We'd like to understand how you use our websites in order to improve them. Register your interest. We tested three artificial diets for rearing larvae of Chrysoperla externa Hagen Neuroptera: Chrysopidae , aiming at reducing the production costs of this predator. Two of the diets come from studies with other species of lacewings, and the third is a modification described in this paper. All diets were based on animal protein and were supplied to 2nd and 3rd instar larvae, whereas 1st instar larvae received eggs of Anagasta kuehniella Zeller Lepidoptera: Pyralidae.
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This work aimed to elucidate the distribution of Chrysoperla externa haplotypes and investigate whether it exhibits structure based on genetic composition as opposed to geographic location.
The genetic diversity of C. This was reflected in the network grouping. Bayesian inference showed that haplotype distribution may have its origins in C. The evolutionary history of C. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: All relevant data are within the paper and its Supporting Information files.
Competing interests: The authors have declared that no competing interests exist. Green lacewings are insects of the Chrysopidae, a family of 1, species and subspecies distributed among 82 genera [ 1 ]. The last named is one of the most common lacewing species in the Americas and can be found from the southern USA to Argentina [ 2 ].
Studies of the biology of C. The genetic variation and degree of population structure of C. The specimens of C. High levels of diversity were observed for both markers, with the highest values found in municipalities having the largest areas of native vegetation [ 5 ]. A further 12 populations and specimens were studied in SP, revealing high genetic diversity and lack of geographic structure, suggesting that C.
The most comprehensive study of C. The results showed population expansion in agro-ecosystems, whereas populations in the native environment remained stable over time. Analysis showed significant genetic structure among the sampled groups, which, combined with its within-group absence, corroborated group identities [ 7 ]. Although the studies carried out to date have analyzed a sufficient number of specimens for population studies of C. Research using the mitochondrial marker 16S rRNA gene, as proposed in this study, provides information on population history on a wider time scale than do the COI gene and ISSR markers previously used [ 4 — 7 ].
The goal of this study was to reveal the genetic structure of C. This study gathers new specimens of C. All the specimens were collected in open areas and on agrosystems borders. The specimens were stored in absolute ethanol and identified based on external morphological characteristics according to Brooks and Barnard [ 8 ] by Dr.
The products were sequenced using the same primers and amplification conditions. The sequences were read in Chromas Lite v. Descriptive analyses were performed using DnaSP v. Nucleotide composition was calculated by MEGA v. A haplotype network was built using TCS v. The presence of population structure was tested for the genes separately using a Bayesian approach with Structure v. Several runs were realized without replicates to estimate the probable K value clusters based on the ln Pr X K value.
Twenty-five independent runs were carried out for each K value, ranging from 1 to 8 for the COI gene and 1 to 5 for the 16S gene. For each run, 10, iterations were carried out after a burn-in of 10, iterations. The assumed parameters for both genes were "no model admixture" because they were haploid mitochondrial genes, and "all frequencies correlated" since the sequences had high similarity [ 17 ].
To detect the number of genetically homogeneous groups K that best fit the data, we used Evanno implemented [ 20 ] in the Structure Harvester website [ 21 ]. We performed million MCMC simulations and sampled every steps, under the lognormal relaxed clock model and a constant-size coalescent tree prior. The priors were checked in Tracer v. This was viewed and edited in FigTree v. We obtained sequences of bp each for the COI gene and haplotypes S2 Table , and sequences of bp each for the 16S gene and 58 haplotypes S3 Table.
The concatenated data generated sequences of 1, bp each, which presented an average nucleotide composition of One hundred fifty-eight polymorphic sites S were obtained, resulting in haplotypes h S4 Table and an average haplotype diversity Hd of 0. The genetic structure was used to investigate the species C. Initially, AMOVA was used to test the structure by locality, considering all populations as a single group.
The haplotype network for both genes showed well-defined groups. All groups contained specimens from different localities; hence grouping based on geographic distribution was not observed S1 — S3 Tables. The distribution of haplotypes was coincident in Group 4, in which the specimens were isolated from the other groups with respect to both genes S1 Fig and S2 Fig.
The specimens were not coincident in other groups; specimens belonging to a group in the COI gene appeared in different groups in the 16S gene, and vice-versa S1 Fig and S2 Fig. Square represent the ancestral haplotypes. The size of circle reflects the frequency of the haplotypes in the sample. Small black dots denote missing intermediate haplotypes. Square represents the ancestral haplotype. Small black circles denote missing intermediate haplotypes.
The population pairwise F ST s also presented high values, demonstrating that Group 4 did not skew this structure Table 1.
Structure analysis was used to visualize the genetic similarity among individuals and test the presence of population structure. For the COI gene, individuals were grouped into six clusters Figs 1 and 3 , which were interpreted as mutational steps occurring from an ancestral haplotype not present in the analysis. Group 2 presented the same clusters as Groups 1 and 3, but in different probability.
Group 4 appeared separately, similar to results of TCS, indicating genetic composition distinct from other groups. The 16S gene was separated into two clusters, with Groups 1, 3, and 4 in a cluster and Groups 2 and 5 in another Figs 2 and 4. Colors represent clusters K , interpreted as mutational steps from an ancestral haplotype not present in the analysis.
Bayesian inference analysis was performed to obtain the probable relationship between haplotypes of C. The clade comprising Groups 1, 2, 3, and 5 showed internal clades that were not monophyletic, while the Group 4 clade was monophyletic and showed more recent divergence.
The node type represents Bayesian posterior probability. Based on the Bayesian inference separation, the neutrality test was conducted for Group 4 separately from the remaining groups. Our results demonstrated that C. Almost all the COI haplotypes and 58 16S haplotypes were found in all sampled locations. The AMOVA demonstrated that haplotype differences among locations were not significant, showing that the distances between sampling sites, in Brazil and Paraguay, did not act as a barrier, and produced no geographic differentiation.
This would be a necessary premise for the phylogeographic inference test, which could assess the haplotype and geographic association [ 33 ]. This did not occur in the present or in previous studies of C. Therefore, we used the groups formed in the network to assess by AMOVA the relationship between the distinct haplotypic groups, and the analysis revealed significant differences in both analyzed genes. Hence, the haplotypes showed genetic differences sufficient to be allocated into groups, and that different haplotypic groups coexisted in a location.
Bayesian inference performed on the concatenated data suggested that there was initially a divergence of C. This clear separation of haplotypes into clades of C. The clade with the most recent diversification was composed exclusively of individuals from Group 4 in both gene haplotype networks.
In both analyzed genes, these 34 individuals showed greater similarity to one another than to the other groups. In the structure analysis of the COI gene using Structure Fig 3 , the union of Groups 1, 2, and 3 indicated by the presence of at least one cluster in common, and the segregation of Group 4, reinforced the results of the Bayesian analysis Fig 5 for the divergence into two clades.
For 16S , the structure analysis showed the separation into only two clusters Fig 4 with Group 4 remaining associated with Groups 1 and 3.
This can be attributed to the fact that the 16S gene is conserved and non-coding, so that the primary difference observed between the two clusters is the insertion of one or two bases at positions and S1 Supporting Information. Thus, the phylogenetic information that shows the initial divergence may have been diluted in the structure analysis, since it does not include the ancestral state present in the outgroup [ 44 , 45 ].
The population expansion followed by diversification of haplotypes can be inferred by the star-like network topology of both genes, as well as by the neutrality tests. The networks displayed two more frequent haplotypes that were considered ancestral S2 Table and S3 Table from which many haplotypes were derived, suggesting that most of these haplotypes emerged later [ 46 ]. The results of Tajima's D and Fu's F S neutrality tests were negative, indicating an excess of rare alleles within the population, which may suggest population expansion [ 47 , 48 ].
These results suggest that the evolutionary history of C. However, it is possible to infer that this pattern found for C. Thus, this agricultural practice may have promoted homogenization in the populations trough the introduction of haplotypes from other regions with distinct genetic characteristics, covering up a possible regional differentiation.
As a result of this introduction, it is currently observed a pattern of co-existence of multiple ancestral haplotypes in the same place, but belonging to groups excessively genetically distinct to be sharing the same area of occurrence in a biogeographic point of view, and thus indicating that these haplotypes have had an allopatric differentiation.
Therefore, it is possible that the earlier geographical history of C. The size of circles reflects the frequency of the haplotypes in the sample. Haplotype names correspond to names in S1 Table. Small circles denote missing intermediate haplotypes. Positions from 1 to are for the COI gene, and from to are for the 16S gene. Identification code ID of haplotypes for COI gene; number of specimens containing each haplotype; GenBank accession number; Chrysoperla externa voucher number.
Identification code ID of haplotypes for 16S gene; number of specimens containing each haplotype; GenBank accession number; Chrysoperla externa voucher number.
Identification code ID of haplotypes for concatenated data COI and 16S genes ; number of specimens containing each haplotype; Chrysoperla externa voucher number. We thank to deceased Prof. Browse Subject Areas? Click through the PLOS taxonomy to find articles in your field. Abstract This work aimed to elucidate the distribution of Chrysoperla externa haplotypes and investigate whether it exhibits structure based on genetic composition as opposed to geographic location.
Introduction Green lacewings are insects of the Chrysopidae, a family of 1, species and subspecies distributed among 82 genera [ 1 ]. Materials and methods Biological materials This study gathers new specimens of C.
Revista de la Sociedad Entomológica Argentina
Chrysoperla externa Neuroptera: Chrysopidae and Utetheisa ornatrix Lepidoptera: Arctiidae on organically grown Crotalaria juncea Fabaceae. Chrysoperla externa Neuroptera: Chrysopidae e Utetheisa ornatrix Lepidoptera: Arctiidae sobre Crotalaria juncea Fabaceae cultivada organicamente. Costa, M. I ; Tavares, W.
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This work aimed to elucidate the distribution of Chrysoperla externa haplotypes and investigate whether it exhibits structure based on genetic composition as opposed to geographic location. The genetic diversity of C. This was reflected in the network grouping. Bayesian inference showed that haplotype distribution may have its origins in C.