Beetle Feeding Research Articles

Comparative metagenomic study unveils new insights on bacterial communities in two pine-feeding Ips beetles (Coleoptera: Curculionidae: Scolytinae).

Climate change has recently boosted the severity and frequency of pine bark beetle attacks. The bacterial community associated with these beetles acts as "hidden players," enhancing their ability to infest and thrive on defense-rich pine trees. There is limited understanding of the environmental acquisition of these hidden players and their life stage-specific association with different pine-feeding bark beetles. There is inadequate knowledge on novel bacterial introduction to pine trees after the beetle infestation. Hence, we conducted the first comparative bacterial metabarcoding study revealing the bacterial communities in the pine trees before and after beetle feeding and in different life stages of two dominant pine-feeding bark beetles, namely Ips sexdentatus and Ips acuminatus. We also evaluated the bacterial association between wild and lab-bred beetles to measure the deviation due to inhabiting a controlled environment. Significant differences in bacterial amplicon sequence variance (ASVs) abundance existed among different life stages within and between the pine beetles. However, Pseudomonas, Serratia, Pseudoxanthomonas, Taibaiella, and Acinetobacter served as core bacteria. Interestingly, I. sexdentatus larvae correspond to significantly higher bacterial diversity and community richness and evenness compared to other developmental stages, while I. acuminatus adults displayed higher bacterial richness with no significant variation in the diversity and evenness between the life stages. Both wild and lab-bred I. sexdentatus beetles showed a prevalence of the bacterial family Pseudomonadaceae. In addition, wild I. sexdentatus showed dominance of Yersiniaceae, whereas Erwiniaceae was abundant in lab-bred beetles. Alternatively, Acidobacteriaceae, Corynebacteriaceae, and Microbacteriaceae were highly abundant bacterial families in lab-bred, whereas Chitinophagaceae and Microbacteriaceae were highly abundant in wild I. accuminatus. We validated the relative abundances of selected bacterial taxa estimated by metagenomic sequencing with quantitative PCR. Our study sheds new insights into bacterial associations in pine beetles under the influence of various drivers such as environment, host, and life stages. We documented that lab-breeding considerably influences beetle bacterial community assembly. Furthermore, beetle feeding alters bacteriome at the microhabitat level. Nevertheless, our study revisited pine-feeding bark beetle symbiosis under the influence of different drivers and revealed intriguing insight into bacterial community assembly, facilitating future functional studies.

The Biology, Impact, and Management of Xyleborus Beetles: A Comprehensive Review.

Xyleborus beetles, a diverse group of ambrosia beetles, present challenges to forestry and agriculture due to their damaging burrowing behavior and symbiotic relationships with fungi. This review synthesizes current knowledge on the biology, ecology, and management of Xyleborus. We explore the beetles' life cycle, reproductive strategies, habitat preferences, and feeding habits, emphasizing their ecological and economic impacts. Control and management strategies, including preventive measures, chemical and biological control, and integrated pest management (IPM), are critically evaluated. Recent advances in molecular genetics and behavioral studies offer insights into genetic diversity, population structure, and host selection mechanisms. Despite progress, managing Xyleborus effectively remains challenging. This review identifies future research needs and highlights innovative control methods, such as biopesticides and pheromone-based trapping systems.

Scarabaeolus carniphilus: a necrophagous dung beetle (Coleoptera: Scarabaeinae) buries and feeds on a dead snake

A rare sighting of two male carrion specialist dung beetles, Scarabaeolus carniphilus Deschodt & Davis, 2015, burying a freshly dead Herald snake (Crotaphopeltis hotamboeia (Laurenti, 1768)) is documented from its discovery in the field and subsequent reburial under laboratory conditions. The species studied is a member of the telecoprid (dung roller) Scarabaeini, but behaved here like a paracoprid; it deliberately cut into and removed flesh from the dead snake; these pieces were then taken into a feeding burrow; later a pheromone release stance was taken up near an established burrow; and under laboratory conditions the snake was completely buried. These observations, mostly novel for this species and its genus are clearly documented via photographs and an online time lapse video taken every hour for 24-hours during the snake’s-(re)burial. This note introduces relevant aspects of dung beetle natural history and new biological information for Scarabaeolus and particularly for Sc. carniphilus. It records and interprets a carrion specialist Scarabaeini dung beetle burying and feeding on fresh carrion; highlights natural history findings (pheromone release) previously not considered for the evolution of the Scarabaeini; and aims to stimulate behavioural research into this interesting and under studied genus Scarabaeolus.

Reducing flea-beetle feeding wounds on canola seedlings with foliar insecticide failed to improve blackleg control

In 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.

Alpha and beta‐diversity and community structure of dung beetle assemblages in an East African protected savannah

AbstractFew studies have examined how dung beetle species composition changes across several mammalian dung types. Species composition and abundance of dung beetles were studied in dung samples of seven African mammals along animal trails and using 14 baited‐pitfall traps in both the park and the buffer zone resulting in a combined data set of 113 samples. Both the number of species (18) and the number of individual dung beetles (600) encountered were low for an area close to the Equator. Few species (2) and herbivores (13) tunnellers (9) dominated the dung beetles community, feeding and guild structure respectively. Alpha diversity was moderate 2.06 (1 &lt; H′ ≤ 3). Beta diversity ranged from low 0.8 (high similarity) to high (zero, no similarity). Dung beetle species composition varied with dung type with the degree of pairwise similarity between two dung types in 19 of the total (21) dung beetle communities comparisons showing low similarity (0.4) to no similarity (zero). The observed discrepancies may be attributed to dung size, composition and consistency as well as to the low number of dung of the different animal species sampled. Furthermore, further research is needed as rarefaction curves suggest that sampling was incomplete.

Dung-beetles (Coleoptera, Scarabaeidae, Aphodiinae, Scarabaeinae) feeding on faeces of steppe marmots Marmotabobak (Rodentia, Sciuridae) in Middle Volga territory.

In open terrestrial biomes of Holarctic realm, ground squirrels are recognised as keystone species inhabiting steppes. They shape the plant species composition and diversity and support a fauna of species associated with their burrows. Ground squirrels and associated dung-beetles are important elements of the steppe food webs, yet the trophic associations between species are still poorly studied. The area in the northern outskirts of Obshchy Syrt plateau, on the border of Samara and Orenburg Provinces of Russia was surveyed and scarab beetles (Scarabaeidae) feeding on steppe marmot (Marmotabobak (Müller, 1776)) faeces were collected from six localities. Twenty eight species of two subfamilies - Aphodiinae and Scarabaeinae, - were identified with the majority of species belonging the genus Aphodius Hellwig, 1798. Seven species are recorded as consumers of marmot faeces for the first time. Only two nidicolous specialist species were found which suggests that the studied population of steppe marmots is as result of the recent secondary colonisation and not all the associated scarab beetle faunas were re-established.

Post-Fire Coleoptera Fauna in Central Russian Forests after the 2021 Fires (Study Using Beer Traps).

Fires can significantly impact forest ecosystems. However, studies on the effects of fires on insect communities in post-fire plots in natural forests are rare. This study presents an analysis of the Coleoptera fauna in the forests of the Mordovia State Nature Reserve (European Russia) in 2022 and 2023 after a fire. Insects were sampled from burned plots (9) in 2010 and 2021, as well as unburned (control) plots (2), and alpha diversity was compared. After processing the material, we examined a total of 12,218 Coleoptera specimens from 38 families and identified 194 species. The families Nitidulidae, Cerambycidae, Elateridae, and Scarabaeidae were the most abundant across all plots. Cerambycidae, Elateridae, Nitidulidae, Staphylinidae, Coccinellidae, and Scarabaeidae exhibited the greatest species diversity. In total, 17 species were found on all plots, including Cetonia aurata, Protaetia cuprea volhyniensis, Trogoderma glabrum, Carpophilus hemipterus, Epuraea biguttata, Glischrochilus grandis, Glischrochilus hortensis, Glischrochilus quadripunctatus, Soronia grisea, Pediacus depressus, Chrysanthia geniculata, Anastrangalia reyi, Leptura quadrifasciata, Leptura thoracica, Lepturalia nigripes, Rhagium mordax, and Anisandrus dispar. Only five species exhibited preferences for certain plots. Maximum abundance and species diversity were observed on unburned (control) plots. The plots where fires occurred in 2010 and 2021 had the lowest total abundance values for Coleoptera. These fires destroyed almost all potential sites for beetle settlement, feeding, breeding, and shelter. Traps recorded a higher abundance of Coleoptera in the first year after fires compared to the second year. The Coleoptera fauna showed the greatest similarity on the control plots.

Trait-environment interactions of saproxylic beetles as a guide to biodiversity conservation strategies

Conservation of biodiversity requires in-depth knowledge of trait-environment interactions to understand the influence the environment has on species assemblages. Saproxylic beetles exhibit a wide range of traits and functions in the forest ecosystems. Understanding their responses to surrounding environment thus improves our capacity to identify habitats that should be restored or protected. We investigated potential interactions between ecological traits in saproxylic beetles (feeding guilds and habitat preferences) and environmental variables (deadwood, type and age of surrounding forest). We sampled beetles from 78 plots containing newly created high stumps of Scots pine and Silver birch in boreal forest landscapes in Sweden for three consecutive years. Using a model based approach, our aim was to explore potential interactions between ecological traits and the surrounding environment at close and distant scale (20 m and 500 m radius). We found that broadleaf-preferring beetle species are positively associated with the local broadleaf-originated deadwood and broadleaf-rich forests in the surrounding landscapes. Conifer-preferring species are positively associated with the local amount of coniferous deadwood and young and old forests in the surrounding landscape. Fungivorous and predatory beetles are positively associated with old forests in the surrounding landscapes. Our results indicate that both local amounts of deadwood and types of forests in the landscape are important in shaping saproxylic beetle communities. We particularly highlight the need to increase deadwood amounts of various qualities in the landscape, exempt older forests from production and to increase broadleaf-rich habitats in order to meet different beetle species’ habitat requirements. Trait responses among saproxylic beetles provide insights into the significance of broadleaf forest and dead wood as essential attributes in boreal forest restoration, which helps conservation planning and management in forest landscapes.

The Neurotranscriptome of Monochamus alternatus.

The Japanese pine sawyer Monochamus alternatus serves as the primary vector for pine wilt disease, a devastating pine disease that poses a significant threat to the sustainable development of forestry in the Eurasian region. Currently, trap devices based on informational compounds have played a crucial role in monitoring and controlling the M. alternatus population. However, the specific proteins within M. alternatus involved in recognizing the aforementioned informational compounds remain largely unclear. To elucidate the spatiotemporal distribution of M. alternatus chemosensory-related genes, this study conducted neural transcriptome analyses to investigate gene expression patterns in different body parts during the feeding and mating stages of both male and female beetles. The results revealed that 15 genes in the gustatory receptor (GR) gene family exhibited high expression in the mouthparts, most genes in the odorant binding protein (OBP) gene family exhibited high expression across all body parts, 22 genes in the odorant receptor (OR) gene family exhibited high expression in the antennae, a significant number of genes in the chemosensory protein (CSP) and sensory neuron membrane protein (SNMP) gene families exhibited high expression in both the mouthparts and antennae, and 30 genes in the ionotropic receptors (IR) gene family were expressed in the antennae. Through co-expression analyses, it was observed that 34 genes in the IR gene family were co-expressed across the four developmental stages. The Antenna IR subfamily and IR8a/Ir25a subfamily exhibited relatively high expression levels in the antennae, while the Kainate subfamily, NMDA subfamily, and Divergent subfamily exhibited predominantly high expression in the facial region. MalIR33 is expressed only during the feeding stage of M. alternatus, the MalIR37 gene exhibits specific expression in male beetles, the MalIR34 gene exhibits specific expression during the feeding stage in male beetles, the MalIR8 and MalIR39 genes exhibit specific expression during the feeding stage in female beetles, and MalIR8 is expressed only during two developmental stages in male beetles and during the mating stage in female beetles. The IR gene family exhibits gene-specific expression in different spatiotemporal contexts, laying the foundation for the subsequent selection of functional genes and facilitating the full utilization of host plant volatiles and insect sex pheromones, thereby enabling the development of more efficient attractants.

Neem's promise: The way to a sustainable future and eco-friendly biopesticides

Modern agriculture must include pest management since pests can seriously harm crops and lower yields, resulting in considerable financial losses. Conventional chemical insecticides have been used as the main method of pest management, but their detrimental effects on the environment and human health have inspired the quest for new environmentally friendly options. In this situation, Azadirachta indica showed promise as a sustainable and eco-friendly biopesticide. This research shows many aspects for Azadirachta indica as an environment friendly biopesticide. Neem is well known for having antiviral, antiseptic, and antifungal characteristics, which make it a crucial component in remedies for many illnesses, skin disorders, and mouth care. It is also beneficial to the environment. When added to the soil, its seeds and leaves help increase the fertility of the soil and structure. Additionally, the tree's large root system helps stop soil erosion. Azadirachta indica, is a great asset in the field of pest control and agricultural sustainability due to its repellent and antifeedant qualities. These characteristics are a result of neem's bioactive substances, known as Azadirachtin which has been the subject of in-depth study and use because of its function as a natural repellent and antifeedant Azadirachtin is a potent natural insect growth regulator because it interferes with beetle feeding, molting, and reproduction. Furthermore, the eco-friendliness of azadirachtin and its safety for people and non-target animals highlight its essential function in sustainable pest management techniques, aiding in the advancement of environmentally friendly and healthier agricultural systems. The neem plant is a unique botanical gem that has enormous medicinal, farming, and cultural significance. Its adaptability and environmental friendliness make it an important resource for sustainable agriculture and human well-being. Three commercialized neem-based formulations were tested aphid, Myzus persicae, including Azatrol, Triple Action Neem Oil (70% neem oil), and Pure Neem Oil (100% neem oil) in greenhouse and laboratory settings. A bioassay using a leaf disc choice test indicated that of the established neem-based insecticides tested were effective against the aphid at the recommended concentrations. However, a doubling in the quantity of Azatrol and Triple Action Neem Oil resulted in a 50% decrease in the number of aphids landing on handled leaf tissue compared to untreated leaf tissue.

Indirect effects of low-impact thinning on insect communities in forest floor of coniferous plantations

ABSTRACT To reveal the effects of low-impact thinning of coniferous planted forests on insects’ diversity, we investigated the relationship among cover degree and the number of plant species and the number of insect species in eight functional groups of herbivorous beetles, ants and carabid beetles at 63 sites of Japanese cedar and cypress which were thinned or unthinned and located in the middle of Japan. We found that when low thinning was applied to approximately 30% of the stand density, the number of plant species increased from the following year, and cover degree moderately increased in the years following thinning, although canopy openness did not significantly change. Using structural equation modeling, we found that the number of herbivorous beetle species increased with the cover degree increment of feeding-intended plants (woody-plants and herbs/vines) in the 4–8 years after thinning. The number of species of woody-plant feeding beetles also increased with an increase in the number of herb/vine plant species. For ant species, the number of habitat generalist species increased in the 4–8 years after thinning or with cover degree increment, although no response was observed in woodland specialist and open-habitat specialist species. For carabid beetle species, only the number of large-size species, not including open-habitat specialists, increased with cover degree increment. It was considered that there were moderate, and yet sustainable, positive effects of low-impact thinning on species diversity of forest-floor-inhabiting insects via understory vegetation increment with a lag-time, and no promotion of migration of non-forest-habitat ant and carabid beetle species.

Palearctic flea beetle and pest of hops and Cannabis, Psylliodesattenuata (Coleoptera, Chrysomelidae, Galerucinae), new to North America.

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. 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.

Artificial intelligence analysis of contributive factors in determining blackleg disease severity in canola farmlands

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.

Effects of vector‐borne plant pathogen on the interactions between Diaphorina citri and its natural enemy, Harmonia axyridis

AbstractThe Asian citrus psyllid, Diaphorina citri, is a vector of the bacterial pathogen, Candidatus Liberibacter asiaticus (CLas) that is believed to cause huanglongbing (HLB), also known as citrus greening disease. This phytopathogen can manipulate its vectors directly by modifying behaviour and altering fitness and indirectly by reducing host plant quality, which may affect the predation efficiency of natural enemies. Little is known about how this phytopathogen may affect third tropic level predators. The purpose of this investigation was to determine if the CLas pathogen modifies interactions between D. citri and its predators. We tested whether CLas infection of psyllids indirectly affects fitness of a key predator, the lady beetle Harmonia axyridis. We provided ladybeetles with 10 infected or uninfected adult psyllids in choice bioassays and measured the consumption rate over 24 h. Similarly, 15 infected or uninfected adult psyllids were provided to ladybeetles in no‐choice bioassays and feeding rates and net weight gain of male and female beetles were measured over 5 consecutive days. Fecundity and fertility of lady beetles feeding on CLas‐infected D. citri was reduced compared with those feeding on uninfected D. citri, and oocyte development appeared diminished in those beetles feeding on infected compared with uninfected psyllids. However, in choice assays, beetles did not distinguish between CLas‐infected and uninfected psyllids. We postulate that CLas may reduce the nutritional quality of psyllids diminishing fecundity and fertility of their predatory beetles. Our results lead us to speculate that under conditions of near 100% HLB infection, as occurs endemically in Florida, effectiveness of biological control for D. citri may benefit from provisioning ladybeetle predators with alternative hosts of higher nutritional quality or augmentative releases of laboratory‐reared predators.

Cues of uncommon food habits within dung beetles: Notes from a seasonally dry tropical forest in South America

The assessment of species’ diet and trophic plasticity serve as key elements to understand their adaptations to harsh ecosystems, such as deserts and dry forests. Among dung beetles, coprophagy is the main feeding habit, which may be substituted or complemented by other unusual diets, such as granivory and necrophagy. This study presents new records of dung beetle uncommon diets in Caatinga, the largest Seasonally Dry Tropical Forest in America. We include novel descriptions of the genera Dichotomius Hope, 1838 and Canthidium Erichson, 1847 in using and removing seeds in Caatinga. We also present the first report of dung beetles from Caatinga attracted to dead millipedes, specifically for Coprophanaeus pertyi (Olsufieff, 1924). Also, we found goat hairballs along with the roller beetle Deltochilum verruciferum Felsche, 1911 inside a pitfall trap, suggesting that this species may use animal fur to feed or breed. Finally, we included an updated list on unusual food records of dung beetle species in Caatinga dry forest. Our findings indicate that dung beetles in Caatinga display diverse feeding habits in response to extreme environmental conditions and/or limited resources. We expand the still-scarce knowledge regarding dung beetle feeding ecology outside their interaction with dung or the soft tissues of carrion. Despite our findings, new evidence is essential to reinforce our understanding on trophic plasticity of dung beetles in Caatinga. A better comprehension of resource plasticity by dung beetles will also be a significant input for biodiversity conservation due to the changes in food availability in anthropogenic landscapes.

Status of forest remnants invaded by tradescantia (Tradescantia fluminensis Vell.) following introduction of biocontrol beetles and manual clearance after three years

ABSTRACT We compared biocontrol beetles and manual clearing of tradescantia in forest remnants invaded by tradescantia (Tradescantia fluminensis Vell.) on the agriculturally modified Hikurangi floodplain, northern New Zealand, to inform best practice in enhancing native biodiversity. Four forest remnant study sites were used: two on dairy farms and two protected in a reserve. We assessed tradescantia biomass and cover as indicators of biocontrol effectiveness in the short term, and composition and seedling establishment for effectiveness in the longer term. We found the biocontrol treatment (a combination of tradescantia beetles Neolema ogloblini, Neolema abbreviata, and Lema basicostata) was slow in reducing tradescantia biomass and had little effect in promoting regeneration of native forest species after 3 years. Beetle feeding damage was significantly higher at the biocontrol sites; however, tradescantia biomass or cover was not significantly lower. Although tradescantia biomass in the biocontrol treatment was decreasing, several more years would probably be required for beetle populations to increase and reduce biomass sufficiently to facilitate survival of native seedlings. Results between sites were variable, although dairy farm sites had overall higher nutrient status with higher total potassium levels, and lower nitrogen/phosphorus ratios, and generally higher tradescantia biomass. Manual clearing (‘handclear’) of tradescantia increased vascular species richness but was much more labour intensive and required ongoing management of resprouts. Handclear plots also had lower soil water content than control (means = 36% dry weight, 49% dry weight, respectively), a wider range of daily temperatures, and high species losses (as well as gains). Species losses were probably exacerbated by the greater environmental extremes caused by removal of the tradescantia living mulch, and the incomplete recovery of ground cover vegetation and microclimate suitable for seedling regeneration. Biodiversity benefits are likely to accrue slowly following the introduction of biocontrol agents; longer-term, these should prove more cost-effective than handclear.

Drought impacts African black beetle feeding on perennial ryegrass

interactions between plants, herbivorous insects and fungal Epichloë endophytes. However, water availability fluctuates, a phenomenon intensified by climate change, challenging the success of NewZealand’s pastoral industry. The impacts of climatic changes, such as intensifying drought, on pastoral insect pests have received little attention. In a no-choice bioassay, African black beetle (ABB) were fed semi-synthetic diets containing freeze-dried foliage material from drought-exposed and well-watered perennial ryegrass containing endophyte strains AR37 or NZCT, or with material free of endophyte (Nil). Diet consumption, beetle weight change, fungal alkaloid concentrations, phytohormones, and NRI (nitrogen reflectance index) concentrations were measured and compared. Except for AR37, ABB consumed more diets containing drought-exposed rather than well-watered material, with a 61% increase in Nil and a 50% increase in diets containing NZCT, though these effects were not accompanied by corresponding ABB weight changes. Here, we discuss the implications of these results on ABB damage in New Zealand pastures in the context of increasing drought and illustrate how spatial patterns of ABB damage could change over the next 75 years. Areas that do not currently have high populations of ABB such as Manawatū-Whanganui, Wairarapa and Marlborough will become increasingly vulnerable to damage.

Growing media is the major source of damaging population of Systena frontalis (Coleoptera: Chrysomelidae) in ornamental plant nurseries.

Systena frontalis (F.) (Coleoptera: Chrysomelidae) is a serious pest of ornamental shrubs in containerized ornamental plant nurseries in the central and eastern United States. Adult S. frontalis cause numerous shot holes on foliage, rendering ornamental plants unmarketable. Growing media in plant containers is an overwintering site of S. frontalis, but the extent to which adults emerging from the growing media can damage the plants is unclear. Experiments were conducted on panicled hydrangea (Hydrangea paniculata Siebold) in Georgia, North Carolina, and Virginia nurseries in the spring of 2021 and 2022 to answer this question. The treatments were (i) canopy caged, (ii) whole-plant caged, and (iii) noncaged hydrangea plants. In all 3 states, beetle abundance and feeding damage found on caged (whole plant) and noncaged plants were significantly greater than those on plants where only the canopy was caged. In most sites and years, beetle abundance and feeding damage were not significantly different between the noncaged plants and those where the canopy and containers were caged, suggesting that the majority of S. frontalis emerged from the growing media and the majority of damage suffered by the hydrangea plants were caused by beetles emerging from the containers. Because growing media contributed to a significant proportion of the S. frontalis population in a nursery, treatment targeting larvae in the growing media should be a critical component of a holistic management plan against S. frontalis.

Allelochemical Interactions in the Trophic System «Henosepilachna vigintioctomaculata Motschulsky—Solanum tuberosum Linneus»

Henosepilachna vigintioctomaculata is an intrinsic element in the agroecosystem of potato fields. The issues of relationships in the system "potato ladybird beetle-potato plant" have not yet been studied. To study the effect of potato varieties on the potato ladybird beetle, only hatched and active larvae with a hatching rate close to 100% were selected from a laboratory colony. Larvae of the first summer generation collected in potato fields were used in our study to determine the level of adrenaline in the bodies of insects, fresh potato leaves were used to study the content of glycoalkaloids, the content and activity of proteinase inhibitors. The larvae that fed on plants of varieties Belmonda, Queen Anne, Lilly, Dachny, Kazachok, Yubilyar, and Avgustin demonstrated the highest level of stress while the stress level in those that fed on variety Smak was the lowest. The damage inflicted by potato ladybird beetles on leaves of some studied potato varieties led to a progressive increase in the content of glycoalkaloids already within 24 h after the phytophages had been transferred. In most cases, the content of glycoalkoloids increased by 20% within five days. Potato ladybird beetles feeding on plants of different potato varieties caused a progressive increase in proteinase inhibitors (% of the control). Plants of variety Smak did not show a significant increase in the content of alkaloids in the herbage in response to the damage. A correlation was established between the mortality rate, the activity of proteinase inhibitors, the dynamics of glycoalkaloids, and the level of adrenaline, which could be formulated as follows: the higher the content of glycoalkaloids and the activity of proteinase inhibitors in the tissues of potato plants, the higher the level of stress in the potato ladybird beetles that feed on them.

Influence of artificial diets on biological characteristics and digestive enzymes of Coccinella septempunctata L.

In order to improve the rearing of Coccinella septempunctata L. (Coleoptera: Coccinellidae), nutrients such as shrimp, pollen, honey, and lard were added to the basic artificial diet, and the effects of the artificial diet on biological parameters and digestive enzymes were evaluated. The results show that beetles feeding on the supplemented diet exhibited pupation, emergence, fecundity, and hatching rates that were 102.69%, 125.02%, 162.33%, and 119.90% of those supplied with the basic diet, respectively. The addition of shrimp and pollen to the basal diet improved protease, trypsin, chymotrypsin, and aminopeptidase activity in larvae and female adults. The addition of lard improved lipase activity in female adults, and the addition of honey improved invertase activity in adults of both sexes. This study provides guidance for improving the nutritional benefits of ladybug artificial diets.