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White grubs (Scarabaeidae: Coleoptera) are subterranean pests of several economically important crops all over the world. The phytophagous larvae from the subfamilies Melolonthinae, Rutelinae and Dynastinae attack crop roots, while the adults are defoliators that feed on plant foliage. Yield loss due to these white grubs is in the range of 12–100 per cent. This review presents a literature survey of their species diversity, bioecology and control measures to facilitate better management strategies in farming. [ABSTRACT FROM AUTHOR]

Simple Summary: Hylamorpha elegans, a native Chilean scarab beetle regarded as a significant pest, feeds on economically important crops, such as red clover, ryegrass, and wheat, in its larval stage (i.e., white grubs). Traditionally, chemical control through insecticides has been used against H. elegans without success, and alternative control strategies based on ethology and the use of semiochemicals have remained elusive. Thus, chemical communication through chemosensory genes in H. elegans could represent an advance towards integrated pest management. In this study, the repertoire of chemosensory gene candidates from white grubs of H. elegans, their phylogenetic relationships, and relative gene expression have been reported for the first time. Olfaction and gustation processes play key roles in the life cycle of insects, such as finding and accepting food sources, oviposition sites, and mates, among other fundamental aspects of insect development. In this context, chemosensory genes found in sensory organs (e.g., antennae and maxillary palps) are crucial for understanding insect behaviour, particularly the phytophagous behaviour of insect pests that attack economically important crops. An example is the scarab beetle Hylamorpha elegans, which feeds on the roots of several crops important for livestock in its larval stage. In this study, chemosensory gene candidates of H. elegans white grubs identified through the head transcriptome and phylogenetic and tissue-biased gene expression (antennae, head without antennae, and legs) have been reported. Overall, 47 chemosensory genes were identified (2 ORs, 1 GR, 11 IRs, 9 CSPs, and 24 OBPs). Gene expression analysis revealed the predominant presence of IRs in the legs, whereas ORs and the GR were present in the heads and/or antennae. Particularly, HeleOBP9 and HeleCSP2 were significantly expressed in the head but not in the antennae or legs; these and other genes are discussed as potential targets in the context of H. elegans management. [ABSTRACT FROM AUTHOR]

Olfaction and gustation processes play key roles in the life cycle of insects, such as finding and accepting food sources, oviposition sites, and mates, among other fundamental aspects of insect development. In this context, chemosensory genes found in sensory organs (e.g., antennae and maxillary palps) are crucial for understanding insect behaviour, particularly the phytophagous behaviour of insect pests that attack economically important crops. An example is the scarab beetle Hylamorpha elegans, which feeds on the roots of several crops important for livestock in its larval stage. In this study, chemosensory gene candidates of H. elegans white grubs identified through the head transcriptome and phylogenetic and tissue-biased gene expression (antennae, head without antennae, and legs) have been reported. Overall, 47 chemosensory genes were identified (2 ORs, 1 GR, 11 IRs, 9 CSPs, and 24 OBPs). Gene expression analysis revealed the predominant presence of IRs in the legs, whereas ORs and the GR were present in the heads and/or antennae. Particularly, HeleOBP9 and HeleCSP2 were significantly expressed in the head but not in the antennae or legs; these and other genes are discussed as potential targets in the context of H. elegans management.

White grubs, the immature forms of the well-known May–June beetles (Coleoptera: Scarabaeidae), are the most wide spread and destructive insect pests of many agricultural crops worldwide. White grub management in Turkey relies heavily on soil application of synthetic insecticides, with negative side effects on soil organisms. In this study, a new-designed light trap (so-called ecosav-Mns1) was evaluated for mass-trapping of adult May–June beetles in a heavy infested apple orchard located in Isparta province (in southwestern part of Turkey) during the flight period from May to September in two successive years (2020 and 2021). The trap was tested at a density of 2 traps/decare in both years. The captured beetles were counted at weekly intervals during a four-month sampling period in both years, and the efficiency of the trap was evaluated on the basis of weekly mean numbers per trap in both years. The results indicated that very high numbers of beetles were captured in the traps especially in the first year of study (118.2 adults/trap/week in 2020). The newly designed light trap captured both males and females of both species; however, in both 2020 and 2021, more males were caught in the traps. The results also showed that mass-trapping of adult May–June beetles using newly designed light trap had a pronounced effect on their subsequent larval (white grub) populations. For instance, while mean number of larvae found in the soil around the root system was 9.8/tree in May in the first year of the study, it was 3.3/tree in the same month in the second year. All the results suggested that the new-designed light trap may help prevent the root damage caused by white grubs in horticultural areas by trapping adults of May–June beetles effectively. This study demonstrated that the new-designed light trap (ecosav-Mns1) may help prevent the root damage caused by white grubs in horticultural areas by trapping adults of May–June beetles effectively. [ABSTRACT FROM AUTHOR]

From a global perspective, soil pests that attack crop roots are amongst the most economically damaging persistent, and difficult to detect and control. Herbivorous insect pests living in the soil represent a significant challenge to food security given their persistence, the acute damage they cause to plants, and the difficulties associated with managing their populations. Using belowground ecology for plant protection from root herbivores, particularly in an integrated way, is a new and challenging frontier. In this respect, the main focus is on ecological mechanisms viz., root tolerance, and root resistance via direct physical and chemical defenses particularly via primary and secondary plant metabolites released into the rhizosphere (alcohols, esters, and aldehydes) underpin host-plant location and recognition with 80% having attractant properties. Thus, investigations were conducted on varietal preference and the reaction of white grub, Holotrichia serrata during 2018-19 with different sugarcane varieties at Bellad Bagewadi, Belagavi district, Karnataka, India. Among the eight sugarcane genotypes screened against H. serrata grub. CoM 265 (0.00 grubs/m²) and CoSnk 09293 (0.67 grubs/m²) recorded a lower number of eggs and grub load coupled with a higher number of roots, maximum root length and high root biomass. [ABSTRACT FROM AUTHOR]

Abstract Background The present study was conducted to evaluate the efficacy of some eco-friendly management modules based on plant oils and Metarhizium anisopliae against a biennial white grub species, Lepidiota mansueta Burmeister (Coleoptera: Scarabaeidae) infesting potato crop in the farmer’s field at Majuli river island, Assam, India. Results Amongst all the modules evaluated against L. mansueta grubs, the pooled analysis of two years of data (2019–2020 and 2020–2021) revealed that Module-VI [presowing treatment of mustard oil cake @ 150 kg/ha + wood ash @ 150 kg/ha + panchagavya @ 3% plus the application of Metarhizium anisopliae @ 10 g/sq.m after 1st & 2nd earthing up (25 & 60 Days after Sowing (DAS))] and Module-III [presowing treatment plus soil drenching with jatropha oil @ 5 ml/lit after 1st & 2nd earthing up (25 & 60 DAS)] were significantly superior and statistically at par over the rest of the modules in recording high yield (122.71 and 121.50 q/ha, respectively), minimum per cent tuber damage on weight basis (11.32 and 11.82%, respectively) and number basis (14.07 and 14.78%, respectively). The maximum benefit cost ratio was recorded in Module-VI, followed by Module-III and Module- II. Conclusion All the management modules were effective, however, Module-VI and Module-III were found to be significantly superior and registered the least tuber damage on weight and number basis and the highest tuber yield compared to other modules.

Abstract Larvae of Leucothyreus spp. have been reported causing damage to several crops in Brazil. From May 2012 to April 2013, adults and immatures of Leucothyreus alvarengai Frey (Coleoptera: Melolonthidae: Rutelinae) samples were obtained from sugarcane (Saccharum officinarum L.) (Poaceae) fields in the municipalities of Naviraí and Nova Andradina, Mato Grosso do Sul, Brazil. Adults were collected with the aid of light traps, whereas immatures were sampled by opening two trench sizes (30 x 30 x 30 cm and 80 x 50 x 40 cm) in the soil, beside the plants. The collected larvae were reared in laboratory conditions, fed by sugarcane seedlings. The biological cycle of L. alvarengai was completed in 230 days, displaying three larval instars with mean size of the cephalic capsule of 1.68, 2.46, and 3.00 mm for the first, second, and third instar, respectively. Adults were collected in greater numbers in December 2012, and first-instar larvae were observed as of January 2013. Conversely, pupae were observed in the field from July 2012 to January 2013. This is the first record of larvae and adults of L. alvarengai in sugarcane fields in Mato Grosso do Sul state, contributing with the knowledge about its biology and temporal distribution in the field.

White grubs cause serious yield losses in high-value crops, mainly sugarcane, groundnut, maize and potato, and biological control through entomopathogenic fungi and nematodes is by far the most sustainable management strategy available. In our investigations on the factors causing mortality of white grub larvae (Coleoptera: Scarabaeidae) during rearing, we found an undermined species of the soil-dwelling mite Schizoglyphus sp. associated with the grubs. This is the first report of the occurrence of this mite from India and of its association with scarab larvae. The potential of this mite as a biocontrol agent has to be explored. [ABSTRACT FROM AUTHOR]

Wireworms and white grubs are destructive underground pests in maize fields in China. Cyantraniliprole has good control effect on coleoptera pests. Here, we evaluated the toxicity of cyantraniliprole to the second instar larvae of Anomala corpulenta Motschulsky and third-instar of larvae of Pleonomus canaliculatus Faldermann and the effects of sublethal concentrations on the activity of antioxidant and detoxification enzymes. We also explored the efficacy of cyantraniliprole on underground pests under indoor and field conditions. The LC50 of cyantraniliprole for the third instar larvae of P. canaliculatus was 23.3712 mg/L, and that for the second instar larvae of A. corpulenta was 5.9715 mg/L. Cyantraniliprole can activate the activity of superoxide dismutase (SOD), peroxidase (POD), and glutathione S-transferase (GST) to different degrees at a sublethal dose. According to the pot experiment and the control efficacy test in the field, the indoor control effect of cyantraniliprole seed treatment on P. canaliculatus and white grubs was approximately 80%, and the maximum increase in yield achieved through cyantraniliprole application was approximately 15% in the field efficacy test. Cyantraniliprole has a strong control effect on wireworms and white grubs, so it can be used to treat seeds to control underground pests in maize fields.

Root-feeding white grubs are one of the most serious pests of honeysuckle trees (Lonicera japonica) in China, directly damaging their roots and facilitating infection by soil pathogens. Entomopathogenic nematodes (EPNs) are considered as potential control agents against soil-dwelling insect pests. This study aimed to identify effective EPN species against white grubs through bioassay and field experiments. Among the EPN species screened against Holotrichia oblita under laboratory conditions, Steinernema feltiae and Heterorhabditis indica had low virulence, while S. longicaudum, S. glaseri, and H. bacteriophora applied at a rate of 400 IJs/larva caused a higher corrected mortality (80.00 ± 5.77%), which screened them as good candidates for future applications. The field experiments showed that both S. longicaudum and H. bacteriophora were approximately as effective in reducing white grubs as the insecticide phoxim, whereas S. glaseri caused a significantly lower reduction compared with these two EPNs and phoxim. Plant mortalities obtained from S. longicaudum, H. bacteriophora and the insecticide treatment plots were significantly lower than those observed in the water-treated control plots. All EPNs examined could establish well in the treated honeysuckle fields for 42 d, confirmed by Tenebrio molitar larvae baiting technique. Our findings suggest that EPNs could provide curative efficacy against white grubs and significantly reduce plant death in honeysuckle fields.

Background: The present study was conducted to evaluate the efficacy of some eco-friendly management modules based on plant oils and Metarhizium anisopliae against a biennial white grub species, Lepidiota mansueta Burmeister (Coleoptera: Scarabaeidae) infesting potato crop in the farmer's field at Majuli river island, Assam, India. Results: Amongst all the modules evaluated against L. mansueta grubs, the pooled analysis of two years of data (2019–2020 and 2020–2021) revealed that Module-VI [presowing treatment of mustard oil cake @ 150 kg/ha + wood ash @ 150 kg/ha + panchagavya @ 3% plus the application of Metarhizium anisopliae @ 10 g/sq.m after 1st & 2nd earthing up (25 & 60 Days after Sowing (DAS))] and Module-III [presowing treatment plus soil drenching with jatropha oil @ 5 ml/lit after 1st & 2nd earthing up (25 & 60 DAS)] were significantly superior and statistically at par over the rest of the modules in recording high yield (122.71 and 121.50 q/ha, respectively), minimum per cent tuber damage on weight basis (11.32 and 11.82%, respectively) and number basis (14.07 and 14.78%, respectively). The maximum benefit cost ratio was recorded in Module-VI, followed by Module-III and Module- II. Conclusion: All the management modules were effective, however, Module-VI and Module-III were found to be significantly superior and registered the least tuber damage on weight and number basis and the highest tuber yield compared to other modules. [ABSTRACT FROM AUTHOR]

Larvae are the most important feeding and developmental stage in the life cycle of insects. Correspondingly, the larval midguts, as the primary digestive organs, undergo diverse specialization among insect lineages. Larvae of Scarabaeoidae, commomly known as white grubs, exhibit diversity on feeding habits at the familial or subfamilial level. However, the ultrastructure of larval midguts is not yet satisfactorily understood. In this study, the larval midguts of Trypoxylus dichotomus and Anomala corpulenta were compared using light and transmission electron microscopy for the first time, to uncover the ultrastructural differences between the midguts of saprophagous and phytophagous white grubs. The larval midguts of both species are tubular with three circles of the gastric caeca, and share morphological similarities in midgut epithelial cells, layers of basal lamina, and the digestive and regenerative cells. However, the midguts of the two species differ significantly in the shape of the gastric caeca and exhibit slightly differences in muscle structure. The morphology of larval midgut is related to the feeding habits. • Midgut ultrastructure of two white grubs were compared using TEM. • Larval midguts of both species have three circles of the gastric caeca. • Larval midguts of both species have wrapped muscles on ventral surfaces. [ABSTRACT FROM AUTHOR]

Scarab beetles (Coleoptera: Scarabaeidae) are a cosmopolitan group of beetles found on all continents except Antarctica. Because of their size, vibrant colors, and above all their role in the ecosystem, they are one of the most recognizable and studied taxons of beetles. Most larvae and adult beetles of species belonging to subfamilies Melolonthinae, Rutelinae, Dynastinae and Cetoniinae feed on plant organs such as roots, leaves, flowers and young fruits and are thus considered to be species of economic importance. In this article we describe some of the most economically important species of scarabs, including their most common host plants. Because the use of chemical insecticides to control scarabs is often limited, the implementation of entomopathogenic fungi as biological control agents is an appropriate alternative based on the rational use of microorganisms to maintain an environmentally balanced level of the pest population. Representatives of the genera Beauveria and Metarhizium are the most commonly used entomopathogenic fungi to control larvae (white grubs) of scarab beetles. Biological control by entomopathogenic fungi has shown to be effective in some cases, however host range is often species-specific. Therefore, in order to effectively use the entomopathogens against scarab beetles, one needs to identify target species in grub-infested area and consequently select strains that are capable of overcoming the host’s defences.

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Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia 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.)

Laboratory bioassays were conducted to evaluate the efficacy of twenty one commonly used insecticides (both conventional and novel group of insecticides) against adult beetles of pleurostrict scarab species, Adoretus simplex, Adoretus versutus, Anomala bengalensis, Anomala dimidiata, Anomala lineatopennis, Holotrichia longipennis, Holotrichia rosettae, Holotrichia seticollis, Maladera similana and Sophrops sp. All the insecticides were evaluated in two tier methodology viz., ingestion toxicity and contact toxicity. Scarab beetle species differed significantly in their response to some of the tested insecticides. Maladera similana was found to be the most susceptible species to all insecticides tested. Among the twenty one insecticides, chlorpyriphos 20% EC @ 2 mL/L, dichlorvos 76% EC @ 1 mL/L, lambdacyhalothrin 5% EC @ 1 mL/L and acephate 75% SP @ 1.6 g/L recorded high mortality, whereas buprofezin 25% SC @ 2 mL/L and neem seed kernel based EC (azadirachtin 0.15%) @ 6 mL/L recorded low mortality of all ten scarab species in leaf dip bioassay. In contact toxicity assay chlorpyriphos 20% EC @ 2 mL/L and dicholorvos 76% EC @ 1 mL/L were found to be most efficient over all other insecticides tested. The study reveals that chlorpyriphos 20% EC @ 2 mL/L and dicholorvos 76% EC @ 1 mL/L can be the best options available for efficient management of white grub beetle outbreaks under field conditions. [ABSTRACT FROM AUTHOR]

Liogenys Guérin‐Méneville is one of the most species rich genera in the Scarabaeidae family endemic to South America. Some species of this genus are important root‐feeding pests of maize, soybean, wheat and oat in their larval stage. Prior to the present study, all known reports of damage caused by any Liogenys species were from Brazil. Since 2006 in Argentina white grubs of the genus Liogenys (not previsouly identified to species level) have been recorded causing a decrease in soybean yields. This research confirms that the Argentinian species is L. suturalis (Blanchard), an important pest already recorded in Brazil but associated with yield losses of maize crops instead of soybean. Taxonomical and biological data observed in Argentinian populations are presented. This is the first record of L. suturalis damaging soybean and its first report in Argentinian crops. [ABSTRACT FROM AUTHOR]

[Display omitted] • Turfgrass has many insect pests which are typically managed preventively with synthetic insecticides. • We studied the potential of fresh field isolate mixes of endemic entomopathogenic nematodes for multi-year suppression of turfgrass insect pests. • Steinernema carpocapsae , Heterorhabditis bacteriophora , and their combination were applied inoculatively to golf course fairways and roughs. • The nematodes persisted throughout most of the 3 years of the study. • The nematodes suppressed white grubs, annual bluegrass weevil, sod webworms, and cutworms throughout the study. Entomopathogenic nematodes (EPNs) can control several important turfgrass insect pests including white grubs, weevils, cutworms, and sod webworms. But most of the research has focused on inundative releases in a biopesticide strategy using EPN strains that may have lost some of their ability to persist effectively over years of lab maintenance and / or selection for virulence and efficient mass-production. Our study examined the potential of fresh field isolate mixes of endemic EPNs to provide multi-year suppression of turfgrass insect pests. In early June 2020, we applied isolate mixes from golf courses of the EPNs Steinernema carpocapsae , Heterorhabditis bacteriophora , and their combination to plots straddling fairway and rough on two golf courses in central New Jersey, USA. Populations of EPNs and insect pests were sampled on the fairway and rough side of the plots from just before EPN application until October 2022. EPN populations increased initially in plots treated with the respective species. Steinernema carpocapsae densities stayed high for most of the experiment. Heterorhabditis bacteriophora densities decreased after 6 months and stabilized at lower levels. Several insect pests were reduced across the entire experimental period. In the fairway, the combination treatment reduced annual bluegrass weevil larvae (59 % reduction) and adults (74 %); S. carpocapsae reduced only adults (42 %). White grubs were reduced by H. bacteriophora (67 %) and the combination (63 %). Black turfgrass ataenius adults were reduced in all EPN treatments (43–62 %) in rough and fairway. Sod webworm larvae were reduced by S. carpocapsae in the fairway (75 %) and the rough (100 %) and by H. bacteriophora in the rough (75 %). Cutworm larvae were reduced in the fairway by S. carpocapsae (88 %) and the combination (75 %). Overall, our observations suggest that inoculative applications of fresh field isolate mixes of endemic EPNs may be a feasible approach to long-term suppression of insect pests in turfgrass but may require periodic reapplications. [ABSTRACT FROM AUTHOR]

ABSTRACT: Plectris alienaChapin, 1934, a white grub that promotes serious damage to a variety of crops in North America and Australia, has been reported for the first time in Brazil. Larvae and adults of P. aliena were recorded in sugarcane crops in the state of Mato Grosso do Sul, sampled by trenches in the soil with light traps, respectively, during 2012 and 2013. Root consumption was also determined for the first, second and third instar larvae. The species is univoltine; adults were found mainly in Aug and the peak of third instar larval density was in Apr in all fields sampled. Pupae and adults of P. aliena were observed in the soil profile at depths of up to 60 and 80 cm, respectively. Larvae of P. aliena of the second and third instar consumed the primary and secondary roots of sugarcane, causing serious damage. Third instar larvae consumed 916 mg of root fresh matter, representing 72 % of the sugarcane root system. These results assist in furthering the understanding of its larval dynamics in the soil and provide support for Integrated Pest Management.

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas 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.)

In this work, we provide morphological illustration and descriptions of the immature stages of the ectoparasitoid robber fly Mallophora ruficauda. Additionally, we studied the ecological aspects of its life cycle through the correlation between the morphology and function performed in each phase of the consumption of their host, the white grub Cyclocephala signaticollis. For the morphological description and quantification of length and width of the egg and larval instars I–II, images were used through optical and scanning electron microscopy. Individuals from larval instars III–V were weighed and measured with digital calibre directly. Finally, images were taken of the cephalic structures of the larval instars and through the use of image processing software we measured in each instar the size of cephalic structures. In addition, the changes in the width of cephalic capsule and the relative size of the maxillary palps and labrum with respect to the width of cephalic capsule were studied for each larval instar through GLMs, to relate the morphology of the cephalic structures with the function they perform. We found that the cephalic structures of the larva undergo changes when moulting to the next instar, according to their relationship with the host, matching with the stage of development where the processes of orientation to the host and attachment to its cuticle take place. These observations reveal, for the first time in a parasitoid asilid larva, the correlation between cephalic morphology and ecological function during the parasitism process and host use. [ABSTRACT FROM AUTHOR]

White grubs are one of the major pests of sugarcane crop in coastal Andhra Pradesh, India. The present study was taken up to assess the efficacy of biocontrol agents viz., entomopathogenic fungi and entomopathogenic nematodes for management of white grub, Holotrichia consanguinea in sugarcane ecosystem during 2015-16 and 2016-17. Two entomopathogenic fungi, Metarhizium anisopliae (NBAIR Ma4 strain) and Beauveria bassiana (NBAIR Bb5a), two entomopathogenic nematodes (Heterorhabditis indica NBAIR-H38 and Steinernema carpocapsae NBAII Sc 05), Neem cake, Phorate 10G were evaluated through soil application as different treatments in white grub infested sugarcane field in coastal Andhra Pradesh for two seasons during 2015 and 2016-17. All biocontrol agent treatments were better than the insecticidal/neem cake application in the management of sugarcane white grubs.However, based on cost benefit ratio of the treatments, soil application of M. anisopliae @ 2.5 kg along with 250 kg farm yard manure per hectare (twice application in July and August) proved superior to other biocontrol agent treatments. Soil application of biocontrol agents, Phorate and Neem cake did not show anydeleterious effect on non-target organisms like, earthworms, earwigs, spiders, coccinellids and chrysopids. [ABSTRACT FROM AUTHOR]

To establish appropriate control index for Holotrichia diomphalia Bates in the context of a continual global warming trend and guidelines based on "Dual Reduction" in chemical fertilizers and pesticides, mortality rates and yield of spring soybean in Northeast China were investigated by artificial inoculation with different density of Holotrichia diomphalia 3rd instar larvae. The results showed that yield had negative correlation with larvae density (y = -0.0135x + 0.4232, 32>x≥1, r = -0.990), yield loss rate had positive correlation with larvae density (y= 3.0051x + 2.6781, x≥1, r=0.991). The yield and yield loss rate were significantly different when larvae density was greater than or equal to 4. According to the rule that the direct benefit was above the cost of control, we determined that the damage of action threshold of H. diomphalia 3rd instar larvae was 2.33 heads per square meter in Northeast spring soybean yield. The mortality rates caused by H. diomphalia 3rd instar larvae were significant different with different population density at different survey periods. The mortality rate ranged from 48.18% to 57.87% at the seedlings stage (V1) when the population density was 1 - 5 heads per square meter, and it ranged from 65.67% to 75.05% until the primary flowering stage (R1). The mortality rate in V1 stage was significantly greater than that in V1 to RI stage. Therefore, the control of grubs would be best performed at seedling stage. [ABSTRACT FROM AUTHOR]

A plant's offspring may escape unfavourable local conditions through seed dispersal. Whether plants use this strategy to escape insect herbivores is not well understood. Here, we explore how different dandelion (Taraxacum officinale agg.) populations, including diploid outcrossers and triploid apomicts, modify seed dispersal in response to root herbivore attack by their main root-feeding natural enemy, the larvae of the common cockchafer Melolontha melolontha. In a manipulative field experiment, root herbivore attack increased seed dispersal potential through a reduction in seed weight in populations that evolved under high root herbivore pressure, but not in populations that evolved under low pressure. This increase in dispersal potential was independent of plant cytotype, but associated with a reduction in germination rate, suggesting that adapted dandelions trade dispersal for establishment upon attack by root herbivores. Analysis of vegetative growth parameters suggested that the increased dispersal capacity was not the result of stress flowering. In summary, these results suggest that root herbivory selects for an induced increase in dispersal ability in response to herbivore attack. Induced seed dispersal may be a strategy that allows adapted plants to escape from herbivores. [ABSTRACT FROM AUTHOR]

White grubs are highly polyphagous and most destructive soil pests inflicting damage to a wide variety of crops. In India, more than 1000 species of white grubs are known of which over 40 species attack wide range of plants. White grubs are naturally infected by various entomopathogens which include fungi, bacteria and nematodes. Entomopathogenic fungi offer great potential and members of genera Beauveria and Metarhizium are widely used against white grubs. Several commercial products of entomopathogenic fungi like Bio Green, ORY-X, Grub X 10G, Betel, Biotrol FMA and Meta-Guard have been developed for the control of white grubs. In India, good control of white grubs in paddy, ginger and sugarcane has been achieved with different entomofungi. Among EPNs, Heterorhabditis bacteriophora is moderately effective against Popillia japonica and Rhizotrogus majalis. H. indica and H. bacteriophora are effective against potato white grubs in India. Paenibacillus popilliae cause milky disease in P. japonica grubs. The bacterium is pathogenic to Holotrichia consanguinea, H. serrata and Leucopholis lepidophora. In north-western Himalaya, B. cereus is highly toxic to the grubs of H. seticollis and Anomala dimidiata. [ABSTRACT FROM AUTHOR]

White grubs (Coleoptera: Scarabaeidae) are polyphagous pests with a wide host range including several commercially important crops. Surveys conducted in different parts of the country covering six states (Assam, Himachal Pradesh, Punjab, Kerala, Karnataka, Uttar Pradesh) during 2015-18 revealed the occurrence of white grubs on major fruit crops like mango, grapes, pomegranate, guava, apple, peach and plum in considerable proportions. Though white grub adults and larvae are known to be pests of fruit crops, they were considered as minor pests. However, the survey results indicate that in the recent past, white grubs are causing considerable damage ranging from 15-40% in different fruit crops and diversity of species occurring also has widened. While young plantations of guava and pomegranate suffered root damage resulting in death of 10-25% plants, other crops were defoliated by adult beetles. White grubs encountered during these surveys mainly belonged to 11 species under six genera viz., Holotrichia, Anomola, Maladera, Schizonycha, Adoretus and Popillia. Emergence of white grubs, once considered to be minor or sporadic pests of fruit crops, necessitates regular surveillance and documentation to implement timely management practices. [ABSTRACT FROM AUTHOR]

Arecanut (Areca catechu) is one of the most important commercial crops in India, which grows extensively in the malnad and coastal areas. White grubs are the most important pests on this crop and cause considerable yield loss. Surveys were conducted to record species that are infested with white grubs of Karnataka and Kerala states. Three species of white grubs were collected and described using morphological and molecular characters. A detailed study of male genitalial structures such as aedeagus and endophallus in three species of Leucopholis Dejean, 1833 (Coleoptera: Scarabaeidae: Melolonthinae) viz. , Leucopholis lepidophora Blanchard, 1850, Leucopholis burmeisteri Brenske, 1894 and Leucopholis coneophora Burmeister, 1855 showed substantial differences. The mitochondrial cytochrome oxidase subunit I gene was sequenced for molecular identification and phylogenetic analysis in this respect. L. lepidophora , L. burmeisteri and L. coneophora species were successfully identified by employing COXI gene. Phylogenetic analyses revealed that the COXI DNA barcode fragment of Leucopholis species and out-group taxa, available in genetic databases, confirms the species identity. Unlabelled Image • The present investigation was based on the molecular identification, morphological characteristics and the structure of male genitals as well. • Three species are reported from Arecanut growing regions of Karnataka, Leucopholis lepidophora Blanchard, L. coneophora Burmeister and L. burmeisteri Brenske. • The genus is characterized by the presence of scales on all parts of the body and a mesosternal spine and a prosternal process. • The described taxa were provided with nucleotide sequences, photographs for key identification characters and male genitalia. [ABSTRACT FROM AUTHOR]

Aphodiinae are a large cosmopolitan subfamily of Scarab beetles (Scarabaeoidea: Scarabaeidae), playing an important role during dung decomposition. Many aspects, especially immature stages, of these dung beetles have not yet been recorded due to their comparative small body sizes and lacking of striking rolling behavior. In this study, the third instar larva of Colobopterus quadratus is morphologically described using scanning electron microscopy. The larva is atypical for the combination of following morphological features: (a) the larval antennae are five‐segmented; (b) the clypeus bears 4 minute protuberances on dorsal surface; (c) the epitorma on epipharynx is ventrally protuberant; (d) the scissorial area of left mandible is broad and blade‐like; (e) the raster is furnished with six glabrous protuberances and two rows of pali arranged in V‐shape. Some significant ultra‐morphological features were discovered in larval Aphodiinae for the first time. The presence of blade‐like incisor on the left mandible implies the potential root cutting ability. [ABSTRACT FROM AUTHOR]

Highlights • Immature morphology of P. dauricus was described using SEM. • The ultra-structure of sound-producing organs on legs was investigated. • Size arrangement and fine structures of the spiracles was present. • The utilization of SEM in the larval morphological study was discussed. Abstract Lucanidae have long received great attention for their adults. However, differentiating between the larvae of stag beetles is difficult and remains unsatisfactorily resolved due to the microscopic features separating groups. In the current study, the larvae of Prismognathus dauricus Motschulsky, 1860 were investigated using light and scanning electron microscopy. The larvae of P. dauricus are atypical for the following characters: i) the epipharynx possesses anteriorly eleven protophoba arranged in a semi-round line; ii) the par stridens consists of 31 ± 0.7 (N = 10) subconical teeth arranged in a slightly curved, longitudinal row; iii) the plectrum is composed of 60 ± 1.4 (N = 10) carinae; iv) the claws of thoracic legs are apically blunt and bear four setae. Moreover, the size arrangement of the larval spiracles also provides valuable taxonomic information. Our SEM study reveals larval ultramorphological characters useful for identification of this species for the first time. [ABSTRACT FROM AUTHOR]

ABSTRACT Third stage larvae and pupae are described based on specimens collected in Mexico: Oaxaca (Cerro Zempoaltepetl), and Chiapas (Amatenango), respectively. Pupal characters are described for the first time for American Hopliinae. Habitus images and figures of diagnostic characters as well as comments on the differences between these larvae and those of Hoplia callipyge LeConte, 1856 and H. equina LeConte, 1880, the only Hopliinae larvae previously known in New World, are also included.

Entomopathogenic nematodes (EPNs) have potential as an alternate means of controlling soil-dwelling pests in settings such as school athletic fields, where use of chemical pesticides is often restricted or prohibited. Athletic fields are also unique among turfgrass systems, as their distinct pattern of foot traffic can result in compaction and other soil properties varying across different areas of the field, potentially causing variability in EPN performance even within a single field, as many abiotic and biotic soil properties are known to influence EPN efficacy. We tested the efficacy of the EPNs Steinernema feltiae and Heterorhabditis bacteriophora against third-instar grubs of the Japanese beetle Popillia japonica in high-traffic and low-traffic areas of two soccer fields in New York State, one grown atop loam soil and the other atop loamy sand. Efficacy was low in the loam soil but modest for both species in the loamy sand, though the only significant increase over controls occurred in S. feltiae -inoculated plots within low traffic areas in 2016. Non-metric multidimensional scaling revealed positive associations between efficacy of both EPN species and soil sand content, suggesting that sandy soils are most optimal for curative applications against turfgrass pests. Soil biotic factors, such as microarthropod abundance, were not found to have an effect on EPNs. These results will aid turfgrass managers by improving knowledge of the conditions required for effective use of EPNs. [ABSTRACT FROM AUTHOR]

White grubs are polyphagous subterranean insect pests which have recently emerged as a major threat to sugarcane cultivation. For effective management of these pests in sugarcane, studies were undertaken to evaluate various locally isolated as well as commercially available microbial biocontrol agents, entomopathogenic nematodes and novel chemical pesticides against white grubs. Attempts were made to isolate effective bio-agents associated with white grubs in indo-gangetic plains of India. Altogether, nine local bacterial isolates associated with infected white grubs were isolated and tested for their bio-efficacy under laboratory condition. However, none of the isolates were found effective against the predominant species, Holotrichia consanguinea. Hence, attempt was made to assess the field efficacy of already available five microbial bio-agents, viz., Metarhizium anisopliae, Beauveria bassiana, Bacillus cereus strain WGPSB-2, Heterorhabditis indica, Steinernema carpocapsae and three insecticides, viz., Chlorantraniliprole 0.4 G, Fipronil + Imidacloprid 80 G and Chlorpyriphos 10 G at their recommended doses. Results of the experiments conducted for 2 years under randomized block design revealed that treatment of Bacillus cereus strain WGPSB-2 @10 kg/ha (1 × 1013 cfu/ha) could reduce the white grub damage to the extent of 59.8%, while other bio-agents could reduce the damage in the range of 24.3-39.5% over untreated control. All the insecticides were found effective in reducing white grub damage, and in most of the observations, difference in reduction in the white grub damage was statistically non-significant. However, Chlorantraniliprole 0.4 G @ 20 kg/ha was most effective, which could reduce the grub damage to the extent of 89.10% over untreated control. [ABSTRACT FROM AUTHOR]

Abstract: Herbivore‐induced defences in plants are considered a strategy to manage multiple interactions while saving resources. The optimal defence theory (ODT) is one of the most prominent theoretical frameworks to explain the defence allocation patterns within plants. It was recently shown that the ODT generally applies to constitutive glucosinolate (GSL) allocation in shoot and root organs. Previous studies showed that both root and shoot herbivore feeding may alter defence allocation over plant organs. For shoots, the effect depends on where the herbivores feed. It is as yet unknown whether similar principles apply to root‐herbivore‐induced GSLs. To analyse the effects of root localized herbivore feeding on GSL allocation, we conducted a pot experiment using Anomala cuprea grubs and four Brassicaceae; Brassica rapa, B. nigra, B. oleracea and Sinapis alba. Individuals of these four plant species were grown in dedicated mesocosms. The grubs were confined either to the bottom soil, the middle section or the topsoil. Plants grown in the same set‐ups but without root herbivores served as controls. Glucosinolate levels of the leaf lamina, petiole and stem as well as of the taproot, lateral roots and fine roots were measured after 8 days of herbivory. Plant biomass reduction due to herbivory was the largest when herbivores were confined to the topsoil. In the three Brassica species, taproot GSL levels increased upon herbivory independent of where the root herbivores were feeding. Glucosinolate levels in fine roots and shoots, on the other hand, hardly responded to root herbivory. Indole GSLs, which are more effective to pathogens than to herbivores, were more strongly induced than aliphatic and aromatic GSLs, especially in the taproots. Sinapis alba did not show remarkable increments in any GSL level upon herbivory. These results show that locally and systemically induced defences in roots are consistent with the ODT: The taproot which is the most vulnerable and valuable to plant performance shows the highest increase in defence induction. The induced GSL profiles suggest that the response may not only target herbivores, but may also help to prevent secondary infection by microbial pathogens. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Whole white grub aqueous fluid is known to protect liver from injury induced by CCl4; whether this is conferred by one or all the two components of the white grub fluid has not been clearly determined. This study was carried out to evaluate the hepatoprotective effects of the methanolic extracts of white grubs (anterior and posterior portions) on liver injury induced by carbon tetrachloride (CCl4) in rat (Rattus norvegicus). The anterior methanolic extract (AME) and posterior methanolic extract (PME) were obtained from the incision of white grub's abdomen and extracted by using methanol. Male albino rats weighing between 150 g-200 g were used. Ten groups of rats (n=6) were administered orally, once in a day for five days with normal saline (negative control), 10 mg/kg of silymarin (positive control) or 50 mg/kg and 100 mg/kg of posterior methanolic extract (PME) and anterior methanolic extract (AME) of white grubs respectively followed by hepatotoxicity induction using CCl4 on day 2 and 3 of the experiment. Blood and liver samples were collected for biochemical and histopathological studies respectively. Rats pretreated with silymarim, PME (50 mg/kg) and AME (100 mg/kg) and normal control groups showed a significant decrease (pd"0.05) in the levels of aspartate amino transferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP). Histopathological study showed intense vacuolation, hepatic necrosis and haemorrhage in CCl4 (negative control), PME (100 mg/kg), AME (50m g/kg) pretreated groups; while normal hepatic structure was observed in groups pretreated with silymarin, PME (50 mg/kg), AME (100 mg/kg) and normal control groups. The study showed that PME (50 mg/kg) and AME (100 mg/kg) have hepatopotective effects against CCl4-induced liver damage. [ABSTRACT FROM AUTHOR]

In this study, the utility of inoculative releases of local strains of Heterorhabditis bacteriophora and Steinernema feltiae isolated from northern New York (NY) State for managing soil-dwelling pests in sod (turfgrass production systems) was evaluated. The objectives of the project were to (a) quantify changes in biocontrol potential during the sod production process and (b) evaluate the potential for the nematodes to suppress populations of soil-dwelling turf pests following harvest and installation at a new site. A field study was conducted on four sod fields in central NY State on soils with varying texture and organic matter content, and a post-harvest sod installation study was performed in the greenhouse on a sandy loam soil. Nematode-induced mortality of Galleria mellonella was increased significantly one month following inoculation but differed between fields with different soil types, likely due to variation in soil organic matter content. In the following year, nematode persistence in sod fields was low, likely driven by moderate to severe drought conditions. In contrast, upon harvest and installation, significant nematode-induced mortality was observed in soil receiving an installation of muck-produced sod. Enhanced nematode-induced mortality was detected in both the greater wax moth and third instar Japanese beetle larvae. This study indicates that inoculation of sod with entomopathogenic nematodes can improve biocontrol potential during sod production and after harvest, however, the utility of this practice is sensitive to soil conditions, and likely most efficacious on coarse-textured soils with high organic matter. [ABSTRACT FROM AUTHOR]

Description of the third instar larvae of five species of Cyclocephala (Coleoptera, Melolonthidae, Dynastinae) from Mexico. Larvae of four species of Cyclocephala are described for the first time based on specimens collected in Mexican localities: C. barrerai Martínez, 1969 from Puebla, C. sinaloae Howden & Endrödi, 1966 from Sinaloa, C. fasciolata Bates, 1888 from Veracruz, and C. jalapensis Casey, 1915 from Hidalgo. Larva of C. lunulata Burmeister, 1847, is redescribed based on specimens from the Mexican states of Morelos, Puebla, and Veracruz. Diagnostic structures are illustrated and the differences and similarities of each species with other previously described larvae of the genus are commented.

Previous research has uncovered that the cuticle of P. polyphylla larvae acts as a good non-immunological barrier against M. pingshaense. In the present study we investigated whether P. polyphylla larvae also show a similarly robust immunological response against M. pingshaense. Firstly, we estimated a median lethal dose (LD50) of blastospores to be injected into the hemocoel. Secondly, we injected the estimated LD50 of blastospores into the hemocoel of larvae to quantify phenoloxidase (PO), nitric oxide (NO) and antimicrobial activity as a response against fungal invasion. In contrast to a previous report that showed that M. pingshaense is unable to kill P. polyphylla after topical applications, here we demonstrate that: (a) 100 % of P. polyphylla larvae died when blastospores were injected into the hemocoel and (b) when injecting the LD50 into the hemocoel of the larvae, immune response did not differ with control. Our results imply that immunological responses do not protect P. polyphylla larvae against M. pingshaense infections. Thus, the cuticle seems a better defense mechanism compared to PO, NO and antimicrobial activity. One proximate explanation for our results is that blastospores are not detected by the host’s immune machinery. An ultimate explanation is that there may be a resource-based tradeoff between non-immunological and immunological barriers, in which white grubs may be investing more in cuticle at the cost of PO, NO and antimicrobial activity.