Arthropod Pests Research Articles

Myotropic Activities of Tick Pyrokinin Neuropeptides and Analog in Feeding Tissues of Hard Ticks (Ixodidae).

Neuropeptides regulate many important physiological processes in animals. The G protein-coupled receptors of corresponding small neuropeptide ligands are considered promising targets for controlling arthropod pests. Pyrokinins (PKs) are pleiotropic neuropeptides that, in some insect species, stimulate muscle contraction and modulate pheromone biosynthesis, embryonic diapause, and feeding behavior. However, their function remains unknown in ticks. In this study, we reported the myotropic activity of tick endogenous PKs and a PK agonist analog, PK-PEG8 (MS[PEG8]-YFTPRLa), on feeding tissues of two tick species representing the family Ixodidae lineages, namely, Prostriata (Ixodes scapularis) and Metastriata (Rhipicephalus sanguineus). First, we predicted the sequences of two periviscerokinins (PVK), one with a derived ending RNa and five PKs encoded by the CAPA peptide precursor from R. sanguineus and found the encoded PKs were identical to those of R. microplus identified previously. The pharynx-esophagus of both tick species responded with increased contractions to 10 μM of the endogenous PK as well as to PK-PEG8 but not to the scrambled PK peptide, as expected. A dose-dependent myotropic activity of the PK-PEG8 was found for both tick species, validating the analog activity previously found in the pyrokinin recombinant receptor assay. In agreement with the tissue activity elicited, we quantified the relative transcript abundance of R. sanguineus PK receptor in unfed female ticks and found it was the highest in the feeding tissues extracted from the capitulum and lowest in the reproductive tissue. This is the first report of the activity of pyrokinins in ticks. These findings strongly indicate the potential role of PKs in regulating tick blood feeding and therefore, making the tick PK receptor a potential target for interference.

Light sheet fluorescence microscopy for the investigation of blood-sucking arthropods dyed via artificial membrane feeding

Physical methods to control pest arthropods are increasing in importance, but detailed knowledge of the effects of some of these methods on the target organisms is lacking. The aim of this study was to use light sheet fluorescence microscopy (LSFM) in anatomical studies of blood-sucking arthropods in vivo to assess the suitability of this method to investigate the morphological structures of arthropods and changes in these structures over time, using the human louse Pediculus humanus (Phthiraptera: Pediculidae) as sample organism. Plasma treatment was used as an example of a procedure employed to control arthropods. The lice were prepared using an artificial membrane feeding method involving the ingestion of human blood alone and human blood with an added fluorescent dye in vitro. It was shown that such staining leads to a notable enhancement of the imaging contrast with respect to unstained whole lice and internal organs that can normally not be viewed by transmission microscopy but which become visible by this approach. Some lice were subjected to plasma treatment to inflict damage to the organisms, which were then compared to untreated lice. Using LSFM, a change in morphology due to plasma treatment was observed.These results demonstrate that fluorescence staining coupled with LSFM represents a powerful and straightforward method enabling the investigation of the morphology—including anatomy—of blood-sucking lice and other arthropods.Graphical

Improving Natural Enemy Selection in Biological Control through Greater Attention to Chemical Ecology and Host-Associated Differentiation of Target Arthropod Pests.

Simple SummarySome species of insect herbivores can feed on a wide variety of plant species. Over evolutionary time, insect herbivores can associate preferentially with different host-plant species, which frequently leads to genetic divergence between populations of an herbivore species. This phenomenon, referred to as host-associated differentiation (HAD), not only affects insect herbivores, but can also impact their associated natural enemies, particularly predatory or parasitic insects, which are responsible for biological control in agroecosystems. Although the mechanisms underlying HAD in populations of herbivores and associated natural enemies remain underexplored, we argue that the chemical communication between plants, herbivores, and natural enemies likely plays a major role. Chemical cues emitted by plants and insect herbivores influence natural enemy foraging behavior, and divergent chemical cues can lead to natural enemy HAD, ultimately shaping biological control. In this synthesis paper, we explore how the chemical ecology of HAD could influence classical, conservation, and augmentative biological control, and propose research agendas to further biological control efficacy through natural enemy selection.Host-associated differentiation (HAD) refers to cases in which genetically distinct populations of a species (e.g., herbivores or natural enemies) preferentially reproduce or feed on different host species. In agroecosystems, HAD often results in unique strains or biotypes of pest species, each attacking different species of crops. However, HAD is not restricted to pest populations, and may cascade to the third trophic level, affecting host selection by natural enemies, and ultimately leading to HAD within natural enemy species. Natural enemy HAD may affect the outcomes of biological control efforts, whether classical, conservation, or augmentative. Here, we explore the potential effects of pest and natural enemy HAD on biological control in agroecosystems, with emphases on current knowledge gaps and implications of HAD for selection of biological control agents. Additionally, given the importance of semiochemicals in mediating interactions between trophic levels, we emphasize the role of chemical ecology in interactions between pests and natural enemies, and suggest areas of consideration for biological control. Overall, we aim to jump-start a conversation concerning the relevance of HAD in biological control by reviewing currently available information on natural enemy HAD, identifying challenges to incorporating HAD considerations into biological control efforts, and proposing future research directions on natural enemy selection and HAD.

Functionally characterized arthropod pest and pollinator cytochrome P450s associated with xenobiotic metabolism

Functionally characterized arthropod pest and pollinator cytochrome P450s associated with xenobiotic metabolism

Larvicidal Activity of Methyl Benzoate, a Volatile Organic Compound, Against the Mosquitoes Aedes albopictus and Culex pipiens (Diptera: Culicidae).

Methyl benzoate (MBe) is a volatile organic molecule found in various plants; it is used as an insect semiochemical. MBe also has a biorational insecticidal effect against various agricultural and urban arthropod pests. The present study was the first to assess the larvicidal potential of MBe against fourth-instar larvae of the mosquitoes Aedes albopictus (Skuse) and Culex pipiens (L.). A positive association was observed between MBe concentrations and larval mortality in both the species. The highest mortality recorded was 100% for Ae. albopictus and 56% for Cx. pipiens after 24 h of exposure to 200 ppm MBe. The lethal median concentration (LC50) values of MBe against fourth-instar larvae of Ae. albopictus and Cx. pipiens were 61 ppm and 185 ppm, respectively. These results suggest that MBe has great potential for use as an environmentally friendly larvicidal agent for mosquito control.

The Spatial Distribution of the House Mouse, Mus musculus domesticus, in Multi-Family Dwellings.

Simple SummaryThe management of house mice, Mus musculus domesticus, in low-income high-rise multi-family dwellings (MFDs) is often frustrated by the limited resources available through low-bid contracting. An improved understanding of the small-scale distribution of this important public health pest could allow the pest management industry to better allocate its limited time and resources to better managing infestations. This study utilized data from two research projects that measured house mouse infestation rates from four urban low-income MFDs to determine if a significant correlation between neighboring units exists in their infestation status. Results show that such a correlation exists whereby apartments that share a wall, ceiling or floor with a neighboring apartment that has a current infestation are more likely to have existing house mouse activity. This information can be utilized by the pest management industry to design monitoring strategies, during integrated pest management activities, to better ensure the elimination of house mice in low-income high-rise MFDs.The house mouse, Mus musculus domesticus, creates significant public health risks for residents in low-income multi-family dwellings (MFDs). This study was designed to evaluate the spatial distribution of house mice in MFDs. Four low-income high-rise apartment buildings in three cities in New Jersey were selected for building-wide monitoring on two occasions with approximately one year between the monitoring events. The presence of a house mouse infestation was determined by placing mouse bait stations with three different non-toxic baits for a one-week period in all accessible units as well as common areas. Permutation tests were conducted to evaluate house mouse infestation spatial patterns. All four analyzed buildings exhibited a significant correlation between apartments with house mouse infestations and whether they share a common wall or ceiling/floor at both sampling periods except one building during the second inspection, which contained a high number of isolated apartments. Foraging ranges, speed of locomotion, and dispersal behavior of house mice are relatively larger, faster, and more common, respectively, compared to common urban arthropod pests. This could lead to the conclusion that house mice are as likely to infest non-neighboring apartments as those that share a wall or floor/ceiling. However, these results demonstrate that house mouse infestations tend to occur among apartments that share common walls or ceilings/floors. This spatial distribution pattern can be utilized in rodent management plans to improve the efficiency of house mouse management programs in MFDs.

Effects of soil mitigation on lawn-dwelling invertebrates following residential development

Abstract Residential areas are the most rapidly expanding land use type in the southeastern USA. Residential development impairs soil functions primarily through compaction and the removal or burial of topsoil and natural vegetation, which reduces water infiltration and retention, root penetration, and plant establishment. Plant stress reduces plant-derived ecosystem services and increases vulnerability to pests, often leading to supplemental management inputs in the form of irrigation, fertilizers, pesticides and labor. Soil-dwelling invertebrates, including detritivores and natural enemies of pests, drive valuable ecosystem functions that facilitate plant establishment and reduce maintenance inputs. Although poorly understood, soil disturbance during residential development likely disturbs these communities and reduces the services provided by soil-dwelling invertebrates. Here, we compare the effects of two soil compaction mitigation techniques, tillage with and without compost incorporation, on invertebrate communities and the services they provide over 2 years following residential development. We focus on the relationships between detritivores and detritus decomposition rates, entomopathogenic nematodes and the activity density of a key turfgrass pest and other arthropod herbivores and predators. We found that soil mitigation had no detectable benefit for epigeal arthropods within 1 year after disturbance, but that compost-amended soils supported greater arthropod richness and predator activity density than unmitigated soils in the second year after disturbance. In contrast, we found reduced insect-parasitic nematode activity associated with compost amendment. All taxa increased in abundance with time after development. These results can inform more sustainable residential development and landscape maintenance practices for more biodiverse and functional urban and residential ecosystems.

Comparison of Methods for Isolating Entomopathogenic Fungi from Soil Samples

The goal of the present study is to compare the effectiveness of using insect baits versus artificial selective medium for isolating entomopathogenic fungi (EPF) from soil samples. The soil is a rich habitat for microorganisms, including EPF particularly belonging to the genera Metarhizium and Beauveria, which can regulate arthropod pests. Biological products based on fungi are available in the market mainly for agricultural arthropod pest control. Nevertheless, despite the high endemic biodiversity, only a few strains are used in commercial bioproducts worldwide. In the present study, 524 soil samples were cultured on potato dextrose agar enriched with yeast extract supplemented with chloramphenicol, thiabendazole, and cycloheximide (CTC medium). The growth of fungal colonies was observed for 3 weeks. All Metarhizium and Beauveria EPF were morphologically identified at the genus level. Additionally, some isolates were molecularly identified at the species level. Twenty-four out of these 524 soil samples were also surveyed for EPF occurrence using the insect bait method (Galleria mellonella and Tenebrio molitor). A total of 51 EPF strains were isolated (41 Metarhizium spp. and 10 Beauveria spp.) from the 524 soil samples. All fungal strains were isolated either from croplands or grasslands. Of the 24 samples selected for comparison, 91.7% were positive for EPF using Galleria bait, 62.5% using Tenebrio bait, and 41.7% using CTC. Our results suggested that using insect baits to isolate the EPF from the soil is more efficient than using the CTC medium. The comparison of isolation methods in addition to the identification and conservation of EPF has a positive impact on the knowledge about biodiversity. The improvement of EPF collection supports scientific development and technological innovation.

Analysis of Biodegradation of the Synthetic Pyrethroid Cypermethrin by Beauveria bassiana.

Entomopathogenic fungi like Beauveria bassiana play a crucial role in natural control of arthropod pests which are being used in Integrated Pest Management programs. Assessing the compatibility of biological and chemical counterparts used in IPM programs is essential to achieve successful results in pest management. Behavior of four isolates of B. bassiana (ITCC 913, ARSEF 2860, ARSEF 1166, and ARSEF 3041) was tested in the presence of the pyrethroid insecticide cypermethrin. Spore germination and growth bioassays were conducted to assess the impact of cypermethrin on germination and growth. Though growth was not totally inhibited, there was retardation in the germination of spores and growth of the mycelium. Under this condition, ITCC 913 showed highest tolerance toward cypermethrin. Further analysis of the culture crude extracts by GC-MS revealed degradation of the insecticide by B. bassiana and putative intermediates of the degradation pathway were identified. This study reveals the potential of the entomopathogen B. bassiana in degradation of the pyrethroid insecticide cypermethrin. In conclusion, this potentiality of the studied fungus may help in the IPM strategies and find its role in degradation of such chemical pesticide compounds for utilization as a biodegradation agent further.

Arthropod and Disease Management in Boxwood Production

Abstract Boxwood (Buxus spp.) is the most commonly cultivated woody ornamental shrubs in landscape settings and nursery production. Boxwood is grown for its attractive evergreen foliage and versatility in both formal and informal gardens. Meeting the high demand for boxwood plants worldwide has become challenging in recent years as the boxwood industry has been negatively impacted by a growing number of serious diseases and arthropod pests. Globally, the most common arthropods of concern are boxwood leafminer (Monarthropalpus flavus, Diptera: Cecidomyiidae), boxwood psyllid (Psylla buxi; Hemiptera; Psyllidae), Eurytetranychus buxi (Acari: Tetranychidae) and the invasive moth, Cydalima perspectalis (Lepidoptera: Crambidae). Moreover, major diseases of boxwood include boxwood blight (Calonectria pseudonaviculata, Hypocreales: Nectriaceae), Volutella blight (Pseudonectria buxi, Hypocreales: Nectriaceae), and Phytophthora root and crown rot (Phytophthora spp., Peronosporales: Peronosporaceae). These pests and diseases can lead to significant economic losses to growers and can decimate plants in landscape settings. Here we have reviewed recent research advances focused on the description and management of boxwood arthropod pests and diseases. Boxwood arthropod pests and diseases can be managed by implementing integrated arthropod pest and disease management strategies such as sanitary and cultural practices, genetic resistant cultivars, biological and chemical control methods. This information is provided to aid nursery producers, landscape industry professionals, and other stakeholders in developing integrated arthropod pest and disease management plans for boxwood.

Use of Germicidal UV Light to Suppress Grapevine Diseases and Arthropod Pests

Use of Germicidal UV Light to Suppress Grapevine Diseases and Arthropod Pests

Arthropod and Disease Management in Fraser Fir (Pinales: Pinaceae) Christmas Trees in the Southeastern United States

Abstract Fraser fir, Abies fraseri [Pursh] Poir., is one of the most desired Christmas tree species owing to its fragrance, physical appearance, and durability. This species represents a major component of the Christmas tree industry in the southeastern United States, with production occurring in North Carolina, Tennessee, and Virginia. Fraser fir production is a multi-million dollar annual industry despite growing in a limited elevational and latitudinal range. Pest management for Christmas trees is notoriously difficult owing to the near zero-tolerance of most pests, even those causing aesthetic damage. Christmas trees are produced in monocultural environments which make them highly susceptible to several arthropod and fungal pests. We review the major pests affecting Fraser fir Christmas tree production, including their biology, symptoms, and scouting procedures, and current management strategies. In general, pest management in Christmas tree production systems has not changed significantly in the last several decades, and still relies heavily on pesticide usage. We propose several areas in need of research that could help Fraser fir Christmas tree producers mitigate the impacts of climate change and potential new pest species, as well as suggest changes to current or potentially novel integrated pest management strategies which have a chance to provide economic and ecological benefits for this industry.

Effect of physic nut oil against potato cutworm, Agrotis ipsilon

Field and laboratory evaluation of Jatropha curcas oil on Agrotis ipsilon larvae was carried out in the Soil Arthropod Pests Laboratory as well as on farmer’s field. Experimental findings showed that all the four different concentrations (2.5, 5, 10 & 20%) of J. curcas oil were effective and registered 100 per cent mortality of the larvae after 72 hours of application under laboratory conditions. In case of field study, the lowest tuber infestation of potato (9.88 and 11.06 per cent of based on both number and weight basis respectively) and the highest yield (117.38 q/ha) were recorded in 10 per cent concentration of formulated J. curcas oil treated plots.

Potential Insecticidal Effect of a Wasp (<i>Polistes dominulus</i>) and a Bee (<i>Apis mellifera</i>) Venoms in Controlling <i>Spodoptera littoralis</i>

Cotton leaf worm, Spodoptera littoralis, is considered one of the most common arthropod pests that contribute to crop devastation of cotton. Previously, agricultural pests were controlled through the application of chemical insecticides. However, insecticide-resistant insect populations emergence, as well as increasing concerns about the environmental and human health risks. Venomous animals introduce valuable sources of bioactive compounds which are employed for defence. Some of these toxins have high phyletic specificity, making them appropriate for use in IPM programs. This study aims to test the insecticidal effects of Polistes dominulus and Apis mellifera venoms. Crude venoms were examined for their insecticidal effect against cotton leaf worms by four different application methods including: leaf dipping, integument dropping, spraying, and injection. The data demonstrated a strong response to purified (Polistes dominulus) venom at an initial time than that of honey bee (Apis mellifera) which increases response with increasing the dose and the time interval. A dosage of 0.015 - 0.16 ml of both venoms had notably varied in LD50 values on Spodoptera littoralis that showed higher wasp venom toxicity. Cotton leaf worms showed more susceptibility and mortality to the Polistes sp. venom than that of honey bees.

LABORATORY EVALUATION OF THE EFFECTIVENESS OF THE BIOLOGICAL DRUG ENTOLEK K PLANTECO® ON DIFFERENT SPECIES OF PEST INSECTS OF FODDER CROPS

The article presents the data on the results of laboratory tests of effectiveness of the biological drug Entolek K Planteco® on different species of insect pests of fodder crops. The authors used the following pest species as test-objects - imago of Eurydema ornata(Linnaeus, 1758) (Heteroptera, Pentatomidae), larvae of Tettigonia viridissima(Linnaeus, 1758) (Orthoptera, Tettigoniidae), larvae and adults of Anacanthotermes ahngerianus Jacobson, 1904 (Blattodea, Hodotermitidae), adults of Oxythyrea cinctella (Schaum, 1841) (Coleoptera, Scarabaeidae), caterpillars of Pieris rapae (Linnaeus, 1758) (Lepidoptera, Pieridae). Of the pest arthropods tested, the most resistant to the effects of Entolek K Planteco® were the adults of O. cinctella - the death of insects reached 100% in 15 minutes after treatment. The same resistance was shown by E. ornata. The larvae of T. viridissima showed average resistance - 7 minutes. A. ahngerianus and P. rapae were the most susceptible to the preparation - 99- 100% of insects died 5 minutes after treatment. This difference is largely due to the thickness of the chitinous cover of the insects used as test objects. Based on this, we can say that the Entolek K Planteco® can be used with the greatest effectiveness against insect pests with thin covers or in the younger age of larval stage when they are the least resistant. Also, it may be better used against agricultural pests with thick chitinous covers (beetles, adult bugs, etc.) by increasing the concentration. Based on the results of the studies, Planteco® Entolek K can be used against various pests, which are quite numerous on the crops of fodder crops. Analysis of the obtained results showed that after 7-15 minutes (depending on the pest species), the drug efficiency reaches 99-100%. This efficiency is good enough for a biological preparation and will allow to obtain organic products of fodder crops, and then livestock, containing no toxic residues.

Response of the Leaf Roller, Eublemma olivacea Wlk to Applications of Weeding and Insecticidal Treatments on Eggplant, Solanum melongena L

Different strategies had been used for controlling the pest and stabilizing the productivity of the cropping systems. Weeding and insecticide application are some of the crop management practices that minimize the incidence and damage of insect pests in eggplant crops in order to enhance its growth and yield performance. Eggplant (Solanum melongena L.) is a popular and very important vegetable crop that is infested and damaged by arthropod pests in Nigeria. Field experiments were conducted to evaluate the of weeding frequency and conventional insecticide application in the control of leaf roller (Eublemma olivacea Wlk.) in eggplant. Five application concentrations of magic force (0.0, 0.5, 1.0, 1.5, and 2.0L/ha) and four weeding frequencies were assessed using split- plot laid out in randomized complete block design (RCBD) replicated three times. Results showed that three weedings and the application of insecticide at 1.5l/ha were found to be effective in reducing the population of E. olivacea and eggplant leaves damage. It further showed that these practices improved the number of eggplant fruits, fruit weight and fruit yield during the 2019 and 2020 cropping seasons in the study area combining three weedings with an appropriate insecticide (1.5l/ha) concentration rate is recommended for the control of eggplant leaf roller (E. olivacea) to poor resource farmers in the study area.

Survey of Florida Olive Groves during Olive Fruit Development: Monitoring for Stink Bugs and Olive Fruit Flies

Olives, Olea europaea L. (Oleaceae), are an emerging commercial crop in Florida; however, potential arthropod threats during olive tree establishment and fruit development remain uncharacterized. Two potential pests that may threaten olive fruit production directly are native and invasive pentatomid stink bugs, which are important pest species of many crops in the southeast, and the invasive olive fruit fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae),which is not known to be established in Florida. Monitoring for stink bugs during fruit maturation was done using dual funnel tube traps baited with stink bug lures. Yellow sticky card traps baited with food and pheromone lures were used to monitor for the olive fruit fly. Both trap types were placed in tree canopies in 4 North Central Florida olive groves during the anticipated fruit development period for 2 growing seasons. Whereas neither of the invasive species targeted (Halyomorpha halys Stål [Hemiptera: Pentatomidae] or B. oleae) were detected, several other potential pests were identified including brown stink bugs (Euschistus spp.; Hemiptera: Pentatomidae), glassy winged sharpshooters, Homalodisca vitripennis Germar (Hemiptera: Cicadellidae), and grasshoppers. No fruit damage attributable to arthropod pests was detected although fruit production was very low with limited samples. These results contribute to awareness of potential pests that may jeopardize olive fruit production and aid in the future studies to develop effective monitoring activities for Florida growers.

Role of Lygus hesperus (Hemiptera: Miridae) Adult Feeding on Deformation of Blackberry Fruits

Role of <i>Lygus hesperus</i> (Hemiptera: Miridae) Adult Feeding on Deformation of Blackberry Fruits

Diatomaceous Earth for Arthropod Pest Control: Back to the Future.

Nowadays, we are tackling various issues related to the overuse of synthetic insecticides. Growing concerns about biodiversity, animal and human welfare, and food security are pushing agriculture toward a more sustainable approach, and research is moving in this direction, looking for environmentally friendly alternatives to be adopted in Integrated Pest Management (IPM) protocols. In this regard, inert dusts, especially diatomaceous earths (DEs), hold a significant promise to prevent and control a wide range of arthropod pests. DEs are a type of naturally occurring soft siliceous sedimentary rock, consisting of the fossilized exoskeleton of unicellular algae, which are called diatoms. Mainly adopted for the control of stored product pests, DEs have found also their use against some household insects living in a dry environment, such as bed bugs, or insects of agricultural interest. In this article, we reported a comprehensive review of the use of DEs against different arthropod pest taxa, such as Acarina, Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Ixodida, Lepidoptera, when applied either alone or in combination with other techniques. The mechanisms of action of DEs, their real-world applications, and challenges related to their adoption in IPM programs are critically reported.

Dimethoate insecticide application seldom reduces silvertop incidence in grass seed fields on the Canadian prairies

Many arthropods have been reported (but none confirmed) as causal agents of sterile seed heads in perennial grass seed fields, known as silvertop or white head. Field studies to identify the arthropods that cause silvertop were conducted in five perennial grass species at seven sites in Saskatchewan, Canada, over several years. The effect timing of insecticide application in spring — early, mid, or late — and of post-harvest residue management — mowing, close mowing with straw removed (scalping), and burning — on subsequent arthropod populations, silvertop incidence, and seed yield were assessed. Samples of grass tillers and sweep net collections were taken regularly, and the arthropods collected were identified to family level and counted. Arthropod populations from sweep samples varied among sites and dates in number and taxon composition, but no arthropod assemblage was consistently associated with silvertop in any grass species. Thrips were the most numerous arthropods on tillers at all sites. Insecticide application often temporarily reduced arthropod populations, but reduced silvertop incidence at only 1 of 15 site-years, and increased seed yield at only 1 of 17 site-years. Scalping or burning did not reduce silvertop incidence but often increased healthy seed head numbers and seed yield relative to mowing, the standard treatment. The majority of Kentucky bluegrass fields had extremely low seed yields unrelated to silvertop or arthropod levels. This extensive study, across a range of grass species and management regimes, provides strong support for the conclusion based on previous work that arthropod pests are not the sole cause of silvertop.