Highest Genetic Distance Research Articles

Molecular identification, genetic diversity, and secondary structure predictions of Physalis species using ITS2 DNA barcoding

BackgroundThe genus Physalis belongs to the Solanaceae family and has different species with important nutritional and medicinal values. Species within this genus have limited morphological differences, a characteristic that hinders accurate identification, safe utilization and genetic conservation of promising genotypes. In addition, to prevent the perceived loss of Physalis diversity due to habitat destruction, species delimitation needs attention. In this study, we used the sequence and structural information of the internal transcribed spacer 2 (ITS2) barcode to efficiently identify and discriminate Physalis species from a collection of 34 Physalis accessions.MethodologyPhysalis plant samples were collected from eight Counties in Kenya based on the availability of the germplasm. The voucher specimens were identified using the botanical taxonomy method and were deposited in the University of Nairobi herbarium. A total of 34 Physalis accessions were identified and accessed for diversity based on the ITS2 barcode region. The sequence similarity of the ITS2 genes was analyzed through the Basic Local Alignment Search Tool (BLAST), the nearest Kimura-2-parameter (K2P) genetic distances were calculated and a phylogenetic tree was constructed using the Bayesian inference (BI) method in MrBayes 3.2.7a software. The differences in the ITS2 secondary structure between the species were analyzed.ResultsThe success rate of PCR amplification and sequencing was 75% and 67%, respectively. The analyzed ITS2 sequences displayed significant inter-specific divergences, clear DNA barcoding gaps and high species identification efficiency. Based on the constructed phylogenetic tree, three Physalis species (Physalis peruviana, Physalis purpurea and Physalis cordata) were identified and were clustered in a homogenized distribution. High genetic diversity (0.36923) and genetic distance (0.703) were observed between Physalis peruviana and Physalis cordata. The highest genetic nucleotide diversity (0.26324) and distance (0.46) within species was obtained for Physalis peruviana. The differences in the secondary structures generated from this study discriminated between the Physalis species.ConclusionsOur study demonstrated that ITS2 is a potential DNA barcode for effective identification and discrimination of Physalis species. The results of this study provide insights into the scientific basis of species identification, safe utilization, genetic conservation and future breeding strategies for this important nutritional and medicinal plant species.

Genetic analyses of advanced breeding lines of rice for yield-attributing traits and salinity stress tolerance

The development of advanced rice breeding lines and their evaluation for yield-attributes and salinity stress tolerance offers a significant opportunity to identify high-yielding salt-tolerant genotypes exhibiting desired traits. The present study aimed to examine the morpho-genetic variability of thirty-six advanced breeding lines of rice, with a focus on features that contribute to yield and salinity stress tolerance. Three replications of a randomized complete block design were used in the first experiment. Significant variability was observed among the lines for the studied quantitative traits. Based on yield attributing traits, the advanced breeding lines viz., Line 10, Line 21, Line 22, Line 23, Line 24 and Line 25 showed better performances in terms of earliness and yield. In yield-related variables such as the number of effective tillers per plant, plant height, and grain yield per plant exhibited high heritability coupled with high genetic advance as percentage of mean. The results of PCA biplot showed that the PC1 and PC2 accounted for the greatest variability of advanced Line 10, Line 11, Line 18, Line 21, Line 22, Line 23, Line 24, Line 25, Nerica 10, Begunipata, and Binadhan-14 with significant influence of the studied traits. Cluster analysis reflected that the high-yielding genotypes were placed in cluster II and VI. Highest genetic distance was observed among the genotypes of cluster III and cluster VI. In the second experiment, four advanced breeding lines along with salt tolerant and susceptible checks were assessed for salinity tolerance at the reproductive stage. The plants were cultivated in a large plastic-tub filled with field soil. During the late booting stage, saline (EC=10 dS/m) irrigation water was applied to the plants and continued for three weeks. While Lines 10 and 12 demonstrated a reduced decline, salt stress caused a significant loss in yield and yield-attributing characteristics in all genotypes. Line 10 and Line 12 which showed a reasonable degree of salt tolerance as well as early maturity were placed in the respective quadrant of the biplot. Stress tolerance indices also reflecting the better salt tolerance phenomena of the advanced Line 10 and Line 12. Considering all of the traits, Line 10 and Line12 could be selected as desired advanced rice lines for the development of early, high-yielding and salt tolerant rice varieties.

Genetic Diversity and Relationship of Native Phalaenopsis Orchids: A Case Study of Indonesian Archipelago

The native Phalaenopsis is valuable germplasm for future orchid breeding programs and for its conservation because it provides many beneficial traits or genes. This study aimed to determine and analyze the molecular diversity and phylogeny of Indonesian native Phalaenopsis by a DNA barcoding (matK) marker. A total of 19 samples of Phalaenopsis orchids were used in this study. All leaf samples of orchid were extracted and purified using a commercial DNA isolation kit from Geneaid Biotech Ltd., Taiwan (GP100). The DNAs were then amplified by specific matK primers: Forward (5’-CGTACAGTACTTTTGTGTTTACGAG-3’) and Reverse (5’-ACCCAGTCCATCTGGAAATCTTGGTTC-3’). The DNA targets or products (matK) were purified and sequenced by the Sanger-bidirectional method at 1st Base Ltd., Malaysia. Before further analysis, the matK sequences of Phalaenopsis were edited, reconstructed, and aligned with the assistance of Clustal W in the MEGA 11 software. Its genetic diversity was determined using the nucleotide diversity index (π%), and the phylogenetic analysis was performed using the maximum likelihood (ML) method with a statistical bootstrap. The phylogenetic relationship was also assessed using principal component analysis (PCA). Based on this marker, the native Phalaenopsis has a high genetic diversity (π% = 1.70). In addition, the phylogenetic analysis revealed that this germplasm was separated into seven clades, where P. pantherina has the closest relation to P. cornu-cervi and P. gigantea. Conversely, the highest genetic distance was to P. amabilis from South Kalimantan and to P. celebensis from Sulawesi, at a coefficient divergence of 0.084. Our findings provide an essential foundation for supporting future orchid breeding practices, including conservation, on local and global scales.

GENETIC DISTANCE AND IDENTITY AT IGF-1 GENE LOCUS OF SOME INDIGENOUS CATTLE BREEDS IN NIGERIA

An experiment was conducted to determine the genetic distance and identity at insulin-like growth factor 1 (IGF-1) gene locus in some indigenous cattle breeds in Nigeria. One (1) Local Government Area (LGA) each from Adamawa, Taraba, Gombe and Sokoto States was purposively selected which include Mubi North, Yorro, Balanga, and Wurno Local Government Areas, respectively. The snowball method was used to sample (96) cattle consisting of (24) Adamawa Gudali, (24) Sokoto Gudali, (24) Bunaji and (24) Rahaji cattle from pastoralists in many communities of the LGAs. Blood samples were collected from the animals through jugular venepuncture. DNA extraction was done using Zymo Quick DNA™ Mini prep kit. NanoDrop 1000 spectrophotometer was used for the determination of DNA quality and quantity using DNA purification kit. Genetic distances among the breeds of cattle were calculated using distance measures with the aid of Gen AIEx software package. The highest level of genetic distance estimate was observed between Rahaji and Bunaji cattle breeds (0.085) while the closest genetic distance (0.001) was observed between Sokoto Gudali and Bunaji. The highest genetic identities were recorded between Sokoto Gudali and Bunaji (0.999) cattle breeds whereas the closest matrix of genetic identity (0.904) was recorded between Rahaji and Sokoto Gudali cattle. Cluster analysis using UPMGA revealed that Bunaji and Sokoto Gudali cattle formed the first cluster which is separate from Adamawa, which formed the second cluster. Rahaji cattle formed the third cluster, which is far and distant from the first and second clusters at IGF-1 gene locus. Rahaji cattle had the longest genetic distance with other three breeds of cattle. High genetic distance and identity existed among some indigenous breeds of cattle studied.

ASSESSMENT OF GENETIC DISTANCE AND SIMILARITIES AMONG INDIGENOUS CHICKEN POPULATIONS IN KANO-STATE, NIGERIA

The study was conducted to examine the genetic diversity of three populations of indigenous chicken in Kano State, Nigeria. A total of 249 matured free-ranging chickens between the ages of 6-24 months were sampled. Three genetic groups of indigenous chicken were identified in the study location which includes normal feathered (N), frizzle feathered (Ff) and naked neck (Na) and 2ml. of blood samples obtained from & birds per genotype were used for the study. Genomic DNA was extracted individually from the sampled blood using Quick DNA Kits (©Zymo-Spin Research Kit). Five microsatellite markers were used for genotyping. Genetics Analysis in Excel Software (GenAlEX sofivare version 6.5) was used for band analysis. The result showed relatively high genetic diversity which is essential for the populations. The chicken populations had degrees of genetic similarity of (0.840-0.925) and genetic distance of (0.078-0.084). High genetic distance of (0.084) was observed between N and Ff. It was concluded that the populations were not isolated and the microsatellite markers used were highly informative and can be used in future studies involving chicken populations.

Mating Strategy in the Arab Horse Population Over 30 Years in Algeria

Abstract The objective of this research was to describe the variation in breeding practices in the population of Arabian horses in Algeria in relation to the population size drop observed in the 2000s, due to an increase in the cost of food and a change in interest in racing, related to the black decade. As a result, the breeders had to face two opposite constraints: enhancing reproduction to counter the population decline and preventing the loss of genetic diversity. The aim of the study was to evaluate the genetic consequences of the decisions taken over a period of 30 years, starting from 1988 to 2018. The study was based on the analyses of the stud-book and on 11 microsatellite markers in a group of 943 horses, distributed into 13 age classes. Between 2004 and 2008, the breeders purchased foreign sires and dams, allowing a relative stability in unbiased heterozygosity of about 71%, due to the high genetic distances between foreign and local horses. As these importations stopped from 2009 on, there was a decrease in allele numbers of about 20%. Moreover, from 2010 on, we observe an excess of inbreeding and an increase in genetic drift relative to the starting population, due to population size decline. From the analysis of genetic distances between local individuals, it seems that the only constraint for sires and dams allowed to mate was a null coefficient of inbreeding.

Genome-wide SNP assessment of contemporary European red deer genetic structure highlights the distinction of peripheral populations and the main admixture zones in Europe.

Genome-wide technologies open up new possibilities to clarify questions on genetic structure and phylogeographic history of taxa previously studied with microsatellite loci and mitochondrial sequences. Here, we used 736 individual red deer (Cervus elaphus) samples genotyped at 35,701 single nucleotide polymorphism loci (SNPs) to assess the population structure of the species throughout Europe. The results identified 28 populations, with higher degrees of genetic distinction in peripheral compared to mainland populations. Iberian red deer show high genetic differentiation, with lineages in Western and Central Iberia maintaining their distinctiveness, which supports separate refugial ranges within Iberia along with little recent connection between Iberian and the remaining Western European populations. The Norwegian population exhibited the lowest variability and the largest allele frequency differences from mainland European populations, compatible with a history of bottlenecks and drift during post-glacial colonization from southern refugia. Scottish populations showed high genetic distance from the mainland but high levels of diversity. Hybrid zones were found between Eastern and Western European lineages in Central Europe as well as in the Pyrenees, where red deer from France are in close contact with Iberian red deer. Anthropogenic restocking has promoted the Pyrenean contact zone, admixture events in populations on the Isle of Rum and in the Netherlands, and at least partly the admixture of the two main lineages in central-eastern Europe. Our analysis enabled detailed resolution of population structure of a large mammal widely distributed throughout Europe and contributes to resolving the evolutionary history, which can also inform conservation and management policies.

Phylogeny and genetic diversity of Echinometra sea urchin in Taiwan

ABSTRACT Four closely related Echinometra species exist in the Indo-Pacific region, but little is known about their population genetics in Taiwan, an area rich in marine biodiversity. Echinometra dominates the Douziping coral reef off Liuqiu Island, where urchin barrens are also present. To understand the relationship between Echinometra species and urchin barrens, we investigated the genetic diversity of Echinometra species in Taiwan by using a nondestructive DNA extraction method on the spines of sea urchins. Mitochondrial DNA results showed that E. sp. C is the dominant species in Taiwan, with relatively high interspecific genetic distance. The E. sp. C is the only species in Douziping, and its population is expanding in accordance with the significantly low R2 value, the significantly negative Fu’s Fs values, and mismatch distribution analysis results. Gene flow estimates between the urchin populations in Taiwan and those in the neighbouring waters of Okinawa suggested that the Kuroshio Current could play an important role in Echinometra dispersal. This implies strongly connectivity between these populations. This study reports the first case of E. sp. C-associated urchin barrens in the tropics.

Mitochondrial DNA evidence reflects high genetic divergence of Amynthas aspergillum (Oligochaeta: Megascolecidae) in southern China.

Amynthas aspergillum (Perrier, 1872), a natural resource used in traditional Chinese medicine (Guang-dilong) with high economic value, is widely distributed in forests and farmland habitats in the hilly areas of southern China. To investigate the extent of genetic differentiation and diversity in A. aspergillum, a population genetic structure study was performed on 157 samples from 75 locations in southern China using the mitochondrial genes COI, COII, 12S rRNA, 16S rRNA, and NDI. The results indicated that A. aspergillum had a high level of genetic diversity, and variation within populations was the main source of the total variation. Six deeply divergent mitochondrial clades (I-VI) were detected using both phylogenetic tree and haplotype network analyses. This finding was supported by the high Kimura two-parameter genetic distance and the pairwise fixation index value obtained based on the COI gene. No significant phylogeographic structures were observed. The widespread geographic distribution of clades II, IV, and VI suggested a recent demographic expansion based on multiple analysis results. These results include a high level of Hd and low π, star-shaped haplotype network structures with a high number of less frequent haplotypes, significantly negative neutrality test values, and a unimodal mismatch distribution pattern. The divergence time estimates and reconstruction of the ancestral area revealed that A. aspergillum originated in Guangxi Province and underwent initial intraspecific diversification in the early Pliocene to generate clade I. Then, it gradually dispersed eastward and rapidly differentiated into clades II-V during the Pleistocene. The Yunnan-Guizhou Plateau and Nanling and Wuyi Mountains might act as geographical barriers for the spread of A. aspergillum to the west and north.

DNA barcoding of common freshwater eleotrids (Gobiiformes: Eleotridae) in the Philippines, with a global comparison and notes on their conservation and management

Eleotrids, also known as gudgeons or sleeper gobies, are found mostly in freshwater and mangrove habitats of tropical and subtropical regions. Some eleotrids exhibit minimal morphological variation at the species level. In this study, DNA barcoding was used to assess the molecular diversity of common freshwater eleotrids in the Philippines in relation to other eleotrid species from other countries with available DNA sequences in public databases. A total of 422 mitochondrial DNA cytochrome c oxidase I (COI) gene sequences were analyzed: 107 of which were generated from this study, while the remaining 315 sequences were mined from Barcode of Life Data System and GenBank. Both the neighbor-joining and maximum likelihood trees constructed based on the COI sequences clustered most of the species in concordance with their taxonomic classification. The mean Kimura 2-parameter genetic distances within species and genera were 1.31% and 11.60%, respectively. As expected, the mean interspecific distance was higher than the mean intraspecific distance except in some species. This study revealed the presence of nine distinct eleotrid species belonging to five genera in the Philippines. These species include Giuris laglaizei, G. tolsoni, Eleotris acanthopomus, E. fusca, E. melanosoma, Belobranchus sp., Belobranchus belobranchus, Butis butis, and Ophiocara ophicephalus. This study also revealed the presence of possibly undescribed Belobranchus species in the Philippines. This undescribed Belobranchus species differs by a high percentage of genetic divergence from the other species of Belobranchus (3.00% from B. segura and 13.40% from B. belobranchus). Furthermore, high genetic distance (2.62%) was also observed between G. laglaizei species of Laguna de Bay and Mindanao. This study strongly recommends a taxonomic review of the Laguna de Bay G. laglaizei and the Philippine Belobranchus spp., as these species may harbor species complexes that require closer examination so that proper conservation and management measures can be implemented for each species.

Geographic variation in genetic composition, sexual communication and mating compatibility of the False Codling Moth, Thaumatotibia leucotreta for optimisation of area-wide control

Intraspecific variation in sex pheromones is a driver of reproductive isolation and speciation in insects. The False Codling Moth (FCM) Thaumatotibia leucotreta (Lepidoptera: Tortricidae) is a quarantine pest endemic to sub-Saharan Africa (SSA). The currently available precision control measures for FCM use female sex pheromone components to lure males into traps. However, the existing data on the composition of the female sex pheromone, especially the isomer ratios of the main pheromone component (E/Z)-8-dodecenyl acetate, are inconsistent for populations in SSA. This inconsistency led to speculation about possible reproductive isolation between geographically separated FCM populations and the potential need for local adjustment of pheromone-based FCM control tools. This, however, requires a comparative evaluation of geographic variation in FCM sexual communication and inter-population mating compatibility. We therefore investigated genetic isolation and mating compatibility between five geographically isolated FCM populations in South Africa and analysed the ratio of (E)- and (Z)-8-dodecenyl acetate in females from these populations. The five studied populations were found to form three genetically distinct groups with high genetic distances between each other. Mating compatibility tests showed that mating is possible across these groups, however, males preferred females of their own population when given choices; without a choice, males successfully mated with and transferred spermatophores to females from all other populations. The ratio of (E)- and (Z)-8-dodecenyl acetate was similar (c. 4:1) across the populations, indicating that this main female pheromone component does not cause the observed intra-population mating preferences. It remains to be investigated if qualitative/quantitative variation in other sex pheromone components influences intra-population recognition in South African FCM, providing a base for the development of regionally-specific lures for area-wide control programmes.

DNA barcoding reveals cryptic species in the sea slater Ligia italica (Crustacea, Isopoda) from Tunisia

Barcoding studies have provided significant insights into phylogenetic relationships among species belonging to the genus Ligia (Crustacea, Isopoda). Herein the diversity of the Italian sea slater Ligia italica from Tunisia is studied for the first time. Samples were collected from 18 localities in Tunisia, and the analysis included previously published sequences from Italy and Greece available in GenBank. Bayesian and Maximum Likelihood phylogenetic analyses were carried out using a fragment of the mitochondrial COI gene. Putative cryptic species were explored using the ‘barcode gap’ approach in the software ASAP. A genetic landscape shape analysis was carried out using the program Alleles in Space. The analyses revealed highly divergent and well-supported clades of L. italica dispersed across Tunisia (Clades A1 and A2), Greece (Clade B) and Italy (Clades C1 and C2). High genetic dissimilarity among clades suggested that L. italica constitute a cryptic species complex. Divergence among different L. italica lineages (Clades A, B and C) occurred around 7–4.5 Ma. The detected high genetic distances among clades did not result from atypical mitochondrial DNAs or intracellular infection by Wolbachia bacteria. The complex history of the Mediterranean Sea appears to have played a significant role in shaping the phylogeographic pattern of Ligia italica. Additional morphological and molecular studies are needed to confirm the existence of cryptic species in Ligia italica in Mediterranean.

Taxonomic identification and life cycle comparison of two populations of the monostromatic green algae Monostroma nitidum.

Monostroma nitidum, a monostromatic green algae (MGA) with high economic value, is distributed worldwide. Life cycle often serves as a fundamental criterion for taxonomic classification. Most researchers consider the life cycle of M. nitidum to involve dimorphic alternation of generations, although the possibility of a monomorphic asexual life cycle remains unclear. In this study, tufA and 18S rDNA sequences were employed as molecular markers, complemented by morphological analysis, to classify and identify MGA in two distinct habitats: Hailing Island reefs (YJ) and Naozhou Island reefs (ZJ). The results of tufA and 18S rDNA sequence analysis revealed that all samples from YJ and ZJ clustered to the same branch (M. nitidum clade) with high bootstrap support and genetic distances of less than 0.000 and 0.005, respectively. However, morphological observations indicated significant differences in the external morphology of the YJ and ZJ samples, although both initially exhibited a filament-blade form during early development. The life cycle of the ZJ samples exhibited typical dimorphic alternation of generations, whereas the YJ samples only produced biflagellate asexual gametes with negative phototaxis. Gametes of the YJ samples directly developed into new gametophytes without undergoing the sporophyte stage. Consequently, the YJ and ZJ samples were classified as monomorphic asexual and dimorphic sexual M. nitidum, respectively. These findings provide evidence supporting the monomorphic asexual life cycle of M. nitidum for the classification of MGA.

Evaluation of genetic diversity in faba bean (Vicia faba L.)

The present investigation was carried out to study inherent genetic diversity among 35 genotypes of faba bean (Vicia faba L.) using Mahalonobis D2 statistics. D2 analysis grouped studied genetypes into 16 clusters in Environment 1 (Early sowing) and 12 clusters in Environment 2 (Late sowing). The intra-cluster distance was greater in Cluster I of Environment 1 (8.48) and Cluster V of Environment 2 (7.99). While greater inter-cluster distance was observed between cluster X and XIV in Environment 1 and between cluster X and XII in Environment 2. Seed yield per plant contributed the highest towards total divergence in the present study under both environments (49.25% in Environment 1 and 28.41% in Environment 2). The genotypes RFB 14, ET226414, ET226415, HFB-1, ET226430, ET226426 and ET226417 belonging to different clusters in both environments had higher genetic distance and can be used as a parent for further hybridization program for generating the useful variability.

Molecular Identification of Neoechinorhynchus iraqensis (Acanthocephala: Neoechinorhynchidae) from Planiliza abu in Darbandikhan Lake

A total of 100 fishes belonged to Planiliza abu (Heckel, 1843) were taken from Darbandikhan Lake in Sulaimani Province, Kurdistan Region, Iraq from December 2023 to February 2024. The fish were checked for parasitic acanthocephalan. The research showed that Neoechinorhynchus iraqensis existed. In this study, 18S rDNA and DNA sequencing were used to identify N. iraqensis. The findings of the molecular analysis show that 533 bp was the PCR product of N. iraqensis and observed the smallest genetic distance with Neoechinorhynchus sp. GL-2015 (KU363972.1) and Neoechinorhynchus sp. XL-2014 (KM507363.1) was (0.025), and the highest genetic distance was recorded with Tenuisentis niloticus (MZ727194.1) was (0.194). Neighbor - Joining trees inferred for 18S rDNA showed that N. iraqensis as a separate clade in the trees, demonstrating that this species originated in Iraq. This finding indicates that the species is the same species that was morphologically identified and described for the first time in Iraq.

Genetic Variation of Foxtail Millet (Setaria italica (L.) P. Beauv.) Germplasm From Polewali Mandar West Sulawesi Based On Morphological Characters

Foxtail millet (Setaria italica (L.) P. Beauv.) is a cereal crop that has long been domesticated worldwide and has been adopted as a model crop to provide a deeper understanding of plant biology. This plant has long been a mainstay of indigenous Indonesian people, especially in Polewali Mandar, West Sulawesi Province. This study aims to evaluate the genetic variation of foxtail millet germplasm from Polewali Mandar, West Sulawesi based on morphological characters. Three germplasm populations were collected from Polewali Mandar to assess genetic variation in millet germplasm. The observations of morphological traits were carried out based on the IBPGR of Setaria italica. Genetic variation in foxtail millet populations was measured using 28 morphological traits with nine qualitative and 19 quantitative characters. The research showed that seed color, stem diameter, plant height, panicle stalk length, and panicle stalk diameter had diverse variations. Cluster analysis of morphological characters using the UPGMA method shows a similarity coefficient ranging from 0.15-0.2. At a genetic similarity coefficient of 0.2, the three populations were divided into Cluster A and Cluster B. Cluster A consists of two populations (Minna' and Lasse'). In contrast, Cluster B consists of one population (Bulawang). The millet population SLB.C.3-SLB.A.1 has the highest genetic distance and is a potential candidate to be selected as a parent cross to produce higher het-erosis. Intensification of millet plant breeding programs is expected to increase the genetic basis for determining specific characteristics.

Deciphering Genetic Diversity in Advanced Wheat Lines (Triticum aestivum L.) for Yield and Other Yield Contributing Traits Across the Locations

Twenty advanced wheat genotypes were evaluated for yield and yield-contributing traits in six field trials over two cropping seasons (Rabi 2020-21 and 2021-22) using a completely randomized block design (RBD) at two locations: the N.E. Borlaug Crop Research Centre (NEBCRC), G.B.P.U.A&T, Pantnagar, U.S. Nagar district, and the Agriculture Research Center Majhera, Nainital, Uttarakhand. The study aimed to assess genetic diversity among the genotypes via principal component analysis (PCA) and cluster analysis, offering insights into genetic variations. Three clusters were formed, with the maximum number of genotypes occurring in the second cluster. A lower p-value indicates that the clusters are statistically significant, suggesting that the observed diversity is not random. High estimates of cophenetic distance (.79) specify a high genetic distance between clusters, indicating that diverse genetic material is under study. The maximum genetic distance observed was 144.9 between genotypes G5 and G11. These findings suggest that these two genotypes are the most genetically diverse among all the studied genotypes and can be used as parents to develop high genetic variation in the studied traits. The PCA results yielded 18 principal components, with the first seven components accounting for approximately 83% of the total variance, indicating significant genetic diversity. The scree plot affirmed the robustness of the study’s results by suggesting that the first eight principal components accounted for a substantial portion of the variance.The findings of current study could be exploited in planning and execution of future breeding programme in wheat.

DNA taxonomy reveals high species diversity among the stygobiont genus Metastenasellus (Crustacea, Isopoda) in African groundwater

This study aimed to explore the species diversity within the isopod genus Metastenasellus in Benin and Cameroon. Compared to other parts of the world, the described diversity of stygobiotic crustaceans in Africa is low due to a dearth of studies and taxonomic expertise. However, recent research activities in Benin and Cameroon suggest higher groundwater diversity than previously envisioned. Recent sampling campaigns in these countries have shown that Metastenasellus is a major group in the underground aquatic environment. The accumulation of biological material provided an opportunity to explore species diversity within the genus using a DNA taxonomy approach based on the cytochrome c oxidase subunit I (COI) gene fragment. Despite the limitations of using a single-locus approach for species delimitation, an overview of the diversity within the genus Metastenasellus was obtained, revealing the presence of 23 distinct lineages. Several elements suggest that most, if not all, of these lineages represent valid species. These include high genetic distances between lineages, morphologically distinct species separated by genetic distances of the same order of magnitude as between other described lineages, and the coexistence of different lineages at the same stations. Despite a limited sampling effort, these first results indicate a high level of species diversity and endemism within Metastenasellus in the studied regions. The narrow geographic distribution of the lineages suggests strong isolation and limited dispersal abilities. This study highlights the potential for discovering a significant number of new species within this genus and emphasizes the need for further research to uncover the extent of diversity in African stygobiotic isopods.

RDNA and mtDNA analysis for the identification of genetic characters in the hybrid grouper derived from hybridization of Cromileptes altivelis (female) × Epinephelus lanceolatus (male)

BackgroundHybridization is a useful strategy to produce offspring with more desirable phenotypic characteristics than those of parents. The hybrid grouper derived from the cross of Cromileptes altivelis (♀, 2n = 48) with Epinephelus lanceolatus (♂, 2n = 48) exhibits improved growth compared with its female parent, which makes it valuable to aquaculture. However, the genetic traits of the hybrid grouper are poorly understood.ResultsThe observations showed that the hybrid grouper was diploid (2n = 48) and displayed intermediate morphology with the parent's measurable characteristics. The ribosomal DNA (rDNA) and mitochondria DNA (mtDNA) were characterized at molecular and phylogenetic level. High similarity and low genetic distance of 5S rDNA and mtDNA sequences between the hybrid grouper and C. altivelis showed that the hybrid grouper had a closer genetic relationship with female parents. The reconstructed phylogenetic tree based on COI gene and D-loop region of mtDNA recovered that mtDNA was maternally inherited in the hybrid grouper. Additionally, the DNA methylation level of 5S rDNA intergenic spacers (IGS) sequence was tested in here. The results showed that the DNA methylation status of the hybrid grouper was significantly lower than that of C. altivelis.ConclusionResults of this study provide important data on the genetic characteristics of the hybrid derived from the cross of C. altivelis and E. lanceolatus, and contribute the knowledge of both evolution and marine fish breeding.

Molecular Markers and Taxonomic Explosion in Herpetology: More or Less Robust Taxonomy? True and False Advantages of DNA Markers

Despite the increasing deficit of taxonomic expertise, the number of newly described species since the early 2010s has grown exponentially. This growth is related to the increased use of DNA markers in taxonomic descriptions. However, routine use of DNA markers in taxonomy did not bring practical taxonomy closer to the theory. Species are unique lineages with irreversible evolutionary pathways, and only the presence of distinct populations within the same geographic range, or at least the presence of narrow hybrid zones between the parapatric ranges is a conclusive evidence of evolutionary irreversibility. In the case of allopatric populations, only very high genetic distances, suggesting several tens of millions of years of independent evolution, can be used for validation of species status. This problem cannot be solved by the broader introduction of genomic phylogenies, which also fail to provide robust criteria for evolutionary irreversibility. We can hardly suppose that robust validation of species status is applicable to all or most of hundreds of thousands of animal species, including 20,000 amphibians and reptiles. Instead, practical taxonomy should concentrate on describing recognizable species, maintaining a trade-off between sufficiently detailed descriptions of world biodiversity and the applicability of these descriptions for practical use and metaanalyses, not pretending that formally described species reflect real lineages with independent and irreversible evolutionary pathways. Simultaneously, the non-critical elevation of the taxonomic status of individual geographic populations, contrary to the declared purpose of better-focusing conservation efforts, often has the opposite effect, leaving many formally described taxa outside the conservation umbrella.