Search

Functional diversity research enhances our understanding of ecosystems and both their functioning and their responses to environmental variations. This study investigated the biological trait responses of benthic invertebrate communities to various environmental conditions in estuarine habitats. We analyzed benthic macroinvertebrate communities in freshwater and estuarine environments to compare their characteristics between estuary sites with and without artificial barriers. Moreover, we combined taxonomic analyses (species richness, abundance, and four community indices) with functional diversity indices and biological trait analyses. The major results are as follows: (i) the most important environmental factors shaping species distribution in estuarine habitats were salinity and electrical conductivity; (ii) comparing functional diversity indices, tidal estuaries revealed that seawater intrusion induced changes in species distribution and the dispersion of benthic macroinvertebrates; (iii) the presence or absence of artificial barriers in estuaries affected biological traits owing to the influence of specific functional strategies of certain species. Consequently, the presence or absence of artificial barriers in estuaries can lead to significant changes in habitat connectivity and functional diversity related to ecosystem functions. These findings indicate that the presence of artificial barriers can significantly influence the ecological dynamics of estuarine ecosystems, thereby affecting species distribution, functional diversity and habitat connectivity. Understanding these effects contributes to a more comprehensive understanding of ecosystem functionings, as it complements existing taxonomic findings and integrates information about the functional aspects of diverse ecosystems. [ABSTRACT FROM AUTHOR]

The influence of diet and host specificity on the fecal microbiome of three adult dragonfly species, Pseudothemis zonata, Orthetrum lineostigma, and Orthetrum melania, was investigated. The fecal bacterial communities were analyzed using 16S rRNA gene sequencing, and stable isotope analysis was used to investigate their food sources. The results showed significant differences in the composition of fecal bacterial communities among the three species, with host specificity potentially playing a more important role than diet. The dominant phyla in the fecal bacterial communities of all three species were Firmicutes, Proteobacteria, and Bacteroidetes. The operational taxonomic units (OTUs), Shannon index, and phylogenetic diversity index were not significantly different among the three species, indicating that there were no major differences in the diversity of the fecal bacterial communities. The stable isotope analysis showed that the food sources were similar among the three species, being primarily small insects found near the aquatic habitats. However, the fecal bacterial communities of two closely related species, O. lineostigma and O. melania, were different despite their similar food sources. In contrast, the fecal bacterial communities of O. lineostigma and P. zonata were similar, despite the different food sources of these two species. Our findings suggest that host specificity and diet can influence the composition of the intestinal microbiome in these insects, but the degree of influence may depend on the specific host and environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to investigate the production of chitin and chitosan from both the exuvium and whole body of mealworm (Tenebrio molitor) larvae. Chitin from the exuvium and whole body of T. molitor larvae was chemically extracted with acid and alkali solutions to achieve demineralization (DM) and deproteinization (DP), respectively. The average DM (%) and DP (%) on a dry weight (DW) basis was 32.56 and 73.16% from larval exuvium, and 41.68 and 91.53% from whole body, respectively. To obtain chitosan, chitin particles from the exuvium and whole body of T. molitor larva were heated at various temperatures in different concentrations of NaOH. Average chitin yields were 18.01% and 4.92% of DW from the exuvium and whole body, respectively. The relative average yield of chitosan from whole body was 3.65% of DW. On average, over 90% of chitosan derived from whole body was deacetylated. The viscosity of chitosan from whole body was ranged from 48.0 cP to 54.0 cP. The chitin content of dry and wet byproducts from whole body were 17.32% and 16.94% respectively, compared to dry weight. The chitosan contents of byproducts on a DW basis were 14.48% in dry and 13.07% in wet byproduct. These results indicate that the exuvium and whole body of T. molitor larva may serve as a source of chitin and chitosan for use in domestic animal feed. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, specimens of Dendrolimus superans collected from South Korea suggest the presence of D. sibiricus, instead of D. superans. Comparisons of the wing morphology, female and male genitalia, 3′‐end region of the cytochrome c oxidase I (COI) gene sequence, and internal transcribed spacer (ITS) 2 sequence of the Korean specimens with those of the D. superans specimens from Japan consistently supported the presence of D. sibiricus in South Korea. Phylogenetic analyses of the concatenated sequences of COI and ITS2 from the available sequence types of D. sibiricus and D. superans, along with South Korean specimens, were conducted using the Bayesian inference (BI) and maximum likelihood (ML) methods. These phylogenetic analyses placed the South Korean specimens with the Russian D. sibiricus as an inclusive group, excluding the Japanese D. superans, indicating the distribution of D. sibiricus in South Korea. Nevertheless, D. superans formed a distinct group only by BI analysis (Bayesian posterior probabilities = 0.89), whereas D. sibiricus, including the South Korean samples, formed a distinct group only by the ML analysis (99%), suggesting a low genetic divergence between the two species. [ABSTRACT FROM AUTHOR]

We sequenced mitochondrial genome (mitogenome) of the wild silkmoth, Saturnia boisduvalii (Lepidoptera: Saturniidae), which occurs in mainland Korea, and compared it with other species in Bombycoidea to characterize the genomic evolution of the superfamily. We found that the composition and arrangement of genes in the 15,257-bp S. boisduvalii genome are typical of the majority of Lepidoptera, and the genome is biased toward A/T nucleotides, as previously reported. Comparison of individual gene divergence among bombycoid species showed that ND6 was most variable ( p-distance = 0.21), whereas COI and COII were most conserved, indicating that of all the protein-coding genes (PCGs) ND6 appear to have evolved most rapidly. Thus, other PCGs beside COI are potential alternative markers, where scrutinized discrimination among species is required. [ABSTRACT FROM AUTHOR]

Chitin and chitosan were extracted from all specimens of Type I and II two-spotted field crickets ( Gryllus bimaculatus) following chemical treatment with an acid and alkali. For chitin extraction, 2 N HCl and 1.25 N NaOH solutions were used to achieve demineralization and deproteinization, respectively. For chitosan extraction, 50 % NaOH ( w/ v) and 50 % NaOH ( w/w) solutions were used to achieve deacetylation. Chitosan yielded from adult exoskeletons of G. bimaculatus in Test A of Type I was 1.76 and 8.40 % on a fresh weight (FW) and dry weight (DW) basis, respectively, after treatment with 50 % NaOH ( w/ v) at 95°C for 3 h. Furthermore, the chitosan yielded in Test D of Type II was 1.79 and 7.06 % on FW and DW basis, respectively, after treatment with 50 % NaOH ( w/w) at 105°C for 3 h. The average yield of chitin and chitosan was 2.42 and 1.65 % on a FW basis, and 10.91 and 7.50 % on DW basis, respectively. The deacetylation (%) of chitosan extracted from adult exoskeletons in Tests A, B, C1, C2, D1, and D2 were 81.2 %, 14.5 %, 19.6 %, 90.7 %, 17.1 %, and 95.5 %, respectively. The viscosities of the chitosans extracted from adult exoskeletons in Tests A, C2, and D2 were 32.0, 21.6, and 62.4 cP (centi Poise), respectively. The molecular weight of chitosan from adult exoskeletons of G. bimaculatus was 308.3 kDa. Our results indicate that adult exoskeletons of G. bimaculatus could be used as a source of chitin and chitosan for use as functional additives in industrial animal feeds. [ABSTRACT FROM AUTHOR]

All stages of the life cycle of Helicoverpa assulta were irradiated with X-rays to determine the inhibitory dose for development and reproduction to serve as a quarantine treatment. The 100-Gy dose was effective for irradiation of eggs and larvae, and the 200-Gy dose was effective for pupae and mixed-sex adults. When either adult males or females were irradiated, however, 500 Gy was required to prevent the F1 eggs from hatching, and thus single-sex adults required much higher doses of X-ray irradiation. To gather confirmatory data applicable to phytosanitary quarantine regulations, pupae-the immature stage most resistant to X-ray irradiation-were placed inside paprika in boxes for exportation and were irradiated with 300 Gy as a small-scale confirmatory test. The dose given to 1,007 individual pupae resulted in 12.62 % survival, and 1.79 % of pupae emerged as normal adults; however, these adults produced only a few eggs that did not hatch, suggesting that a minimum dose of 300 Gy of X-ray irradiation will provide quarantine security for immature H. assulta in paprika exports. [ABSTRACT FROM AUTHOR]

We sequenced the complete mitochondrial genome (mitogenome) of the black-tailed hornet, Vespa ducalis (Hymenoptera: Vespidae). The genome was 15,779-bp long and contained typical sets of genes [13 protein-coding genes (PCGs), 22 tRNAs, and 2 rRNAs]. The V. ducalis A + T-rich region was 166-bp long and was the shortest of all sequenced Vespoidea genomes, including Vespa. The genome was highly biased toward A/T nucleotides-80.1 % in the whole genome, 77.8 % in PCGs, 83.4-85.6 % in RNAs, and 92.8 % in the A + T-rich region. These values are well within the typical range for genes and regions of Vespoidea mitogenomes. Start and stop codons in several Vespa species-including V. ducalis-were diversified, despite these species belonging to the same genus. In comparison with the ancestral mitogenomes, Vespa mitogenomes-including that of V. ducalis-showed substantial gene rearrangement; however, we detected no gene rearrangement among Vespa species. We conducted phylogenetic reconstruction based on concatenated sequences of 13 PCGs and two rRNAs (12,755 bp) in available species of Vespoidea-21 species in six subfamilies in two families (Vespidae and Formicidae). The Bayesian inference and maximum likelihood (ML) methods revealed that each family formed strong monophyletic groups [Bayesian posterior probability (BPP) = 1; ML, 100 %]. Moreover, V. ducalis and V. mandarinia formed a strong sister group (BPP = 1; ML, 94 %). [ABSTRACT FROM AUTHOR]

Chitins and chitosans are some of the most abundant natural polysaccharide materials, and are used to increase innate immune response and disease resistance in humans and animals. In this work, chitin and chitosan from housefly, Musca domestica, pupa shells were obtained by treatment with HCl and NaOH. For chitin extraction, 2 N HCl and 1.25 N NaOH solutions were used to achieve decalcification and deproteinization, respectively. For chitosan extraction, 50% NaOH solution was used to achieve deacetylation. The yields of chitin and chitosan from pupa shells of M. domestica were 8.02% and 5.87%, respectively. The deacetylations of chitosan (from chitin C1 and C2) were 89.76% and 92.39%, respectively, after the first alkali treatment with 50% NaOH (w/w) solution at 105 °C for 3 h and 5 h, respectively. The viscosities of the chitosans (from chitin C1 and C2) were 33.6 and 19.2 cP, respectively. [ABSTRACT FROM AUTHOR]

In the present study, we determined that specimens of Kentrochrysalis consimilis collected from South Korea were K. streckeri, rather than K. consimilis, based on morphology, DNA barcodes and nuclear elongation factor 1 alpha ( EF-1α) sequences. The major morphological differences between K. streckeri and K. consimilis include the shape of forewing and hind-wing pattern elements and male and female genitalia. The DNA barcode analysis of the South Korean specimens and the Russia-originated K. streckeri showed a maximum sequence divergence of only 0.659% (4 bp), whereas that of the South Korean specimens and Japan-originated K. consimilis showed a minimum sequence divergence of 2.965% (18 bp), indicating that the Korean specimens are, in fact, K. streckeri and not K. consimilis. Phylogenetic analyses both by Bayesian inference and maximum likelihood methods strongly clustered the South Korean specimens and Russian K. streckeri into one group, excluding K. consimilis. The EF-1α-based sequence and phylogenetic analyses of the two species also supported data from the DNA barcode, indicating the distribution of K. streckeri in South Korea, instead of K. consimilis. [ABSTRACT FROM AUTHOR]

Traditionally, many irrigation ponds supplied water to paddy fields, but most of these ponds have disappeared through improvements in irrigation systems. The aim of this study was to assess the ecological functions (especially biodiversity conservation) of irrigation ponds by using benthic macroinvertebrates that inhabit paddy fields. This study was conducted in Hwaseong-si, Yesan-gun, Hongseong-gun, Uljin-gun and Damyang-gun, Korea. Benthic macroinvertebrates were collected using a quadrat sampler from August to September for three years (2010-2012) in paddy fields with and without an irrigation pond. In the comparisons between two paddy field types (paddy fields with and without an irrigation pond) for species richness and densities of benthic macroinvertebrates, the species richness and densities were higher in the paddy fields with a pond than in the paddy fields without a pond ( P < 0.001). Biodiversity enhancement effect degree ( BEED) of the irrigation pond showed positive values in all survey regions. There were no significant differences among the survey regions. BEED showed positive values in all taxonomic groups (excluding Crustacea) and were not significantly different among taxonomic groups. The BEED values for non-insects, passive dispersers, were relatively higher than for insects, active dispersers. The results indicate that BEED is related to the dispersal abilities of each taxonomic group and an irrigation pond increases biodiversity in a paddy field in all regions. Therefore, the irrigation pond is one method that can be immediately applied in paddy fields in order to improve the biodiversity of agricultural ecosystems. [ABSTRACT FROM AUTHOR]

Granite-derived soils are widespread in the farmland of Korea in general. In contrast, Jeju Island has mainly volcanic ash soils. Soils and weather condition in Jeju Island created a unique agricultural system. We identified the features of ground-dwelling insects in farmlands of Jeju Island. This study was conducted in four areas ( Samdal-ri and Susan-ri in Seogwipo city, and Dongmyeong-ri and Suwon-ri in Jeju city) in Jeju Island, Korea. Field surveys were carried out twice in summer ( June) and autumn ( September) in 2013. Ground-dwelling insects were sampled quantitatively by using pitfall traps. As a result, in total 3322 individuals, 137 species, 48 families and 8 orders were investigated in farmlands of Jeju Island. Especially, members of Coleoptera and Hymenoptera accounted for a large proportion of ground-dwelling insect communities. The numbers of species and individuals for major taxonomic groups showed significant regional and seasonal differences. This study implied that the seasonal and regional differences of ground-dwelling insect communities were affected by surrounding land use patterns, life history patterns of each taxonomic group and farmland management. [ABSTRACT FROM AUTHOR]

The spotted-wing drosophila ( SWD), D rosophila suzukii ( Diptera: Drosophilidae), originally distributed across a few Asian countries including South Korea, has invaded North America and Europe but is absent from Australia. In order to export the South Korean grape cultivar Campbell Early to Australia, its potential to serve as an oviposition and development medium for SWD must first be determined. In this study, we determined the oviposition and development potential of SWD on Campbell Early, after elucidating the SWD life cycle and establishing an artificial diet-based mass-culturing system. An investigation of the life cycle under five temperature regimes (16, 19, 22, 25 and 28° C) showed that the durations of the egg, larval and adult stages were shortened when temperature was increased from 16, 19, 22, 25 and 28° C, but pupal duration was shortest at 25° C and extended again at 28° C. A test of oviposition and development potential of SWD on Campbell Early grape clusters showed oviposition of 30.8 ± 6.8 eggs per cluster of injured grapes and 157.7 ± 16.2 eggs on a culture dish of artificial diet. However, in a similar experiment using uninjured grape clusters, only a single egg was deposited on the grape skin, which soon dried. In light of these results, newly harvested grapes left at vineyards during daily harvests are unlikely to serve as an oviposition and development medium for SWD, as long as the grapes remain uninjured. [ABSTRACT FROM AUTHOR]

In this study, we sequenced both two mitochondrial genes ( COI and 16 S r RNA) and nuclear genes (28 S r RNA and elongation factor-1α) from 71 species of Odonata that represent 7 superfamilies in 3 suborders. Phylogenetic testing for each two concatenated gene sequences based on function (ribosomal vs protein-coding genes) and origin (mitochondrial vs nuclear genes) proved limited resolution. Thus, four concatenated sequences were utilized to test the previous phylogenetic hypotheses of higher taxa of Odonata via Bayesian inference ( BI) and maximum likelihood ( ML) algorithms, along with the data partition by the BI method. As a result, three slightly different topologies were obtained, but the BI tree without partition was slightly better supported by the topological test. This topology supported the suborders Anisoptera and Zygoptera each being a monophyly, and the close relationship of Anisozygoptera to Anisoptera. All the families represented by multiple taxa in both Anisoptera and Zygoptera were consistently revealed to each be a monophyly with the highest nodal support. Unlike consistent and robust familial relationships in Zygoptera those of Anisoptera were partially unresolved, presenting the following relationships: (((( Libellulidae + Corduliidae) + Macromiidae) + Gomphidae + Aeshnidae) + Anisozygoptera) + ((( Coenagrionidae + Platycnemdidae) + Calopterygidae) + Lestidae). The subfamily Sympetrinae, represented by three genera in the anisopteran family Libellulidae, was not monophyletic, dividing Crocothemis and Deielia in one group together with other subfamilies and Sympetrum in another independent group. [ABSTRACT FROM AUTHOR]

Hipparchia autonoe belongs to the family Nymphalidae ( Lepidoptera) and is designated as an endangered insect and national monument in Korea. It only inhabits a very restricted area on Mt. Halla but is widely distributed in several Asian countries including Mongolia. A previous study conducted to understand the genetic relationship between Mt. Halla and Mongolian H. autonoe for conservation purposes suffered from a limited number of samples. Therefore, we sequenced the DNA barcode region of an additional 36 H. autonoe individuals, combined them with previous data from 19 individuals, and performed phylogenetic and population genetic analyses. Furthermore, the internal transcribed spacer 2 ( ITS2) region was also sequenced from the 36 samples as a nuclear DNA marker. The existence of independent haplotypes, sequence types, and significant FST estimates ( P < 0.05) between Mt. Halla and Mongolian populations indicated hampered gene flow between the populations. Nevertheless, an absence of a reciprocal monophyletic group in Mt. Halla and Mongolian populations by cytochrome oxidase subunit I gene- and ITS2-based phylogeny suggests that the genetic isolation of the Mt. Halla population from the Mongolian populations seemed not large enough to consider them independent genetic entities. [ABSTRACT FROM AUTHOR]

The species status of O eneis urda ( Eversmann) and O . mongolica ( Oberthür) has been argued based on morphological characters. Reexamination of their major morphological characters has shown a slight differentiation in the two species. Sequences of three mitochondrial genes ( COI, ND6, and ND1) and one nuclear region (internal transcribed spacer 2, ITS2) from two O . urda populations ( Yangyang and Mt. Hanla) and one O . mongolica population ( Uljin) were performed for phylogenetic and population genetic inferences. Sharing of identical sequences in the ND6 gene and ITS2, minimal sequence divergence in the COI and ND1 genes, and phylogenetically undividable sequence types in all mitochondrial genes and ITS2 suggest genetic continuity between the two species. Nevertheless, significant FST estimates ( P < 0.05) were found for the COI gene in comparisons between Yangyang ( O . urda) and Uljin ( O . mongolica), between Yangyang ( O . urda) and Mt. Hanla ( O . urda), and between Uljin ( O . mongolica) and Mt. Hanla ( O . urda) populations. These FST estimates, along with other gene-based analyses collectively suggest isolation of the two species at some point in the past, but incomplete separation between the two species on the mainland ( Yangyang and Uljin) and biogeographically forced isolation of the O . urda population on Mt. Hanla collectively appear to complicate species status of these two species that were once further clearly separated. [ABSTRACT FROM AUTHOR]