Publications by authors named "Wee Tek Tay"

The entomopathogenic fungus infects diverse insect host species. We present an annotated draft genome of (Commonwealth Scientific and Industrial Research Organisation [CSIRO] strain M-1000) isolated from a species individual, thereby contributing to future research of as a potential biological control agent.

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Background: Helicoverpa armigera is a highly polyphagous species that causes huge losses to agricultural and horticultural crops worldwide. In the cotton industry, H. armigera, including the Australian subspecies Helicoverpa armigera conferta, is largely managed using genetically modified crops that express insecticidal toxins, such as Cry1Ac.

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Multiple Epiphyas species inhabit southwestern Western Australia, including Light Brown Apple Moth (LBAM) Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), a globally significant, polyphagous pest. This study evaluated the efficacy and specificity of lures designed for 3 Epiphyas species: E. postvittana, Epiphyas pulla (Turner), and the undescribed Epiphyas sp.

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The development of effective pest management strategies for Spodoptera frugiperda is a high priority for crop protection across its invasive ranges. Here, we examined six Beauveria and five Metarhizium fungal isolates against this pest. Two Beauveria isolates (B-0571, B-1311) induced high mortality toward 3rd and 6th instar caterpillars and adults.

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The fall armyworm (FAW) Spodoptera frugiperda is thought to have undergone a rapid 'west-to-east' spread since 2016 when it was first identified in western Africa. Between 2018 and 2020, it was recorded from South Asia (SA), Southeast Asia (SEA), East Asia (EA), and Pacific/Australia (PA). Population genomic analyses enabled the understanding of pathways, population sources, and gene flow in this notorious agricultural pest species.

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The fall armyworm (FAW; Spodoptera frugiperda) is one of the major agricultural pest insects. FAW is native to the Americas, and its invasion was first reported in West Africa in 2016. Then it quickly spread through Africa, Asia, and Oceania, becoming one of the main threats to corn production.

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The fall armyworm (FAW), (Lepidoptera, Noctuidae), is a well-known agricultural pest in its native range, North and South America, and has become a major invasive pest around the globe in the past decade. In this review, we provide an overview to update what is known about in its native geographic ranges. This is followed by discussion of studies from the invaded areas to gain insights into 's ecology, specifically its reproductive biology, host plant use, status of insecticide resistance alleles, and biocontrol methods in native and invasive regions.

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Bean leaf beetle (BLB) () has emerged as an important bean pest in Uganda, leading to devastating crop losses. There is limited information on the population genetic structure of BLB despite its importance. In this study, novel microsatellite DNA markers and the partial mitochondrial cytochrome oxidase subunit I (mt) gene sequences were used to analyze the spatial population genetic structure, genetic differentiation and haplotype diversity of 86 samples from 16 (districts) populations.

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Background: Species within the Bemisia tabaci cryptic species complex can cause significant crop damage. We used high-throughput amplicon sequencing to identify the species composition and resistance allele genotypes in field populations from cotton fields in Australia. For selected populations, the resistance phenotype was determined in bioassays and compared with sequencing data.

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Native to the Americas, the invasive Spodoptera frugiperda (fall armyworm; FAW) was reported in West Africa in 2016, followed by its chronological detection across the Old World and the hypothesis of an eastward Asia expansion. We explored population genomic signatures of American and Old World FAW and identified 12 maternal mitochondrial DNA genome lineages across the invasive range. 870 high-quality nuclear single nucleotide polymorphic DNA markers identified five distinct New World population clusters, broadly reflecting FAW native geographical ranges and the absence of host-plant preferences.

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Fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), is a highly polyphagous invasive plant pest that has expanded its global geographic distribution, including recently into much of Australia. Rapid diagnostic tests are required for identification of FAW to assist subsequent management and control. We developed a new loop-mediated isothermal amplification (LAMP) assay based on the mitochondrial cytochrome c oxidase subunit I (COI) gene for accurate and timely diagnosis of FAW in the field.

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The cotton bollworm Helicoverpa armigera is a cosmopolitan pest and its diverse habitats plausibly contribute to the formation of diverse lineages. Despite the significant threat it poses to economic crops worldwide, its evolutionary history and genetic basis of local adaptation are poorly understood. In this study, we de novo assembled a high-quality chromosome-level reference genome of H.

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Management of agricultural pests requires an understanding of pest species diversity, their interactions with beneficial insects and spatial-temporal patterns of pest abundance. Invasive and agriculturally important insect pests can build up very high populations, especially in cropping landscapes. Traditionally, sampling effort for species identification involves small sample sizes and is labour intensive.

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Field evolved resistance to insecticides is one of the main challenges in pest control. The fall armyworm (FAW) is a lepidopteran pest species causing severe crop losses, especially corn. While native to the Americas, the presence of FAW was confirmed in West Africa in 2016.

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Cassava ( Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly . In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected population dynamics and its parasitoids.

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Article Synopsis
  • The study examines worker reproduction in invasive yellow crazy ants and its impact on colony dynamics and interspecific defense.
  • Researchers observed 233 captive colonies and conducted experiments to find that worker reproduction is more common in queenless colonies and linked to the presence of physogastric workers (workers with enlarged abdomens).
  • Results showed physogastric workers are more likely to produce fertile eggs but are less aggressive and effective in foraging compared to normal workers, indicating a trade-off between reproduction and colony defense.
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The fall armyworm (FAW) (J.E. Smith) (Lepidoptera: Noctuidae) has successfully invaded Africa, where it has significantly impacted maize and sorghum production.

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The fall armyworm (FAW), Spodoptera frugiperda, is a major pest native to the Americas that has recently invaded the Old World. Point mutations in the target-site proteins acetylcholinesterase-1 (ace-1), voltage-gated sodium channel (VGSC) and ryanodine receptor (RyR) have been identified in S. frugiperda as major resistance mechanisms to organophosphate, pyrethroid and diamide insecticides respectively.

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Soybean production in Brazil has been markedly affected by invasions of non-native arthropod species that feed on the crop, severely impacting biodiversity, food security, health, and economic development. Data on soybean production losses and increase in insecticide usage over the last two decades have not been explored in association with past invasion events, and the dynamics underlying the recent blitz of invasive species into Brazil remain largely unclear. We provide a review of arthropod invasions in the Brazilian soybean agroecosystem since 1990, indicating that the introductions of Bemisia tabaci (Gennadius) MEAM1 (Hemiptera: Aleyrodidae), Tetranychus urticae (Koch) (Acari: Tetranychidae), and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) are likely correlated with periods of increase in insecticide usage for soybean production.

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Hybridization between invasive and native species has raised global concern, given the dramatic increase in species range shifts and pest outbreaks due to anthropogenic dispersal. Nevertheless, secondary contact between sister lineages of local and invasive species provides a natural laboratory to understand the factors that determine introgression and the maintenance or loss of species barriers. Here, we characterize the early evolutionary outcomes following secondary contact between invasive Helicoverpa armigera and native H.

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The Old World cotton bollworm Helicoverpa armigera was first detected in Brazil with subsequent reports from Paraguay, Argentina, Bolivia, and Uruguay. This pattern suggests that the H. armigera spread across the South American continent following incursions into northern/central Brazil, however, this hypothesis has not been tested.

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The spread of invasive insect pests is becoming an increasing problem for agriculture globally. We discuss a number of invasive insects, already of major economic significance that have recently expanded their range to become truly global threats. These include the noctuid moths Helicoverpa and Spodoptera, whose caterpillars have long been among the worst pests in their native Old and New World habitats, respectively, and the whitefly Bemisia, a major vector of plant virus diseases.

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Five species of noctuid moths, , , , and are major agricultural pests inhabiting various and often overlapping global distributions. Visual identification of these species requires a great deal of expertise and misidentification can have repercussions for pest management and agricultural biosecurity. Here, we report on the complete mitochondrial genomes of and , , and and assembled from high-throughput sequencing data.

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How invasive species overcome challenges associated with low genetic diversity is unclear. Invasive ant populations with low genetic diversity sometimes produce sterile diploid males, which do not contribute to colony labour or reproductive output. We investigated how inbreeding affects colony founding and potential strategies to overcome its effects in the invasive tropical fire ant, Solenopsis geminata.

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Article Synopsis
  • - The cotton bollworm, Helicoverpa armigera, has developed resistance to various insecticides, particularly pyrethroids, making it a significant global pest following its spread to South America and North America.
  • - A key resistance mechanism involves a chimeric cytochrome P450 gene known as CYP337B3, which has multiple alleles and is prevalent globally, including in South America.
  • - The presence of similar alleles in Brazil and Asia suggests that the resistance could have originated from Asian populations, potentially explaining H. armigera's introduction into the Americas.
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Synopsis of recent research by authors named "Wee Tek Tay"

  • - Wee Tek Tay's recent research primarily focuses on the invasion dynamics and management strategies of agricultural pests, particularly the fall armyworm (Spodoptera frugiperda) and the impact of various pest species in Australian agricultural systems.
  • - His studies have demonstrated the effectiveness of specific fungal isolates for pest control, examined population genetic structures of key pests, and developed rapid diagnostic methods for detecting invasive species.
  • - Tay's work contributes to a better understanding of pest ecology, resistance mechanisms, and potential biocontrol strategies, helping to inform integrated pest management practices in agriculture.