Monitoring an invasive coconut rhinoceros beetle population using pheromone traps in Honiara, Solomon Islands

An invasive population of the coconut rhinoceros beetle (Oryctes rhinoceros; CRB) was discovered in Honiara, Guadalcanal, Solomon Islands in 2015. The beetle has caused severe damage to coconut palms in the outbreak area and its continued spread threatens the food security and livelihood of thousands of smallholder farmers in the region. Spread and abundance of the beetle were monitored using bucket traps baited with the aggregation pheromone, ethyl-4 methyloctanoate. Beetles were collected from traps approximately bi-weekly for two periods; one during 2017–18 and the other during 2019–2020. Trap catches showed that CRB was present throughout the whole survey region with significantly higher numbers of female CRB trapped than males. Results indicate a significant 1.5-fold increase in CRB trap catch numbers from 2017–2018 to 2019–2020 despite control efforts. The number of CRB adults trapped also varied between sites and months during both time periods but with no clear patterns. Removal of breeding sites along with strong local quarantine should remain the top priority of the local government to contain CRB expansion within Solomon Islands and beyond.

Download Full-text

Trap catches of the coconut rhinoceros beetle Oryctes rhinoceros (L.) (Coleoptera, Scarabaeidae, Dynastinae) in New Britain

Bulletin of Entomological Research ◽

10.1017/s0007485300006118 ◽

1975 ◽

Vol 65 (3) ◽

pp. 443-451 ◽

Cited By ~ 5

Author(s):

G. O. Bedford

Keyword(s):

Heavy Rain ◽

Initial Population ◽

Breeding Sites ◽

Oryctes Rhinoceros ◽

Rhinoceros Beetle ◽

Gradual Disappearance ◽

Trap Catches ◽

New Britain ◽

High Rainfall Area

AbstractThe trend in the relative populations of Oryctes rhinoceros (L.) in two areas of the Gazelle Peninsula, New Britain, was studied by trapping adults searching for breeding sites. In a high rainfall area with 10-year-old palms and many possible breeding sites, there was a large initial population of beetles which declined over the next three years with the gradual disappearance of the breeding sites; weekly catches were higher when the undergrowth in the trapping area was slashed, and to some extent also at new moon; catches were depressed by heavy rain. The ♂/♂ sex ratio was 0·31; all females had mated and had mature eggs in the lower ends of the oviducts. These results were compared with those from a low rainfall area with 70-year-old palms and dispersed breeding sites. Catches were generally lower; they showed no long term trend and were not related to slashing or weekly rainfall, but were inversely related to the number of rainy days per week.

Download Full-text

The distribution of Culex mosquitoes in Coimbatore, Tamil Nadu, India

Journal of Entomological and Acarological Research ◽

10.4081/jear.2015.4565 ◽

2015 ◽

Vol 47 (1) ◽

pp. 1

Author(s):

A. Naresh Kumar ◽

K. Murugan ◽

C. Thomas Vincent ◽

P. Madhiyazhagan ◽

T. Nataraj ◽

...

Keyword(s):

Tamil Nadu ◽

Mosquito Control ◽

Lymphatic Vessels ◽

Wuchereria Bancrofti ◽

Severe Damage ◽

Breeding Sites ◽

Ecological Changes ◽

Mapping System ◽

Coimbatore District ◽

Vector Distribution

Lymphatic filariasis is an infection with the filarial worms, Wuchereria bancrofti, Brugia malayi and B. timori. These parasites are transmitted to humans through the bite of an infected Culex mosquito and develop into adult worms in the lymphatic vessels, causing severe damage and swelling (lymphoedema). Mosquito control, in view of their medical as well as economical importance, assumes global importance. Geographic information system (GIS) is a powerful tool to analyse the distribution of mosquitoes and their relationship to different environmental factors, and can substantially improve our ability to quantify the impacts of demographic, climatic and ecological changes in vector distribution. In the present study Culex quinquefasciatus, Culex tritaeniorhynchus and Culex gelidus were recorded in the study area. Few other factors such as larval mosquito density, number of breeding sites, human population, etc. were also analysed for its impact on the distribution of Culex mosquitoes. Distribution of Culex in the present study affirmed that C. quinquefasciatus is predominant in the entire focal area, which explains the behavioural response and capability of the species in varied zones. Information gathered from this study is being used to construct a GIS-based mapping system for distribution of Culex mosquitoes in the Coimbatore District, Tamil Nadu, India.

Download Full-text

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

10.1101/2020.05.27.119867 ◽

2020 ◽

Cited By ~ 1

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.

Download Full-text

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

10.1101/2020.07.30.229872 ◽

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.

Download Full-text

The Brown Marmorated Stink Bug (Halyomorpha halys Stål.) Influences Pungent and Non-Pungent Capsicum cultivars’ Pre- and Post-Harvest Quality

Agronomy ◽

10.3390/agronomy11112252 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2252

Author(s):

Tilen Zamljen ◽

Robert Veberic ◽

Metka Hudina ◽

Ana Slatnar

Keyword(s):

Fruits And Vegetables ◽

Metabolic Response ◽

Fold Increase ◽

Invasive Pest ◽

Halyomorpha Halys ◽

Stink Bug ◽

Severe Damage ◽

Post Harvest ◽

Entire Plant

Halyomorpha halys is an important invasive pest that causes severe damage to fruits and vegetables. Peppers are susceptible to infestation by H. halys, resulting in yield losses. Plants respond to the insect infestation with a metabolic response. With this study, we attempted to determine the intensity of the metabolic response of infested peppers, how pungent and non-pungent peppers react to the infestation, and how the H. halys affects the post-harvest quality of both cultivars. The shelf life of the infested peppers did not change compared to the control treatments. We observed a drastic decrease in metabolite levels after storage in all three treatments in both cultivars, especially capsaicinoids, with an approximate decrease of 30% in the pericarp and 95% in the placenta of the pungent ‘Eris F1’. In some cases, the accumulation of metabolites was not limited to the fruit exposed to the H. halys infestation, but to the entire plant. We observed a 15-fold increase in capsaicinoid content in the infested fruits of cultivar ‘Eris F1’ and a 4-fold increase in the pericarp of cultivar ‘Lombardo tago’, which could lead to a possible further study on the defensive function of capsaicinoids and their use against H. halys.

Download Full-text

Oviposition Preferences and Behavior of Wild-Caught and Laboratory-Reared Coconut Rhinoceros Beetle, Oryctes rhinoceros (Coleoptera: Scarabaeidae), in Relation to Substrate Particle Size

Insects ◽

10.3390/insects9040141 ◽

2018 ◽

Vol 9 (4) ◽

pp. 141 ◽

Cited By ~ 1

Author(s):

Megan Manley ◽

Michael Melzer ◽

Helen Spafford

Keyword(s):

Particle Size ◽

Oviposition Behavior ◽

Particle Sizes ◽

Breeding Sites ◽

Oryctes Rhinoceros ◽

Rhinoceros Beetle ◽

Oviposition Preferences ◽

Choice Tests ◽

And Behavior ◽

Substrate Particle

The coconut rhinoceros beetle (CRB), Oryctes rhinoceros (L.) (Coleoptera: Scarabaeidae), has become one of the most important coconut and oil palm pests. This species was detected attacking coconut palms on Oʻahu, Hawaiʻi in December 2013, and an eradication program was initiated. One of the major challenges for eradication has been the identification of new breeding sites. Information on the factors influencing oviposition is needed to aid in finding sites likely to host the immature stages of this insect. In this study, a series of choice tests were conducted to assess the oviposition preferences of both laboratory-reared and wild-caught CRB. Mated females, of both lab-reared and wild-caught beetles, were offered for oviposition a choice between sand and two mulch substrates, one with small and one with large particle sizes. Both types of CRB laid eggs preferentially in substrate of small particle size rather than large and none laid eggs in sand. Lab-reared and wild-caught CRB differed in their oviposition behavior and size. These results can be used to aid in the identification of breeding sites for management programs and eradication efforts.

Download Full-text

Field evaluation of host kairomones and pheromones for capture of Conophthorus coniperda (Coleoptera: Scolytidae)

The Canadian Entomologist ◽

10.4039/n06-001 ◽

2006 ◽

Vol 138 (5) ◽

pp. 723-732 ◽

Cited By ~ 2

Author(s):

A.M. Brauner ◽

P. de Groot

Keyword(s):

Field Evaluation ◽

Field Studies ◽

Trap Catch ◽

White Pine ◽

Release Rates ◽

Female Response ◽

Pine Cone ◽

Equivalent Efficacy ◽

Trap Catches ◽

Conophthorus Coniperda

AbstractField studies were conducted to determine the attractiveness of monoterpenes and pheromones to the white pine cone beetle, Conophthorus coniperda (Schwarz), the most destructive cone and seed pest of eastern white pine, Pinus strobus L. (Pinaceae). Limonene was identified as a new attractant that acts synergistically when added to the female-produced sex pheromone, pityol. Trap catches were higher with increasing release rates of S-(–)-limonene. The enantiomers of limonene showed equivalent efficacy on mean trap catch. (–)-β-Pinene was not attractive and may be repellent to both sexes, and (–)-α-pinene was shown to have no effect on female response when added to pityol or pityol + S-(–)-limonene. The pheromones trans-verbenol, trans-pinocarveol, and myrtenol were not attractive to C. coniperda.

Download Full-text

THE IMPORTANCE OF PHEROMONE TRAP DENSITY AND TRAP MAINTENANCE FOR THE DEVELOPMENT OF STANDARDIZED MONITORING PROCEDURES FOR THE CODLING MOTH (LEPIDOPTERA: TORTRICIDAE)

The Canadian Entomologist ◽

10.4039/ent112655-7 ◽

1980 ◽

Vol 112 (7) ◽

pp. 655-663 ◽

Cited By ~ 22

Author(s):

Helmut Riedl

Keyword(s):

Monitoring Program ◽

Codling Moth ◽

Pheromone Trap ◽

Relative Increase ◽

Trap Density ◽

Trapping Efficiency ◽

Trap Catch ◽

Future Performance ◽

Moth Scales ◽

Trap Catches

AbstractPheromone trap density is one factor which influences the magnitude of catch and therefore, should be standardized in a monitoring program. Trap catch increased with the area served by a trap, but reached a plateau when the trap density fell below one trap per 7 ha. From these data a quadratic regression was developed which relates the relative increase in trap catch to trap area. This relationship can be used to compare monitoring data obtained with different trap densities.The number of moths previously caught in a sticky trap can affect its future performance. In the Pherocon® 2 trap catches began to decline after a cumulative total of 20 to 30 moths and in the Pherocon 1CP after 50 to 70 moths. The catch totals causing a drop in trapping efficiency were correlated with the size of the adhesive catch surface. The cause for the loss in trapping efficiency appeared to be physical deterioration of the adhesive due to moth scales, other insect parts, or dust rather than an olfactory repellent factor. Trapping efficiency was restored by thoroughly stirring the soiled adhesive. Standard maintenance procedures should be followed to keep the adhesive quality of the catch surface constant and thereby prevent a reduction in catches. Tests with two pheromone dispensers, the Codlemone® rubber septum and the Conrel® microfibres, indicated that both are effective for at least 6 weeks. Codlemone septa resulted in higher catches during the first week of field use. During subsequent weeks there was no difference in attractiveness between the two pheromone lures.

Download Full-text

Anemotactic strategy and optimum flight conditions for host-plant finding in the cabbage root fly, Delia radicum (L.) (Diptera: Anthomyiidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300011743 ◽

1987 ◽

Vol 77 (2) ◽

pp. 271-277 ◽

Cited By ~ 8

Author(s):

S. F. Nottingham

Keyword(s):

Wind Speed ◽

Host Plant ◽

Linear Model ◽

Wind Direction ◽

Generalized Linear Model ◽

Delia Radicum ◽

Trap Catch ◽

Local Wind ◽

Wind Speeds ◽

Trap Catches

AbstractHourly trap catches of Delia radicum (L.) from opposite sides of host-plant (cabbage) and non-host-plant (carrot) plots in eastern England were analysed with respect to local wind direction, wind speed, temperature and humidity. More females were caught around host- than non-host-plant plots. They predominantly approached host-plant plots by upwind movement, but equal upwind and downwind movement occurred to non-host-plant plots. A generalized linear model revealed that wind speed and humidity influenced the total trap catch of females, with wind speeds below 2 m/s and relative humidities above 65% being most favourable to fly activity, while wind speed was the only variable having a significant effect on the trap catches of flies moving upwind to host-plant plots.

Download Full-text

Light-trap catches of African armyworm moths, Spodoptera exempta (Walker) (Lepidoptera: Noctuidae), in relation to rain and wind

Bulletin of Entomological Research ◽

10.1017/s0007485300008907 ◽

1983 ◽

Vol 73 (2) ◽

pp. 315-319 ◽

Cited By ~ 18

Author(s):

M. R. Tucker

Keyword(s):

East Africa ◽

Light Trap ◽

Spodoptera Exempta ◽

Trap Catch ◽

Early Season ◽

African Armyworm ◽

Light Wind ◽

Trap Catches ◽

Lepidoptera Noctuidae ◽

Very High

AbstractThe association between weather and light-trap catches of Spodoptera exempta (Wlk.) was examined for four traps in East Africa, using whole–night catches and several years' data. Large increases in trap catch were found to be (1) significantly associated with rain at all four traps for the period December–March, but not for later in the season; (2) significantly associated with light wind periods at Muguga for December–May, but not later in the year, and not at Nakuru, due to the very high overall frequency of light winds there; and (3) not significantly associated with windshifts at either Muguga or Nakuru. These results suggest that high densities of flying moths, which may give rise to caterpillar outbreaks early in the year, often occur where the rather infrequent early–season rains fall.

Download Full-text