Capsid Proteins are Necessary for Replication of a Parvovirus

Despite tight genetic compression, viral genomes are often organized in functional gene clusters, a modular structure that might favor their evolvability. This has greatly facilitated biotechnological developments, such as the recombinant Adeno-Associated Virus (AAV) systems for gene therapy. Following this lead, we endeavored to engineer the related insect parvovirus Junonia coenia densovirus (JcDV) to create addressable vectors for insect pest biocontrol. To enable safer manipulation of capsid mutants, we translocated the non-structural ( ns ) gene cluster outside the viral genome. To our dismay, this yielded a virtually non-replicable clone. We linked the replication defect to an unexpected modularity breach, as ns translocation truncated the overlapping 3’ UTR of the capsid transcript ( vp ). We found that native vp 3’UTR is necessary to high VP production, but that decreased expression do not adversely impact the expression of NS proteins, which are known replication effectors. As nonsense vp mutations recapitulate the replication defect, VP proteins appear directly implicated in the replication process. Our findings suggest intricate replication-encapsidation couplings that favor maintenance of genetic integrity. We discuss possible connections with an intriguing cis-packaging phenomenon previously observed in parvoviruses, whereby capsids preferentially package the genome from which they were expressed. IMPORTANCE Densoviruses could be used as biological control agents to manage insect pests. Such applications require in depth biological understanding and associated molecular tools. However, the genomes of these viruses remain hard to manipulate due too poorly tractable secondary structures at their extremities. We devised a construction strategy that enable precise and efficient molecular modifications. Using this approach, we endeavored to create a split clone of the Junonia coenia densovirus (JcDV) that can be used to safely study the impact of capsid mutations on host specificity. Our original construct proved to be non-functional. Fixing this defect led us to uncover that capsid proteins and their correct expression are essential for continued rolling-hairpin replication. This points to an intriguing link between replication and packaging, which might be shared with related viruses. This serendipitous discovery illustrates the power of synthetic biology approaches to advance our knowledge of biological systems.

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Capsid Proteins are Necessary for Replication of a Densovirus

10.1101/2020.04.06.028852 ◽

2020 ◽

Author(s):

Deborah Garcia ◽

Doriane Mutuel ◽

Mylène Ogliastro ◽

Guillaume Cambray

Keyword(s):

Insect Pests ◽

Insect Pest ◽

Gene Clusters ◽

Capsid Proteins ◽

Junonia Coenia ◽

Replication Process ◽

Adeno Associated Virus ◽

Viral Genomes ◽

Construction Strategy ◽

The Impact

AbstractDespite tight genetic compression, viral genomes are often organized in functional gene clusters, a modular structure that might favor their evolvability. This has greatly facilitated biotechnological developments, such as the recombinant Adeno-Associated Virus (AAV) systems for gene therapy. Following this lead, we endeavored to engineer the related insect parvovirus Junonia coenia densovirus (JcDV) to create addressable vectors for insect pest biocontrol. To enable safer manipulation of capsid mutants, we translocated the non-structural (ns) gene cluster outside the viral genome. To our dismay, this yielded a virtually non-replicable clone. We linked the replication defect to an unexpected modularity breach, as ns translocation truncated the overlapping 3’ UTR of the capsid transcript (vp). We found that native vp 3’UTR is necessary to high VP production, but that decreased expression do not adversely impact the expression of NS proteins, which are known replication effectors. As nonsense vp mutations recapitulate the replication defect, VP proteins appear directly implicated in the replication process. Our findings suggest intricate replication-encapsidation couplings that favor maintenance of genetic integrity. We discuss possible connections with an intriguing cis-packaging phenomenon previously observed in parvoviruses, whereby capsids preferentially package the genome from which they were expressed.ImportanceDensoviruses could be used as biological control agents to manage insect pests. Such applications require in depth biological understanding and associated molecular tools. However, the genomes of these viruses remain hard to manipulate due too poorly tractable secondary structures at their extremities. We devised a construction strategy that enable precise and efficient molecular modifications. Using this approach, we endeavored to create a split clone of the Junonia coenia densovirus (JcDV) that can be used to safely study the impact of capsid mutations on host specificity. Our original construct proved to be non-functional. Fixing this defect led us to uncover that capsid proteins and their correct expression are essential for viral replication. This points to an intriguing link between replication and packaging, which might be shared we related viruses. This serendipitous discovery illustrates the power of synthetic biology approaches to advance our knowledge of biological systems.

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THE IMPACT OF TRANSGENIC BRINJAL FOR THE CONTROL OF LEUCINODES ORBONALIS GUENEE AND POSSIBLE EFFECTS ON NON-TARGET ARTHROPODS: A COMPREHENSIVE REVIEW

Plant Protection ◽

10.33804/pp.004.03.3420 ◽

2020 ◽

Vol 4 (3) ◽

pp. 131-135

Author(s):

Wali Muhammad ◽

Khadija Javed ◽

Humayun Javed ◽

Munir Ahmad ◽

Muhammad Azam Khan

Keyword(s):

Insect Pests ◽

Abiotic Factors ◽

Insect Pest ◽

Solanum Melongena ◽

Asia Pacific ◽

Factors Affecting ◽

Leucinodes Orbonalis ◽

Future Challenges ◽

Fruit Borer ◽

The Impact

Brinjal (Solanum melongena L.) is the most important vegetable crop in the Asia Pacific region, with Pakistan being the seventh largest producer. There are many biotic and abiotic factors affecting its production in terms of quantity and quality including insect pests as a significant constraint. In Pakistan, the brinjal shoot and fruit borer, Leucinodes orbonalis is the major insect pest of brinjal. However, some other chewing and sap-sucking insects are also essential pests. Bt-brinjal, a transgenic variety, has been introduced in India and Bangladesh for the management of lepidopteran pests. Before the commercialization of transgenic brinjal in Pakistan, it must be assessed for its effects on the environment and non-target organisms. This study is presenting the overview of transgenic brinjal as an option to manage brinjal shoot and fruit borer along with current and future challenges in areas of its commercialization.

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Observations and insights on pasture persistence in New Zealand

NZGA: Research and Practice Series ◽

10.33584/rps.15.2011.3219 ◽

2011 ◽

Vol 15 ◽

pp. 47-51

Author(s):

P.M.S. Lane

Keyword(s):

New Zealand ◽

Soil Fertility ◽

Insect Pests ◽

Insect Pest ◽

Stress Factors ◽

The Past ◽

Clover Root ◽

The Impact

This essay contains personal observations and interpretations by the author on the persistence of pastures in the northern North Island. Key pasture stress factors are identified as the increase of farming intensity over the past two decades, the impact of pasture renewal techniques and the role of pasture species on insect pest (particularly black beetle and clover root weevil) interactions. Keywords: insect pests, soil fertility, pasture renewal, cultivars, endophyte

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Surfactantless Emulsions Containing Eugenol for Imidacloprid Solubilization: Physicochemical Characterization and Toxicity against Insecticide-Resistant Cimex lectularius

Molecules ◽

10.3390/molecules25102290 ◽

2020 ◽

Vol 25 (10) ◽

pp. 2290 ◽

Cited By ~ 2

Author(s):

Mariano Cáceres ◽

Eduardo Guzmán ◽

Agustín Alvarez-Costa ◽

Francisco Ortega ◽

Ramón G. Rubio ◽

...

Keyword(s):

Pest Control ◽

Insect Pests ◽

Insect Pest ◽

Physicochemical Characterization ◽

Water Soluble ◽

Cimex Lectularius ◽

Bed Bugs ◽

Bed Bug ◽

Development Of Resistance ◽

The Impact

Synthetic insecticides have been used for a long time as one of the most effective tools for insect pest control. However, the re-emergence of insect pests and their fast development of resistance, as has occurred for pyrethroid-resistant bed bugs Cimex lectularius L., make it necessary to develop new and safe strategies for effective pest control. This has fostered the research on new eco-sustainable formulations based on essential oils, which allows reducing the impact associated with the intensive use of synthetic insecticides on the environment and their effects on human health. This research explores the stability of water/eugenol/ethanol surfactantless emulsions loaded with imidacloprid (0.003 wt%), and their toxicity against a resistant bed bug strain. The results have shown that these emulsions enable the solubilization of a poorly water-soluble drug, such as the imidacloprid, without any significant modification of their stability. Furthermore, the application of the obtained formulations against the pyrethroid-resistant bed bug results in mortality in the 50–85% range upon topical and spray applications, with the increase of the eugenol content enhancing the effectiveness of the formulations. It may be expected that the ternary water/eugenol/ethanol mixtures could be further developed in the preparation of ready to use formulations, enabling the dispersion of insecticides for pest control.

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Management of beneficial invertebrates and their potential role in integrated pest management for Australian grain systems

Australian Journal of Experimental Agriculture ◽

10.1071/ea07424 ◽

2008 ◽

Vol 48 (12) ◽

pp. 1531 ◽

Cited By ~ 6

Author(s):

Joanne C. Holloway ◽

Michael J. Furlong ◽

Philip I. Bowden

Keyword(s):

Integrated Pest Management ◽

Pest Management ◽

Natural Enemies ◽

Insect Pests ◽

Cropping Systems ◽

Insect Pest ◽

Environmental Benefits ◽

Pest Species ◽

Grain Crops ◽

The Impact

Beneficial invertebrates (predators and parasitoids) can make significant contributions to the suppression of insect pest populations in many cropping systems. In Australia, natural enemies are incorporated into integrated pest management programs in cotton and horticultural agroecosystems. They are also often key components of effective programs for the management of insect pests of grain crops in other parts of the world. However, few studies have examined the contribution of endemic natural enemies to insect pest suppression in the diverse grain agroecosystems of Australia. The potential of these organisms is assessed by reviewing the role that natural enemies play in the suppression of the major pests of Australian grain crops when they occur in overseas grain systems or other local agroecosystems. The principal methods by which the efficacy of biological control agents may be enhanced are examined and possible methods to determine the impact of natural enemies on key insect pest species are described. The financial and environmental benefits of practices that encourage the establishment and improve the efficacy of natural enemies are considered and the constraints to adoption of these practices by the Australian grains industry are discussed.

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Nanopesticides: A Systematic Review of Their Prospects With Special Reference to Tea Pest Management

Frontiers in Nutrition ◽

10.3389/fnut.2021.686131 ◽

2021 ◽

Vol 8 ◽

Author(s):

Bhabesh Deka ◽

Azariah Babu ◽

Chittaranjan Baruah ◽

Manash Barthakur

Keyword(s):

Pest Management ◽

Insect Pests ◽

Plant Protection ◽

Insect Pest ◽

Management Strategies ◽

Crop Protection ◽

Tea Plant ◽

Research Field ◽

Active Ingredients ◽

The Impact

Background: Tea is a natural beverage made from the tender leaves of the tea plant (Camellia sinensis Kuntze). Being of a perennial and monoculture nature in terms of its cultivation system, it provides a stable micro-climate for various insect pests, which cause substantial loss of crop. With the escalating cost of insect pest management and increasing concern about the adverse effects of the pesticide residues in manufactured tea, there is an urgent need to explore other avenues for pest management strategies.Aim: Integrated pest management (IPM) in tea invites an multidisciplinary approach owing to the high pest diversity in the perennial tea plantation system. In this review, we have highlighted current developments of nanotechnology for crop protection and the prospects of nanoparticles (NPs) in plant protection, emphasizing the control of different major pests of tea plantations.Methods: A literature search was performed using the ScienceDirect, Web of Science, Pubmed, and Google Scholar search engines with the following terms: nanotechnology, nanopesticides, tea, and insect pest. An article search concentrated on developments after 1988.Results: We have described the impact of various pests in tea production and innovative approaches on the use of various biosynthesized and syntheric nanopesticides against specific insect pest targets. Simultaneously, we have provided support for NP-based technology and their different categories that are currently employed for the management of pests in different agro-ecosystems. Besides the broad categories of active ingredients (AI) of synthetic insecticides, pheromones and natural resource-based molecules have pesticidal activity and can also be used with NPs as a carriers as alternatives to traditional pest control agents. Finally, the merits and demerits of incorporating NP-based nanopesticides are also illustrated.Conclusions: Nanopesticides for plant protection is an emerging research field, and it offers new methods to design active ingredients amid nanoscale dimensions. Nanopesticide-based formulations have a potential and bright future for the development of more effective and safer pesticide/biopesticides.

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The impact of bioinsecticide overdoses of Beauveria bassiana on species diversity and abundance of not targeted arthropods in South Sumatra (Indonesia) freshwater swamp paddy

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210541 ◽

2020 ◽

Vol 21 (5) ◽

Author(s):

KHOIRUL IKHSANUDIN HANIF ◽

Siti Herlinda ◽

CHANDRA IRSAN ◽

YULIA PUJIASTUTI ◽

GHANNI PRABAWATI ◽

...

Keyword(s):

Species Diversity ◽

Beauveria Bassiana ◽

Insect Pests ◽

Insect Pest ◽

Target Species ◽

Species Dominance ◽

Freshwater Swamp ◽

Abundance And Diversity ◽

The Impact ◽

Predatory Arthropods

Abstract. Hanif KI, Herlinda S, Irsan C, Pujiastuti Y, Prabawati G, Hasbi, Karenina T. 2020. The impact of bioinsecticide overdoses of Beauveria bassiana on species diversity and abundance of not targeted arthropods in South Sumatra (Indonesia) freshwater swamp paddy. Biodiversitas 21: 2124-2136. Bioinsecticides have been shown to reduce insect pest populations, but it is necessary to monitor the effect of bioinsecticide overdoses on non-target arthropods because they are abundant in rice fields. This study aimed to analyze the impact of bioinsecticide overdoses of B. bassiana on species diversity and abundance of non-target arthropods. Bioinsecticides derived from Beauveria bassiana were sprayed on the paddy every two weeks until the ripening stage, at a dose of 1, 2, 3, 4 L.ha-1, control (without insecticide), and abamectin as prescribed. The abundance of spiders and predatory arthropods did not decrease when bioinsecticides were applied but the abundance of spiders, especially Lycosidae and Salticidae dropped significantly when abamectin was applied. The abundance of the parasitoid decreased significantly when abamectin was applied, but the abundance of parasitoids applied by bioinsecticide was not significantly different from those of control. The abundance of insect pests started to decrease when bioinsecticide was applied to 2, 3 or 4 L.ha-1. The diversity species of non-target arthropods (spiders, predatory arthropods, and parasitoids) tended to decrease when it was applied bioinsecticides 3 and 4 L.ha-1 or abamectin, but their abundance remained high and no species dominance was found. For this reason, the correct dosage for suppressing insect pests abundance by not decreasing the abundance and diversity of non-target species is 2 L.ha-1 and applied when herbivore abundance is high.

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Instant Insights: Climate change, insect pests and invasive species

10.19103/9781786769282 ◽

2020 ◽

Keyword(s):

Climate Change ◽

Invasive Species ◽

Pest Management ◽

Insect Pests ◽

Insect Pest ◽

Management Strategies ◽

Cereal Aphids ◽

Plant Interactions ◽

Impact Of Climate Change ◽

The Impact

This specially curated collection features three reviews of current and key research on climate change, insect pests and invasive species. The first chapter reviews the impact of climate change on insect pests and how it has affected insect pest development and population dynamics, activity and abundance, diversity and geographical distribution. It also assesses insect-host plant interactions and the effectiveness of crop pest management techniques. The second chapter discusses the literature on the potential impact of climate change on the principal insect pests of wheat, including cereal aphids, Hessian fly, orange wheat blossom midge, cereal leaf beetle and cotton bollworm. It assesses the different methods used to assess likely impacts as well climate change effects on biological control in wheat systems. The final chapter surveys what we know about the ecology of invasive species and potential management strategies. In particular, it assesses how integrated pest management (IPM) needs to evolve to deal with invasive species, particularly in focussing more on monitoring, prevention and rapid response.

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Insect Pest Management in Stored Products

Outlooks on Pest Management ◽

10.1564/v31_feb_05 ◽

2020 ◽

Vol 31 (1) ◽

pp. 24-35 ◽

Cited By ~ 2

Author(s):

Somiahnadar Rajendran

Keyword(s):

Pest Management ◽

Insect Pests ◽

Insect Pest ◽

Control Measures ◽

Stored Products ◽

Insect Pest Management ◽

Insect Infestation ◽

Combination Treatments ◽

Agricultural Produce ◽

Food Commodities

Insects are a common problem in stored produce. The author describes the extent of the problem and approaches to countering it. Stored products of agricultural and animal origin, whether edible or non-edible, are favourite food for insect pests. Durable agricultural produce comprising dry raw and processed commodities and perishables (fresh produce) are vulnerable to insect pests at various stages from production till end-use. Similarly, different animal products and museum objects are infested mainly by dermestids. Insect pests proliferate due to favourable storage conditions, temperature and humidity and availability of food in abundance. In addition to their presence in food commodities, insects occur in storages (warehouses, silos) and processing facilities (flour mills, feed mills). Insect infestation is also a serious issue in processed products and packed commodities. The extent of loss in stored products due to insects varies between countries depending on favourable climatic conditions, and pest control measures adopted. In stored food commodities, insect infestation causes loss in quantity, changes in nutritional quality, altered chemical composition, off-odours, changes in end-use products, dissemination of toxigenic microorganisms and associated health implications. The insects contribute to contaminants such as silk threads, body fragments, hastisetae, excreta and chemical secretions. Insect activity in stored products increases the moisture content favouring the growth of moulds that produce mycotoxins (e.g., aflatoxin in stored peanuts). Hide beetle, Dermestes maculatus infesting silkworm cocoons has been reported to act as a carrier of microsporidian parasite Nosema bombycis that causes pebrine disease in silkworms. In dried fish, insect infestation leads to higher bacterial count and uric acid levels. Insects cause damage in hides and skins affecting their subsequent use for making leather products. The trend in stored product insect pest management is skewing in favour of pest prevention, monitoring, housekeeping and finally control. Hermetic storage system can be supplemented with CO2 or phosphine application to achieve quicker results. Pest detection and monitoring has gained significance as an important tool in insect pest management. Pheromone traps originally intended for detection of infestations have been advanced as a mating disruption device ensuing pest suppression in storage premises and processing facilities; pheromones also have to undergo registration protocols similar to conventional insecticides in some countries. Control measures involve reduced chemical pesticide use and more non-chemical inputs such as heat, cold/freezing and desiccants. Furthermore, there is an expanding organic market where physical and biological agents play a key role. The management options for insect control depend on the necessity or severity of pest incidence. Generally, nonchemical treatments, except heat, require more treatment time or investment in expensive equipment or fail to achieve 100% insect mortality. Despite insect resistance, environmental issues and residue problems, chemical control is inevitable and continues to be the most effective and rapid control method. There are limited options with respect to alternative fumigants and the alternatives have constraints as regards environmental and health concerns, cost, and other logistics. For fumigation of fresh agricultural produce, new formulations of ethyl formate and phosphine are commercially applied replacing methyl bromide. Resistance management is now another component of stored product pest management. In recent times, fumigation techniques have improved taking into consideration possible insect resistance. Insect control deploying nanoparticles, alone or as carriers for other control agents, is an emerging area with promising results. As there is no single compound with all the desired qualities, a necessity has arisen to adopt multiple approaches. Cocktail applications or combination treatments (IGRs plus organophosphorus insecticides, diatomaceous earth plus contact insecticides, nanoparticles plus insecticides/pathogens/phytocompounds and conventional fumigants plus CO2; vacuum plus fumigant) have been proved to be more effective. The future of store product insect pest management is deployment of multiple approaches and/or combination treatments to achieve the goal quickly and effectively.

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Mild Abiotic Stress Affects Development and Stimulates Hormesis of Hemp Aphid Phorodon cannabis

Insects ◽

10.3390/insects12050420 ◽

2021 ◽

Vol 12 (5) ◽

pp. 420

Author(s):

Roma Durak ◽

Malgorzata Jedryczka ◽

Beata Czajka ◽

Jan Dampc ◽

Katarzyna Wielgusz ◽

...

Keyword(s):

Glutathione Transferase ◽

Insect Pest ◽

Mild Stress ◽

Population Parameters ◽

Live Feed ◽

Average Fecundity ◽

The Impact ◽

Considerable Damage ◽

Group 1 ◽

Future Management

The hemp aphid Phorodon cannabis Passerini is a well- known (Asia, Europe) or newly emerging (North America) insect. It is a monophagous insect pest causing considerable damage in field and glasshouse cultivations. The aim of this work was to study the effects of meteorological (temperature) and agronomical (herbicide) factors on the biology of the hemp aphid. In one experiment, hemp plants were kept at constant temperatures ranging from 20 to 30 °C, and aphid survival and fecundity were measured. In a related experiment conducted at 20 °C, plants were treated with field-appropriate rates of a selective graminicide containing quizalofop-P-tefuryl (40 gL−1, 4.38%, HRAC group 1), commonly used to control weeds in hemp, and aphid enzyme activity was measured in addition to population parameters. We found that hemp aphids could live, feed and reproduce within the whole studied range of temperatures, demonstrating its great evolutionary plasticity. However, the optimal temperature for development was 25 °C, at which the insect lived and reproduced for 25 and 15 days, respectively, with an average fecundity of 7.5 nymphs per reproduction day. The herbicide treatment increased the activity of superoxide dismutase (SOD), catalase (CAT), β-glucosidase, S-glutathione transferase (GST), oxidoreductive peroxidase (POD), and polyphenol oxidase (PPO) in the aphids, but only on certain days after treatment, which indicates a mild stress in aphid tissues, related to a higher reproduction and changed feeding behavior; aphids moved from the actively growing tips compared to untreated plants. The results of these experiments are discussed in terms of the impact on the future management of this pest.

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