scholarly journals Identification of Components of the Aggregation Pheromone of the Guam Strain of Coconut Rhinoceros Beetle, Oryctes rhinoceros, and Determination of Stereochemistry

2021 ◽  
Author(s):  
David R. Hall ◽  
Steven J. Harte ◽  
Dudley I. Farman ◽  
Mark Ero ◽  
Alfred Pokana
Keyword(s):  
Aggregation Pheromone ◽  
Solomon Islands ◽  
Field Trapping ◽  
Ethyl Esters ◽  
Male And Female ◽  
Tropical Asia ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
The Difference ◽  
Female Specific

AbstractThe coconut rhinoceros beetle, Oryctes rhinoceros (Linnaeus 1758) (Coleoptera: Scarabaeidae: Dynastinae) (CRB), is endemic to tropical Asia where it damages both coconut and oil palm. A new invasion by CRB occurred on Guam in 2007 and eradication attempts failed using commonly applied Oryctes rhinoceros nudivirus (OrNV) isolates. This and subsequent invasive outbreaks were found to have been caused by a previously unrecognized haplotype, CRB-G, which appeared to be tolerant to OrNV. The male-produced aggregation pheromone of the endemic, susceptible strain of O. rhinoceros (CRB-S) was previously identified as ethyl 4-methyloctanoate. Following reports from growers that commercial lures containing this compound were not attractive to CRB-G, the aim of this work was to identify the pheromone of CRB-G. Initial collections of volatiles from virgin male and female CRB-G adults from the Solomon Islands failed to show any male- or female-specific compounds as candidate pheromone components. Only after five months were significant quantities of ethyl 4-methyloctanoate and 4-methyloctanoic acid produced by males but not by females. No other male-specific compounds could be detected, in particular methyl 4-methyloctanoate, 4-methyl-1-octanol, or 4-methyl-1-octyl acetate, compounds identified in volatiles from some other species of Oryctes. Ethyl 4-methyloctanoate elicited a strong electroantennogram response from both male and female CRB-G, but these other compounds, including 4-methyloctanoic acid, did not. The enantiomers of ethyl 4-methyloctanoate and 4-methyloctanoic acid were conveniently prepared by enzymatic resolution of the commercially-available acid, and the enantiomers of the acid, but not the ester, could be separated by gas chromatography on an enantioselective cyclodextrin phase. Using this approach, both ethyl 4-methyloctanoate and 4-methyloctanoic acid produced by male CRB-G were shown to be exclusively the (R)-enantiomers whereas previous reports had suggested male O. rhinoceros produced the (S)-enantiomers. However, re-examination of the ester and acid produced by male CRB-S from Papua New Guinea showed that these were also the (R)-enantiomers. In field trapping experiments carried out in the Solomon Islands, both racemic and ethyl (R)-4-methyloctanoate were highly attractive to both male and female CRB-G beetles. The (S)-enantiomer and the corresponding acids were only weakly attractive. The addition of racemic 4-methyloctanoic acid to ethyl 4-methyloctanoate did significantly increase attractiveness, but the addition of (R)- or (S)-4-methyloctanoic acid to the corresponding ethyl esters did not. Possible reasons for the difference in assignment of configuration of the components of the CRB pheromone are discussed along with the practical implications of these results.

scholarly journals Aggregation Pheromone of the Guam Strain of Coconut Rhinoceros Beetle, Oryctes Rhinoceros, and Revision of Stereochemistry

2021 ◽  
Author(s):  
David R Hall ◽  
Steven J Harte ◽  
Dudley I Farman ◽  
Mark Ero ◽  
Alfred Pokana
Keyword(s):  
Aggregation Pheromone ◽  
Field Trapping ◽  
Ethyl Esters ◽  
Male And Female ◽  
Tropical Asia ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
Virgin Male ◽  
Female Specific ◽  
Male Specific

Abstract The coconut rhinoceros beetle, Oryctes rhinoceros (Linnaeus 1758) (Coleoptera: Scarabaeidae: Dynastinae) (CRB), is endemic to tropical Asia where it damages both coconut and oil palm. A new invasion by CRB occurred on Guam in 2007 and eradication attempts failed using commonly applied O. rhinoceros nudivirus (OrNV) isolates. This and subsequent invasive outbreaks were found to have been caused by a previously unrecognized haplotype, CRB-G, which appeared to be tolerant to OrNV. The male-produced aggregation pheromone of the endemic, susceptible strain of O. rhinoceros (CRB-S) was previously identified as ethyl 4-methyloctanoate. There were anecdotal reports that the commercial lures containing this compound were not attractive to CRB-G and the aim of this work was to identify the pheromone of CRB-G. Initial collections of volatiles from virgin male and female CRB-G adults failed to show any male- or female-specific compounds as candidate pheromone components. Only after five months were significant quantities of ethyl 4-methyloctanoate and 4-methyloctanoic acid produced by males but not by females. No other male-specific compounds could be detected, in particular methyl 4-methyloctanoate, 4-methyl-1-octanol or 4-methyl-1-octyl acetate, compounds identified in volatiles from some other species of Oryctes. Ethyl 4-methyloctanoate elicited a strong electroantennogram response from both male and female CRB-G, but these other compounds, including 4-methyloctanoic acid, did not. The enantiomers of ethyl 4-methyloctanoate and 4-methyloctanoic acid were conveniently prepared by enzymatic resolution of the commercially-available acid, and the enantiomers of the acid, but not the ester, could be separated by gas chromatography on an enantiospecific cyclodextrin phase. Using this approach, both the ethyl 4-methyloctanoate and the 4-methyloctanoic acid produced by male CRB-G were shown to be exclusively the (R)-enantiomers whereas previous reports had suggested male CRB-S produced the (S)-enantiomers. However, re-examination of the ester and acid produced by male CRB-S showed that these were also the (R)-enantiomers. In field trapping experiments, both racemic and ethyl (R)-4-methyloctanoate were highly attractive to both male and female CRB-G. The (S)-enantiomer and the corresponding acids were only weakly attractive. Addition of racemic 4-methyloctanoic acid to ethyl 4-methyloctanoate did significantly increase attractiveness, but addition of (R)- or (S)-4-methyloctanoic acid to the corresponding ethyl esters did not. Reasons for the previous misassignment of the configuration of the components of the CRB-S pheromone are discussed along with the practical implications of these results.

scholarly journals Male and Female Cervical Spine Biomechanics and Anatomy: Implication for Scaling Injury Criteria

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Narayan Yoganandan ◽  
Cameron R. Bass ◽  
Liming Voo ◽  
Frank A. Pintar
Keyword(s):  
Cervical Spine ◽  
Female Population ◽  
Male And Female ◽  
Injury Criteria ◽  
Motion Responses ◽  
Geometric Scaling ◽  
Biomechanical Responses ◽  
The Difference ◽  
Female Specific ◽  
The Military

There is an increased need to develop female-specific injury criteria and anthropomorphic test devices (dummies) for military and automotive environments, especially as women take occupational roles traditionally reserved for men. Although some exhaustive reviews on the biomechanics and injuries of the human spine have appeared in clinical and bioengineering literatures, focus has been largely ignored on the difference between male and female cervical spine responses and characteristics. Current neck injury criteria for automotive dummies for assessing crashworthiness and occupant safety are obtained from animal and human cadaver experiments, computational modeling, and human volunteer studies. They are also used in the military. Since the average human female spines are smaller than average male spines, metrics specific to the female population may be derived using simple geometric scaling, based on the assumption that male and female spines are geometrically scalable. However, as described in this technical brief, studies have shown that the biomechanical responses between males and females do not obey strict geometric similitude. Anatomical differences in terms of the structural component geometry are also different between the two cervical spines. Postural, physiological, and motion responses under automotive scenarios are also different. This technical brief, focused on such nonuniform differences, underscores the need to conduct female spine-specific evaluations/experiments to derive injury criteria for this important group of the population.

scholarly journals Genomic structural and transcriptional variation of Oryctes rhinoceros nudivirus (OrNV) in Coconut Rhinoceros Beetle

2020 ◽  
Author(s):  
Kayvan Etebari ◽  
Rhys Parry ◽  
Marie Joy B. Beltran ◽  
Michael J. Furlong
Keyword(s):  
Gene Expression ◽  
Solomon Islands ◽  
Dna Helicase ◽  
The Philippines ◽  
Comparative Genomic ◽  
Viral Gene ◽  
Geographic Population ◽  
Oryctes Rhinoceros ◽  
Synonymous Mutations ◽  
Rhinoceros Beetle

AbstractOryctes rhinoceros nudivirus (OrNV) is a large circular double-stranded DNA virus which has been used as a biological control agent to suppress Coconut Rhinoceros Beetle (Oryctes rhinoceros) in Southeast Asia and the Pacific Islands. Recently a new wave of O. rhinoceros incursions in Oceania in previously non-infested areas is thought to be related to the presence of low virulence isolates of OrNV or virus tolerant haplotypes of beetles. In this study, chronically infected O. rhinoceros adults were field collected from the Philippines, Fiji, Papua New Guinea and the Solomon Islands. We extracted total RNA from these samples to investigate the global viral gene expression profiles and comparative genomic analysis of structural variations between the four different populations. Maximum likelihood phylogenic analysis indicated that OrNV strains from the Solomon Islands and the Philippines are closely related to while OrNV strains from PNG and Fiji formed a distinct adjacent clade. We detected several polymorphic sites with a frequency higher than 35% in 892 positions of the viral genome. The highest number of structural variants, including single nucleotide variants (SNV), insertion, deletion and non-synonymous mutations, were found in strains from Fiji and PNG when compared to complete recently sequenced Solomon Islands OrNV reference genome. Non-synonymous mutations were detected in several hypothetical proteins, and 15 nudivirus core genes such as OrNV_gp034 (DNA Helicase), lef-8, lef-4 and vp91. For examination of the global gene expression profile of OrNV in chronically infected populations, we found limited evidence of variation between geographic populations. Only a few genes such as OrNV_gp01 (DNA polymerase B), OrNV_gp022 and OrNV_gp107 (Pif-3) were differentially expressed among different strains. Additionally, small RNA sequencing from the Solomon Islands population suggests that OrNV is targeted by the host RNA interference (RNAi) response with abundant 21nt small RNAs. Additionally, we identified a highly abundant putative 22 nt miRNA from the 3’ of a pre-miRNA-like hairpin originating from OrNV-gp-098. These findings provide valuable resources for future studies to improve our understanding of the OrNV genetic variation. Some of these structural changes are specific to the geographic population and could be related to particular phenotypic characteristics of the strain, such as viral pathogenicity or transmissibility, and this requires further investigation.

scholarly journals Genetic structure of the Coconut Rhinoceros Beetle (Oryctes rhinoceros) population and the incidence of its biocontrol agent (Oryctes rhinoceros nudivirus) in the South Pacific Islands

2020 ◽  
Author(s):  
Kayvan Etebari ◽  
James Hereward ◽  
Apenisa Sailo ◽  
Emeline M Ahoafi ◽  
Robert Tautua ◽  
...  
Keyword(s):  
Biocontrol Agent ◽  
New Caledonia ◽  
Solomon Islands ◽  
South Pacific ◽  
The Philippines ◽  
Mitochondrial Lineage ◽  
The South ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
The Pacific

Incursions of the Coconut rhinoceros beetle (CRB), Oryctes rhinoceros, have been detected in several countries of the south-west Pacific in recent years, resulting in an expansion of the pest's geographic range. It has been suggested that this resurgence is related to an O. rhinoceros mitochondrial lineage (previously referred to as the CRB-G biotype) that is reported to show reduced susceptibility to the well-established classical biocontrol agent, Oryctes rhinoceros nudivirus (OrNV). We investigated O. rhinoceros population genetics and the OrNV status of adult specimens collected in the Philippines and seven different South Pacific island countries (Fiji, New Caledonia, Papua New Guinea (PNG), Samoa, Solomon Islands, Tonga, and Vanuatu). Based on the presence of single nucleotide polymorphisms (snps) in the mitochondrial Cytochrome C Oxidase subunit I (CoxI) gene, we found three major mitochondrial lineages (CRB-G, a PNG lineage (CRB-PNG) and the South Pacific lineage (CRB-S)) across the region. Haplotype diversity varied considerably between and within countries. The O. rhinoceros population in most countries was monotypic and all individuals tested belonged to a single mitochondrial lineage (Fiji, CRB-S; Tonga, CRB-S; Vanuatu, CRB-PNG; PNG (Kimbe), CRB-PNG; New Caledonia CRB-G; Philippines, CRB-G). However, in Samoa we detected CRB-S and CRB-PNG and in Solomon Islands we detected all three haplotype groups. Genotyping-by-Sequencing (GBS) methods were used to genotype 10,000 snps from 230 insects across the Pacific and showed genetic differentiation in the O. rhinoceros nuclear genome among different geographical populations. The GBS data also provided evidence for gene flow and admixture between different haplotypes in Solomon Islands. Therefore, contrary to earlier reports, CRB-G is not solely responsible for damage to the coconut palms reported since the pest was first recorded in Solomon Islands in 2015. We also PCR-screened a fragment of OrNV from 260 insects and detected an extremely high prevalence of viral infection in all three haplotypes in the region. We conclude that the haplotype groups CRB-G, CRB-S, and PNG, do not represent biotypes, subspecies, or cryptic species, but simply represent different invasions of O. rhinoceros across the Pacific. This has important implications for management, especially biological control, of Coconut rhinoceros beetle in the region.

scholarly journals Transcriptome and microbiome of coconut rhinoceros beetle (Oryctes rhinoceros) larvae

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Matan Shelomi ◽  
Shih-Shun Lin ◽  
Li-Yu Liu
Keyword(s):  
Pacific Islands ◽  
Plant Cell Wall ◽  
Fat Body ◽  
Molecular Data ◽  
Cell Wall Degrading Enzymes ◽  
Tropical Asia ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
Microbial Symbionts ◽  
Decaying Wood

Abstract Background The coconut rhinoceros beetle, Oryctes rhinoceros, is a major pest of palm crops in tropical Asia and the Pacific Islands. Little molecular data exists for this pest, impeding our ability to develop effective countermeasures and deal with the species’ growing resistance to viral biocontrols. We present the first molecular biology analyses of this species, including a metagenomic assay to understand the microbiome of different sections of its digestive tract, and a transcriptomics assay to complement the microbiome data and to shed light on genes of interest like plant cell wall degrading enzymes and immunity and xenobiotic resistance genes. Results The gut microbiota of Oryctes rhinoceros larvae is quite similar to that of the termite gut, as both species feed on decaying wood. We found the first evidence for endogenous beta-1,4-endoglucanase in the beetle, plus evidence for microbial cellobiase, suggesting the beetle can degrade cellulose together with its gut microfauna. A number of antimicrobial peptides are expressed, particularly by the fat body but also by the midgut and hindgut. Conclusions This transcriptome provides a wealth of data about the species’ defense against chemical and biological threats, has uncovered several potentially new species of microbial symbionts, and significantly expands our knowledge about this pest.

scholarly journals Aggregation pheromone of coconut rhinoceros beetle,Oryctes rhinoceros (L.) (coleoptera: Scarabaeidae)

1995 ◽  
Vol 21 (10) ◽  
pp. 1549-1570 ◽  
Author(s):  
Rebecca H. Hallett ◽  
Alice L. Perez ◽  
Gerhard Gries ◽  
Regine Gries ◽  
Harold D. Pierce ◽  
...  
Keyword(s):  
Aggregation Pheromone ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle

scholarly journals Complete genome sequence of Oryctes rhinoceros nudivirus isolated from the coconut rhinoceros beetle in Solomon Islands

2020 ◽  
Vol 278 ◽  
pp. 197864 ◽  
Author(s):  
Kayvan Etebari ◽  
Igor Filipović ◽  
Gordana Rašić ◽  
Gregor J. Devine ◽  
Helen Tsatsia ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Solomon Islands ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle

scholarly journals Complete genome sequence of Oryctes rhinoceros Nudivirus isolated from Coconut Rhinoceros Beetle in the Solomon Islands

2019 ◽  
Author(s):  
Kayvan Etebari ◽  
Igor Filipović ◽  
Gordana Rašić ◽  
Gregor J. Devine ◽  
Helen Tsatsia ◽  
...  
Keyword(s):  
Genome Sequence ◽  
Genomic Sequence ◽  
Solomon Islands ◽  
Insect Pest ◽  
Open Reading Frames ◽  
Full Genome Sequence ◽  
Oryctes Rhinoceros ◽  
Rhinoceros Beetle ◽  
Oxford Nanopore ◽  
Long Read

AbstractOryctes Nudivirus (OrNV) has been an effective biocontrol agent against the insect pest Oryctes rhinoceros (Coleoptera: Scarabaeidae) for decades, but there is evidence that resistance could be evolving in some host populations. We detected OrNv infection in O. rhinoceros from the Solomon Islands and used Oxford Nanopore Technologies (ONT) long-read sequencing to determine the full length of the virus genomic sequence isolated from an individual belonging to a mitochondrial lineage (CRB-G) that was previously reported as resistant to OrNV. The complete circular genome of the virus consisted of 125,917 nucleotides, encoding 130 open reading frames (ORFs) for proteins in the range ~5 kDa (51aa) to ~140 kDa (1280aa). This Solomon Islands isolate has high (99.85%) nucleotide sequence identity to the previously sequenced isolate PV505 from Southern Luzon, Philippines, and has 138 amino acid modifications when compared with the originally described full genome sequence of the Ma07 strain from Malaysia.

Perceived social support and burden of care of male and female caregivers of patient with schizophrenia

2017 ◽  
Vol 8 (1) ◽  
pp. 10
Author(s):  
Narendra Kumar Singh ◽  
Nishant Goyal
Keyword(s):  
Social Support ◽  
Perceived Social Support ◽  
Family Members ◽  
Well Being ◽  
Cross Sectional Study ◽  
Burden Of Care ◽  
Cross Sectional ◽  
Male And Female ◽  
The Social ◽  
The Difference

Background: Schizophrenia is associated with a high familial, social and economic burden. Schizophrenia is also associated with a high level of disability which may create impediments on the social and economic areas of the patients as well as on their respective family networks. Families with schizophrenia may encounter problems such as impairment of health and well being of other family members, restriction of social activities of the family members and shrinking of support from the social network. Aims: The present study examined the difference in perceived social support and burden of care between the male and female caregivers of patients with schizophrenia. Methods: This was a cross-sectional study examining the difference in perceived social support and burden of care between the male and female caregivers of patients with schizophrenia. The sample consisted of 60 (30 male and 30 female) caregivers of the patients with the diagnosis of schizophrenia as per ICD-10-DCR. Results and Conclusion: This study revealed that male caregivers perceived more social support and less burden of care as compared to female caregivers. Key words: Gender, social support, burden

Sign in / Sign up

Export Citation Format

Share Document