Phylogenetic clustering of wingbeat frequency and flight-associated morphometrics across insect orders

Wingbeat frequency in insects is an important variable in aerodynamic and energetic analyses of insect flight and often is studied on a family‐ or species‐level basis. Meta‐analyses of these studies report order‐level patterns suggesting that flight strategy is moderately well conserved phylogenetically. Studies incorporated into these meta‐analyses, however, use variable methodologies across different temperatures, which may confound results and phylogenetic patterns. In the present study, a high‐speed camera is used to measure wingbeat frequency in a wide variety of species (n = 102) under controlled conditions aiming (i) to determine the validity of previous meta‐analyses showing phylogenetic clustering of flight strategy and (ii) to identify new evolutionary patterns between wingbeat frequency, body mass, wing area, wing length and wing loading at the order level. All flight‐associated morphometrics significantly affect wingbeat frequency. Linear models show that wing area explains the most amount of variation in wingbeat frequency (r2 = 0.59, P ≤ 0.001), whereas body mass explains the least (r2 = 0.09, P ≤ 0.01). A multiple regression model incorporating both body mass and wing area is the best overall predictor of wingbeat frequency (r2 = 0.84, P ≤ 0.001). Order‐level phylogenetic patterns across relationships are consistent with previous studies. Thus, the present study provides experimental validation of previous meta‐analyses and provides new insights into phylogenetically conserved flight strategies across insect orders

Botanical biopesticides – where to now?

Like Apollo 13 in the eponymously named 1995 film, crop protection has a problem, well actually, more than one problem. Unlike the Apollo disaster there is however, no quick fix on the horizon. The first, and for growers often the more serious problem, is that populations of insects and other pests, are developing resistance to pesticides; indeed there are almost 600 species of arthropod for which resistance to the most commonly used crop protection products has been reported. The situation with weeds and plant pathogens is equally parlous, with cases of resistance to herbicides and fungicides growing at an alarming rate worldwide. The second problem, and one that potentially poses a danger to us all is the realization that the use of some conventional synthetic pesticides, widely perceived by the public and some scientists, as a danger to beneficial insects such as pollinators, may also be a threat to insects in general. The pressure put on growers by the public condemnation of the use and the reducing commercial availability of effective conventional synthetic pesticides means that the development of viable alternatives is of increasing importance. The obvious, and the option favoured by the European Union, is to increase the wholehearted uptake of Integrated Pest Management (IPM) by growers of all kinds. Given that successful IPM programmes and those likely to do not preclude the use of pesticides it would be foolish, in most cropping situations at least, to advocate reliance on biological control options on their own. Where approaches to prevent pest problems, such as through the use of host-plant resistance and crop rotations, have been unsuccessful, this effectively leaves us with the biopesticides to combat pest outbreaks. Biopesticides are typically either derived from plants (the botanicals) or from microbial agents such as entomopathogenic fungi. We desperately need further work in this area, without increased funding and just as importantly, changes in the regulatory framework and the attitudes of growers, improvements in developing sustainable and environmentally friendly crop production will be a long time coming

PCR-based gut content analysis to identify arthropod predators of Haplodiplosis marginata

Saddle gall midge (Haplodiplosis marginata) is a cereal pest exhibiting sporadic outbreaks for which chemical control options are limited. Integrated Pest Management programs may offer a means of suppressing H. marginata outbreaks, reducing pesticide input. Many IPM programs benefit from the natural population suppression inflicted through predation and parasitism. The larval stage of H. marginata overwinters in the soil and may be preyed upon by ground-dwelling arthropods, however the natural enemies of H. marginata remain unrecognized. A PCR-based assay for detecting H. marginata in the guts of predators was designed using novel species-specific primers. Feeding trials involving H. marginata larvae showed a detectability half-life of 31.07 h post-feeding in Nebria brevicollis. The guts of field-caught Carabidae were screened for H. marginata DNA. Four species: Poecilus versicolor, Nebria brevicollis, Harpalus rufipes and Loricera pilicornis were identified as natural enemies of H. marginata for the first time. A higher proportion of positive results were obtained at the end of H. marginata emergence (July) compared to the beginning (May). The importance of understanding trophic interactions in the management of H. marginata is discussed in addition to the potential uses for the newly designed assay and primers

Terpene based biopesticides as potential alternatives to synthetic insecticides for control of aphid pests on protected ornamentals

Biopesticides based on plant extracts offer a promising alternative to the use of conventional synthetic pesticides. However, biopesticide products must provide acceptable levels of control. To date, few studies have investigated the efficacy of biopesticide products under conditions that reflect commercial practice. Here we report results from three experiments, one completed under glasshouse conditions in 2014 and two completed under polytunnel conditions, in 2015 and 2016, respectively. These experiments tested the efficacy of three terpene based biopesticides used to control two aphid species, peach-potato aphid (Myzus persicae) and melon and cotton aphid (Aphis gossypii), on ornamental crops. The three biopesticide products tested were orange oil (60 g active ingredient per litre, formulated as a soluble liquid), the essential oil from Chenopodium ambrosioides variety nr. ambrosioides (16.75% active ingredient, formulated as an oil dispersion) and neem oil (1% active ingredient, formulated as emulsifiable concentrate). The biopesticides tested were applied as foliar sprays using a water volume of 600 l/Ha and all experiments were done at Harper Adams University, Shropshire, UK. The biopesticide products tested gave statistically similar levels of control of M. persicae populations on pansy plants as the conventional synthetic insecticide flonicamid (500 g/kg active ingredient, formulated as a wettable granule) and spirotetramat (150 g/l active ingredient, formulated as an oil dispersion). All products reduced numbers of aphids by at least 85% during the experimental period. Orange oil also gave a similar speed of kill to flonicamid and was faster acting than spirotetramat, two conventional synthetic insecticides that are widely used to control aphid pests of ornamental crops. Against A. gossypii on Hebe, orange oil gave similar levels of control (90% reduction in aphid numbers) as flonicamid (98% reduction in aphid numbers), when applied with a spray interval of three days (as per label recommendation). The essential oil from Chenopodium ambrosioides variety nr. ambrosioides was not as effective as flonicamid but did significantly reduced (80% reduction in aphid numbers) numbers of A. gossypii on Hebe compared to a water control when applied with a spray interval of five days. Neem oil was not effective against A. gossypii. Importantly, there was little evidence of any phytotoxicity caused by any of the biopesticide products tested. The potential to use these products as part of an Insecticide Resistance Management (IRM) programme are discussed

A review of the biology, ecology and control of saddle gall midge,Haplodiplosis marginata(Diptera: Cecidomyiidae) with a focus on phenological forecasting

Saddle gall midge Haplodiplosis marginata (Diptera: Cecidomyiidae) is a pest of cereals across Europe. The occasional nature of this pest has resulted in limited and sporadic research activity. There remain important gaps in knowledge due either to a genuine lack of research or to previous research being difficult to access. These knowledge gaps make the development of effective control options difficult. Here, we review the existing literature in an attempt to consolidate the information on H. marginata from research which spans several decades and encompasses many different countries. The current distribution and pest status of this insect are updated, along with the methods of cultural and chemical control available to growers. The biology and life history of the insect are described in detail and the ecological processes governing them are discussed. A forecasting model is presented which allows the emergence of this pest in the UK to be predicted from degree day data, and the potential application of this model in management decisions is discussed. Finally, the areas in most need of further research are identified, along with suggestions of how this information can be used to help develop effective and sustainable management solutions for this pest

Assessing the potential of biopesticides to control the cabbage stem flea beetle Psylliodes chrysocephala

BACKGROUND Cabbage stem flea beetle (CSFB) is an economically important pest of oilseed rape crops in Europe that was effectively controlled by neonicotinoid insecticide seed treatments until they were banned by the European Union in 2013. Since then, CSFB has been a difficult pest to control effectively, in part due to many populations having developed resistance to pyrethroids, the only authorized insecticides used to control this pest in many countries. Alternative solutions are therefore necessary, such as biopesticides. We tested an entomopathogenic fungus, three entomopathogenic bacteria isolates, two fatty acids and azadirachtin against CSFB adults under laboratory conditions. We also tested the efficacy of the pyrethroid insecticide lambda-cyhalothrin. RESULTS Fatty acids were effective, with up to 100% CSFB mortality after 24 h. The entomopathogenic fungus Beauveria bassiana resulted in up to 56% mortality 14 days after treatment. Entomopathogenic bacteria formulations and azadirachtin were not effective (<50% and <40% mortality, respectively). Results from a bioassay using lambda-cyhalothrin indicated that the CSFB used in this study were resistant to this insecticide. CONCLUSION Entomopathogenic fungi and fatty acids could potentially be used to control CSFB as part of an integrated pest management programme. This study is the first to investigate the efficacy of different biopesticides to control CSFB under laboratory conditions. As such, these biopesticides require further testing to optimise the formulation and application methods, and to assess the impact on nontarget organisms. Finally, efficacy under field conditions must be determined to understand the influence of environmental variables

Potential of Entomopathogenic Nematodes to Control the Cabbage Stem Flea Beetle Psylliodes chrysocephala

Cabbage stem flea beetle (CSFB) is an important pest of oilseed rape that was controlled by neonicotinoid seed treatments until they were banned for this use in 2013. Since then, CSFB has been a difficult pest to control, partly due to widespread resistance to pyrethroid insecticides. Alternate solutions are necessary. Here, four entomopathogenic nematode (EPN) species were tested against CSFB adults under laboratory conditions. In addition, a bioassay was completed to test for EPN compatibility with a range of adjuvants (glycerin, xanthan gum and flame retardant) to protect EPNs from UV radiation and desiccation. Results show that EPNs have the potential to control CSFB adults under laboratory conditions. Heterorhabditis bacteriophora caused 75% CSFB mortality at a concentration of 4000 nematodes/mL after six days, Steinernema feltiae caused 80% CSFB mortality when applied at a concentration of 40,000 nematodes/mL after two days, Steinernema carpocapsae caused 85% mortality at a concentration of 10,000 nematodes/mL after six days, and Steinernema kraussei caused no more than 70% CSFB mortality overall compared to the water control, which led to 23% mortality. Steinernema feltiae and H. bacteriophora survival was 100% when exposed to adjuvants, except S. feltiae with glycerin and H. bacteriophora with flame retardant. Further research to evaluate the efficacy of EPN and adjuvants under field conditions is necessary

Catch me if you can: the influence of refuge / trap design, previous feeding experience, and semiochemical lures on vine weevil (Coleoptera: Curculionidae) monitoring success

BACKGROUND Vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae), is one of the most economically important pest species of berry and ornamental crops globally. Monitoring this nocturnal pest can be difficult and time consuming and the efficacy of current tools is uncertain. Without effective monitoring tools, implementation of integrated pest management strategies is challenging. This study tests the relative efficacy of a range of vine weevil monitoring tools. Whether host‐plant volatiles and weevil feeding experience influence vine weevil capture is also tested. RESULTS Monitoring tool efficacy differed overall between the six monitoring tool designs tested and ranged from catches of 0.4 % to 26.7 % under semi‐field conditions. Previous feeding experience influenced vine weevil behaviour. In yew conditioned populations, 39 % of the weevils responded to and were retained in the trap baited with yew foliage while 37 % of weevils from Euonymus fortunei conditioned populations responded to and were retained in the trap baited with E. forunei foliage. A simple synthetic lure consisting of (Z)‐2‐pentenol + methyl eugenol also increased vine weevil catches compared with an unbaited trap. CONCLUSION Demonstrating differences in the efficacy of different monitoring tool designs is an important first step for developing improved methods for monitoring vine weevil populations within crops. This study presents the first direct comparison of vine weevil monitoring tool designs and indicates that trap efficacy can be improved by baiting with host‐plant material or a synthetic lure based on host‐plant volatiles

Abundance and phenology of two pest species, Cacoecimorpha pronubana and Epiphyas postvittana (Lepidoptera: Tortricidae)

Cacoecimorpha pronubana (Hübner, [1799]) and Epiphyas postvittana (Walker, 1863) are economically important polyphagous pest species. The larvae of these moths affect a wide range of horticultural crops. We evaluated the seasonal abundance and population dynamics of these two species, hypothesising that both species of moth exhibit similar patterns in their seasonal abundance and respond to abiotic factors. The study was carried out on a wide range of protected ornamental crops grown on a total area of one hectare at a commercial nursery. The study was completed over 5 consecutive years from 2015 to 2019, where both populations were monitored weekly during the months of moth activity, from April to November, using sex pheromone traps to trap the males of both species. The timing and abundance of catches were analysed in relation to local meteorological data. The mean yearly abundance of adult males was 604 ± 23.89 (mean ± SE; C. pronubana) and 1706 ± 167.18 (E. postvittana) also differing significantly between years for both species. There was no influence of any weather measures on the abundance of E. postvittana, but sunshine duration (4.84 ± 0.26 h) and temperature (13.04 ± 0.57°C) affected the mean seasonal abundance of C. pronubana. There was an overall difference in the seasonal pattern of abundance between the species studied. While we demonstrate a seasonal abundance difference between years for C. pronubana, we found no significant seasonal differences for E. postvittana. Improved understanding of seasonal abundance, phenological patterns and inter‐seasonal variations in population dynamics of these two species may be useful in developing forecasting models that can be used in improving integrated pest management strategies for these two pests

Radio stars and exoplanets at low-frequencies: first detections

Stars and planetary system