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Xenos is a strepsipteran genus parasitizing hornets of the Vespa spp. In Japan, parasitism levels in hornets have been examined for two Xenos species. These studies have indicated that parasitism levels vary with the seasons but are inconsequential compared to other potential factors that reduce the number of host colonies. However, a comprehensive analysis of parasitism levels accounting for various factors such as host species, seasons, and years was not conducted. To address this gap, we conducted a four-year study in which we collected Vespa spp. using bait traps and assessed parasitism levels concerning those factors. Additionally, we evaluated the number of male and female Xenos parasites throughout the seasons. A total of 11,766 wasps from six hornet species were collected, with three of the species conspicuously parasitized by two Xenos parasites: Vespa analis (Fabricius, 1775) parasitized by Xenos oxyodontes (Nakase & Kato, 2013) and Vespa mandarinia (Smith, 1852) and Vespa ducalis (Smith, 1852) parasitized by Xenos moutoni (Buysson, 1903). Levels of parasitism by X. oxyodontes exceeded those by X. moutoni. Seasonal and yearly variations influenced the levels of parasitism by the two Xenos spp. We observed that male and female Xenos parasites emerged simultaneously over 2 – 3 months, suggesting the likelihood of multivoltinism in temperate regions. Our study also examined several key factors influencing the fluctuations in the population size of these parasites.

Simple Summary: Species interact with each other in many ways, such as predation, mutualism, or competition, ultimately affecting each other's evolution, reducing the negative effects of these interactions and/or increasing the positive ones. We studied a parasitic fly that uses different katydid species as hosts for its larvae sequentially at different times during its breeding season. The fly larvae kill the host when they emerge, setting up multiple arms races between the fly and each of the hosts. The hosts are selected to ameliorate the negative impact of parasitism, whereas the parasitoid is selected to use all host species well for the population to persist. We compared host use and the ability of fly pupae to develop into adults across four katydid hosts. The parasitism rate varied between ~14% and 73%, yet host use was similar for many larval measurements across hosts. However, one species was a particularly poor host for the fly based on fly pupa development. We suggest that currently, this poor host strongly influences the evolution of the fly in this arms race to improve its utilization of this host. Understanding how species interact and affect each other is important to predict their evolution and manage species of human relevance, such as parasites, plant pests, or vectors of disease. Antagonistic species relationships such as parasitoid/host interactions lead to evolutionary arms races between species. Many parasitoids use more than one host species, requiring the parasitoid to adapt to multiple hosts, sometimes being the leader or the follower in the evolutionary back-and-forth between species. Thus, multi-species interactions are dynamic and show temporary evolutionary outcomes at a given point in time. We investigated the interactions of the multivoltine parasitoid fly Ormia lineifrons that uses different katydid hosts for each of its fly generations sequentially over time. We hypothesized that this fly is adapted to utilizing all hosts equally well for the population to persist. We quantified and compared the fly's development in each of the four Neoconocephalus hosts. Cumulative parasitism rates ranged between ~14% and 73%, but parasitoid load and development time did not differ across host species. Yet, pupal size was lowest for flies using N. velox as a host compared to N. triops and other host species. Successful development from pupa to adult fly differed across host species, with flies emerging from N. triops displaying a significantly lower development success rate than those emerging from N. velox and the other two hosts. Interestingly, N. triops and N. velox did not differ in size and were smaller than N. robustus and N. nebrascensis hosts. Thus, O. lineifrons utilized all hosts but displayed especially low ability to develop in N. triops, potentially due to differences in the nutritional status of the host. In the multi-species interactions between the fly and its hosts, the poor use of N. triops may currently affect the fly's evolution the most. Similarities and differences across host utilization and their evolutionary background are discussed. [ABSTRACT FROM AUTHOR]

The eighteen (18) F1 hybrid combinations were tested to identify potential combinations adaptable to type 1 climatic conditions in the Philippines. The six (6) bivoltine purelines (DMMMSU 108, DMMMSU 109, DMMMSU 110, DMMMSU 111, DMMMSU 113, and DMMMSU 119); and three (3) multivoltine purelines (DMMMSU 1000, DMMMSU 1007, and DMMMSU 1014), were crossed (multivoltine x bivoltine) in a mating plan. These were arranged in a Completely Randomized Design (CRD), replicated three times, and analyzed using Analysis of Variance (ANOVA). A test of significance was done using ANOVA across years and Tukey's Honest Significant Difference Test (HSD). The multiple trait evaluation index (EI) method was also used in the identification of potential F1 hybrids. Three major phases were done: (1) parental rearing of multivoltine and bivoltine pure lines for breed multiplication; (2) hybridization process; and (3) evaluation of F1 hybrids. Rearing evaluations were conducted for three consecutive years. Based from the three evaluations, 10 potential crosses were identified: DMMMSU MV-12, DMMMSU MV-11, DMMMSU MV-13, DMMMSU MV-16, DMMMSU MV-07, DMMMSU MV-14, DMMMSU MV-05, DMMMSU MV-09, DMMMSU MV-03, and DMMSU MV-10. The topmost combinations with the best economic and commercial characters and are consistently adaptable during two (2) cropping seasons were DMMMSU MV-07, DMMMSU MV-12, DMMMSU MV-05, DMMMSU MV-09 and DMMMSU MV-11. These newly-identified F1 hybrids are considered potential breeds that could improve cocoon production. [ABSTRACT FROM AUTHOR]

Antagonistic species relationships such as parasitoid/host interactions lead to evolutionary arms races between species. Many parasitoids use more than one host species, requiring the parasitoid to adapt to multiple hosts, sometimes being the leader or the follower in the evolutionary back-and-forth between species. Thus, multi-species interactions are dynamic and show temporary evolutionary outcomes at a given point in time. We investigated the interactions of the multivoltine parasitoid fly Ormia lineifrons that uses different katydid hosts for each of its fly generations sequentially over time. We hypothesized that this fly is adapted to utilizing all hosts equally well for the population to persist. We quantified and compared the fly’s development in each of the four Neoconocephalus hosts. Cumulative parasitism rates ranged between ~14% and 73%, but parasitoid load and development time did not differ across host species. Yet, pupal size was lowest for flies using N. velox as a host compared to N. triops and other host species. Successful development from pupa to adult fly differed across host species, with flies emerging from N. triops displaying a significantly lower development success rate than those emerging from N. velox and the other two hosts. Interestingly, N. triops and N. velox did not differ in size and were smaller than N. robustus and N. nebrascensis hosts. Thus, O. lineifrons utilized all hosts but displayed especially low ability to develop in N. triops, potentially due to differences in the nutritional status of the host. In the multi-species interactions between the fly and its hosts, the poor use of N. triops may currently affect the fly’s evolution the most. Similarities and differences across host utilization and their evolutionary background are discussed.

The generalized abundance index (GAI) provides a useful tool for estimating relative population sizes and trends of seasonal invertebrates from species' count data and offers potential for inferring which external factors may influence phenology and demography through parametric descriptions of seasonal variation. We provide an R package that extends previous software with the ability to include covariates when fitting parametric GAI models, where seasonal variation is described by either a mixture of Normal distributions or a stopover model which provides estimates of life span. The package also generalizes the models to allow any number of broods/generations in the target population within a defined season. The option to perform bootstrapping, either parametrically or nonparametrically, is also provided. The new package allows models to be far more flexible when describing seasonal variation, which may be dependent on site‐specific environmental factors or consist of many broods/generations which may overlap, as demonstrated by two case studies. Our open‐source software, available at https://github.com/calliste‐fagard‐jenkin/rGAI, makes these extensions widely and freely available, allowing the complexity of GAI models used by ecologists and applied statisticians to increase accordingly. [ABSTRACT FROM AUTHOR]

Abstract The generalized abundance index (GAI) provides a useful tool for estimating relative population sizes and trends of seasonal invertebrates from species' count data and offers potential for inferring which external factors may influence phenology and demography through parametric descriptions of seasonal variation. We provide an R package that extends previous software with the ability to include covariates when fitting parametric GAI models, where seasonal variation is described by either a mixture of Normal distributions or a stopover model which provides estimates of life span. The package also generalizes the models to allow any number of broods/generations in the target population within a defined season. The option to perform bootstrapping, either parametrically or nonparametrically, is also provided. The new package allows models to be far more flexible when describing seasonal variation, which may be dependent on site‐specific environmental factors or consist of many broods/generations which may overlap, as demonstrated by two case studies. Our open‐source software, available at https://github.com/calliste‐fagard‐jenkin/rGAI, makes these extensions widely and freely available, allowing the complexity of GAI models used by ecologists and applied statisticians to increase accordingly.

Multivoltine insects can produce multiple generations in one year. Favorable conditions support more generations, leading to serious outbreaks. For herbivores, plant nutrient availability is a major environmental factor affecting fitness and it can shift substantially throughout seasons. In a stochastic environment, organisms can adopt several strategies to regulate their nutrient intake and maximize performance. However, data regarding nutrient regulation of wild herbivores are scarce, and even more so regarding potential intergenerational plasticity. To bridge this gap, we measured nutritional regulation and performance of an outbreaking multivoltine herbivore – one of the most serious agricultural pests in the Sahel: Oedaleus senegalensis. We surveyed a field population in Senegal and measured its nutritional preference and regulation across two generations (G1 and G3) using artificial diets and plant choice experiments. In the field, G1 locusts were five to ten times more abundant than G3 locusts. We found that G1 and G3 locusts selected different protein:carbohydrate ratios but also that the strength of regulation was different. G1 locusts regulated their nutrient target more tightly than G3 locusts. In contrast, studies with laboratory populations demonstrate strong regulation for grasshoppers, appearing less plastic than field populations. Both generations selected a carbohydrate‐biased nutrient ratio, although it was more carbohydrate‐biased for G3 locusts. In both cases, plant nutrient contents in the field were more protein biased than their preferred diet. Therefore, choices by locusts were likely influenced by other ecological variables such as leaf toughness or plant defenses. G1females were heavier and laid more eggs than G3 females. However, G3 locusts survived longer during the experiment than G1 locusts, suggesting a potential generational tradeoff between reproduction and survival. Our data highlight the importance of studying nutritional regulation in situ and incorporating field and lab data to better understand foraging decisions and nutritional tradeoffs. [ABSTRACT FROM AUTHOR]

In silkworm breeding, numerous traits are considered as important for improving them to increase the benefits to silk producers. An attempt was made to correlate the lifespan of adult stage of silkworm Bombyx mori multivoltine races with the few yield parameters are found to be significant in deciding the next generation yield. The adult life span was correlated with larval weight, cocoon weight, shell weight, shell percentage and filament length in the six multivoltines. Based on the Pearson correlation co-efficient estimations, there is correlation between adult longevity and larval weight. There is strong correlation between adult longevity and three cocoon characters namely cocoon weight, shell weight and shell percentage. Insignificant correlations were observed among six races selected between adult life span and filament length. But the R2 values are on the lower side in the multivoltine. Three groups were identified among six multivoltines from the correlation studies. I group involves pre and npnd races with less R2 values where as II group includes C.nichi, Nistari and PM with moderate R2 values. However, Daizo race recorded highest R2 values. The results obtained in the present studies clearly demonstrates that there is significant correlation between adult longevity and four economic traits, larval weight, cocoon weight, shell weight, shell percentage. However for the trait filament length such correlation could be possible only among selected breeds/hybrids. [ABSTRACT FROM AUTHOR]

Different gall inducers belonging to distinct insect orders are rarely known to induce similarly shaped galls on the same host plant organs. We report that Asphondylia tojoi Elsayed & Tokuda sp. nov. (Diptera: Cecidomyiidae) and Ceratoneura sp. (Hymenoptera: Eulophidae) induce galls on leaf buds of Schoepfia jasminodora Sieb. et Zucc. (Schoepfiaceae). We describe the gall midge species as new to science and report a phylogenetic analysis for known Japanese Asphondylia species. We also describe life histories of the two species, based on monthly surveys during 2015-2017: although both species are multivoltine, A. tojoi overwinters as first instars in galls, whereas Ceratoneura sp. possibly does so as adults outside the galls. In addition, the internal structure of galls differed between the two species. Galls containing A. tojoi consist of a single chamber with inner walls clearly covered with whitish fungal mycelia after the gall midges develop into second instars. Those containing the Ceratoneura sp. have multiple chambers with hard black inner walls. Although some eulophids are known to be inquilines of galls induced by Asphondylia species, we consider that the Ceratoneura sp. is probably a true gall inducer because of the different gall structure and absence of fungal mycelia in their galls. This is the first report detailing the annual life history of a Ceratoneura species. Asphondylia tojoi represents the first example of monophagous Asphondylia species with a multivoltine life history on a deciduous tree. [ABSTRACT FROM AUTHOR]

Silkworm Seed Technology Laboratory, Kodathi is producing P2 Dfls through race maintenance programme in limited manner to supply selected basic seed farms to rear and generate P1 seed cocoons for hybrid preparation to West Bengal in the event of seed crop failures. In the present investigation, Nistari ecotypes Chalsa, Balapur and Debra, M6DPC were evaluated almost for 5 years. The mean performance of these breeds were shown significant dilferences for the majority of the traits with excellent pupation rate. The effective rate of rearing/10,000 larvae (ERR) by is 8927 in Chalsa, 9118 in Balapur, 8898 in Debra and 8843 in M6DPC.The ERR by weight is 8.96 Kg in Chalsa, 8.66 Kg in Balapur, 8.61 Kg in Debra and 7.92 in M6DPC.The cocoon weight in Chalsa 0.800g, and l.OOg in Balapur, 1.020g in Debra, 1.060 and in M6DPC.The cocoon shell weight in Chalsa is 0.150 and in Balapur 0.150g, in Debra 0.140 and 0.140 in M6DPC. Cocoon shell ratio in Chalsa is 14.45%, in Balapur 14.42%, in Debra 14.72% and in M6DPC is 13.91. Pupation rate in Chalsa is 90.58%, in Balapur 94.15% and in Debra 95.58% and 94.65% in M6DPC. Evaluation of these P2 dfls of Nistari (Chalsa, Balapur and Debra) in West Bengal at selected basic seed farms indicated 36.05 Kg/100 dfls with a good pupation rate of 95.7%. In Tamil Nadu, Nistari (Chalsa) revealed an average yield of41.89 Kg/100 dfls with 95% pupation. In case of M6DPC, it revealed an average yield of 45.12 Kg/lOOdfls with pupation rate of 94% and other traits are on par with laboratory performance. In Andhra Pradesh, an average yield of 52.03 Kg/100 dfls (Chalsa) with 96.6% pupation rate and excellent economic traits is indication for quality seed cocoons to realize the benefit of hybrid vigour at commercial level. [ABSTRACT FROM AUTHOR]

The present study was undertaken to quantify haemolymph content in different breeds of silkworm, Bombyx mori L under Kashmir climatic conditions. The results revealed that blood volume varies widely among the different breeds of mulberry silkworm. Nistari registered the significantly high haemolymph content of 5120.00µl and 5315.00 µl during spring and summer seasons respectively, while among the bivoltine breeds, SKUAST-28 was found to register the maximum haemolymph content of 4112.50 µl and 3965.00 µl during spring and summer seasons, respectively. [ABSTRACT FROM AUTHOR]

The study of an insect's life cycle is important to understand the abundance, diversity, development and the environment in which it lives. To date, only limited investigations have been conducted in Malaysia on the mayfly Baetis, a genus of ephemeropterans. Here, we report a study on the larval instar determination and secondary production of Baetis idei in four rivers in the Bukit Merah catchment area, Perak. Samples were collected monthly from May 2014 until April 2015 using the kick-net and drag methods. B. idei displayed nine instar stages on a discriminant function analysis (DFA) scatter plot. Based on an analysis of nymphal body length and the emergence time of early and final larva instar, B. idei was found to be multivoltine in the Ara, the Jelai, Kurau and Ayer Itam rivers. The estimated annual production of B. idei in the four rivers ranged from -3.64 mg m-2 y-1 to 15.35 mg m-2 y-1 and the annual P/B ratio varied from -2.14 to 1.56. The highest turnover ratio for this species was recorded in Ara River. Different types of habitat and substrate at each river determined the abundance, voltinism, and secondary production of B. idei in the four rivers. [ABSTRACT FROM AUTHOR]

Experience of insect herbivores and their natural enemies in the natal habitat is considered to affect their likelihood of accepting a similar habitat or plant/host during dispersal. Growing phenology of food plants and the number of generations in the insects further determines lability of insect behavioural responses at eclosion. We studied the effect of rearing history on oviposition preference in a multivoltine herbivore (Pieris brassicae), and foraging behaviour in the endoparasitoid wasp (Cotesia glomerata) a specialist enemy of P. brassicae. Different generations of the insects are obligatorily associated with different plants in the Brassicaceae, e.g., Brassica rapa, Brassica nigra and Sinapis arvensis, exhibiting different seasonal phenologies in The Netherlands. Food plant preference of adults was examined when the insects had been reared on each of the three plant species for one generation. Rearing history only marginally affected oviposition preference of P. brassicae butterflies, but they never preferred the plant on which they had been reared. C. glomerata had a clear preference for host-infested B. rapa plants, irrespective of rearing history. Higher levels of the glucosinolate breakdown product 3-butenyl isothiocyanate in the headspace of B. rapa plants could explain enhanced attractiveness. Our results reveal the potential importance of flexible plant choice for female multivoltine insects in nature. [ABSTRACT FROM AUTHOR]

ABSTRACT Thermal alteration is associated with ecological change in freshwater systems. Global climate change is likely to amplify thermal stresses on aquatic systems. We used cumulative daily heat units to examine potential impacts of temperature changes on selected aquatic organisms using scenario analyses. We selected two species of aquatic macroinvertebrates to test our hypotheses of thermal effects on life history pattern, viz. a univoltine stenothermic ephemeropteran species of conservation importance, and a multivoltine dipteran pest species. A combination of spreadsheet probability and logistic regression models was used to model probabilities of hatching and breeding success, plus population sizes and generation numbers per month, under current and projected 2 °C warmer water temperature scenarios. We propose that cold-adapted Gondwanaland relic species are likely to become increasingly vulnerable and range limited, whereas multivoltine pest species are likely to become more abundant under scenarios of increased water temperatures. We propose management options that include maintaining river connectivity and dam re-operation as potential mitigation measures. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The ability of silk yarns to take up twist without deterioration has been studied in terms of breaking twist angle. The study has brought to focus certain important aspects with regard to the torsional rigidity and the brittleness of silk yarns. It is observed that the brittleness of bivoltine is significantly higher than that of multibivoltine. The denier of raw silk has a significant beating on its brittleness. Coarser deniers exhibit higher brittleness in the case of both multibivoltine and bivoltine. It is also observed that the brittleness of non-mulberry silk is significantly different from that of mulberry silk for a given denier. Muga has the lowest brittleness, tasar is next lower and mulberry raw silk has the highest brittleness. Thus, non-mulberry silks have a better ability to take twists without being affected. [ABSTRACT FROM AUTHOR]

The body-size distributions and biomass estimates of Caenis (Ephemeroptera: Caenidae), Cloeon (Ephemeroptera: Baetidae), Coenagrionidae (Odonata), Micronecta (Hemiptera: Corixidae), Chironominae (Diptera: Chironomidae) and Orthocladiinae (Diptera: Chironomidae), the most common and abundant insect taxa associated with a submerged macrophyte Lagarosiphon ilicifolius in Lake Kariba, are presented. Caenis has a univoltine life cycle, whilst Cloeon, Coenagrionidae, Chironominae and Orthocladiinae have multivoltine life cycles. Growth and reproduction of Micronecta occurred all year round. The Coenagrionidae had the highest mean biomass, which was significantly greater than those of the other taxa. Caenis and Orthocladiinae were sensitive to variations in water temperature and dissolved oxygen (DO) concentration, their highest biomasses occurring when temperatures were low and DO concentrations high. The biomasses of Chironominae and Orthocladiinae increased with rising water levels, but that of Caenis decreased. Total insect biomass was minimally affected by variations in water physico-chemical variables. The study suggests that water temperature, water level and DO concentration do have an effect on the biomasses of some insect taxa associated with Lagarosiphon in Lake Kariba. Mixing processes during de-stratification also affect the abundance and biomass of the insect taxa. [ABSTRACT FROM PUBLISHER]

Abstract: Molecular mechanism controlling egg diapause remains obscure in silkworm, Bombyx mori. An attempt is made to decipher various molecular events occurring during embryonic diapause in multivoltine silkworm, B. mori. Using suppressive subtractive hybridization (SSH), 186 cDNA clones isolated from both diapause and nondiapause eggs were sequenced. Of the sequenced clones, 29 matched with silkbase entries and these identified putative genes were classified into six functional groups such as regulatory, food utilization, stress response, metabolic, ribosomal and transposable elements. Among these genes, twelve belonged to regulatory group while, one taste receptor type 2 member 117 gene was related to food utilization. One heat shock cognate 70kDa protein and 3 of the ubiquitin family were identified under stress response category. Similarly, four genes were identified as metabolic genes, 3 belonging to chitin family and one propanediol utilization protein. Of the seven genes identified in ribosomal groups, most of them were 60s ribosomal protein subunits. However, one negative regulation of transcription gene identified was a transposable element. The qPCR analysis confirmed the expression of 21 of the above genes, wherein, 6 were upregulated during diapause, 12 during non-diapause, while, 3 remained unchanged. [Copyright &y& Elsevier]

Abstract: Partially purified red fluorescent proteins (RFPs) secured from the gut juice of 5th-instar multivoltine and bivoltine silkworm races were observed as several bands in electrophoretograms and chromatographic eluates. Interestingly, different races of silkworms had varying numbers of fluorescent protein bands: 11 in Pure Mysore (resistant), 11 in Nistari (resistant), 4 in CSR2 (moderately susceptible) and 1 in NB4D2 (highly susceptible). Bioassay experiments indicated that the fluorescent bands had antinucleopolyhedrovirus (antiNPV) activity. The molar extinction coefficients and fluorescence quantum yields of all RFPs were estimated. The purified tetrapyrroles were characterized by UV–visible absorption and fluorescence spectral analyses. All tetrapyrrole moieties associated with RFPs were found to be different and characteristic of the fluorescent bands. The resulting qualitative and quantitative differences among the individual RFPs from various races of silkworm were related to the susceptibilities of the silkworms to the viral disease. Moreover, light was found to be essential for the synthesis of RFPs, and, therefore, the role of light in the synthesis of RFPs was evaluated. Thus, this work may elucidate the process of RFP synthesis in silkworm, which may be used as a biomarker to measure the degree of susceptibility of silkworm races to NPV. Therefore, the characteristic band pattern may be used as an indicator to define the relative resistance of a race towards the specific virus. [Copyright &y& Elsevier]

The article offers a study of the seasonal occurrence of grasshoppers' life stages in the southern Pampas, Argentina. It says that several species, including Aleuas lineatus, Boellia bruneri, and Dichroplus conspersus, spent winter in the egg stage, and younger nymphs occur in mid-spring, from October to November. It states that nymphs become abundant in winter, from November to mid-December, while adults are dominant in mid-autumn, from March to April.

Abstract: Platygaster robiniae Buhl and Duso (Hymenoptera: Platygastridae) is a gregarious, koinobiont endoparasitoid of the locust gall midge, Obolodiplosis robiniae (Haldeman) (Diptera: Cecidomyiidae). P. robiniae is an egg-larval parasitoid, parasitizing eggs of O. robiniae and emerging from the host larvae. The eggs of the wasp develop monembryonically with a prolonged embryonic stage. After hatching, the parasitoid undergoes only two larval instars, and total development time from egg to adult takes about 28days to complete. The life cycle of a parasitoid generation is synchronized with that of its host; the adult wasps’ emergence coincides with that of the host, so that they can parasitize the host eggs. [Copyright &y& Elsevier]

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The rice leaf bug, Trigonotylus caelestialium (Kirkaldy) (Heteroptera: Miridae), is an important insect pest, causing pecky-rice damage in Japan. This bug has a multivoltine life cycle and feeds on various species of the Poaceae. The phenology of the host-plants differs between species and the plant quality of a single host species may change with the seasons. The fitness of the bug may be affected by these seasonal changes in host-plant quality. In the current study, the effects of such quality changes on adult and nymphal performance were examined using a population of bugs collected in Joetsu, Niigata, Japan. Rearing of newly emerged adults collected from spring to autumn from Italian rye grass, Lolium multiflorum Lam., and southern crabgrass, Digitaria ciliaris (Retz.), showed that body size and performance of adults differed between collection seasons and plant species, indicating that nymphal conditions including host-plant quality have crucial effects on their fitness. Rearing nymphs from hatching to adult emergence on various field-collected grasses under laboratory conditions showed that the performance of nymphs depends on the plant species and varies greatly with the season, within a given species. In general, nymphs performed more poorly on most of the plants collected late in the season, but they performed well on some plants unavailable early in the season. Therefore, in T. caelestialium, seasonal and spatial variations are important factors that affect fitness of nymphs and adults, and this suggests that oviposition of diapause eggs in summer is an adaptation to deteriorating food conditions. [ABSTRACT FROM AUTHOR]

Diapause hormone (DH) and pheromone biosynthesis-activating neuropeptide (PBAN) code for the diapause gene (DH-PBAN) of Bombyx mori Linnaeus. The DH-PBAN gene sequence from the BLAST database was searched against B. mori genomic gene sequences for similarity. Results showed maximum homology with a genomic contig (accession no. D16230). Primers were designed for the intron, exon and promoter regions of the DH-PBAN gene sequence. The corresponding regions were amplified using genomic DNA as template and products of diapause and non-diapause silkworm races were compared. There was no variation in the 425 bp intron and 254 bp exon regions. However, 1.3% nucleotide sequence variation was observed in selected silkworm races. The promoter region-showed 4.2% single nucleotide variation in the diapause and nondiapause silkworm races. The promoter region of the diapause gene showed variations in the sequence of the POU (Pit 1, Oct 1 and Unc-86)-binding site of non-diapause and diapause races of B. mori. In phylogenetic analysis, B. mori formed a cluster with other silkworms of the Bombycidae family, whereas the Noctuidae family formed a separate cluster, indicating that the diapause gene is conserved across the insect taxa. [ABSTRACT FROM AUTHOR]

In 2001, subconical galls were found on the leaves of an alien Artemisia species (Asteraceae) in Ibusuki City, Kagoshima Prefecture, Japan. These galls were quite similar to those induced by Rhopalomyia yomogicola (Diptera: Cecidomyiidae) on Artemisia princeps, Artemisia montana, and Artemisia japonica in Japan. The morphological features of the pupal head and molecular sequencing data indicated that the gall midge from the alien Artemisia was identical to R. yomogicola. Usually, galling insects do not expand readily their host range to alien plants, but R. yomogicola is considered to have expanded its host range to the alien Artemisia by its multivoltine life history trait and oligophagous habit across two different botanical sections of the genus Artemisia. Adult abdominal tergites and sternites and immature stages of R. yomogicola are described for the first time and detailed biological information is presented. [ABSTRACT FROM AUTHOR]

1. We used published data to investigate the combined influence of egg size and incubation temperature on embryonic development time for a broad assortment of aquatic insects at four different incubation temperatures (10, 15, 20 and 25 °C). 2. Embryonic development time (EDT) was positively correlated with egg size at each of the four temperatures, but with different relationships for univoltine and multivoltine aquatic insects. The relationships of embryonic development time to egg size expressed in degree-days did not significantly differ in slope (P>0.50) or intercept (P>0.05) for either univoltine or multivoltine aquatic insects at each of the four temperatures. 3. The relationship of embryonic development time (degree-days) to egg mass in multivoltine aquatic insects (EDT=885×0.19, P<0.0001, r2=0.48) is similar in slope and intercept to that for other oviparous animals (i.e., zooplankton, fish, amphibians and reptiles), and to the relationship of embryonic development time to neonate mass in mammals. Univoltine species on average require 3–5 times longer to develop (EDT=14190×0.29, P<0.001, r2=0.29) than most other animals of equivalent egg mass, but the relationship of embryonic development time to egg mass is similar in slope to that of most other animals. Together, these relationships provide a basis for evaluating differences in embryonic development time among aquatic insects. [ABSTRACT FROM AUTHOR]

Middle and posterior parts of the silk gland of fifth instar bivoltine and multivoltine races of Bombyx mori and their hybrid were analysed for the concentration of fibroin, DNA, RNA and total protein. Fibroin content of the silk gland increased rapidly from the beginning of fifth instar upto the spinning stage. Concentration of DNA in the middle silk gland was maximum at 24 hr and decreased thereafter. In the posterior silk gland, the concentration of DNA increased upto 72 hr and then decreased, RNA concentration was maximum at 72 hr and 120 hr, in the middle and posterior silk gland respectively. The total protein content increased gradually upto the spinning stage in the middle silk gland whereas it increased upto 120 hr and decreased sharply thereafter in the posterior silk gland. The difference in the concentration of these constituents in the silk gland was correlated with the differential silk output in both the pure races and their hybrid. [ABSTRACT FROM AUTHOR]

Pisoxylon amenkei is a specie of solitary wasp that builds its nests in pre-existing cavities; it has only been recorded nesting in the Araucaria forest, one of the Atlantic forest phytophysiognomies and a biodiversity hotspot. So far, the only information on the biology of the genus Pisoxylon is based on one species. In addition, the genus has many similarities to Trypoxylon , showing an increased need for studies on the biology of these species of wasps. In the present study, we introduce unpublished information about Pisoxylon amenkei nesting biology and described many aspects of its natural history. Research was carried out between August 2017 and August 2019, in a rural area of Guarapuava municipality, Paraná, Brazil. Pisoxylon amenkei nested only in fragmented parts of Araucaria forest, during summer and autumn. It is a multivoltine species, and thus remains in diapause, in the pre-pupa phase during winter and spring. Their nests had an interior design similar to that of Pisoxylon xanthosoma and some Trypoxylon species, such as Trypoxylon lactitarse and Trypoxylon agamenon . Moreover, the sex ratio of P. amenkei was 1: 1, which can be linked to an equal cost in the production of females and males. Like other species of Pisoxylon , P. amenkei nests primarily in forest areas. In southern Brazil, it nests in fragments of Araucaria forest, which are threatened. Therefore, more efforts are needed to preserve these remaining fragments; a failure to do so could have devastating results, considering the number of threatened species that these forests house. We conclude that further studies should focus on the phylogeny of the group and use molecular analyses to clarify the hypothesis of Antropov (1998), that Pisoxylon should be classified as a subgenus of Trypoxylon .

Experience of insect herbivores and their natural enemies in the natal habitat is considered to affect their likelihood of accepting a similar habitat or plant/host during dispersal. Growing phenology of food plants and the number of generations in the insects further determines lability of insect behavioural responses at eclosion. We studied the effect of rearing history on oviposition preference in a multivoltine herbivore (Pieris brassicae), and foraging behaviour in the endoparasitoid wasp (Cotesia glomerata) a specialist enemy of P. brassicae. Different generations of the insects are obligatorily associated with different plants in the Brassicaceae, e.g., Brassica rapa, Brassica nigra and Sinapis arvensis, exhibiting different seasonal phenologies in The Netherlands. Food plant preference of adults was examined when the insects had been reared on each of the three plant species for one generation. Rearing history only marginally affected oviposition preference of P. brassicae butterflies, but they never preferred the plant on which they had been reared. C. glomerata had a clear preference for host-infested B. rapa plants, irrespective of rearing history. Higher levels of the glucosinolate breakdown product 3-butenyl isothiocyanate in the headspace of B. rapa plants could explain enhanced attractiveness. Our results reveal the potential importance of flexible plant choice for female multivoltine insects in nature.