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Background : Dietary shifts are major evolutionary steps that shape ecological niches and biodiversity. The beetle family Coccinellidae, commonly known as ladybirds, first transitioned from a fungivorous to an insectivorous and subsequently a plant diet. However, the molecular basis of this dietary diversification remained unexplored. Results: We investigated the molecular evolution of dietary shifts in ladybirds, focusing on the transitions from fungivory to carnivory (Coccinellidae) and from carnivory to herbivory (Epilachnini), by comparing 25 genomes and 62 transcriptomes of beetles. Our analysis shows that chemosensory gene families have undergone significant expansions at both nodes of diet change and were differentially expressed in feeding experiments, suggesting that they may be related to foraging. We found expansions of digestive and detoxifying gene families and losses of chitin-related digestive genes in the herbivorous ladybirds, and absence of most plant cell wall-degrading enzymes in the ladybirds dating from the transition to carnivory, likely indicating the effect of different digestion requirements on the gene repertoire. Immunity effector genes tend to emerge or have specific amino acid sequence compositions in carnivorous ladybirds and are downregulated under suboptimal dietary treatments, suggesting a potential function of these genes related to microbial symbionts in the sternorrhynchan prey. Conclusions: Our study provides a comprehensive comparative genomic analysis to address evolution of chemosensory, digestive, detoxifying, and immune genes associated with dietary shifts in ladybirds. Ladybirds can be considered a ubiquitous example of dietary shifts in insects, and thus a promising model system for evolutionary and applied biology. [ABSTRACT FROM AUTHOR]

The ladybird beetle Micraspis discolor plays an important role as a predator of various arthropods within Asia's rice ecosystems. While pollen could serve as an alternative diet for this beetle, facilitating mass-rearing, its pollinivory might inadvertently result in attacks on crop pollen. This study aims to explore the role of gut bacteria on pollinivory of M. discolor. We found that antibiotic treatment significantly reduced the performance of M. discolor when fed Brassica campestris pollen. However, the treatment did not significantly affect their performance when fed an alternative diet of Ephestia kuehniella eggs. Further, we found that antibiotics can eliminate a strain of Serratia marcescens , SmMd, which is a specific gut bacterium in M. discolor. Moreover, the performance of M. discolor showed some degree of recovery when SmMd was reintroduced into its diet. Therefore, we propose that gut bacteria, particularly SmMd, play a significant role in pollen use by this ladybird beetle. This insight enhances our understanding of the important role of gut bacteria in insect adaptation to diverse diets and can potentially optimize the utilization of M. discolor in biological control strategies. [ABSTRACT FROM AUTHOR]

The investigation on population dynamics of sucking pests, their natural enemies, and the per cent disease incidence (PDI) of mung bean yellow mosaic disease (YMD) on Vigna radiata was conducted. During the harvest of the crop, the population of Aphis craccivora, Empoasca kerri, ladybird beetle, and the PDI of YMD was the highest on the 17th Standard meteorolo gical week (SMW). In contrast, the population of Bemisia tabaci was at its peak on the 15th SMW. The minimum temperature had highly significant positive correlation with the population of A. craccivora, E. kerri, B. tabaci, ladybird beetle, and the PDI of YMD. Moreover, there was a significant positive correlation between wind velocity and the population of ladybird beetles. Furthermore, a significant positive correlation was found between the PDI of YMD and the population of B. tabaci. © 2024 Association for Advancement of Entomology. [ABSTRACT FROM AUTHOR]

Eukaryotic genomes exhibit a dynamic interplay between single-copy sequences and repetitive DNA elements, with satellite DNA (satDNA) representing a substantial portion, mainly situated at telomeric and centromeric chromosomal regions. We utilized Illumina next-generation sequencing data from Adalia bipunctata to investigate its satellitome. Cytogenetic mapping via fluorescence in situ hybridization was performed for the most abundant satDNA families. In silico localization of satDNAs was carried out using the CHRISMAPP (Chromosome In Silico Mapping) pipeline on the high-fidelity chromosome-level assembly already available for this species, enabling a meticulous characterization and localization of multiple satDNA families. Additionally, we analyzed the conservation of the satellitome at an interspecific scale. Specifically, we employed the CHRISMAPP pipeline to map the satDNAs of A. bipunctata onto the genome of Adalia decempunctata, which has also been sequenced and assembled at the chromosome level. This analysis, along with the creation of a synteny map between the two species, suggests a rapid turnover of centromeric satDNA between these species and the potential occurrence of chromosomal rearrangements, despite the considerable conservation of their satellitomes. Specific satDNA families in the sex chromosomes of both species suggest a role in sex chromosome differentiation. Our interspecific comparative study can provide a significant advance in the understanding of the repeat genome organization and evolution in beetles. [ABSTRACT FROM AUTHOR]

Ladybird beetles like many other organisms show developmental rate polymorphism in response to various abiotic and biotic factors. Since mating disruption acts as a stressor, we decided to study its impact on the occurrence of developmental rate polymorphs in ladybird beetle, Propylea dissecta Mulsant, 1850 (Coleoptera: Coccinellidae). Ten-day-old females were subjected to mating disruptions at 120, 180 min, and complete mating (211 ± 8.1 min) and then provided with optimum diet of Aphis craccivora Koch. Larvae in each treatment were reared individually and newly emerged adults were assessed on the basis of their developmental durations. They were separated into two lines: slow and fast developers. Extended mating duration was found to be correlated to increased immature survival and reduced offspring development times. Also, in complete mating treatment, percentage of fast developers were more in numbers; thus, mating duration increased the availability of sperm for females and seminal fluid may have boosted maternal protein reserves, which can then be used to produce offspring of better quality. Mating disruption might be a factor reducing the chances of fertilization success and offspring development in P. dissecta. [ABSTRACT FROM AUTHOR]

The ladybird beetle Micraspis discolor plays an important role as a predator of various arthropods within Asia’s rice ecosystems. While pollen could serve as an alternative diet for this beetle, facilitating mass-rearing, its pollinivory might inadvertently result in attacks on crop pollen. This study aims to explore the role of gut bacteria on pollinivory of M. discolor. We found that antibiotic treatment significantly reduced the performance of M. discolor when fed Brassica campestris pollen. However, the treatment did not significantly affect their performance when fed an alternative diet of Ephestia kuehniella eggs. Further, we found that antibiotics can eliminate a strain of Serratia marcescens, SmMd, which is a specific gut bacterium in M. discolor. Moreover, the performance of M. discolor showed some degree of recovery when SmMd was reintroduced into its diet. Therefore, we propose that gut bacteria, particularly SmMd, play a significant role in pollen use by this ladybird beetle. This insight enhances our understanding of the important role of gut bacteria in insect adaptation to diverse diets and can potentially optimize the utilization of M. discolor in biological control strategies.

The experiment was conducted to study the population dynamics of mustard aphid (Lipaphis erysimi Kalt.) and ladybird beetle (Coccinella septempunctata L.) and their correlations with weather parameters. The first incidence of aphid on mustard was observed at the 49th standard meteorological week (SMW) of 2019 and attained its peak at the 5th SMW of 2020. Whereas, the bio-agent of mustard aphid i.e., ladybird beetle population was observed on the 51st SMW (2019) and reached its peak population on the 5th SMW of 2020. A negative correlation of the aphid population was observed with all the environmental factors like temperature, relative humidity and rainfall. And ladybird beetle showed a negative correlation with minimum temperature, relative humidity, and rainfall but with maximum temperature, it showed a positive correlation. [ABSTRACT FROM AUTHOR]

Investigations were carried out on the effect of seed dressing chemicals on the beneficial predators in the Bt cotton ecosystem during 2021-22. All seed dressing insecticides were found safer to the natural enemies as the population of Chrysoperla and ladybird beetle were found comparable to population of untreated control treatment up to 37 days of seed treatment. Similarly, the spider population was also not affected up to 17 days of seed treatment. Thereafter, the population of natural enemies was found higher with the higher prey (sucking pests) populations in the untreated check compared to treatments of seed dressing chemicals and in later treatments, there was no significant difference. The maximum population of spiders (0.52/plant), Chrysoperla (0.42/plant) and ladybird beetle (0.42/plant) was observed in the untreated control. Yield data indicated that the treatment with imidacloprid 70 WG @ 3 g kg-1 obtained highest seed cotton yield (21.69 q ha-1) and it was found superior over the other seed treatments. [ABSTRACT FROM AUTHOR]

Abstract Background The life history and predation rate of the ladybird beetle, Harmonia dimidiata Fabricius (Coleoptera: Coccinellidae) were compared at four different temperatures (16, 20, 24, and 28 °C). The beetles were fed on the bird cherry-oat aphid, Rhopalosiphum padi Linnaeus (Hemiptera: Aphididae) and investigated at 70 ± 10% RH with a photoperiod of 14:10 h (L:D). Results The reproductive rates (R 0) were 20.07, 51.37, 66.95, and 14.54 beetle offspring at 16, 20, 24, and 28 °C, respectively. Results indicated that temperature had good impacts on the feeding potential, development, survivorship and fecundity, especially at 24 and 28 C compared with the other tested temperatures. In addition, the jackknife and bootstrap techniques were employed to estimate the population parameters' means. The obtained means of R 0 and other population parameters, using the bootstrap technique fit a normal distribution. Meanwhile, the jackknife technique generated biologically meaningless zero values for R 0. Both finite and predation rates were incorporated into limited predation rates for comparison of predation potential. Conclusion Both of the growth and predation rates indicated that H. dimidiata is more effective biocontrol agent for R. padi at 24 and 28 °C than at 20, 16 °C.

The current study on population trends of wheat aphid, Rhopalosiphum padi (L.) and its associated natural enemies on different wheat cultivars was carried out at Agriculture Research Institute (ARI) Tarnab, Peshawar Khyber Pakhtunkhwa (KP)-Pakistan during rabi season 2018-2019. Fourteen wheat cultivars i.e Wadaan-17, Paseene-17, Khaista-17, Ghaneemat, KT-2017, Pakhtunkhaw-15, PS-15, NIFA-Insaf-15, NIFAAman-15, Pakistan-13, PS-13, Shahkaar-13, PS-5, NIFA-lalma were planted in Randomized Complete Block design (RCBD) having three (3) replications. Data regarding the population trends of R. padi and its associated natural enemies were recorded on weekly basis. The result showed significant differences among different wheat cultivars with respect to the time interval for most of the parameters. Aphid's population was at its peak during the 3rd week of February but later on, the aphid's population decreased as the population of its natural enemies increased. Based on mean populations of aphid leaf-1, cultivar Pakhtunkhwa-15 recorded the maximum mean number of aphids (5.48 leaf-1), while PS-13 recorded the minimum mean number of aphids (4.09) leaf-1. Data regarding the natural enemies showed that Khaista-17 had a maximum population of Ladybird beetle adults (1.00 plant-1), and Paseene-17 had a maximum population of syrphid fly larvae (0.84 plant-1), and Pukhtunkhwa-15 had maximum lacewings larvae (0.81 plant-1). Overall results revealed that PS-13 showed relatively greater resistance to aphid population with maximum wheat yield (3412.5 kg ha-1) as compared to other wheat cultivars. [ABSTRACT FROM AUTHOR]

Insecticides are the most economic and quick tool to control harmful agricultural insect pests which reduce crop productivity. However, these insecticides have a suppressive and negative impact on non-targeted beneficial fauna. The efficiency and mode of action of numerous insecticides are also much diverse. Therefore, we studied the sublethal impact of bifenthrin (pyrethroids) and clothianidin (neonicotinoids) on ladybird beetle Coccinella septempunctata L. (Coleoptera: Coccinellidae), taking these insecticides as the model representative for the insecticide groups. Our results revealed that both insecticides enhanced the life length of male and female adults of ladybird beetle as compared to control treatment. Bifenthrin reduced the survival rate of larvae and adults as compared to clothianidin and control as well as lowered the fecundity rate of C. septempunctata. After control treatment, the developmental period of each larval instar was shorter in clothianidin than bifenthrin. Adult emergence was also less in clothianidin than in the control group. However, clothianidin triggered the fecundity of the female ladybird beetle. Higher fecundity was recorded in clothianidin treatment as compared to bifenthrin and control which means clothianidin is a better option in integrated pest management (IPM) program as compared to bifenthrin involving the ladybird beetle as a natural biocontrol agent. [ABSTRACT FROM AUTHOR]

Ladybird beetle (Coccinella septempunctata) is present in various crops like cotton, sunflower, fruit plants, and vegetables. C. septempunctata is the free living predatory specie of sucking insect pests such as aphids, mealybugs, and whiteflies and consume many preys during its lifetime. C. septempunctata larvae and adults are both active predators. The present study regarding toxicity of new chemistry insecticides against C. septempunctata was conducted under laboratory conditions. The toxic potential of six synthetic insecticides Emamectin benzoate (200ml/acre), Indoxacarb (175ml/acre), Lufenuron (200ml/acre), Spinetoram (80ml/acre), Chlorantraniliprole (50ml/acre), and Flubendiamide (50ml/acre) were tested on C. septempuctata. The leaf dip bioassay method was performed by collecting sunflower leaves and a 2cm leaf disc with larvae was dipped in insecticides. Data regarding mortality was recorded after 24, 48, 72, 96, and 120 hours. Mortality rates were as follows: 28% for emamectin benzoate, 26% for indoxacarb, 22% for lufenuron, 22% for Spinetoram, 16% for chlorantraniliprole, 14% for chlorantraniliprole, and 10% for Flubendiamide. However, Lufenuron, Spinetoram, and Chlorantraniliprole exhibited moderate toxicity, Indoxacrab and Emamectin benzoate showed severe toxicity, and Flubendiamide showed low toxicity. Our findings offer insights for integrating chemical and biological control strategies to manage sucking insect pests comprehensively. [ABSTRACT FROM AUTHOR]

The ladybird beetle Serangium japonicum is an important predator of whiteflies. Investigations of the molecular mechanisms of this predatory beetle have been hindered by the scarcity of gene sequence data. To obtain gene sequences for the ladybird beetle and determine differences in gene expression between the summer and winter seasons, paired-end sequencing was performed. Real-time PCR was used to validate differences in Krueppel homolog 1 gene (Kr-h1) mRNA expression in summer vs. winter samples. To determined the diversity of the population, annotated cytochrome c oxidase subunit I gene (COX1) gene fragments were amplified from several ladybird beetle populations. The analysis yielded 191,246 assembled unigenes, 127,016 of which (66.4%) were annotated. These functional annotations of gene sequences are currently available from the National Center for Biotechnology Information (NCBI), and will provide a basis for studying the molecular mechanisms underlying the biological characteristics of S. japonicum. We found a change in expression of ribosome-associated genes across seasons, and postulate that this change is because of seasonal variation in temperature and photoperiod. The differential expression of Kr-h1 suggests that S. japonicum can successfully overwinter because the adults enter diapause. To explain the effects of season on Kr-h1 gene expression, we hypothesize a model in which that a short photoperiod affects the density of Ca2+, the subsequent activity of methyl farnesoate epoxidase and the synthesis of JH, and in turn Kr-h1 gene expression. COX1 annotation was concordant with the morphological ID. The same COX1 sequence was found in the samples from several provinces in China. Therefore, the COX1 sequence is worth further study to distinguish beetle species and populations.

The predatory potential of Cryptolaemus montrouzieri Mulsant on mealybugs and aphids viz, Maconellicoccus hirsutus, Phenacoccus solenopsis and Aphis gossypii was studied at the Biocontrol Agents Laboratory, Department of Agricultural Entomology, College of Agriculture, Latur at the temperature of 25±2°C maintained in BOD incubator during year 2013-14. The consumption rate of grubs and beetles of C. montrouzieri was in order of A. gossypii>M. hirsutus>P. solenopsis. [ABSTRACT FROM AUTHOR]

We report here a new species belonging to Nephus (Nephus) Mulsant. Nephus (Nephus) apolonia sp. nov. was collected in the Reunion Island (Mascarene Archipelago, Indian Ocean). We describe this new species and redescribe and illustrate three other Nephus species already known from Reunion: Nephus (Nephus) oblongosignatus Mulsant, 1850, Nephus (Geminosipho) reunioni (Fürsch, 1974) and Nephus (Nephus) voeltzkowi Weise, 1910. Furthermore, we present a phylogenetic tree for these four species and calculate the genetic distances between them, using high-throughput DNA sequencing of the mitochondrial genome. The similar external morphology of N. apolonia sp. nov. and N. voeltzkowi very probably explains why individuals from the first species have been mistakenly identified as the latter and were not recognized as different until now. Other than external and genitalia traits, the present study provides molecular evidence confirming these are indeed two different species. [ABSTRACT FROM AUTHOR]

Satellite DNAs are the major repetitive DNA components in eukaryotic genomes. Although satellite DNA has long been called "parasite DNA" there is substantial evidence that it could be associated with some functions of chromosome biology. Ladybird beetles (Coccinellidae) are one of the largest and most important groups of beetles. Many ladybirds are of economic interest as biological control agents because they eat some agricultural pests such as aphids and scale insects. However, other species are phytophagous and can damage crops. Despite the ecological importance of the latter group there are no studies on their satellite DNA. A satellite DNA family was isolated and characterized in the ladybird Henosepilachna argus. This satellite DNA is organized in tandem repeats of 658 bp and is A + T rich (67.3%). The recorded high sequence conservation of the monomers together with the detection of putative gene conversion processes indicate concerted evolution. Reverse transcription polymerase chain reaction (RT-PCR) revealed that this satellite DNA is transcribed and in situ hybridization its location in the subtelomeric regions of all chromosomes except the long arm of the X chromosome. The presence of this satellite DNA in other species of the genus Henosepilachna and Epilachna was also tested using PCR. The results indicate that this satellite DNA sequence is so far specific to H. argus.

Differences in the time of occurrence of both sexes of adult ladybirds, which reflect differences in the longevity and reproductive strategies of the sexes, is important from the perspective of applied entomology, including biological control, as well as basic entomology. Nevertheless, there is little field census data on this topic. We investigated the seasonal occurrence of both sexes of Cheilomenes sexmaculata (Fabricius) in Osaka City, central Japan, from 2003 to 2011. Female adults tended to appear earlier than males after hibernation or aestivation. That males never appeared earlier than females during the nine year period of this study indicate that protogyny occurs after hibernation and aestivation in this species.

Contamination of environment with heavy metals is increasingly becoming an issue of major concern across the globe. Heavy metals are highly toxic to humans as well as other organisms of the ecosystem. The translocation of heavy metals from soil to predatory insects via multi-tophic food chains can influence the growth, reproduction, metabolism and innate immune systems of the predators. This study was performed to observe the changes in energy metabolism and immune responses of Cryptolaemus montrouzieri feeding on heavy metal (Cd, Pb, Ni and Zn) contaminated pink hibiscus mealybug (Dysmicoccus neobrevipes). The average concentrations of Cd, Pb, Ni and Zn in mealybugs used for feeding assays were 30.57, 32.64, 31.47 and 33.19 mg/kg, respectively. The results showed a significant increase in total protein, glycogen, cholesterol and triglycerides content of C. montrouzieri feeding on heavy metals contaminated mealybugs compared with control groups. The activities of endogenous enzymes (acid phosphatase and alkaline phosphatase) as well as antioxidant enzymes (SOD, POD and CAT) were significantly higher in beetles feeding on heavy metals contaminated mealybugs. Our results provide basic insight into the influences of heavy metals (Cd, Pb and Ni) on energy metabolism and the innate immune system of the insect predator (C. montrouzieri) in a multi-trophic food chain. Further research on genetic processes involved in the regulation of metabolism and innate immune system of C. montrouzieri is still needed. [ABSTRACT FROM AUTHOR]

Aleurothrixus (formerly known as Aleurotrachelus) trachoides Back (Hemiptera: Aleyrodidae), commonly known as pepper or solanum whitefly, is a new emerging whitefly pest of several horticultural crops in the United States. During the preliminary survey for pepper whitefly infestation in Florida, a whitefly-specific predatory beetle Delphastus catalinae Horn (Coleoptera: Coccinellidae) was observed associated with this pest in the natural ecosystem. The current study was undertaken to determine the efficacy of this naturally occurring predator, D. catalinae, and an entomopathogenic fungus, Cordyceps (formerly known as Isaria) fumosorosea (Cfr) (Wize) (Hypocreales: Cordycipitaceae), alone or in combination, under controlled laboratory conditions. Whitefly mortality for Cfr (88%), beetle (100%) and Cfr + beetle (100%) treatments were similar and significantly higher compared to control. In the combination treatment, Cfr did not impact D. catalinae longevity and daily food intake, indicating a neutral interaction between the two treatments. Results showed that both of these natural biological control agents could potentially offer an effective alternative in the battle against invasive whiteflies such as pepper whitefly in U.S. horticulture production, either as a stand-alone strategy or in an integrated approach. Although these findings are promising, compatibility of the two treatments needs to be evaluated further under greenhouse and semi-field conditions before recommending to commercial growers.

The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation.

Many organisms show various geometric color patterns on their bodies, and the developmental, evolutionary, genetic, and ecological bases of these patterns have been intensely studied in various organisms. Ladybird beetles display highly diverse patterns of wing (elytral) color and are one of the most attractive model organisms for studying these characteristics. In this study, we reviewed the genetic history of elytral color patterns in the Asian multicolored ladybird beetle Harmonia axyridis from the classical genetic studies led by the pupils of Thomas Hunt Morgan and Theodosius Dobzhansky to recent genomic studies that revealed that a single GATA transcription factor gene, pannier, regulates the highly diverse elytral color patterns in this species. We also reviewed and discussed the developmental and evolutionary mechanisms driven by the pannier locus in H. axyridis. In the development sections, we focused on the following two topics: (a) how the red (carotenoid) and black (melanin) pigmentation of elytra is regulated by the pannier and pigmentation genes and (b) how the diverse color patterns are formed by integrating regulatory inputs from other genes involved in wing development. In the evolution section, we subsequently focused on the highly diversified DNA sequences within the first intron of pannier that are 56–76 kb long and that were generated through recurrent multiple inversions. Furthermore, we discussed how these recurrent inversions have driven the diversification of color patterns throughout evolution. We reviewed the genetic history of color patterns in Asian multicolored ladybird beetle, Harmonia axyridis, from the classical genetic studies to the modern genomics. In addition, we discussed regulatory models for color pattern formation and color pattern diversification in ladybird beetles based on the recent findings in the ladybird beetle genomic studies. [ABSTRACT FROM AUTHOR]

Ladybird beetles (Coleoptera: Coccinellidae), with broad morphological diversity, wide geographic distribution and substantial agricultural significance, are a challenging group for taxonomists and phylogenetics. As a promising tool to identify and discover new species, DNA barcoding might offer significant potential for identification, taxonomy and phylogeny of ladybird beetles. In the present study, a total of 1364 COI (cytochrome C oxidase subunit I) sequences representing 128 species from 52 genera of ladybird beetles were screened for barcoding evaluation and phylogenetic analysis. Our results from the barcoding analysis revealed that COI displays a similar level of species identification efficiency (nearly 90%) either based on Kimura two-parameter (K2P) distances calculation or on simplified neighbour-joining (NJ) tree construction. The phylogenetic relationships within the family Coccinellidae was analyzed by Bayesian-inference (BI) method. The phylogenetic results confirmed the monophyly of the subfamilies Microweisinae and Coccinellinae sensu Ślipiński (2007), and suggested that the subfamilies Coccidulinae, Chilocorinae and Scymninae are paraphyletic. However, the phylogenetic relationships among different subfamilies are not clearly defined and thus remain to be thoroughly studied. Overall, our study confirmed the usefulness of DNA barcoding for coccinellid species identification and phylogenetic inference. [ABSTRACT FROM AUTHOR]

Characterization of intraspecific variation is required to assess the potential nontarget effects of augmentative releases of Hippodamia convergens (Guerin) (Coleoptera: Coccinellidae) from the Western United States on local populations of this species in the Eastern United States. Adults of this predatory lady beetle species overwinter in adult reproductive diapause, thus examining responses to photoperiods can characterize geographic variation influencing their seasonal biology. This laboratory study quantified the induction and duration of adult reproductive diapause in five North American populations of H. convergens in response to four constant photoperiods (16:8, 14:10, 12:12, and 10:14 [L:D] h) at 22°C. Three populations were collected over a range of latitudes (31° N to 42° N) in the central portion of the United States (Texas, Kansas, and Iowa); two populations were purchased from commercial sources in the Western United States. All populations exhibited a long-day response to photoperiods: ≤17% of females reared at 16:8 (L:D) h entered diapause, whereas shorter photoperiods (12:12 and 10:14 [L:D] h) induced diapause in 82 to 100% of females. The response to 14:10 (L:D) h showed significant variation among the populations, ranging from 0 to 89% of females in reproductive diapause. Both the phenotypic variation in response to diapause inducing photoperiods and the genetic variation in North American populations of H. convergens document the geographic variability in this widely distributed predatory species. [ABSTRACT FROM AUTHOR]

Abstract: Functional response studies are often used to determine the suitability of predators as biocontrol agents. Ladybird beetles (Coleoptera: Coccinellidae) are often used for the control of crop pests such as aphids. However, most functional response studies on coccinellids compare a limited number of species at different life stages, temperatures or sexes. A large‐scale comparison of ladybird beetle functional responses is needed to evaluate the utility of these species as potential biocontrol predators and to understand the traits that influence the interaction strength between ladybird beetles and their prey. We compiled 158 ladybird beetle functional responses from 30 studies and tested for effects of taxa, traits, temperature and arena size on functional response parameters using linear mixed‐effects models. Our results show that functional response parameters (handling time and space clearance rate) are affected by predator stage, predator mass, prey type, temperature and arena size. Although complicated by interaction terms, space clearance rate generally increased with predator size, temperature and predator stage, while handling time decreased with predator size, temperature and predator stage. Coleopteran prey induced the highest handling times. Our results also show that experimental arena size has a large, consistent effect on space clearance rate. Arena size is more important in determining foraging rates at low prey densities than any other factor considered here, including predator mass and temperature. Efforts to use laboratory‐based functional response experiments to evaluate the efficacy of biocontrol predators are therefore confounded by the choice of arena size. Synthesis and applications. In addition to confirming known body mass and temperature effects, our study reveals previously unclear age‐related effects and the importance of prey types, which can be used to optimize biocontrol programmes. The arena size effect is unexpected and problematic because failure to account for arena size precludes accurate comparison of biocontrol predator effectiveness. We suggest managers and biocontrol practitioners re‐evaluate the efficacy of candidate biocontrol predators, perhaps by statistically controlling for arena size to minimize the influence of this widely unconsidered factor on functional response estimates. [ABSTRACT FROM AUTHOR]

The current studies were carried out to observe the variations in development, biology and life table parameters of ladybird beetle, Cryptolaemus montrouzieri, feeding on pink hibiscus mealybug ( Dysmicoccus neobrevipes ) contaminated with heavy metals (cadmium, lead, and nickel) bio-transferred across a multi-trophic chain. The developmental time required for immature life stages (1st, 2nd, 3rd, 4th instar nymphs, pupae) and total developmental period (egg-adult) differed significantly among different heavy metal treatments and control. The accumulated survival rate of C . montrouzieri immature life stages also differed significantly among different heavy metal treatments and control. Different parameters of adult female biology (Pre-oviposition period, fecundity, female longevity) were adversely affected by different heavy metals. Life table analysis revealed that all the heavy metals caused significant reduction in net reproduction rate (R 0 ) and intrinsic rate of increase (r) while the mean generation time (T) and doubling time (D t ) were significantly higher than control. The results obtained provide possible insight into the implications of heavy metals on the population dynamics of insect predator ( C . montrouzieri ) in a multi-trophic food chain. However, further research is required on genetic as well as physiological processes involved in the regulation of growth and development of C . montrouzieri. [ABSTRACT FROM AUTHOR]

The ladybird Cheilomenes sexmaculata is reported for the first time from Colombia. Previously, this species was recorded in Asia and Australia, then introduced to South America and reported from countries such as Chile, Ecuador, Perú, and Venezuela, where it is used for biological control. [ABSTRACT FROM AUTHOR]

Long-term changes in the collection season ofMenochilus sexmaculatus(Fabricius) were analysed based on 265 specimens collected from the Kansai district, central Japan, during 1949–2004. Results show that collection records in the summer months, July and August, decreased during this period, and that there were no summer records from 2000 to 2004. Concurrently, the annual mean and summer temperatures tended to increase and summer humidity decreased during this period in the Kansai district. Thus, the activity ofM. sexmaculatuswould be limited in summer because of the recent climate warming. [ABSTRACT FROM AUTHOR]

The relationship between a coccinellid beetle (Coccinella septempunctata L.) and four different aphid species (spinach aphid, Aphis fabae Scopoli; coriander aphid, Hyadaphis coriandri (Das); cabbage aphid, Brevicoryne brassicae L.; pea aphid, Acyrthosiphon pisum Harris) was evaluated in the laboratory in no choice and free choice feeding assays. In the no choice feeding assay, the stages of beetle (adults, 3rd and 4th instar) consumed more aphids than early stages (1st and 2nd instar). In the free choice feeding assay, the consumption of pea aphid (77.647) was statistically high followed by spinach (66.276), coriander (66.14) and cabbage (61.48) aphids. Manly's preference index suggest that pea aphid was the most preferred (by all stages of C. septempunctata) aphid species followed by coriander, and the cabbage aphid was the least preferred species. The results of the present study revealed predatory potential of C. septempunctata against different aphid species under the laboratory conditions. The results could be helpful in designing biological management strategies for aphids. [ABSTRACT FROM AUTHOR]

A new species of Scymnobius Casey (Coleoptera, Coccinellidae, Scymnini) from Pernambuco, Brazil. Scymnobius pernambucensis sp. nov. from Pernambuco, Brazil, is described and illustrated. This is the third species of this genus recorded from Brazil.

Transmission of plant pathogens through insect vectors is a complex biological process involving interactions between the host plants, insects, and pathogens. Simultaneous impact of the insect damage and pathogenic bacteria in infected host plants induce volatiles that modify not only the behavior of its insect vector but also of their natural enemies, such as parasitoid wasps. Therefore, it is essential to understand how insects such as the predator ladybird beetle responds to volatiles emitted from a host plant and how the disease transmission alters the interactions between predators, vector, pathogens, and plants. In this study, we investigated the response of Propylaea japonica to volatiles from citrus plants damaged by Diaphorina citri and Candidatus Liberibacter asiaticus through olfactometer bioassays. Synthetic chemical blends were also used to determine the active compounds in the plant volatile. The results showed that volatiles emitted by healthy plants attracted more P. japonica than other treatments, due to the presence of high quantities of D-limonene and beta-ocimene, and the lack of methyl salicylate. When using synthetic chemicals in the olfactory tests, we found that D-limonene attracted P. japonica while methyl salicylate repelled the predator. However, beta-ocimene attracted the insects at lower concentrations but repelled them at higher concentrations. These results indicate that P. japonica could not efficiently search for its host by using volatile cues emitted from psyllids- and Las bacteria-infected citrus plants. [ABSTRACT FROM AUTHOR]

The incidence of sibling cannibalism in clutches of Harmonia axyridis infected by the male-killing Spiroplasma was compared with that in uninfected clutches, and the way in which fitness compensation was realized by sibling cannibalism was investigated. Primarily the rate of sibling cannibalism was determined by the hatching rate as all unviable eggs were consumed both in infected and uninfected clutches. Per capita consumption of roughly 0.1 individuals was estimated for uninfected clutches in the present study, as compared to 0.3 individuals in previous studies. The per capita consumption in infected clutches was 1.4, showing that the male-killing behavior of the Spiroplasma provides an approximately 4-14 fold increase in the chance of sibling cannibalism. Both in infected and uninfected clutches, the median of the starting time of sibling cannibalism was soon after that of the completion of hatching. Larvae started to disperse from their egg clutches only about 7.5-8.5 h after the initiation of hatching. These time sequences indicate that sibling cannibalism occurs at the earlier stage of the hatching process and the density of aphids in the area has little or no influence on incidence of the sibling cannibalism. During the maintenance of the infected line for five generations, exclusively females were produced and the median of the hatching rate was 0.395, suggesting a very high rate of vertical transmission of the Spiroplasma infection. Although the measurement of other parameters, such as the effect of Spiroplasma infection on fecundity or longevity, are necessary, the high compensation rate shown in the present study, together with the very high vertical transmission, may explain the prevalence of the present male-killing agent in the local populations of the ladybird beetle.