution, mainly reflecting an increase of the marginally and highly suitable areas.
CONCLUSION
The determination of dominant climatic factors and potential distribution areas will help provide an early warning for an M. carolinensis invasion, as well as provide a scientific basis for the spread and outbreak, facilitating development of effective governmental prevention and control measures. © 2023 Society of Chemical Industry.
Topics: Animals; Climate Change; Coleoptera; Entropy; China; North America
PubMed: 37656761
DOI: 10.1002/ps.7753 -
Food Chemistry Jul 2024The present work aimed to quantify the macronutrients and the fatty acid (FA) profile in different killing methods, blanching (BC) and freezing (FR), on edible insects...
The present work aimed to quantify the macronutrients and the fatty acid (FA) profile in different killing methods, blanching (BC) and freezing (FR), on edible insects of the speciesTenebrio molitor(TM) andZophobas morio(ZM). Concerning macronutrients TM-BC and TM-FR presented 51.2% and 50.6% of protein, 28% and 29.4% of lipids, and 12.4% and 11.4%. Meanwhile, ZM-BC and ZM-FR expressed 42.8% and 43.7% of protein, 39.1% and 40.1% of lipids, and 10.7% and 8.9% of carbohydrates. The FA of TM and ZM shows respectively values of Saturated Fatty Acids (∑SFA) 30% - 45%, Monounsaturated (MUFA) 47% - 32%, Polyunsaturated (∑PUFA) 23% - 22%, Atherogenicity Index (AI) 0.64 - 0.75, Thrombogenicity Index (TI) 0.77 - 1.44 and hypocholesterolemic/hypercholesterolemic index (h/H) of 2.50-1.51. Based on the results obtained, the slaughter methods showed statistically differences in relation to MUFA's in TM, and ZM larvae only in the minority fraction of FA.
Topics: Animals; Tenebrio; Fatty Acids; Coleoptera; Larva; Edible Insects
PubMed: 38401309
DOI: 10.1016/j.foodchem.2024.138719 -
PloS One 2023Cantharidin (CTD) is a well-established defensive toxin synthesized by blister beetles, displaying both therapeutic potential and toxicity. Among these beetles, Hycleus...
Cantharidin (CTD) is a well-established defensive toxin synthesized by blister beetles, displaying both therapeutic potential and toxicity. Among these beetles, Hycleus cichorii and Hycleus phaleratus are the two most commercially significant species due to their capacity to produce CTD in males. In this investigation, we conducted a gene expression profiling analysis of male and female individuals of these two species, utilizing the Illumina Hiseq4000 platform. We identified 7,983 expressed genes, including 2,823 differentially expressed genes (DEGs) shared by both male and female blister beetles. Nineteen genes related to CTD biosynthesis in the terpenoid backbone biosynthesis pathway were identified, including hydroxymethylglutaryl-CoA reductase (HMGR; EC:1.1.1.34), which demonstrated a significant correlation with CTD content. Furthermore, hydroxymethylglutaryl-CoA synthase (HMGS; EC:2.3.3.10) and isopentenyl-diphosphate Delta-isomerase (IDI; EC:5.3.3.2) were also found to be significantly up-regulated in males. Comparative analysis revealed that NADP+-dependent farnesol dehydrogenase (FOHSDR; EC:1.1.1.216) and farnesyl diphosphate synthase (FDPS; EC:2.5.1.1) had the highest copy number in these beetles, significantly higher than the copy number of the other four non-Meloidae insects. The analysis of the protein-protein interaction network of genes related to CTD biosynthesis revealed that the acetyl-CoA C-acetyltransferase (ACAT; EC:2.3.1.9) gene was the central gene, exhibiting greater expression in male blister beetles than in females. This study offers novel insights into the mechanisms of CTD biosynthesis in blister beetles and enhances our comprehensions of the association between particular genes and CTD content.
Topics: Female; Male; Animals; Cantharidin; Coleoptera; Acetyl-CoA C-Acetyltransferase; Farnesol; Gene Expression Profiling
PubMed: 37594933
DOI: 10.1371/journal.pone.0290245 -
PloS One 2024Urban trees are at risk of stress due to heat island effects and the increased proportion of impervious areas surrounding them. Among pests of trees, insect borers such...
Urban trees are at risk of stress due to heat island effects and the increased proportion of impervious areas surrounding them. Among pests of trees, insect borers such as bark beetles (Coleoptera: Curculionidae) and flatheaded borers (Coleoptera: Buprestidae) are some of the most devastating, frequently colonizing stressed trees. The objective of this study was to explore the effects of biotic and abiotic risk factors on borer attacks on trees in urban areas. In the summer of 2021 and 2022, this study was conducted in 50 urban sites in Atlanta and Augusta, Georgia (USA). Specific factors explored include overall tree health, differentially warmer maximum and minimum temperatures of sites compared to surrounding areas, tree species, and the percentage of impervious surface surrounding trees. Generalized linear models and zero-inflated models explored how these factors were related to damage from these borers. The number of borer attacks on trees increased with higher percentage impervious area. As the two most commonly encountered trees, Acer rubrum was found to be significantly more susceptible to attack from borers than Ulmus parvifolia. Unhealthy trees were more likely to experience more frequent and more severe borer attack. Trees with increased impervious cover around them as well as those with differentially warmer daily maximum and minimum temperatures relative to surrounding were more likely to be attacked.
Topics: Animals; Cities; Georgia; Hot Temperature; Insecta; Coleoptera; Trees; Weevils; Risk Factors
PubMed: 38408102
DOI: 10.1371/journal.pone.0299368