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Spring oilseed rape is severely affected by early season herbivory of various flea beetle species. Flea beetle pest management strategies with less reliance on conventional chemical insecticides are direly needed. However, the current knowledge of flea beetle ecologies and life cycles is insufficient to design and inform such strategies effectively. Using a combination of pitfall and emergence traps, we followed the life cycles of flea beetles in 13 spring oilseed rape fields in south central Sweden, measuring densities in three sampling seasons: spring activity at crop seedling stage, summer emergence of the new generation, and emergence of overwintered adults in the following spring in the adjacent grassy field margins. We found a strong positive relationship between densities of emerging Phyllotreta atra, P. striolata and P. undulata in summer and their densities earlier in spring. Flea beetle assemblage composition differed across the seasons, driven by changes in the relative abundances of different species. While assemblages emerging in summer were filtered for species reproducing in spring oilseed rape, assemblages emerging from the grassy field margins in the following spring were again more heterogeneous. Spring activity peaks and summer emergence peaks differed among species, with P. vittula having an earlier activity peak and emerging earlier than most other species. This knowledge of spatiotemporal habitat use can contribute to a more effective flea beetle management in spring oilseed rape. Especially summer emergence in the fields became apparent as a so far unexplored point in time to control flea beetle pests. [ABSTRACT FROM AUTHOR]

Current practices of flea beetle (Phyllotreta spp.) control in Brassica napus L. rely heavily on seed treatments and due to growing concerns regarding the safety of such treatments on non-target and beneficial insect populations, genetic resistance would be beneficial for a more balanced integrated pest management strategy. However, none of the registered B. napus. canola varieties exhibit measurable resistance to flea beetle injury. To this end, an evaluation of 14 winter-type B. napus breeding lines and 15 spring-type B. napus breeding lines for resistance to flea beetle feedings was conducted, as it was found that at least one line in each family exhibited noticeably reduced flea beetle damage compared to sister lines in a breeding nursery. The study revealed natural genetic variation within B. napus for flea beetle antixenosis which could be used by dedicated breeders to develop canola varieties with higher levels of flea beetle resistance. Data indicated that host plant resistance did not vary between feeding by newly emerged adult flea beetles in the fall and the overwintered adults in the spring in either winter-type or spring-type canola, as well as for adult feeding preferences. This indicates that favourable genes identified in in either habitat-type could be used interchangeably to confer resistance even though the flea beetle life cycle is different for each planting period, while either overwintered adults or newly emerged adults can be used to evaluate feeding damage. [ABSTRACT FROM AUTHOR]

This study investigated the effect of mixing volatile organic compounds (VOC) emitted by host and non‐host plants on the orientation of key pests of Brassicaceae. The study aimed to understand how these mixed VOCs influence pest behaviour, which could help in tailoring pest management strategies. The orientations of flea beetles, Phyllotreta spp., and the diamondback moth (DBM), Plutella xylostella, towards cabbage VOCs mixed with faba bean VOCs were assessed using Y‐tube olfactometry. The pests' preferences were measured to determine if the presence of faba bean alongside cabbage altered their olfactory orientation compared to cabbage alone. Flea beetles showed a preference for cabbage VOCs alone over the cabbage–faba bean VOC mix. For DBM, no significant preference was observed between cabbage alone and the cabbage–faba bean mix. Previous findings indicated that faba bean attracts DBM, and in this study the mixture of cabbage and faba bean appeared to be more attractive than cabbage alone. The results indicate that faba bean VOCs can deter flea beetles from cabbage, potentially offering a pest management strategy. However, the effect on DBM was inconclusive, with no clear preference observed. This suggests that while faba bean VOCs may influence pest orientation, their effectiveness varies among different pest species. Additionally, herbivore damage to cabbage leaves did not appear to influence the odour‐guided orientation of either pest, irrespective of the presence or absence of faba bean. [ABSTRACT FROM AUTHOR]

AbstractIn earlier studies, it was found that Leptosphaeria maculans could readily infect canola via fresh wounds but would require extended leaf wetness to infect intact tissues. We hypothesized that flea beetle feeding wounds might facilitate L. maculans infection under field conditions. Multi-year plot trials were conducted in western Canada to assess the effect of reducing flea beetle feeding wounds on canola seedlings with in-crop insecticide on subsequent blackleg infection. The experiment encompassed susceptible and resistant cultivars seeded into canola stubble from the previous year, with pyrethroid insecticide applied weekly commencing at trace feeding (<5%) to mitigate the insect damage. Fluopyram seed treatment was used as an additional treatment against early blackleg infection. Results from eight station years showed moderate feeding damage by flea beetles and generally high blackleg pressure, with the average disease incidence > 80%. Despite reduced feeding damage due to in-crop insecticide treatment, significant blackleg reduction was not observed. A greenhouse study revealed no correlation between puncture wounds on cotyledons and successful stem infection under high-inoculum conditions, suggesting that reduced insect feeding might not effectively counteract the heavy inoculum pressure resulting from canola residue in field trials. Fluopyram seed treatment did not reduce blackleg substantially, while resistant cultivars consistently exhibited effectiveness. Furthermore, harvested seed from plots with lighter blackleg often displayed lower levels of L. maculans inoculum contamination. [ABSTRACT FROM AUTHOR]

A new species, Podontia rustiai Calcetas and Staines (Coleoptera: Chrysomelidae: Galerucinae: Alticini) in the Philippines, is described. The species Podontia flava Baly, 1865 is very similar and known from Borneo (Sarawak, Sabah) and Brunei is redescribed, and the introduced Podontia quatuordecimpunctata (L., 1767) is contrasted and compared. However, the endophallic median sclerite of the paramere of the male genitalia in P. flava is whip-like and apically tapered, whereas it is shield-like and apically rounded in P. rustiai new species. A key to the genus Podontia in the Philippines and Sarawak is provided. [ABSTRACT FROM AUTHOR]

Canola (Brassica napus L.) production is threatened by blackleg disease caused by Leptosphaeria maculans. Disease outcome is determined by interactions among pathogens, plants, farming practices, and environmental factors. Although the gene-for-gene interactions between the pathogen and its plant host are relatively clear, how precisely the pathogen interacts with the environment and farming practices is still poorly understood, making disease forecasting challenging for commercial farmlands. In recent years, artificial intelligence (AI) has been successful in forecasting disease risks based on environmental factors. In this study, we evaluated two AI methods and a data augmentation method to forecast disease risk using a dataset collected from 116 farmlands in Alberta in 2021 and 2022. We first assessed a machine learning model (support vector machine or SVM) and a deep-learning model (convolutional neural network or CNN) to predict blackleg severity based on five weather variables, flea beetle damage, root maggot damage, and crop-rotation variables. Both SVM and CNN predicted the disease risk with an accuracy of over 66%. The data augmentation method did not improve model performance. Flea beetle feeding and maggot damage contribute little to the model's performance, and omitting these data did not appear to affect the results. In contrast, crop rotation contributes substantially to model performance. The five weather variables contribute roughly equally to the model's performance, and removing any of the individual weather variables did not impact prediction ability for both models. [ABSTRACT FROM AUTHOR]

We present a genome assembly from an individual female Crepidodera aurea (flea beetle; Arthropoda; Insecta; Coleoptera; Chrysomelidae). The genome sequence is 509.0 megabases in span. Most of the assembly is scaffolded into 10 chromosomal pseudomolecules, including the X sex chromosome. The mitochondrial genome has also been assembled and is 18.69 kilobases in length. Gene annotation of this assembly on Ensembl identified 19,944 protein coding genes.

Reliably predicting pest damage would allow farmers to reduce insecticide use without incurring economic losses and thus contribute to agricultural sustainability. However, means to predict pest severity are lacking.We assessed whether crop feeding injury caused by flea beetles in spring oilseed rape can be predicted from flea beetle pest densities in the previous season using 22 years of suction trap catches of flea beetles in combination with crop feeding injury data from 293 fields.We found a strong positive relationship between the densities of flea beetles of the genus Phyllotreta in the summer and autumn activity period of the previous year and crop feeding injury caused by flea beetles in spring oilseed rape the following year. Autumn weather or the total cover of spring oilseed rape in the study region did not improve the prediction further.Pest monitoring using suction traps is thus a promising tool to predict crop feeding injury and can reduce insecticide use in years with low pest pressures. [ABSTRACT FROM AUTHOR]

Ecological niche models of species occurrence have gained interest in biological control programs to improve efficiency, reduce risks, and to inform when and how control agents may be released and/or surveyed. Alligator weed, Alternanthera philoxeroides (Mart.) Griseb. (Amaranthaceae), is an amphibious aquatic plant native to southern South America that has invaded several countries around the world. In this study, our aim was to quantify the current and to model the future alligator weed geographical distributions in its native range in South America, and in its introduced range (USA, the country where biological control of the weed was first implemented). Additionally, we modelled the current and potential distribution of its biocontrol agent Agasicles hygrophila Selman & Vogt (Coleoptera: Chrysomelidae), released in the USA in 1964, and other potential biocontrol agents, including the flea beetles Disonycha argentinensis Jacoby and Systena sp. In total, 19438 occurrence records of alligator weed, 253 of A. hygrophila, 48 of D. argentinesis, and 19 of Systena sp. were compiled. Niche models predicted expanded distributions of alligator weed, particularly in northern regions of South America. However, the models of the flea beetles A. hygrophila, D. argentinensis, and Systena sp. did not predict geographic range expansion and the future scenarios are similar to current distributions. Our study predicts an increase in the suitable areas for alligator weed in South America in future scenarios of global warming, whereas these new areas would not be as favourable for the biocontrol agents historically used. [ABSTRACT FROM AUTHOR]

Longitarsus ferruginipennis Fuente 1910 was described from Ciudad Real, Spain. Later, it was regarded a senior synonym of L. seticollis Mohr 1962. No other information about this species is available. In the current study, we compare the two species, concluding that they are different. A redescription of L. ferruginipennis and a new distributional record are given, as well as host plant and habitat data. Photographic images of the habitus and genitalia of the two species are shown.

In an experiment conducted during rabi 2021-22 and 2022-23 at Horticulture Research and Extension Centre, Vijayapur (Tidagundi), Karnataka, India, to assess the impact of Cyantraniliprole 10.26% OD against grape insect pests. Among the different insecticides with different modes of action, Cyantraniliprole 10.26% OD @ 70 g a.i./ha recorded significantly lowest thrips (6.73/three leaves), leafhoppers (5.20/three leaves), mealy bugs (92.00/vine) and flea beetles (1.93/vine) followed by, Imidacloprid 17.8 SL @ 71.8 g a.i./ha with 7.67 thrips/three leaves, 5.33 leafhoppers/three leaves, 94.20 mealy bugs/vine and 2.53 flea beetles/vine during 2021-22. Further, Cyantraniliprole 10.26% OD @ 70 g a.i./ha was found to be safer to predators in grape ecosystems with no considerable impact on their survival during 2021-22. A similar trend was noticed during rabi 2022-23 also. [ABSTRACT FROM AUTHOR]

A field experiment was conducted to evaluate the efficacy of insecticides against foliage feeding beetles viz., Henosepilachna vigintioctopunctata F. and potato flea beetle, Epitrix cucumeris on potato (Solanum tuberosum L.) during Rabi, 2019-20 and 2020-21 at Odisha University of Agriculture and technology (OUAT), Bhubaneswar, India. The treatments consisted of azadirachtin 0.03% w/w@1500ml/ha, cypermethrin 25% EC @200ml/ha, fipronil 5% SC@1000ml/ha, spinosad 45% SC @187.5ml/ha, cartap hydrochloride 50% SP @1000g/ha, chlorpyriphos 20% EC @2000ml/ha and untreated control. The results revealed that, cartap hydrochloride 50% SP @1000g/ha was found to be most effective against epilachna beetle (0.7beetles/plant) and flea beetle (0.8beetles/plant) with 85.41% and 82.98% reduction over control and also recorded maximum potato tuber yield (14.1t/ha) with 48.42% yield improvement over untreated control. [ABSTRACT FROM AUTHOR]

Podontia quatuordecimpunctata (L.) or the "sineguelas" leaf beetle is reported from the Philippines. Red sineguelas (Spondias purpurea L.), golden apple or yellow sineguelas (S. dulcis Forst.), and hog plum or "libas" [S. pinnata (L.f.) Kurz.] are reported as host plants. However, feeding on S. philippinensis (Elm.) and S. mombin L. (hog plum are unverified. The current geographic distribution and pest status of P. quatuordecimpunctata are presented. [ABSTRACT FROM AUTHOR]

The flea beetle, Altica cirsicola, escapes predators by jumping and landing in a dense maze of leaves. How do they land on such varied surfaces? In this experimental study, we filmed the take-off, flight, and landing of flea beetles on a configurable angled platform. We report three in-flight behaviors: winged, wingless, and an intermediate winged mode. These modes significantly affected take-off speed, acceleration, and the duration that wings were deployed. When wings were closed, flea beetles rolled or pitched up to five times in the air. This work may help to understand how insects can jump and right themselves onto variable surfaces. [ABSTRACT FROM AUTHOR]

Intensive and extensive cultivation of grapes leads to a serious pest problem in major grape-growing areas of the world. The climate in India is ideally suited for the high production of table and wine grapes as well as a high prevalence of several pests. Among different insect pests, adult flea beetles are observed from mid-July and reach peak numbers in October-November and cause damage to the plants immediately after pruning in October. The loss increases to 50 per cent when the sprouting buds are damaged, particularly after October pruning. Several newer molecules and botanical insecticides were evaluated against grape flea beetle at Horticulture Research and Extension Centre, Vijayapur (Tidagundi), Karnataka, India during 2020-21. Among the insecticides, Lambda-cyhalothrin 5 EC @ 0.50 ml/l recorded the lowest number of flea beetles and bud damage followed by Lambda-cyhalothrin 4.9 CS @ 0.50 ml/l, Fipronil 80 WG @ 0.06 g/l, Spinosad 45 SC @ 0.25 ml/l, Cyantraniliprole 10.26 OD @ 0.70 ml/l, Thiamethoxam 25 WG @ 0.25 g/l, Flonicamid 50 WG @ 0.30 g/l, and Alphamethrin 10 EC @ 0.50 ml/l. Finally, the significantly highest marketable yield (t/ha) was also recorded in the treatment Lambdacyhalothrin 4.9 CS @ 0.50 ml/l (42.82 t/ha) followed by Cyantraniliprole 10.26 OD @ 0.70 ml/l, Fipronil 80 WG @ 0.06 g/l, Alphamethrin 10 EC @ 0.50 ml/l, Lambda-cyhalothrin 5 EC @ 0.50 ml/l, Thiamethoxam 25 WG @ 0.25 g/l, Spinosad 45 SC @ 0.25 ml/l, Flonicamid 50 WG @ 0.30 g/l and Azadirachtin 1 EC @ 2.00 ml/l (40.46, 40.32, 39.88, 39.15, 37.73, 37.61, 36.96 and 31.15 t/ha, respectively). [ABSTRACT FROM AUTHOR]

In Burkina Faso, the leaf beetle Aphthona whitfieldi is the main insect pest of the biofuel plant Jatropha curcas that affects plant growth and seed yield. This study was conducted on-station and on-farm in the district of Léo, southern Burkina Faso, in 2015. It aimed at evaluating the yield losses that A. whitfieldi inflicts to J. curcas. The first experiment used 25 caged trees during the first year of fruit production, on which various numbers of beetles were released. When 200 beetles were released/cage, the defoliation level reached 55% and caused 61% of yield loss. Releases of 400 or more beetles/cage caused a defoliation level of at least 74% and seed losses of 99%. On-farm observations were made on foliage damage and yield loss in three different types of plantations, i.e. sole plantations, plantations intercropped with food crops and hedges. These observations showed that defoliation levels over 50% were common in the three types of plantations, resulting in very low yields. This study shows the importance of beetle damage in the cultivation of J. curcas. It highlights the leaf beetle as main limiting constraint for the production of J. curcas in Burkina Faso. [ABSTRACT FROM AUTHOR]

Aestivation is a form of seasonal dormancy observed in various insect species, usually coinciding with the summer season. The cabbage stem flea beetle, Psylliodes chrysocephala (Coleoptera: Chrysomelidae), is a key pest of oilseed rape that obligatorily aestivates as adult in late summer. Since the physiological and transcriptional processes linked to aestivation in P. chrysocephala are still little understood, we analyzed relevant physiological parameters and performed RNA-seq analyses on laboratory-reared beetles in their pre-aestivation, aestivation, and post-aestivation stages. We found that the beetles reached aestivation at 15 days post-eclosion, showing strongly reduced metabolic activity, with less than 50% CO 2 production, compared to pre-aestivating individuals. Under constant laboratory conditions, the beetles aestivated for about 25 days. Female beetles reached reproductive maturity at a median of 52 days post-eclosion. Furthermore, aestivating beetles had significantly reduced carbohydrate reserves and increased lipid reserves compared with pre-aestivating beetles, indicating that aestivation is associated with drastic changes in energy metabolism. Aestivating beetles contained 30% less water and their survival rates under high-temperature conditions (30 °C) were 40% higher compared to pre-aestivating beetles. RNA-seq studies showed that, in particular, gene ontology terms related to carbohydrate and lipid metabolism, digestion, and mitochondrial activity were enriched, with clear differences in transcript abundance between beetles in aestivation compared to pre- or post-aestivation. Specifically, mitochondrial transcripts, such as respiratory chain I subunits , and digestion-related transcripts, such as trypsin , were less abundant during aestivation, which supports the idea that aestivation is associated with decreased metabolic activity. This study represents the first exploration of the transcriptomic and physiological processes linked to aestivation in P. chrysocephala. [Display omitted] • P. chrysocephala obligatorily aestivate as sexually immature adults in summer. • Aestivation entails metabolic suppression, composition changes, and stress resistance. • Accordingly, metabolism and stress genes were differentially expressed. • The findings can support the development of innovative pest management strategies. [ABSTRACT FROM AUTHOR]

Blackleg, caused by the fungus Leptosphaeria maculans, is an important disease of canola. Both ascospores and pycnidiospores of the fungus can infect intact leaves under conditions of extended leaf wetness, with infection then progressing further into the stem. In western Canada, spring is typically cool and dry and additional factors may be involved for successful infection. This study was designed to assess the effect of wounding and wound age on cotyledon infection, to evaluate the likelihood that flea beetle-feeding injuries could contribute to increased disease. Infection of canola cotyledons occurred readily via mechanical wounds in the absence of leaf wetness when seedlings were spray inoculated with pycnidiospores of L. maculans, whereas no infection occurred on intact cotyledons even under 6-h leaf wetness. Wound age also played a role in susceptibility; wounded tissues were less susceptible when plants were kept in a greenhouse for 8 h or longer before inoculation, with substantially reduced infection success relative to fresh wounds. This wound-age effect was similar on susceptible and resistant canola varieties. A high temperature (25°C) seemed to favour the healing of wounds, reducing susceptibility when compared with control (21/16°C) and low (10°C) temperatures. Leaf wetness post-wounding may hinder healing, and high post-inoculation humidity (80–90% relative humidity) increased infection via older wounds slightly, relative to lower (50–60%) relative humidity. These data provide a rationale for studying the effect of improved flea beetle control on early L. maculans infection of canola. [ABSTRACT FROM AUTHOR]

Pollination and pest control are two major ecological functions sustaining crop yield. In insect‐pollinated crops, previous studies have revealed that an increase in resources and habitats in landscapes can increase pest control by natural enemies as well as insect pollination by pollinators. However, data have been lacking that simultaneously considers the effects of landscape on both pollinators and pests, and the direct and indirect effects on yields of farming practices interacting with landscape, bees and pests.This study aimed to fill this gap by focusing on oilseed rape (OSR), an insect‐pollinated crop of high economic value. We first quantified the effects of landscape and farming practices on both bee and pest abundance caught in OSR blooming season in 124 farmed fields over a 6‐year study (~20 fields sampled per year), and then used structural equation modelling to assess the direct and indirect links between bees, pests, farming practices and landscape on yield.The results showed that landscape had a stronger effect on bee and pest abundance than agrochemical farming practices. Bees and pests decreased with the amount of OSR in the landscape surrounding the focal field, and showed contrasted effects with the amount of meadow and organic farming: positive for bees and negative for pests. Bee abundance also increased with the amount of sunflower in the landscape the preceding year, and decreased with increasing field size.While agrochemicals surprisingly had barely any effect on bees and pests, their use improved OSR yield, although at a similar magnitude as bee and pest abundances.Synthesis and application. This study, conducted in commercial crop fields, underlines the important contribution of sustainable landscape management for enhancing OSR yield. Despite agrochemicals' ability to improve or maintain OSR yields, their unconditional use is unsustainable due to negative externalities. Therefore, alternative options such as those highlighted in our study—such as reducing field size, increasing the amount of organic farming in the landscape, or sowing OSR in landscapes rich in sunflowers the preceding year—appear to be relevant tools to promote ecosystem services, maintain yield and conserve biodiversity. These findings support the potential of nature‐based solutions to foster more sustainable agriculture. [ABSTRACT FROM AUTHOR]

Mungbean is one of the important pulse crops in Bangladesh. More than 12 species of insect pests infest mungbean, among them flea beetle cause significant yield loss due to attack from seedling to vegetative stages. The experiment was conducted to find out tolerant and susceptible varieties of mungbean against flea beetle at the farmer’s field of Patuakhali, Bangladesh from January to April 2016. Results revealed that BARI Mung-4 had the lowest abundance of flea beetle while BINA Moog-7 and BARI Mung-6 had the highest flea beetle abundance. Among the tested all varieties, significantly the lowest number (1.33) of infested plant by flea beetle was recorded in BARI Mung-4 followed by BINA Moog-4 (1.51) and the highest number (2.54) of infested plant by flea beetle was in BARI Mung-6 followed by (2.42) BINA Moog-7. The lowest percentage of leaf area damaged was on BARI Mung-4 (5.37%) while the highest on BARI Mung-6 (11.33%). Population of flea beetle showed a positive correlation (R2= 0.019) with temperature and a negative correlation (R2= -0.01) with relative humidity. BARI Mung-6 produced highest yield while Patuakhali local Mung produced the lowest followed by BARI Mung-4. Among tested varieties BARI Mung-4 showed comparatively more tolerant against flea beetle and BARI Mung-6 produced maximum yield in spite of being susceptile to flea beetle.

Flea beetles are common pests of vegetables, fruits, grains and other crops. The aggregation pheromone components of flea beetles, including fourteen sesquiterpenes and six unsaturated aldehydes, can be used for mass trapping and monitoring. It is a promising technology for control of flea beetles. The syntheses of the sesquiterpenes were described according to the strategies for the construction of chiral center, which consisted of chiral sources, enantioinduction and asymmetric catalytic reactions; whereas the preparations of unsaturated aldehydes were reviewed on basis of the approaches for constructing carbon-carbon double bonds, including aldol condensation, Wittig coupling, Wittig-Horner coupling and acetylenic ester isomerization. Moreover, the advantages and disadvantages of each method were discussed, as well as the prospects for the synthesis of aggregation pheromones of flea beetles. [ABSTRACT FROM AUTHOR]

The Ebony series of crepe myrtle (Lagerstroemia indica) cultivars includes several (Ebony Embers, Ebony Fire, Ebony Flame, Ebony Glow, and Ebony and Ivory), marketed today under the Black Diamond® brand. These are relatively new crepe myrtle cultivars unique for their dark foliage, but with little information concerning their performance in north-central Texas, especially in low-input landscapes. The study was conducted from 2014 to 2017 at three locations in north-central Texas with three soil types, an acidic fine sandy loam, a neutral pH silt loam, and an alkaline heavy clay. Although soils and environmental conditions caused variations between sites, overall performance among cultivars was consistent across all study sites, with Centennial Spirit having better landscape performance than any of the Ebony cultivars tested. ‘Ebony and Ivory’ and ‘Ebony Blush’ had the overall lowest landscape performance. Ebony cultivars grew more slowly, had fewer blooms, and were more susceptible to powdery mildew than Centennial Spirit. While the trees may perform better in more intensively managed landscapes, the Ebony cultivars did not perform as well as Centennial Spirit in low-input landscapes in north-central Texas.

Experiment was conducted at the Agricultural Farm of Patuakhali Science and Technology University to know the morphological characteristics of different mutants of mungbean and to find out tolerant/least susceptible mutant(s) against flea beetle, aphid and pod borer based on the reaction of insect pests to promising mutants of mungbean during the period from April to June, 2015. The mutant MBM-07(S)-2 was found to be the tallest (32.57 cm) with highest number of branches/plant (5.03), highest number of leaves/plant (11.06) among all mutants and check variety while MBM-07-Y-2 (23.4 cm) was the shortest plant height, MBM-656-51-2 had the lowest number of branches/plant (3.73), MBM-347-13 (7.03) had the lowest number of leaves/plant. The mutant MBM-427-87-3 had the highest number of pods (5) compared to other mutants but MBM-656-51-2 had the lowest number of pods/plant (3.09). Mutant MBM-347-13 had the lowest population of flea beetle (18) and pod borer (2) compared to all other mutants while the lowest number of aphid/plant was observed in mutant MBM-07-Y-1 (1). In case of infestation, the mutant MBM-347-13 had the lowest percentage of infestation (20.69%) by flea beetle, (3.18%) by pod borer but the lowest infestation by aphid (3.33%) was recorded in the mutant MBM-390-94-Y while the mutant MBM-427-87-3 had the highest percentage of plant infestation (37.8%) by flea beetle, pod damage (9.69%) by pod borer and variety BARI moog-6 had the highest percentage (34.45%) of plant infestation by aphid. Mutant MBM-347-13 was least susceptible to flea beetle and pod borer while mutant MBM-427-87-3 was highly susceptible to flea beetle and pod borer. However, mutant MBM-390-94-Yand MBM-07-Y-2 were less susceptible to aphid while BARI moog-6 and mutant MBM-427-87-3 were highly susceptible to aphid. [ABSTRACT FROM AUTHOR]

Background: The univoltine leaf beetle Psylliodesattenuata (Koch, 1803) is a pest of Cannabis and Humulus (Cannabaceae) and native to the Palaearctic Region, known from eastern Asia to western Europe., New Information: First North American records are presented for P.attenuata from Canada: Ontario and Québec. Adult beetle feeding damage to hops Humuluslupulus L. (Cannabacaea) plants is recorded from Québec. Diagnostic information is presented to distinguish P.attenuata from other North American Chrysomelidae and a preliminary assessment of its potential to spread in North America is presented. While our climate analysis is limited by a lack of data, it appears P.attenuata is physiologically capable of persisting throughout the range of Humulus in North America.The United States of America and Canada are now known to be home to 71 or more species of adventive Chrysomelidae.

We present a genome assembly from an individual female Crepidodera aurea (flea beetle; Arthropoda; Insecta; Coleoptera; Chrysomelidae). The genome sequence is 509.0 megabases in span. Most of the assembly is scaffolded into 10 chromosomal pseudomolecules, including the X sex chromosome. The mitochondrial genome has also been assembled and is 18.69 kilobases in length. Gene annotation of this assembly on Ensembl identified 19,944 protein coding genes., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Telfer MG et al.)

Fifteen varieties of mungbean were evaluated for resistance against major insect pests i.e., leaf folder (Cnaphalocrocis medinalis), flea beetle (Phyllotreta nigripes), thrips (Megalurothrips distalis), gram pod borer (Helicoverpa armigera) and legume pod borer (Maruca vitrata). Screening was done on the basis of incidence of insect pests from first incidence upto harvest. Statistically significant variation on recorded data was observed at different days after sowing. The lowest leaf folder population was recorded on variety BARI Mung-4 (1.08 larvae per plot) while the highest (2.05) on variety BARI Mung-6. The flea beetle population was the lowest on variety BARI Mung-4 (1.67 flea beetles per plot) while the highest (3.04) was recorded on variety BARI Mung-6. The lowest population of thrips was observed on variety BARI Mung-4 (1.43 thrips per 10 opened flowers) and the highest population (2.67) was observed on variety BINA Moog-7. The lowest gram pod borer population was observed on variety BARI Mung-4 (1.03 caterpillars per plot) while the highest gram pod borer population was observed on variety BARI Mung-6 (2.24). The lowest population of legume pod borer was observed on variety BINA Moog-4 (1.18 larvae per plot) while the highest population (2.75) was recorded on variety BARI Mung-6. Among the tested varieties, BARI Mung-4 was proven comparatively the least pest infested and highest resistant variety. On the contrary, BARI Mung-6 showed least resistance. Rest of the varieties expressed moderately resistance to major insect pests. The results showed that none of the tested varieties was completely resistant to major insect pests. [ABSTRACT FROM AUTHOR]

Studies on seasonal incidence of flea beetle were carried out during post-kharif and pre-kharif seasons using the cultivar Bhindi No. 10. The results revealed that the activity of the flea beetle was more during pre-kharif season in comparison to post-kharif season. The peak incidence of flea beetle (1.37/plant) was observed in 47th meteorological standard week (MSW) during post-kharif season, and during pre-kharif season the peak incidence of flea beetle (1.40/plant) was observed in the 18th MSW. Weather played an important role in both post-kharif and pre-kharif seasons under study. During post-kharif season, flea beetle population had a significantly negative correlation with maximum and minimum temperature of all weeks. During prekharif season flea beetle population exhibited non-significant and positive influence with all environmental parameters of all the weeks except morning RH of 1-lag and 2-lag week which showed a negative and non-significant effect. [ABSTRACT FROM AUTHOR]

An experiment was conducted during rabi 2016-17 and 2017-18 at Kankatta Village in Bidar district, Karnataka, India, to evaluate the bioefficacy of Tolfenpyrad 15% EC against grape insect pests. Among the different insecticides with different modes of action, Tolfenpyrad 15% EC @ 150 g a.i./ha recorded significantly lowest thrips (6.73/three leaves), leafhoppers (5.20/three leaves), mealy bugs (92.00/vine) and flea beetle (1.93/vine followed by, Imidacloprid 17.8 SL @ 71.8 g a.i./ha with 7.67 thrips/three leaves, 5.33 leafhoppers/three leaves, 94.20 mealy bugs/vine and 2.53 flea beetle/vine. Further, Tolfenpyrad 15% EC @ 150 g a.i./ha was found to be safer to predators in grape ecosystem with no considerable impact on their survival. Similar trend was noticed during rabi 2017-18 also. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Societe Vaudoise des Sciences Naturelles is the property of Societe Vaudoise des Sciences Naturelles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Previously, transgenic trichome-bearing (hairy leaf) Brassica napus lines expressing either the Arabidopsis thaliana GL3 gene (line AtGL3+) [1] or the AtGL3 gene in combination with an RNAi construct to down-regulate TTG1 (line K-5-8) [2] were developed. The leaves of these lines exhibited altered insect feeding (flea beetle) and oviposition (diamondback moth) behaviour compared to the non-transgenic semi-glabrous leaves of B. napus cv. Westar. Interestingly, the cotyledons of these lines remained glabrous, but also showed reduced feeding by flea beetles. Here we examine the composition and global transcriptome of the glabrous cotyledons from these transgenic lines to ascertain the mechanism(s) underlying this unexpected phenomenon. Results Approximately, 7500 genes were up-regulated in cotyledons of each hairy line, compared with

A new species of Dysphenges Horn, 1894 is described from Guatemala. Dysphenges vittatus (Jacoby, 1891), new combination, is transferred from Cyrsylus Jacoby, 1891. Habitus and male genitalia images are provided for both species, and a revised key to the known species of Dysphenges is provided. [ABSTRACT FROM AUTHOR]

Flea beetles, are common pests of cabbage Brassica oleracea L. (Brassicales: Brassicaceae) and eggplant Solanum melongena L. (Solanales: Solanaceae), but little is known about the flea beetle populations in Virginia, their impact on yield, or the most effective control methods. This research investigates flea beetle populations and the impact of their feeding injury on cabbage and eggplant in Southwest Virginia and determines the most efficacious control methods. In Whitethorne, VA, cabbage and eggplant crops were vacuum sampled weekly throughout two summers (2015, 2016). Crucifer flea beetle, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae), and striped flea beetle, Phyllotreta striolata Fabr. (Coleoptera: Chrysomelidae) were found on cabbage; whereas, eggplant flea beetle, Epitrix fucula (Crotch) (Coleoptera: Chrysomelidae), and the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) (Coleoptera: Chrysomelidae) were found on eggplant. To evaluate the impact of flea beetle feeding on these plants flea beetle densities and defoliation were assessed weekly and individual plant, as well as whole plot yields, assessed at harvest. For cabbage, significant yield reductions were observed between 1 and 20% and >60% defoliation. Similarly, significant yield reductions were observed between 41 and 60% and >60% defoliation for eggplant. The efficacy of various insecticides was also evaluated. Soil application of the systemic neonicotinoid dinotefuran, imidacloprid, and the foliar-applied bifenthrin resulted in the fewest beetles, the least amount of leaf defoliation, and the highest yield in cabbage and eggplant. This research helps vegetable growers to better understand the severity of these pests and how to effectively combat them. [ABSTRACT FROM AUTHOR]

Agasicles hygrophila has been introduced worldwide as a control agent for the invasive weed Alternanthera philoxeroides. However, global warming has potential impact on its controlling efficacy. The aim of this research was to explore the primary factors responsible for the greatly reduced A. hygrophila population in hot summers. To imitate the temperature conditions in summers, different developmental stages of A. hygrophila were treated with high temperatures from 32.5 °C to 45 °C for 1–5 h. Based on the survival rate, the heat tolerance of each developmental stage was ranked from lowest to highest as follows: egg, 1st, 2nd, 3rd instar larva, adult and pupa. Eggs showed the lowest heat tolerance with 37.5 °C as the critical temperature affecting larval hatching. Heat treatment of the A. hygrophila eggs at 37.5 °C for 1 h decreased the hatch rate to 24%. Our results indicated that when compared with the control at 25 °C, 1 h treatment at 37.5 °C prolonged the duration of the egg stage, shortened the duration of oviposition and total longevity, and changed the reproductive pattern of A. hygrophila. The net reproductive rate, intrinsic rate and finite rate were all significantly reduced. The results suggest that low heat tolerance of the eggs was the major factor responsible for the reduction of A. hygrophila populations, and the key temperature was 37.5 °C. Therefore, appropriate measures should be taken to protect eggs in order to maintain the efficacy of A. hygrophila in the biological control of A. philoxeroides in hot summers. [ABSTRACT FROM AUTHOR]

Alligator weed (Alternanthera philoxeroides (Martius) Grisebach) is an amphibious invasive plant native to South America. It is an allopolyploid that, in Argentina, possess two cytotypes, tetraploids and hexaploids. In the exotic range, the plant is biologically controlled with flea beetle Agasicles hygrophila Selman and Vogt but with different levels of success. The genotype of host plant is an important factor that needs to be considered in biological control programs. We studied how alligator weed ploidy level affects the oviposition preferences of A. hygrophila and its relation with female feeding preference, egg survival and larval performance in its native range. Females recognized the different ploidy levels of alligator weed and preferred to lay eggs on hexaploids than tetraploids. This choice positively affected larval performance and may be explained by the preference–performance hypothesis in this case for different plant cytotypes. Polyploidy should be considered in evaluating and prioritising biological control agents. [ABSTRACT FROM AUTHOR]

β-Glucosidases play an important role in the chemical defense of many insects by hydrolyzing and thereby activating glucosylated pro-toxins that are either synthesized de novo or sequestered from the insect's diet. The horseradish flea beetle, Phyllotreta armoraciae , sequesters pro-toxic glucosinolates from its brassicaceous host plants and possesses endogenous β -thioglucosidase enzymes, known as myrosinases, for glucosinolate activation. Here, we identify three myrosinase genes in P. armoraciae (PaMyr) with distinct expression patterns during beetle ontogeny. By using RNA interference, we demonstrate that PaMyr1 is responsible for myrosinase activity in adults, whereas PaMyr2 is responsible for myrosinase activity in larvae. Compared to PaMyr1 and PaMyr2 , PaMyr3 was only weakly expressed in our laboratory population, but may contribute to myrosinase activity in larvae. Silencing of PaMyr2 resulted in lower larval survival in a predation experiment and also reduced the breakdown of sequestered glucosinolates in uninjured larvae. This suggests that PaMyr2 is involved in both activated defense and the endogenous turnover of sequestered glucosinolates in P. armoraciae larvae. In activity assays with recombinant enzymes, PaMyr1 and PaMyr2 preferred different glucosinolates as substrates, which was consistent with the enzyme activities in crude protein extracts from adults and larvae, respectively. These differences were unexpected because larvae and adults sequester the same glucosinolates. Possible reasons for different myrosinase activities in Phyllotreta larvae and adults are discussed. [Display omitted] • Phyllotreta armoraciae leaf beetles possess three different myrosinases. • Different enzymes are responsible for myrosinase activity in larvae and adults. • The beetle myrosinases differ in their substrate specificities. • Myrosinase activity protects larvae against a generalist predator. • Myrosinases metabolize sequestered glucosinolates in uninjured larvae. [ABSTRACT FROM AUTHOR]

Nitrogen (N) availability is an important factor affecting the canola (Brassica napus L.) yield. While N fertilization is commonly used to enhance the yield and quality of canola, it is also known to influence the incidence of insect pests in the crop. The flea beetle Phyllotreta cruciferae (Goeze) and the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsh), are two economically important pests of canola in the northern Great Plains of the United States. This study investigated the effects of N fertilization (0, 56, 112 and 168 kg/ha) with or without insecticide seed treatment application on P. cruciferae and C. obstrictus injury levels, canola seed yield, and quality in replicated field trials at the two locations (Conrad and Sweet Grass) of north central Montana. The study showed that N fertilization had no influence on P. cruciferae and C. obstrictus injury levels, regardless of the study location or sampling date. However, insecticide seed treatment application significantly influenced P. cruciferae injury ratings at the both locations. In Conrad, insecticide-treated plots had significantly lower injury levels at the four leaf, pre-flower, and pod formation stages but without an effect at the cotyledon stage of canola plants when compared with untreated control plots. Similarly, in Sweet Grass, injury levels were significantly lower in insecticide-treated plots from cotyledon to pre-flowering stages but not at the pod stage of canola plants. In contrast, insecticide seed treatment had no impact on pod infestation rates by C. obstrictus at either location. Insecticide seed treatment, averaged over all the N rates, improved canola seed yield and quality parameters compared to the untreated plots. [ABSTRACT FROM AUTHOR]

Copyright of Iheringia. Série Zoologia is the property of Fundacao Zoobotanica do Rio Grande do Sul and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Systena frontalis (F.) (Coleoptera: Chrysomelidae) is an important pest of many ornamental plants in container nurseries. Adult S. frontalis cause feeding damage on leaves and affected plants are not marketed. Systena frontalis adults are currently managed using insecticides, especially neonicotinoids, and growers are seeking alternative options as customers demand neonicotinoid-free plants after concerns associated with nontarget exposure to pollinators. Barrier fences could be an alternative tactic to protect high-value crops, such as panicled hydrangea (Hydrangea paniculata Siebold), from invading S. frontalis adults in container nurseries. Thus, the objective of this study was to determine the effect of overhang barrier fence using with and without insecticide-impregnated-netting on adult S. frontalis infestation and feeding damage on panicled hydrangea. In 2021 and 2022, a study using an overhang exclusion fence was conducted in a container nursery in Georgia, USA. The treatments were: 1) deltamethrin-impregnated enclosed barrier, 2) nontreated enclosed barrier, and 3) no barrier. Four containers of panicled hydrangea were placed in the center of each experimental plot. Both deltamethrin-impregnated and nontreated enclosed barrier treatments reduced the incidence and severity of adult feeding damage on the panicled hydrangea than no barrier treatment. There was no difference between deltamethrin-impregnated and nontreated enclosed barrier treatments. The results suggest that overhang barriers can protect container plants from invading adult S. frontalis. • Systena frontalis is a serious pest on ornamental plants in container nurseries in the eastern USA. • Overhang barrier fence reduced adult S. frontalis infestation and damage on panicled hydrangea. • Feeding damage was similar between deltamethrin-impregnated and nontreated fence barrier. [ABSTRACT FROM AUTHOR]

Amaranth (Amaranthus spp.) is an increasingly high-valued niche vegetable crop among small organic growers in North Carolina, due to its increasing demand among diverse immigrant groups. Production is however hampered by insect pests such as the flea beetle (FB), Disonycha glabrata (Coleoptera: Chrysomelidae), that cause significant yield reduction. Chemical insecticides are generally applied for pest control despite their known risks to health and the environment. Integrated pest management (IPM), which is a cost effective and environmentally friendly approach is still under-exploited in vegetable production by small growers. We studied IPM approaches, suitable for organic production of amaranth by screening nine amaranth varieties for resistance to the flea beetle (FB), D. glabrata, grown with, and without, mulch. D. glabrata population was 60% higher in plots with mulch compared to plots without. The amaranth varieties Molten fire and Green Callaloo recorded the lowest and the highest beetle population commensurate with low, and high leaf damage, respectively. Conversely, leaf yields in the mulched plots were 50% less than recorded in the zero-mulch counterpart, with Green Callaloo variety recording the lowest. These findings will serve as building blocks for a sustainable pest management plan that is appropriate for organic production of Amaranthus spp. in North Carolina.