Aeschynomene sp. prope villosa (a dalbergioid legume) represents a group of populations with morphological characteristics similar to those of Aeschynomene villosa, but without complete overlap, and whose cytogenetic characteristics subtly differ from both the latter and other related taxa. In this study, conventional surface spread and air-drying techniques, along with Giemsa staining, were used to analyze metaphase chromosome complements and karyotypes of individuals belonging to a population of A. sp. prope villosa, a taxon included in the Americanae series of Aeschynomene. The results confirm a previously obtained karyotypic formula. Differences observed in chromosome sizes do not modify the karyotype or its symmetry. They are interpreted here as a loss of gene flow between populations or adaptations to different ecogeographic conditions. The presence of chromosome stickiness in 7.4% of the nuclei analyzed is noteworthy. This aberration, not previously observed in Aeschynomene, primarily involves areas near the telomeres of apparently homologous and non-homologous chromosomes. This phenomenon, observed mainly in meiosis, has been linked to the tendency of chromosomes to clump together during cellular divisions following plant hybridization events. The same criterion of chromosomal interaction after hybridization could explain the changes in the number and position of satellites recorded in a previous study. Although unexpected, these results should not be surprising, since intergradation between A. villosa and A. americana, species with which it overlaps in its distribution area, has been suspected for at least 70 years. Furthermore, hybridization and allopolyploidy have already been demonstrated in other morphological series of Aeschynomene.
A crucial method for evaluating the potential harm to the genome caused by contaminants at levels exceeding the optimal threshold is the chromosomal plant assay. This paper reports on a study that examined the effects of varying concentrations of manganese (Mn) on the mitotic index (MI), cell kinetics index (CKI), and abnormality index (AI) in Glycine max L. root tip cells. Percentage of mitotic index, abnormality index, cell kinetics index, in root meristems of Glycine max L. at control and varying concentrations of Mn were evaluated. The findings showed that Mn doses that were utilized for seed treatment caused distinct differences in chromosomal activity of Glycine max L. root tip cells, with a decreased mitotic index and cell kinetics, and an increased abnormality index. Treatment was conducted at room temperature for 24 hours, 48 hours, and 72 hours at four different concentrations of Mn: CN (Control), 5μM, 10μM, 15μM, and 20μM. The control group was treated with distilled water. The findings demonstrated that Mn has cytotoxic and genotoxic effects on Glycine max L. root tip cells.
The fertilization of eggs may be delayed during induced fish breeding due to unforeseen circumstances. It is, therefore, necessary to know the optimal delay period and explore short-term storage options that can extend the viability of the eggs in such instances. In two studies, African catfish Clarias gariepinus eggs were obtained from broodstocks induced using ovaprim® hormone at 0.5ml/kg. A batch of the stripped eggs was then exposed in triplicate to atmospheric oxygen for 0, 1, 2, 3, 4, 8 and 12 hours post-stripping (HPS). In contrast, another batch was stored for 8 hours using sole and combined methods of “refrigeration”, “addition of extender” and “aeration”. The eggs were then fertilized using fresh sperm in all instances. In both experiments, egg characteristics, breeding parameters, and biometric parameters of hatched fry were recorded. Results showed a size reduction in the eggs as the time of exposure to atmospheric oxygen increased. Also, the fertilization and hatchability of eggs were similar to 4HPS; beyond this threshold, the value declined significantly to zero. However, the hatched fry’s biometric parameters showed no significant difference among treatments (P<0.05). The second study showed a poor breeding performance of eggs stored in all the different storage methods tested. Meanwhile, egg sizes and biometric parameters of the few hatched fry show no significant difference among the treatments (P<0.05). It was therefore concluded that the fertilization of stripped C. gariepinus eggs should not be later than 4HPS to optimize the breeding performance of the fish.
We investigated the intra-specific relationships between three Solanum species in Egypt: Solanum nigrum, Solanum villosum, and Solanum sinaicum, in addition to the inter-specific relationships among the populations of the three studied species. These species’ taxonomic difficulty is primarily due to its inconsistent infra-specific treatments in various floras. The morphological studies revealed distinguishing characteristics for the three investigated Solanum species mainly fruit and flower characteristics. The morphological differences allowed S. villosum to be divided into two subspecies: subsp. villosum, and subsp. miniatum. The genetic variation between the three Solanum species was clarified using AFLP technique. The ribosomal DNA ITS1-5.8S-ITS2 region of the three studied species was sequenced using the universal primers ITS4 and ITS5. The DNA sequences of Solanum species were counted. The karyotypes of the species under examination were established using the chromosome number and genome size acquired from mitotic chromosomal preparations.
The rapid rise of heavy metals and their extensive industrial use have raised concerns because these metals are released into the environment from both intentional and unintentional sources. When present in the environment in high concentrations, heavy metals may threaten the plant kingdom, particularly staple food crops. Nevertheless, little research has been done to identify the effects of heavy metals. The current study aims to assess the cytological alterations caused by lead (Pb) and copper (Cu) heavy metals on Glycine max Cv-JS-355. For two hours, Glycine max seeds were subjected to different Pb and Cu concentrations (CN, 25, 50, 75, 100, and 125 ppm). They were examined for their effects on chromosomal aberrations (CAs), micronucleus index (MNI), radicle length (RL), mitotic index (MI), cell death (CD), and seed germination (SG). The findings show a dose-dependent rise in MNI, CAs, CD and a substantial decrease in SG, RL, and MI. Furthermore, the percentage of abnormal mitotic cells, including cell nucleic leaking (CNL), Multi-pole division (MPD), Chromosomal bridge at telophase (CBT), chromosome retarded in anaphase (CRA), Dissociate chromosome in metaphase (DCM), increased in the Pb and Cu treated groups.
Cytogenetic studies provide valuable insights into the evolutionary dynamics of fish genomes, particularly in groups with high species diversity and ecological relevance. Among Neotropical cichlids, chromosomal data have revealed both conservation patterns and significant structural variations, reflecting intense karyotypic diversification. In this context, mapping repetitive DNA sequences has proven useful in aiding understanding of genomic organization and chromosomal evolution. However, information remains scarce for several cichlid genera. The present study investigated the chromosomal distribution of repetitive sequences, such as 18S and 5S ribosomal genes, as well as telomeric sequences, in three Amazonian species of Lugubria: L. cincta, L. strigata, and L. lugubris. The results revealed a diploid number of 2n = 48, along with variations in the karyotypic formula among the species. Mapping of repetitive sequences revealed distinct patterns of 18S rDNA distribution, with clusters located on different chromosome pairs. Conversely, the 5S rDNA showed a conserved position on a subtelocentric/acrocentric pair in all three species. Furthermore, the presence of interstitial telomeric sequences in L. cincta and L. strigata indicates greater genomic plasticity in these species, suggesting more pronounced chromosome dynamics in the genus Lugubria. These data contribute to the understanding of chromosomal evolution and diversification in this diverse group of Neotropical cichlids and may aid in future cytotaxonomic studies.
Corms and herbarium vouchers of 23 accessions belonging to five autumn-flowering Crocus species were gathered from nine Iranian provinces. For the materials under investigation, chromosome numbers, karyotype formulas and idiograms were documented. Chromosome number of 2n = 12 is reported for the first time in C. archibaldiorum and in the studied accessions of C. speciosus aggregate. Also, 2n = 24 were found in C. caspius, 2n = 8 and 10 in C. damascenus, and 2n = 14 and 16 in C. haussknechtii. In the latter two species, variation in chromosome number was correlated with karyotypic differences. Notably, C. archibaldiorum (2n = 12) had a longer total haploid of chromosome length than C. caspius (2n = 24). On a distribution map, possible correlations between karyological data and geography were indicated. To quantify variation in karyotypes, three inter- and intra-asymmetric karyotypic parameters were estimated. Also, statistical analyses were performed on five karyotypic characters to infer karyological relationships. The members of section Crocus (only C. haussknechtii) and section Nudiscapus occupied distinct positions. Furthermore, at the species level, all accessions of the same species tended to group together. The remarkable karyotypic variation among the studied accessions of C. damascenus and C. haussknechtii supported the previous assumption that these taxa still include undescribed species. It is underlined that changes in chromosome number and structure have played an important role in the evolution of the genus Crocus.
Cytogenetics laboratories often accumulate vast collections of cells fixed in Farmer’s solution (3 parts methanol to 1-part glacial acetic acid), stored long-term in freezers. While many of these samples are unsuitable for conventional cytogenetic analyses, they hold potential for molecular applications, especially as ethical restrictions around the collection of biological material through invasive procedures (e.g., biopsies, tissue excision, bone marrow aspiration) become increasingly stringent. However, extracting DNA from these cells presents significant challenges, such as structural fragility induced by the fixative and potential genetic material degradation, which can compromise subsequent analyses, including PCR. This study developed and standardized a protocol for extracting DNA from Farmer-fixed avian cells using accessible and low-cost reagents. The method proved economical and efficient, even for decades-old samples, recovering DNA suitable for cytogenomic and molecular studies. This approach significantly advances sustainable practices in science by utilizing long-stored samples that might otherwise be discarded, this approach provides a cost-effective strategy that reduces the need for new collections and aligns with current ethical guidelines in molecular genetics research. Compared to commercial kits, the protocol demonstrated economic viability while expanding the use of biological collections in genetic research and evolutionary studies.
In this study, Triticum growth inhibition test was used to determine the effects of this fungicide on root and stem growth and % mitotic index. For this purpose, Kate A1 Russian wheat variety was used as test material. According to the Triticum root growth test, the concentration value that halves the root length is known as the 50 EC50 (effective concentration) value. According to the test, root length of the control group was 9.38 ± 0.66 cm and stem length was 9.56 ± 0.88 cm. According to Triticum test, the EC50 value of the fungicide was found to be approximately 5000 ppm. Some doses of this fungicide used (2500, 5000 and 10000 ppm) were observed to inhibit root and stem growth and all the results were statistically significant according to Dunnet-t test. % In the root mitotic index analysis studies, 5000 cells were counted for the doses and it was observed that the tested concentrations of 1250, 2500, 5000 and 10000 ppm decreased mitotic activity. It was observed that the concentration of 10000 ppm decreases the mitotic index (11.02 ± 2.35 cm) the most. The highest recommended dose of the tested fungicide in the fight against agricultural pests is 1000 ppm and the EC50 value is determined as 5000 ppm according to the test results indicating that the cytotoxic effects of this fungicide will be limited. In MTT assay, toxic effects were observed at all concentrations and time applications of 70% Thiophanate Methyl fungicide. Dose and time dependent decreases in cell viability were observed. These results show that the fungicide has a cytotoxic effect on MDBK cells at the doses used.
Caper (Capparis spinosa) is a shrubby, deciduous perennial medicinal plant belonging to the Capparaceae family. Its use is in folk medicine, pharmacy, food, and spices. Chromosome, ploidy analysis, and flow cytometric genome size of 10 populations collected from different parts of Iran were analyzed. The results showed that all populations were diploid, with nine populations having 2n = 2x = 30 (P1-P8, P10) and one population having 2n = 2x = 34 (P9) chromosomes. The average chromosome length (CL) for these two chromosome groups was 1.05 and 0.97 μm, respectively. The mean monoploid genome sizes for the populations with 30 and 34 chromosomes were 0.646 and 0.633 pg, respectively. As a whole, the mean genome size of all populations was 0.643 pg. The chromosome number as well as the genome size are being reported for the first time. Cluster analysis and principal component analysis revealed a categorization of the caper population into four distinct groups. The first group comprised three populations (P1, P3, and P4), while the second group included only P2 population, the third group was represented by two populations (P5 and P7), and the fourth group encompassed four populations (P6, P8, P9, and P10). Future research on the genetic traits and breeding methodologies of this species can build upon the foundational findings of this study.
The Menyanthaceae, an aquatic plant family, is distinguished by extensive polyploidy and heterostyly. This study marks the first cytogenetic characterization of four Menyanthaceae species from Korea – Menyanthes trifoliata, Nymphoides peltata, N. indica, and N. coreana – employing fluorescence in situ hybridization (FISH) with 45S and 5S rDNA probes. All four species exhibit exclusively metacentric chromosomes, with M. trifoliata and N. peltata being hexaploid (2n = 54), N. coreana tetraploid (2n = 36), and N. indica diploid (2n = 18). FISH mapping revealed between one to four 45S rDNA loci and one to three 5S rDNA loci per species, showing that rDNA site number does not correlate directly with ploidy level. The karyotypic data suggest a conserved base chromosome number (x = 9) and largely symmetrical karyotypes across these species. Notably, M. trifoliata presents fewer rDNA loci than expected for a hexaploid, indicating genomic rearrangements and rDNA locus loss through diploidization. These observations highlight an evolutionarily stable genome structure in M. trifoliata, despite its polyploid nature. This study elucidates the chromosomal organization and evolutionary dynamics of the Menyanthaceae, emphasizing the role of polyploidy and rDNA evolution in genome structuring. The findings enhance our understanding of plant cytogenetics in aquatic ecosystems and serve as a foundation for further comparative genomic and evolutionary studies in Menyanthaceae.
The clones of BAC library combined with FISH are an excellent tool for mapping and identifying full-length genes. The present study was to sequence, mine and characterize the BAC clones of Clarias magur (magur) genome. The end sequences of the BAC clones were bioinformatically mapped onto the genome scaffolds of magur to identify and locate the genes in each clone and FISH was utilized to locate clones on specific chromosomes of magur. A total of 13 BAC clones could be mapped using BAC end sequences on 12 genome scaffolds of magur. From the 13 clones, 34 genes were mined, annotated and characterized. Physical mapping using BAC-FISH signal was used to localize two clones, 012H23 and 012H7 on 11th and 14th chromosome pairs of magur. The gene enrichment analysis revealed involvement of several genes in growth and regulatory processes, such as protein neddylation and metal ion transport. PPI Network analysis revealed two types of interactions among 11 nodes and between 10 edges; and 4 genes (ash2l, cnot2, lin7c, uba3) were identified to be important. The study reveals the presence of important genes on the 13 undertaken clones, making this a useful genomic resource. The FISH probe could not only be helpful in generation of basic information of gene location for identification of genes on the chromosomes as a chromosome marker, but also in detection of chromosomal defects arisen due to genetic mutation occurred if any on a particular location of reported genes in C. magur.
In this study, anther wall structure and the embryological features of male gametophyte development in Jurinea kilaea from Asteraceae family are described for the first time. Capitula of different sizes containing young flower buds of J. kilaea was collected from Tekirdağ, Saray - Kastro coast in July 2022 – 2024. Anthers separated according to their sizes under a stereo microscope were passed through arising alcohol series and embedded in Hisstore. Toluidine blue O solution was used to stain the sections. Slides were examined with light microscope and photographed by an Olympus E330 camera. In J. kilaea, anthers are tetrasporangiate. Anther wall consists of the outermost epidermis, the endothecium, the middle layer and the innermost tapetum layer. Tapetum cells appear to have 1 or 2 nuclei. Tapetum is plasmodial type and, tapetum cells begin to degenerate towards the end of the tetrad phase. Microsporogenesis and pollen mitosis are generally regular. Asynchrony is observed during meiosis in young anther loci. Generally, decussate type tetrad was observed. Rarely pentads were also observed. Cytoplasmic channels were observed between microspores at different stages of microsporogenesis. The mature pollen grains of J. kilaea are generally composed of three nuclei and have a normal structure. However, there have been instances where pollen grains exhibit an abnormal structure. Pollen sterility ratio was found to be 12.1%.
The Lomariopsidoid deer tongue fern genus Elaphoglossum, with about 600 epilithic species, is with either monomorphic or partially dimorphic simple fronds having acrostichoid sori. Due to the rare occurrence of fertile fronds, chromosome number reports are rarely available with the presence of maximum number of diploid species with n=41. Out of seven species of Elaphoglossum from India, five species are present on the Western Ghats of South India itself with three South Indian endemic species. The present study shows that the globally threatened endemic fern Elaphoglossum nilgiricum Krajina ex Sledge from the type locality Nilgiris, India is a tetraploid sexual with 2n=164 chromosomes. This is the first chromosome count for this globally threatened South Indian endemic fern E. nilgiricum Krajina ex Sledge.
Premature ovarian failure (POF) is a clinical syndrome that is characterized by loss of ovarian function in women of childbearing age and generally occurs before the age of 40. Genetic causes account for about 20 to 25% of cases of POF. However, in many cases, the origin of the condition remains idiopathic. The objective of this study was to perform cytogenetic research in a group of patients affected by POF in order to identify the type and frequency of chromosomal alterations. Fifteen patients were referred to the Human Cytogenetics Laboratory of the Amazonas State University (UEA) by gynecology specialists from two public health institutions in Manaus, Amazonas, Brazil, for chromosomal analysis. The analysis was performed via peripheral blood lymphocyte culture using the GTG banding method. The karyotypes were assembled with the help of the GeneAll-HD® software and the results were interpreted according to the ISCN 2016 standards. Of the fifteen patients analyzed, nine (60%) had no chromosomal abnormalities, while six (40%) exhibited chromosomal abnormalities. Of the alterations identified, three patients (20%) presented numerical alterations of the X chromosome with mosaicism, two patients (13%) showed autosomal numerical alterations involving chromosomes 15 and 21, both with mosaicism, and one patient (7%) exhibited a structural alteration in the form of terminal deletion of the long arm of the X chromosome. The results obtained in this study have the potential to improve the accuracy of the diagnosis, assist in medical decisions, provide adequate prognoses and facilitate reproductive management through genetic counseling.
Assessing genome size in plant species using flow cytometry requires fresh plant material from both the target species and appropriate internal standards. The use of fresh material from the standards is sometimes difficult. For this reason, a research about three preservation methods and their results when using the plants in flow cytometry has been conducted. We have focused on four of the most used internal standards in flow cytometry to estimate the nuclear DNA amount. Our results pointed out that the best method of conservation was lyophilisation. The conservation method based on drying with silica gel is more advisable to establish the ploidy level than to provide an absolute value of nuclear DNA content. Finally, ultrafreezing is not an appropriate preservation method.
Chromosome studies were conducted on bat species in the Nsukka Local Government Area of Enugu State, Nigeria, to determine their karyotypes and assess relatedness. Chromosomes were isolated from the bone marrow and testes of various bat species using 0.4% colchicine for cell division arrest. A calibrated eye-piece graticule was used for counting and measuring chromosomes from prepared slides. Calculations for arm ratios and centromeric indices were performed to categorize chromosomes, and ideograms were created based on these measurements. Standard karyotypes for each species were established using photomicrographs of mitotic metaphase chromosomes. A total of eight bat species were sampled, representing the suborders Yinpterochiropera and Yangochiroptera. The species included Epomophorus wahlbergi, Epomophorus gambianus, Microteropus pusillus from Yinpterochiropera, and Nycteris major, Nycteris grandis, Nycteris arge, Scotophilus diaganii, and Scotophilus leucogaster from Yangochiroptera. The diploid chromosome numbers (2n) and fundamental numbers (FN) were as follows: Epomophorus wahlbergi (2n=35, FN=70), Epomophorus gambianus (2n=36, FN=79), Microteropus pusillus (2n=36, FN=79), Nycteris major (2n=40, FN=80), Nycteris grandis (2n=42, FN=82), Nycteris arge (2n=40, FN=78), Scotophilus diaganii (2n=36, FN=45), and Scotophilus leucogaster (2n=36, FN=54). Variations in 2n and FN were attributed to centric fission and loss of p arm segments in some chromosomal pairs, leading to different morphological traits observed in the bat species. The study highlights the rich diversity of bat species in Nsukka and supports the use of karyotyping as an effective method for species differentiation.
Cytological study in four species of Colocasia (Araceae) of Assam showed a variation of chromosome numbers. Basic chromosome number of the species was reported as n= 14. Dominance of metacentric chromosomes in all the four species and symmetric karyotypes indicate the primitive evolutionary status of the species. Analysis of chromosome asymmetry indices indicate the karyotype homogeneity. Deviation of basic chromosome numbers in Colocasia manii Hook. f. and Colocasia fallax Schott. reflects the possible existence of aneuploidy. Presence of secondary constriction indicates the chromosomal plasticity.
Bimodal karyotypes, initially defined by Avdulov, are characterized by one large and one small set of chromosomes, reflecting a particular type of karyotype asymmetry. Despite later discussions by Stebbins, the absence of a quantitative criterion has led to subjective classifications. This study revisits the concept of bimodality through a literature review and proposes an objective criterion based on the ratio between the smallest chromosome of the larger set and the largest of the smaller set. Chromosome morphology and asymmetry were analyzed in 32 species previously classified as bimodal. Statistical tests were applied to detect size discontinuities and assess bimodality. We propose two forms of bimodality, interchromosomal and intrachromosomal, considering differences in size and morphology. Our results show that Drosophila melanogaster and Scaphura nigra exhibit trimodal karyotypes. A ratio of ≥1.5:1 between chromosomal subsets provides a clear and objective criterion for defining bimodality, aligning with the original concepts of Avdulov and Stebbins.
Gamma irradiation is a powerful tool in mutation breeding, promising to boost plant productivity and yield while influencing phytochemical composition and morphological traits. This study focuses on understanding the effects of gamma irradiation on Chia (Salvia hispanica L.) seed development, encompassing germination, growth, and photochemical properties. Ionizing radiation has proven to be a potent physical agent in mutation breeding initiatives, potentially enhancing plant productivity and yield. A comprehensive analysis was conducted, encompassing the application of distinct gamma irradiation doses ranging from (0, 50,100, 150, 200, and 250 Gy) in M1(2021-22) and M2 (2022-23) and oils were extracted in M2 generation using the Soxhlet technique. Various parameters, including sterol composition, fatty acid composition, tocopherol content, and fatty acid value (FAV), were meticulously analyzed using the Gas Chromatography-Mass Spectrometry (GC-MS) technique. Increased phytochemical viz., Alpha-linolenic acid (60.23%), Linoleic acid methyl ester (19.78%), and Palmitic acid (11.96%) were obtained at 100 Gy irradiation that had not been reported in earlier research. Therefore, the potential of gamma irradiation to enhance chia seeds’ nutritional and phytochemical properties exists. This insight holds promise for advancing seed development and overall plant performance, offering valuable prospects for crop improvement and the creation of nutrient-rich agricultural products.
