Harmonia Axyridis Research Articles

Replenishment of the species composition of the bioresource collection of Entomoacariphages

Aim. Formation of the species composition of the bioresource collection "State Collection of Entomoacariphages and Microorganisms" of the Lazarev Experimental Plant Protection Station – a branch of Federal Scientific Centre for Biological Plant Protection. The collection is based on species identified in local biocenoses as well as those introduced from regions with similar climatic conditions.Material and Methods. Collection and study of the effectiveness of native, invasive, introduced entomophages, the dynamics of their acclimatization and the possibility of their introduction into laboratory culture on the territory of the Black Sea coast of Sochi. Methods of their application in plant protection systems were tested.Results. The ability of Cryptolaemus montrouzieri Muls. to control the number of coccids, including Icerya purchase Maskell, has been experimentally established. Entomophages which are effective and adaptable to reproduction in laboratory conditions were selected: Dicyphus errans Wolff. and Macrolophus nubilis H.S., the aphidophage Harmonia axyridis Pall. and others.Conclusion. As a result of the study, wide polyphages of Dicyphus errans Wolff were found to be presented in the collection of the Lazarev Experimental Plant Protection Station, as well as and Macrolophus nubilis H.S., Cryptolaemus montrouzieri Muls., Leis dimidiata Fabr., Harmonia axyridis Pall., Encarsia partenopea Masi and Lysiphlebus fabarum Marsh. Acariphages are represented by Phytoseiulus persimilis Ath.‐Henr. and Amblyseius cucumeris Ond. The biological efficacy of Encarsia partenopea Masi has been evaluated in relation to Trialeurodes vaporariorum Westw. in the conditions of the protected ground of Sochi at the parasite ratio:host of 1:30; 68.6%, the best result being obtained with releases of 1:10; 79.19%. Research has begun on the development of methods for the laboratory breeding of Chilocorus renipustulatus.

Functional Response and Intraspecific Competition of Three Ladybird Species Feeding on Aphids on Goji Berry Plants in Laboratory and Semi-Field Conditions.

The aphid, Aphis gossypii Glover, is identified as a significant pest that causes severe damage to goji berries in China. To analyze the ladybird consumption of aphids, the functional responses of three ladybird species, Harmonia axyridis, Coccinella septempunctata, and Hippodamia variegata, and intraspecific competition among ladybird individuals were evaluated under laboratory conditions. Moreover, the practical impact of ladybirds on aphid population reduction was investigated in semi-field conditions. We found that all adult ladybirds of the three species exhibited a type II functional response toward aphids. According to Holling's disc equation, H. axyridis exhibited the highest searching efficiency (a = 0.79), while C. septempunctata had the shortest handling time (Th = 5.07 min) among the three ladybird species studied. Additionally, intraspecific competition had a greater impact on H. variegata (m = 0.41) compared to the other two ladybird species. The semi-field study demonstrated that H. axyridis (83.9% reduction) and C. septempunctata (78.7% reduction) exhibited higher efficacy in reducing aphid populations compared to H. variegata (27.3% reduction). This study suggests that H. axyridis and C. septempunctata exhibit potential as effective biological control agents against aphids on goji berry plants and highlights the importance of considering intraspecific competition. However, the results obtained from laboratory and semi-field studies cannot be directly extrapolated to field conditions due to the simplification of these experimental systems. Future field studies are crucial in ensuring the effective implementation of a biological control program.

Fight and rescue or give up and flee? Behavioural responses of different ant species tending the mutualist walnut aphid Panaphis juglandis to native and exotic lady beetles.

Mutualism between ants and honeydew-producing hemipterans is a highly successful evolutionary innovation that attains the status of ecological keystone across many terrestrial ecosystems, involving a multitude of actors through direct or cascading effects. In these relationships, ants often protect their hemipteran partners against their arthropod natural enemies, sometimes interfering with the biological control of pest species. However, the dynamics of these interactions are highly variable based on the specific identity of all the actors involved, and baseline data remain scarce. We performed a field experiment exposing colonies of the walnut aphid Panaphis juglandis attended by five European ant species (Camponotus piceus, Ca. vagus, Crematogaster scutellaris, Dolichoderus quadripunctatus, Lasius emarginatus) to a native and an exotic lady beetle (Adalia bipunctata and Harmonia axyridis), documenting the behavioural interactions between these insects and the performance of ants in the protection of the aphids. Our results reveal a significant behavioural diversity among the ant species involved, with D. quadripunctatus and L. emarginatus being the most aggressive and having the best performance as aphid defenders, and Ca. piceus being least effective and often fleeing away. Cr. scutellaris displayed a rare rescue behaviour attempting to pull away the aphids that the lady beetles grabbed. On the other hand, behavioural responses to A. bipunctata and H. axyridis were similar. Further investigations are needed to understand the eco-ethological implications of these differences, while a better understanding of ant behavioural diversity may help refine biological control strategies.

Mating with dead conspecifics in an invasive ladybird is affected by male sexual fasting and time since the female’s death

High promiscuity and low mating partner choosiness in insects can sometimes result in a deviated mating behaviour such as mating with already dead individuals. In this study we investigated the occurrence of necrophilic behaviour in males of the invasive ladybird Harmonia axyridis using two laboratory experiments. For both no-choice and choice experiments, the probability of mating and mating duration were significantly affected by female status (alive, 1-day, 7-day, or 14-day old carcass) and by male mating status (unmated or mated) which was investigated in the no-choice experiment. The presence of chemical cues produced by an alive female did not affect the probability of a male mating with a dead female. In the no-choice experiment, 14-day old female carcasses were significantly less attractive than alive females, and unmated males tended to mate with females of all statuses with significantly higher probability than mated males. In the choice experiment, males showed a significant preference to mate with alive females when compared to 7-day old carcasses but did not distinguish between alive females and 1-day old carcasses. Mating latency (time to the starting of mating) tended to be longer for 14-day old carcasses in the no-choice experiment and was not affected by female status in the choice experiment. Mating duration was negatively affected by age of female carcasses in the no-choice experiment and only 7-day old carcasses were mated for significantly shorter time than alive females in the choice experiment. Mating behaviour was highly consistent for the no-choice and choice experiments. Despite decreasing probability of mating with 7-day and 14-day old carcasses, we observed a surprisingly high frequency of mating with dead conspecifics in the invasive ladybird Harmonia axyridis, which could have serious consequences for transmission of pathogens and affect male fitness even under natural conditions.

Terpene produced by coexpression of the TPS and P450 genes from Lavandula angustifolia protects plants from herbivore attacks during budding stages

To deter herbivore attacks, plants employ a diverse array of volatile compounds, particularly during the early developmental stages. The highly expressed genes LaTPS7, LaTPS8, and LaCYP71D582 were identified during the budding phases of Lavandula angustifolia. In vitro studies revealed that LaTPS7 generated nine distinct compounds, including camphene, myrcene, and limonene. LaTPS8 enzymatically converted eight volatiles by utilizing geranyl diphosphate and nerolidyl diphosphate as substrates. Overexpression of plastid-localized LaTPS7 in Nicotiana benthamiana resulted in the production of limonene. Furthermore, the endoplasmic reticulum-associated enzyme LaCYP71D582 potentially converted limonene into carveol. In N. benthamiana, LaTPS8 is responsible for the synthesis of α-pinene and sylvestrene. Furthermore, leaves transfected with LaTPS7 and leaves cotransfected with LaTPS7 and LaCYP71D582 exhibited a repellent effect on aphids, with an approximate rate of 70%. In comparison, leaves with an empty vector displayed a repellent rate of approximately 20%. Conversely, tobacco leaves expressing LaTPS7 attracted ladybugs at a rate of 48.33%, while leaves coexpressing LaTPS7 and LaCYP71D582 attracted ladybugs at a slightly higher rate of 58.33%. Subsequent authentic standard tests confirmed that limonene and carveol repel Myzus persicae while attracting Harmonia axyridis. The promoter activity of LaTPS7 and LaCYP71D582 was evaluated in Arabidopsis thaliana using GUS staining, and it was observed that wounding stimulated the expression of LaTPS7. The volatile compounds produced by LaTPS7, LaTPS8, and LaCYP71D582 play a crucial role in plant defence mechanisms. In practical applications, employing biological control measures based on plant-based approaches can promote human and environmental health.

Glyphosate decreases survival, increases fecundity, and alters the microbiome of the natural predator Harmonia axyridis (ladybird beetle)

Glyphosate is a widely-used herbicide that shows toxicity to non-target organisms. The predatory natural enemy Harmonia axyridis may ingest glyphosate present in pollen and aphid prey. The present study characterized the responses of adult H. axyridis to environmentally relevant concentrations of glyphosate (5, 10, and 20 mg/L) for one or five days. There were no obvious effects on adult H. axyridis survival rates or fecundity in response to 5 or 10 mg/L glyphosate. However, exposure to 20 mg/L glyphosate significantly reduced the survival rate and increased fecundity. Analysis of the adult H. axyridis microbiota with 16S rRNA sequencing demonstrated changes in the relative and/or total abundance of specific taxa, including Serratia, Enterobacter, Staphylococcus, and Hafnia-Obesumbacterium. These changes in symbiotic bacterial abundance may have led to changes in survival rates or fecundity of this beetle. This is the first report of herbicide-induced stimulation of fecundity in a non-target predatory natural enemy, reflecting potentially unexpected risks of glyphosate exposure in adult H. axyridis. Although glyphosate resistant crops have been widely planted, the results of this study indicate a need to strengthen glyphosate management to prevent over-use, which could cause glyphosate toxicity and threaten environmental and human health.

Arthropod predator community associated with soybean gall midge, Resseliella maxima (Diptera: Cecidomyiidae), in Minnesotan soybean fields.

The soybean gall midge, Resseliella maxima Gagné (Diptera: Cecidomyiidae), is a pest that injures soybeans in the Midwest United States. Little is known about the natural enemies of R. maxima or the potential for biological control. Therefore, we performed a 2-yr survey in Minnesota to examine the predator community associated with R. maxima infestations. We found that Orius insidiosus (Say) (Heteroptera: Anthocoridae) and Pterostichus melanarius (Illiger) (Coleoptera: Carabidae) were the most common foliar- and ground-foraging predators, respectively. Some of the commonly encountered predator species were tested in laboratory predation experiments. Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) and O. insidiosus represented the foliar-foraging predators tested, and H. axyridis consumed significantly more R. maxima larvae than O. insidiosus. Among the ground-foraging predators, 4 carabids were tested. Poecilus lucublandus (Say) (Coleoptera: Carabidae) and Pt. melanarius consumed significantly more R. maxima larvae than Poecilus chalcites (Say) (Coleoptera: Carabidae) and Bembidion quadrimaculatum oppositum (Say) (Coleoptera: Carabidae). We conclude that Pt. melanarius should receive further attention as a potential biological control agent of R. maxima, due to its high abundance in the soybean fields in this study, temporal overlap with the pest, and high propensity to feed on the pest.

Increased pupal temperature has reversible effects on thermal performance and irreversible effects on immune system and fecundity in adult ladybirds

The environmental conditions an organism encounters during development vary in their lasting impact on adult phenotypes. In the context of ongoing climate change, it is particularly relevant to understand how high developmental temperatures can impact adult traits, and whether these effects persist or diminish during adulthood. Here, we assessed the effects of pupal temperature (17 °C – normal temperature, 26 °C – increased temperature, or 35 °C – heat wave) on adult Harmonia axyridis thermal stress tolerance, immune function, starvation resistance, and fecundity. The temperature during pupation significantly affected all investigated traits in fresh adults. Heat acclimation decreased adult haemocyte concentration, cold tolerance, and total egg production, and had a positive effect on heat tolerance and starvation resistance. The negative effects of heat acclimation on cold tolerance diminished after seven days. In contrast, heat acclimation had a lasting positive effect on adult heat tolerance. Our results provide a broad assessment of the effects of developmental thermal acclimation on H. axyridis adult phenotypes. The relative plasticity of several adult traits after thermal acclimation may be consequential for the future geographic distribution and local performance of various insect species.

Pest Identification Using Deep Learning

Pest infestation is indeed a major problem faced by farmers, and it can lead to significant damage to crops. In order to combat this issue, farmers often use pesticides asa means of pest control. Due to less awareness about pesticide and its quantity; lot of experiments are carried out on crops. The excessive and improper use of pesticides can have serious consequences on the environment, wildlife, plants, and human health. It causes various health disorders such as breathing problem, skin cancer and many more. In order to overcome this problem framers should know which pest is harming the crop so that they can use pesticides made for that pest. Our system focuses on pest attacking and harming grapes. Seven classes of insects like Climbing cutworm, Yellow jacket, Grape flea beetle, Multi colored Asian lady beetle, Leaf hopper, Grape phylloxera , Grape berry moth. The system uses deep learning algorithm for Identification of pests. CNN along with YOLOV3 is used for pest identification. An accuracy of 98% is achieved in pest identification. We have developed web application using Django framework where we get by default IP address. The system is developed in the form of web application where the farmer can upload an image, and the pest isidentified immediately with accuracy. Keywords— Agriculture, CNN, YOLOV3

Sublethal effects of acetamiprid and afidopyropen on Harmonia axyridis: insights from transcriptomics analysis

Evaluating the sublethal effects of insecticide is crucial for protecting and utilizing natural enemies. In this study, we determined the sublethal effects of acetamiprid and afidopyropen on Harmonia axyridis (Pallas) and explored the potential molecular mechanisms underlying these effects through transcriptomics analysis. The results showed that sublethal concentrations of acetamiprid significantly reduced the adult fecundity and longevity of F0H. axyridis and decreased the survival time and survival rate of the F1 generation. Sublethal concentrations of afidopyropen prolonged the developmental time of 4th instar larvae in the F0 generation. Additionally, acetamiprid and afidopyropen treatments significantly decreased the predation of H. axyridis. Furthermore, transcriptome sequencing analysis revealed that several P450 and UGT genes expressed differently when H. axyridis were exposed to sublethal concentrations of acetamiprid and afidopyropen, suggesting that the differential expression of detoxifying genes might be involved in the response and detoxification metabolism of acetamiprid and afidopyropen in H. axyridis. Our findings demonstrate that sublethal concentrations of acetamiprid adversely influences the development and predation of H. axyridis, while afidopyropen has limited effects on H. axyridis. These results are helpful for protecting and utilizing natural enemies and guiding the scientific use of pesticides in the field.

Comigration and interactions between two species of rice planthopper (Laodelphax striatellus and Sogatella furcifera) and natural enemies in eastern Asia.

Natural enemies are important in pest control. However, control by natural enemies is hindered by the migration of rice planthoppers. Therefore, comigration and interactions between Laodelphax striatellus (Fallén) and Sogatella furcifera (Horváth) and five predator species, Chrysoperla sinica Tjeder, Harmonia axyridis (Pallas), Episyrphus balteatus, Syrphus corollae (Fab.) and Chrysopa pallens (Rambur) in eastern Asia were investigated. From 2012 to 2021, the migration patterns of two rice planthoppers and five natural enemy species were monitored by suction trapping on Beihuang Island, Shandong Province, China. Both planthoppers and the five natural enemies regularly comigrated from late April to late October each year. There were significant interannual and seasonal differences in the numbers of two rice planthoppers migrating across this island. Simulated seasonal migration trajectories indicated different source areas for the two rice planthoppers, which mainly originated in northeast, north and east China. The biomass of planthoppers was significantly positively correlated with that of the ladybug H. axyridis in all migration periods, and significant differences in the ratio of rice planthoppers to natural enemies among months. A time-lag effect between seasons was obtained when natural enemies and pests comigrated. Migration was coordinated between rice planthoppers and natural enemies in East Asia. When natural enemies and rice planthoppers comigrated, time lags between seasons were observed. The unique insights into the migration patterns will help to increase understanding of the occurrence of rice planthoppers in eastern Asia and provide an important theoretical basis for regional monitoring and management of rice planthoppers. © 2023 Society of Chemical Industry.

Global patterns of genomic and phenotypic variation in the invasive harlequin ladybird

BackgroundThe harlequin ladybird Harmonia axyridis (Coleoptera: Coccinellidae), native to Asia, has been introduced to other major continents where it has caused serious negative impacts on local biodiversity. Though notable advances to understand its invasion success have been made during the past decade, especially with then newer molecular tools, the conclusions reached remain to be confirmed with more advanced genomic analyses and especially using more samples from larger geographical regions across the native range. Furthermore, although H. axyridis is one of the best studied invasive insect species with respect to life history traits (often comparing invasive and native populations), the traits responsible for its colonization success in non-native areas warrant more research.ResultsOur analyses of genome-wide nuclear population structure indicated that an eastern Chinese population could be the source of all non-native populations and revealed several putatively adaptive candidate genomic loci involved in body color variation, visual perception, and hemolymph synthesis. Our estimates of evolutionary history indicate (1) asymmetric migration with varying population sizes across its native and non-native range, (2) a recent admixture between eastern Chinese and American populations in Europe, (3) signatures of a large progressive, historical bottleneck in the common ancestors of both populations and smaller effective sizes of the non-native population, and (4) the southwest origin and subsequent dispersal routes within its native range in China. In addition, we found that while two mitochondrial haplotypes-Hap1 and Hap2 were dominant in the native range, Hap1 was the only dominant haplotype in the non-native range. Our laboratory observations in both China and USA found statistical yet slight differences between Hap1 and Hap2 in some of life history traits.ConclusionsOur study on H. axyridis provides new insights into its invasion processes into other major continents from its native Asian range, reconstructs a geographic range evolution across its native region China, and tentatively suggests that its invasiveness may differ between mitochondrial haplotypes.

Detecting common coccinellids found in sorghum using deep learning models

Increased global production of sorghum has the potential to meet many of the demands of a growing human population. Developing automation technologies for field scouting is crucial for long-term and low-cost production. Since 2013, sugarcane aphid (SCA) Melanaphis sacchari (Zehntner) has become an important economic pest causing significant yield loss across the sorghum production region in the United States. Adequate management of SCA depends on costly field scouting to determine pest presence and economic threshold levels to spray insecticides. However, with the impact of insecticides on natural enemies, there is an urgent need to develop automated-detection technologies for their conservation. Natural enemies play a crucial role in the management of SCA populations. These insects, primary coccinellids, prey on SCA and help to reduce unnecessary insecticide applications. Although these insects help regulate SCA populations, the detection and classification of these insects is time-consuming and inefficient in lower value crops like sorghum during field scouting. Advanced deep learning software provides a means to perform laborious automatic agricultural tasks, including detection and classification of insects. However, deep learning models for coccinellids in sorghum have not been developed. Therefore, our objective was to develop and train machine learning models to detect coccinellids commonly found in sorghum and classify them according to their genera, species, and subfamily level. We trained a two-stage object detection model, specifically, Faster Region-based Convolutional Neural Network (Faster R-CNN) with the Feature Pyramid Network (FPN) and also one-stage detection models in the YOLO (You Only Look Once) family (YOLOv5 and YOLOv7) to detect and classify seven coccinellids commonly found in sorghum (i.e., Coccinella septempunctata, Coleomegilla maculata, Cycloneda sanguinea, Harmonia axyridis, Hippodamia convergens, Olla v-nigrum, Scymninae). We used images extracted from the iNaturalist project to perform training and evaluation of the Faster R-CNN-FPN and YOLOv5 and YOLOv7 models. iNaturalist is an imagery web server used to publish citizen’s observations of images pertaining to living organisms. Experimental evaluation using standard object detection metrics, such as average precision (AP), AP@0.50, etc., has shown that the YOLOv7 model performs the best on the coccinellid images with an AP@0.50 as high as 97.3, and AP as high as 74.6. Our research contributes automated deep learning software to the area of integrated pest management, making it easier to detect natural enemies in sorghum.

Identification and Expression Profiling of the 5-HT Receptor Gene in Harmonia axyridis.

It has been found that 5-hydroxytryptamine (5-HT) modulates the feeding of some insects, and this phenomenon was found in Harmonia axyridis (Pallas) by our previous study. An understanding of the 5-HT system in this beetle is helpful for utilizing 5-HT to modulate its predation to improve biological control efficiency, especially in greenhouses in winter in north China. This is because 5-HT influences diapause in insects by modulating the synthesis and release of prothoracic hormone (PTTH) and, therefore, influences feeding. To elucidate the molecular basis of the H. axyridis 5-HT system, reverse-transcription polymerase chain reaction (RT-PCR), multiple sequence alignment, and phylogenetic tree construction were used to identify the 5-HT receptor in H. axyridis, and quantitative real-time PCR (qRT-PCR) was used to analyze the expression pattern of these receptor genes in different developmental stages and in the nervous system (brain + ventral nerve cord), digestive tract, pectoral muscles, and gonads of the adult ladybird. The results showed that four 5-HT receptors were identified in H. axyridis, named 5-HT1AHar, 5-HT1BHar, 5-HT2Har, and 5-HT7Har. The four receptors were expressed at high levels in the adult stage, especially in 2-day-old adults, with expression levels of 18.72-fold (male) and 14.21-fold (female) of that in eggs for 5-HT1A, 32.27-fold (male) and 83.58-fold (female) of that in eggs for 5-HT1B, 36.82-fold (male) and 119.35-fold (female) of that in eggs for 5-HT2, and 165.47-fold (male) and 115.59-fold (female) of that in eggs for 5-HT7. The level of expression decreased with the advance of day-age in adults. The levels of expression of 5-HT1BHar, 5-HT2Har, and 5-HT7Har were low at the egg, larval, and pupal stages, and 5-HT1AHar was not expressed in the larval stage. The four receptors were expressed in the nervous system, digestive tract, pectoral muscles, and male and female gonads. The 5-HT1AHar was expressed at a high level in the pectoral muscle (6.75-fold of that in the nervous system), 5-HT1BHar in male gonads (1.02-fold of that in the nervous system) and the nervous system, 5-HT2Har in male gonads (5.74-fold of that in the nervous system), and 5-HT7Har in the digestive tract (1.81-fold of that in the nervous system). The results of this study will lay a foundation for research on the function of the 5-HT receptor by RNA interference in the regulation of predation by H. axyridis.

Effects of Fluctuating Thermal Regimes and Pesticides on Egg Hatching of a Natural Enemy Harmonia axyridis (Coleoptera Coccinellidae)

The harlequin ladybird, Harmonia axyridis, is a valuable asset in integrated pest management (IPM); however, issues related to low-temperature storage and transportation have resulted in low hatching rate, while the use of pesticides may lead to non-target effects against this natural enemy during field application. Fluctuating thermal regimes (FTR) have been shown to be beneficial during the low-temperature storage, and the type and concentration of insecticides used are crucial for field application of H. axyridis. Despite this, little research has been conducted on the effects of FTR on the hatching rate of ladybird eggs, and the impact of pesticides on their egg viability remains unclear. To address these gaps, we investigated the effects of different thermal temperatures, recovery frequencies (the number of changes in temperature conditions per unit time), and recovery durations (the duration of the treated temperature condition) on egg hatching under constant low-temperature conditions. We also examined the toxicity and safety of seven commonly used insecticides on egg hatching. Our results indicate that the temperature during FTR application did not significantly affect egg hatching, but the interaction between temperature and recovery frequency can significantly affect egg hatching. Moreover, the recovery frequency and recovery duration had a significant impact on hatching. Under specific conditions, the hatching rate of eggs subjected to FTR was similar to that of eggs stored at 25 °C. Furthermore, we found that matrine (a kind of alkaloid pesticide isolated from Sophora flavescens) had low toxicity to ladybird eggs and is a safe pesticide for use in conjunction with this natural enemy. The study provides valuable information on effectively managing H. axyridis by taking into account both storage temperature and pesticide exposure.

Larval and/or Adult Exposure to Intraguild Predator Harmonia axyridis Alters Reproductive Allocation Decisions and Offspring Growth in Menochilus sexmaculatus

Maternal effects can reduce offspring susceptibility to predators by altering resource allocation to young and reproducing larger offspring. While the perception of predation risk can vary according to a prey’s life stage, it is unclear whether maternally experienced intraguild predation (IGP) risk during different life stages influences the maternal effects of predatory insects. We investigated the influence of exposure to intraguild predators (Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)) during the larval and/or adult stages on reproductive decisions and offspring growth in Menochilus sexmaculatus (Fabricius). Independent of the life stage, when M. sexmaculatus females experienced IGP risk, their body weight and fecundity decreased, but the proportion of trophic eggs produced increased. However, egg mass, egg clutch number, and egg clutch size were not influenced by the treatment. Next, when offspring encountered H. axyridis, mothers experiencing IGP risk during the larval and/or adult stages could increase their offspring’s weight. Moreover, offspring in IGP environments reached a similar size as those with no-IGP environments when mothers experienced IGP risk during the larval and/or adult stages. Overall, M. sexmaculatus larval and/or adult exposure to IGP risk had no influence on egg size, but increased offspring body size when faced with H. axyridis. Additionally, mothers experiencing IGP risk during different life stages showed increased production of trophic eggs. Because IGP is frequently observed on M. sexmaculatus and favours relatively larger individuals, different stages of M. sexmaculatus express threat-sensitively to IGP risk; inducing maternal effects can be an adaptive survival strategy to defend against H. axyridis.

Smelling danger: Lady beetle odors affect aphid population abundance and feeding, but not movement between plants

Predator-prey interactions are complex ecological interactions that influence community structure and function. Predators affect prey density directly by consuming and removing prey from the environment. Additionally, predators can elicit non-consumptive effects in prey which influence prey survival by altering prey behavior and physiology. Key to understanding the consequences of non-consumptive effects for prey populations is determining mechanisms of detection of predation risk. With insects, olfactory cues are commonly used to convey information. It has been shown that insect prey may eavesdrop on predator odor cues as a means to determine predation risk. Herein, we assessed whether the volatile odors of the predatory insect Harmonia axyridis (multicolored Asian lady beetle) affect the behavior (feeding and dispersal behaviors) and performance (population abundance) of aphids (Myzus persicae). Aphids reduced phloem ingestion when feeding in close proximity to lady beetle cues, however, predator odors did not drive aphids to relocate on plants or to disperse across plants away from the odor source. The lack of dispersal we observed is in contrast to studies that show increased aphid movement in the presence of predators that can make physical contact with the aphids. We also found that lady beetle odor cues had a population-level effect on aphids, with 25% reduction in aphid population abundance in the presence of the odor cues. This study highlights that anti-predator strategies may differ depending on the mechanism of detection of predation risk (i.e. olfactory versus physical stimuli), or the context in which they experience them, and raises the question of whether anti-predator responses observed are maladaptive or beneficial to aphid survival. These conclusions are critical for both our basic understanding of the mechanisms driving predator-prey interactions as well as providing insight into pest-natural enemy interactions within agricultural landscapes.

Modern Characterization of Some Novel Compmplexes By Pyrazine as Ligand

Pyrazine is less basic than pyridine, pyridazine and pyrimidine. Derivatives such as Phenazine are well known for their antitumor, antibiotic and diuretic activities. Tetramethyl pyrazine, also known as ligustrazine, is reported to scavenge superoxide anion and decrease nitric oxide production in human polymorphonuclear leukocytes and is a component of some herbs in traditional Chinese medicine. Alkylpyrazines are chemical compounds based on pyrazine with different substitution patterns. Some alkylpyrazines are naturally occurring highly aromatic substances which often have a very low odour threshold and contribute to the taste and aroma of various foods including coffee and wines. Alkylpyrazines are also formed during the cooking of some foods via Maillard reactions. 2,3-Dimethylpyrazine is a component of the aroma of roasted sesame seeds. Dimethylpyrazine is used as flavour additive and adorant in foods such as cereals and products such as cigarettes. It occurs naturally in asparagus, black or green tea, crisp bread, malt, raw shrimp, soya, Swiss cheeses, and wheat bread. Methoxy pyrazines are a class of chemical compounds that produce odours. The odours tend to be undesirable as in the case of certain wines, or as in the case of the Asian lady beetle which produces isopropyl methoxy pyrazine. They have also been identified as additive in cigarettes.

EXPANSION OF <i>HARMONIA AXYRIDIS</i> (PALLAS, 1773) (COLEOPTERA: COCCINELLIDAE) IN THE EUROPEAN PART OF RUSSIA IS CONTINUING

In the European part of Russia, the first records of multicoloured Asian ladybird Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) were observed in 2004 from the territory of the Belgorod Region. In recent years (2018-2020) H. axyridis has quickly spread across the Volga Region and the center of European Russia, and this expansion is continuing. In 2021-2022 H. axyridis was recorded in Saint-Petersburg, Leningrad, Sverdlovsk, Vologda Regions and Mari El Republic for the first time. The findings of H. axyridis from Ekaterinburg are the first record for Trans-Urals territory and the easternmost locality known in invasive (European) part of the species range.

Far-reaching benefits of the consumption of conspecific eggs by neonate larvae of Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae): a case study on an artificial diet

BackgroundThe consumption of conspecific eggs by neonate larvae is a common behavior in aphidophagous coccinellids. However, it is still unknown what far-reaching benefits can be brought to the artificial diet-reared cannibals and whether the age of eggs and/or ovipositing parents can affect the cannibals’ fitness. Here, the multicolored Asian ladybird beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) was used as a research model because it exhibits much stronger cannibalism behavior than other beetles. Nine types of eggs, varying according to parental age at oviposition and egg age per se, were respectively provided as foods for H. axyridis neonate larvae until they developed to 2nd instar. After that, the larvae were fed on an artificial diet and whether egg consumption by neonate larvae had far-reaching benefits was evaluated. Those larvae that directly fed on artificial diet since hatching were served as control.ResultsCompared with the control beetles, the cannibal beetles (with few exceptions) had significantly higher 2nd instar-adult survivals (61.1–75.7% vs. 34.3%) and greatly shortened 2nd instar-adult duration (22.7–24.6 days vs. 27.8 days). At adult emergence, the female cannibal beetles (with few exceptions) had significantly higher fresh weights than the control beetles (14.5–16.3 mg vs. 11.7 mg). Among the nine types of cannibals, non-significant difference was detected in almost all the measured developmental parameters.ConclusionConsumption of conspecific eggs by neonate larvae of H. axyridis had far-reaching benefits for their subsequent development on artificial diet, and neither the egg age nor parental age at oviposition affects the cannibals’ fitness. These findings provided new insights into the combined application of conspecific eggs and artificial diets in the mass rearing of coccinellids.