Showing papers in "Cytologia in 2007"
TL;DR: Isolation of seven different types of trisomics was possible in the advanced generations of an induced trisomic recovered earlier in grass pea cultivar BioR-231, and leaflet character could be used conveniently as a marker character for identification and classification of seven types.
Abstract: Summary Isolation of seven different types of trisomics was possible in the advanced generations of an induced trisomic recovered earlier in grass pea cultivar BioR-231. The trisomic plants were phenotypically distinguishable from the diploid mother cultivar (2n� 14) by their contrasting morphological characteristics and cytologically by the presence of an extra chromosome (2n� 1� 15). Variations in several morphological traits were distinctive and stable in different trisomic plants during succeeding generations. Among the phenotypic manifestations, modifications in leaflet morphology, stipule character and seed coat colour were specific for each of the seven types of trisomics. The different trisomics could be distinguished instantly from one another by the characteristic shape, number, position and orientation of leaflets as well as stipules. Since leaflet character was specific and distinctly visible at the very seedling stage it could be used conveniently as a marker character for identification and classification of seven trisomics. Moreover, apical modification of leaflet, complete absence or occurrence of stipule in different forms and variations in floral morphology were also conspicuously different in different types. The extra chromosome appeared as univalent or in trivalent association and the trivalents occurring only in linear or frying pan or Y shaped configuration characterized all of the 7 types as primary types. Pollen sterility and reduced seed yield in these trisomic types might be the consequences of unequal separation, formation of laggard and anaphase bridge.
42 citations
TL;DR: The overall karyotypic features suggested S. villosum as an ancient auto-tetraploid of S. americanum which in course of time has started regular meiosis.
Abstract: Two species of the genus Solanum viz. S. nigrum and S. villosum found in Bangladesh were cytogenetically investigated to confirm their taxonomic status. S. nigrum and S. villosum were found to possess 2n=24 and 2n=48 chromosomes, respectively. The centromeric formula 22m+2sm was found in S. nigrum and 48m in S. villosum. No gradual decrease of chromosomal length was observed in both the species indicated their karyotypes as primitive type. The individual chromosomal length ranged from 1.66 to 2.34 μm in S. nigrum and 1.66 to 2.66 μm in S. villosum. The total chromatin length in S. villosum (97.8 μm) was almost double to that of S. nigrum (48.94 μm). The range of relative length of chromosomes was similar in these two species. Solanum nigrum and S. villosum possessed 18 and 17 CMA positive bands, respectively. Most of the CMA-bands were present at the terminal region in both the species. The percentage of CMA banded region in S. villosum (35.43) was almost double to that of S. nigrum (18.69). A pair of DAPI positive bands was found on both the end of all the chromosomes in these 2 species. Each band was 0.5 μm in length. The karyotype of S. nigrum studied here indicated that the specimen was not actually S. nigrum rather it has much simillarities with S. americanum. Solanum villosum showed regular bivalent formation at metaphase-I and segregation at anaphase-I. The overall karyotypic features suggested S. villosum as an ancient auto-tetraploid of S. americanum which in course of time has started regular meiosis.
33 citations
TL;DR: Three distinct variants differing for their phenotypic appearance and floral characters were identified and isolated in M1 generation of 200 Gy gamma irradiated set in Lathyrus sativus and subjected to meiotic analysis to understand their genotypic sensitivity to induced cytological changes.
Abstract: Three distinct variants differing for their phenotypic appearance and floral characters were identified and isolated in M1 generation of 200 Gy gamma irradiated set in Lathyrus sativus. They were subjected to meiotic analysis to understand their genotypic sensitivity to induced cytological changes. One interesting abnormality encountered during the present study was nucleolar dysfunctioning in the treated plants. Despite of chromosomal abnormalities like laggards, stickiness, micronuclei, etc. chiasma frequency was found to increase in the 3 plants isolated at 200 Gy dose of gamma rays. Pollen fertility was also moderately affected.
21 citations
TL;DR: Karyotype analysis of Withania somnifera revealed 7 morphologically distinct chromosome types and secondary polyploidy has been attributed as the possible cause of secondary association of chromosomes and the basic chromosome number has been suggested to be x=12.
Abstract: Karyotype analysis (through Image Analyzing System) of Withania somnifera revealed 7 (2n=48: 4Asmsc+4Bm+14Cm+4Dsm+2Est+18Fm+2Gsm) morphologically distinct chromosome types. The karyotypes showed prevalence of chromosomes with median primary constrictions. Satellites were associated with short arm of 4A-type chromosomes. Chromosome length in the complement varies from 1.43 to 2.64 μm. The karyotype was symmetric in nature (TF%: 42.26). Root tip squash preparations revealed polysomatomy (2n=12: 5.8%, 2n=18: 4.8%, 2n=24: 2.9%, 2n=36: 25.0%, 2n=48: 57.7% and 2n=72: 3.8%) with predominance of 2n=48 chromosomes. The meiocytes had 2n=48 chromosomes always with an average of 23.52 II+0.95 I per cell. The bivalents formed rods (rods: 20.64±0.15, rings: 2.90±0.17) mostly at diplotene with mean chiasma of 26.45±0.25 per cell. A persistent feature in 76.2% metaphase I cells was the presence of secondary association of chromosomes and the chromosomes tended to form groups of 3 (8.0%), 6 (32.0%), 9 (16.0%) and 12 (44.0%). Secondary polyploidy has been attributed as the possible cause of secondary association of chromosomes and the basic chromosome number of the species has been suggested to be x=12.
20 citations
TL;DR: The seeds of Nigella sativa were treated with 50, 100, 150, 200, 250, 300 Gy doses of gamma rays and a hexapetalous mutant was observed at 100 Gy dose in M1 generation, which can be suggested to be beneficial for mutagenesis in plants.
Abstract: The seeds of Nigella sativa were treated with 50, 100, 150, 200, 250, 300 Gy doses of gamma rays. A hexapetalous mutant was observed at 100 Gy dose in M1 generation. It was found to have increased seed weight and seed number as compared to the control plants. The chromosomal abnormalities at 100 Gy dose were also at the optimum level (17.10%). Therefore, this dose can be suggested to be beneficial for mutagenesis in plants.
19 citations
TL;DR: Three sympatric species of Gymnotus from the Fundo stream, a small tributary of the Sapucai river, Minas Gerais State, Brazil, were studied in relation to their karyology and cytogenetic data obtained indicate that Gym notus sp.
Abstract: Three sympatric species of Gymnotus from the Fundo stream, a small tributary of the Sapucai river, Minas Gerais State, Brazil, were studied in relation to their karyology. Gymnotus sylvius presented 2n=40 chromosomes (36 m/sm+4 st/a), Gymnotus sp. presented 2n=50 (26 m/sm+24 st/a) and Gymnotus paraguensis had 2n=54 (50 m/sm+4 st/a). C-banding demonstrated positively stained heterochromatic blocks in the centromeric position of few chromosomes on G. sylvius and in the centromeric region of all chromosomes on G. paraguensis samples. The nucleolus organizer region (NOR) was located on the short arm of one st chromosome pair in G. sylvius and Gymnotus sp., and in the interstitial position on the short arm of the pair number one and below the centromere on a third chromosome on G. paraguensis. The cytogenetic data obtained indicate that Gymnotus sp. represent a new Gymnotus specie with a karyotypic constitution never observed on others species from this genus. Some aspects related to the chromosome diversification of these Gymnotus are discussed.
18 citations
TL;DR: A combination of morphological, cytogenetic and RAPD molecular markers may be of grate use in planning the cotton hybridization and breeding programs.
Abstract: Cytogenetic and RAPD markers variations were studied in 10 tetraploid cotton cultivars. ANOVA test revealed significant differences in cytogenetic characteristics including chiasma frequency and distribution as well as chromosome pairing among the studied genotypes, indicating their genomic differences. Quadrivalents were formed in all the cultivars except 1, while post pachytene diffuse stage, chromosome stickiness and laggards occurred almost in all the cultivars studied. Twenty-seven RAPD primers out of 30 could produce bands. In total 362 bands were obtained in which 69 were polymorphic (19.00%) and 293 bands were monomorph (81.00%). The cultivar No. 200 possessed the highest number of bands while No. 228 and Gukurova possessed the lowest number. Among the RAPD bands produced, 8 were specific in the cultivar No. 200 and 3 in the cultivar V. Sahel X 4-S-4, indicating the use of RAPD markers in cotton cultivars discrimination. Grouping of the cultivars based on cytogenetic and molecular markers were partly in agreement. A combination of morphological, cytogenetic and RAPD molecular markers may be of grate use in planning the cotton hybridization and breeding programs.
18 citations
TL;DR: Karyotype analysis of 3 released varieties in Vigna radiata L. r adiata has been carried out after staining with orcein, CMA and DAPI, and it was possible to develop marker chromosomes for authentic identification of three varieties.
Abstract: Summary Karyotype analysis of 3 released varieties in Vigna radiata L. viz. Barimung-2, Barimung-3, Barimung-5 has been carried out after staining with orcein, CMA and DAPI. These varieties were found to possess 2n� 22 chromosomes. Four terminal CMA-positive bands were found in Barimung-2, 3 such bands in Barimung-3 and 4 in Barimung-5. The terminal CMA positive bands showed deep DAPI-negative reversible bands in the 3 varieties of V. r adiata. One chromosome of Barimung-5 was fluoresced entirely with CMA and DAPI. DAPI-positive and DAPI-negative band occurred in another chromosome of Barimung-5. A pair of interstitial CMA-negative band was observed in chromosome pair V of only Barimung-2. These portions were stained brightly with DAPI. These kinds of reversible banded chromosomes could be easily identified. Polymorphism regarding the number and location of DAPI-positive bands were observed in these varieties. That may due to either minute deletion or high condensation of heterochromatic region at the respective loci. Few chromosomes of each variety showed characteristic CMA and DAPI bands. Therefore, with the help of CMA and DAPI it was possible to develop marker chromosomes for authentic identification of three varieties in V. radiata.
17 citations
TL;DR: Evidence is obtained of a wide chromosomal variation, either in number and structure that could be integrated with morphological and molecular data in phylogenetic studies.
Abstract: Among the Perciformes, Cichlidae represent the more specious group, geographically distributed in Africa, Asia and America. In the present work, 7 species of 5 genera of cichlids from the Parana River (Misiones, Argentina) were cytogenetically characterized and discussed some aspects of the chromosome evolution. The following chromosome numbers and formulaes: were found for each analyzed species: Crenicichla niederleinii 2n=48 (6 M-SM; 42 ST-A), Crenicichla lepidota 2n=48 (6 M-SM; 42 ST-A), Gymnogeophagus sp. n. 2n=48 (2 M-SM; 46 ST-A), Gymnogeophagus balzanii 2n=48 (2 M-SM; 46 ST-A), Apistogramma trifasciata 2n=46 (16 M-SM; 30 ST-A), Cichlasoma dimerus 2n=48 (8 M-SM; 40 ST-A) and Bujurquina vittata 2n=44 (22 M-SM; 8 ST-A; 14 microchromosomes). The C-positive heterochromatin was observed preferentially in pericentromeric regions of some chromosomes and NORs at the secondary constriction on the first chromosome pair. In B. vittata the microchromosomes are not heterochromatic and the 5th pair shows short arms entirely stained and, in coincidence, the AgNORs appears located at the same region. The results obtained evidence a wide chromosomal variation, either in number and structure that could be integrated with morphological and molecular data in phylogenetic studies.
17 citations
TL;DR: UNESP Universidade Estadual Paulista Julio de Mesquita Filho Laboratorio de Citogenetica de Insetos, S.Jose do Rio Preto.
Abstract: UNESP Universidade Estadual Paulista Julio de Mesquita Filho Laboratorio de Citogenetica de Insetos, S. Jose do Rio Preto, SP
15 citations
TL;DR: It is suggested that oxygen triggers light independent proplastid development with the oxidative metabolism of lipids providing the carbon and energy for the synthesis of nucleic acids and proteins required for proplASTid development in the dark.
Abstract: Euglena grown to stationary phase in the dark without aeration accumulated lipids. When these high lipid cells are transferred to an inorganic medium and aerated, lipids were rapidly metabolized and the respiratory rate declined concomitant with the decline in cellular lipid content. Prolamellar bodies, propyrenoids and prothylakoids developed within the proplastid of dark aerated cells and the cells developed an increased capacity for chlorophyll synthesis manifested upon subsequent exposure to light. Lipid content did not decline in cells exposed to nitrogen and chlorophyll synthesis ability did not increase. The addition of an organic carbon source to cells at the start of aeration did not prevent lipid degradation. Organic carbon source addition and inhibitors of RNA and protein synthesis did however inhibit the development of an increased capacity for chlorophyll synthesis. These results suggest that oxygen triggers light independent proplastid development with the oxidative metabolism of lipids providing the carbon and energy for the synthesis of nucleic acids and proteins required for proplastid development in the dark.
TL;DR: Karyotypic study of 3 species of Neolissocheilus hexagonolepis, Puntius ticto and P. chola belonging to family Cyprinidae, from Arunanchal Pradesh, India, were carried out and the evolutionary significance of these 3 karyotypes was discussed.
Abstract: Karyotypic study of 3 species of Neolissocheilus hexagonolepis, Puntius ticto and P. chola belonging to family Cyprinidae, from Arunanchal Pradesh, India, were carried out. The diploid chromosome number in Neolissocheilus hexagonolepis was 100 with a chromosomal formula of 32m+16sm+6st+46T and fundamental arm number (FN) as 148. The other 2 species, Puntius ticto and P. chola have 50 chromosome with chromosomal formula of 28m+16sm+6st (FN=94) and 2m+2sm+46T (FN=54), respectively. The evolutionary significance of these 3 karyotypes was discussed.
TL;DR: The overall karyotypic features indicated that the Tall form is quite different from the other 2 and thus it may be placed in different taxonomic rank, however, the Slender form may be considered as a trisomic variety of T. trilobatum (Typical form).
Abstract: Typhonium trilobatum (Typical form) and its 2 morphological forms viz. Tall and Slender were cytogenetically investigated. The Typical and the Tall form were found to possess 2n=18 chromosomes whereas the Slender one has 2n=19 chromosomes. The extra chromosome of the Slender form was a regular member of pair IX. The centromeric formula of the Tall form was 12m+6sm. It was 16m+2sm and 17m+2sm in the Typical and the Slender form, respectively. The orcein-stained interphase nuclei and prophase chromosomes revealed that the Tall form had much less heterochromatins than the other 2 forms. The Tall form possessed a pair of satellites which were found in orcein and CMA-staining. In DAPI staining, satellites showed negative banding which indicated its GC-rich nature. Satellite was not found in other 2 forms. Few chromosomes in the Typical and the Tall form fluoresced entirely with CMA. It indicated that these forms might have derived those chromosomes from a common ancestor. Due to the unique nature, those chromosomes could be used as marker. DAPI banded karyotypes showed similarities between the Typical form and the Slender form. It was much different in the Tall form. The overall karyotypic features indicated that the Tall form is quite different from the other 2 and thus it may be placed in different taxonomic rank. However, the Slender form may be considered as a trisomic variety of T. trilobatum (Typical form).
TL;DR: Successful hybridization between pearl millet and this new cytotype shall be important for introgression of useful traits as well as to study inheritance of traits such as perenniality, apomixis and tolerance to stresses.
Abstract: Pennisetum squamulatum is an important species belonging to tertiary gene pool of cultivated pearl millet as potential donor of several genes. Recently a new cytotype with 2n=56 chromosmes has been identified. Crossability of this cytotype has been studied with diploid and induced tetraploid pearl millet. The hybrids produced with this novel cytotype were compared for their characteristics with the hybrids previously reported with widely reported 2n=54 P. squamulatum cytotypes. Strong incompatability barriers were observed between 2n=56 cytotype with diploid pearl millet, and hybrids could not be obtained even after embryo rescue. Limited crossability was obtained with tetraploid pearl millet and 2 successful hybrids were produced. Their hybridity was confirmed by morphology, flowcytometry and cytology. The hybrids were highly fertile, perennial and segregated for mode of reproduction. Segregation for other traits confirmed heterozygous nature of P. squamulatum 2n=56 cytotype. Cytological investigations suggested 2n=8x nature of this cytotype. Successful hybridization between pearl millet and this new cytotype shall be important for introgression of useful traits as well as to study inheritance of traits such as perenniality, apomixis and tolerance to stresses.
TL;DR: Dominant markers such as Random Amplified Polymorphic DNA (RAPD) for the evaluation of relatedness among 6 Piper species were included in this study to ensure such technique for claiming intellectual property right (IPR) by the plant breeder.
Abstract: The present study utilized dominant markers such as Random Amplified Polymorphic DNA (RAPD) for the evaluation of relatedness among 6 Piper species were included in this study and to ensure such technique for claiming intellectual property right (IPR) by the plant breeder. Further, the study also aimed at estimation of the genetic relatedness of these 6 morpho-agronomically contrasting species. Six Piper species were screened using RAPD with decamer primer of arbitrary sequence. Out of 100 primers screened 12 were selected which gave clear and bright fragments. DNA banding patterns generated by RAPD were recorded as ‘1’ for presence of the RAPD marker and ‘0’ for absence. Genetic distance between these 6 species was calculated based on the RAPD data set as per Squared Euclidean distances. Based on the number of bands all the species were grouped into 3 clusters and the dendrogram revealed maximum similarity between P. betel and P. longum and also in between P. nigrum and P. mullesua species, altogether forming one cluster. The standardized method can identify any of the single hybrid or species tested.
TL;DR: Fluoride salts present in the ground water might have interfered the phagocytosis and produce oxygen free reactive radicals that attack the nucleophilic sites of the DNA leading to the loss of important gene segments responsible for cell growth and the ageing.
Abstract: Summary Non-permissible concentration of fluoride salts in ground water induces various anomalies in human beings. Bhagalpur city’s ground water contains 1‐2 ppm of fluoride. Its genotoxic effects were assessed in Swiss albino mice Mus Musculus. 25% (50 mg/l) and 50% (100 mg/l) concentrations were found to increase the frequency of abnormal cells by 10.33 and 19.33% and chromosome abnormalities by 10.33 and 20.00% in bone marrow cells. The increase in frequency of chromosome anomaly was mainly due to significant increase in individual type, viz. chromatid breaks, gaps and acentric fragments. The effect is dose dependent. Fluoride salts present in the ground water might have interfered the phagocytosis and produce oxygen free reactive radicals that attack the nucleophilic sites of the DNA leading to the loss of important gene segments responsible for cell growth and the ageing.
TL;DR: Differential staining with orcein, CMA and DAPI were used to characterize the karyotypes of three cultivated varieties of Lens culinaris Medik and revealed that deletion near the banded region of metacentric chromosomes of Barimasur-2 might result the formation of terminal CMA-banded sub-metacentric chromosome in BarimAsur-3.
Abstract: Differential staining with orcein, CMA and DAPI were used to characterize the karyotypes of three cultivated varieties of Lens culinaris Medik viz. Barimasur-2, Barimasur-3, Barimasur-4. In Barimasur-2 and Barimasur-3, 2n=14 chromosomes were found. Whereas in Barimasur-4, 2n=15 chromosomes were observed indicates the variety as trisomic. Two CMA-positive bands were found at the pericentric region of 2 metacentric chromosomes in Barimasur-2. Barimasur-3 had 2 terminal CMA-positive bands in 2 different sub-metacentric chromosomes. The size of CMA-bands, total CMA-banded area, percentage of CMA-positive banded region of Barimasur-2 and Barimasur-3 were almost similar. The total chromatin length of Barimasur-3 (97.83 μm) was found to be less than that of Barimasur-2 (107.05 μm). These data revealed that deletion near the banded region of metacentric chromosomes of Barimasur-2 might result the formation of terminal CMA-banded sub-metacentric chromosomes in Barimasur-3. No CMA-positive band was found in Barimasur-4. Six DAPI-positive bands were found in Barimasur-2. Barimasur-3 and Barimasur-4 had 11 and 13 DAPI-positive bands, respectively. Heteromorphicity in respect of DAPI bands between the homologue members was found in several chromosome pairs in these three varieties. With the help of DAPI banding it was possible to identify the pair-II of Barimasur-2 and pair-I in Barimasur-4. Therefore, different CMA and DAPI banding patterns were observed in 3 varieties.
TL;DR: Detailed karyotypes and the fluorescence in situ hybridization using 5S and 18S rDNA probes was applied to 3 species of the genus Juniperus, and the first time chromosome makers of the family Cupressaceae are reported.
Abstract: Detailed karyotypes and the fluorescence in situ hybridization (FISH) using 5S and 18S rDNA probes was applied to 3 species of the genus Juniperus. The number of chromosomes of J. chinensis var. sargentii and J. lutchuensis was 2n=22, except for J. chinensis var. procumbens (2n=44). Chromosomal sites of 5S rDNA were on one pair of the short arm of the median-centromeric chromosome and 18S rDNA were at the secondary constriction. No minor signals of 5S and 18S rDNA probes were detected in the Juniperus chromosomes. We developed karyotypes using McFISH with 5S and 18S rDNA, and reported the first time chromosome makers of the family Cupressaceae.
TL;DR: The wide polymorphisms and the differences in location and quantity of heterochromatins in 2 A. scabripinnis populations, which are isolated from each other by waterfalls along the Canta Galo stream (Sao Paulo State, Brazil), are described.
Abstract: Summary Studies on different populations of the Characidae fish Astyanax scabripinnis, a species complex, have shown the occurrence of many levels of cytogenetic polymorphisms, such as in the positioning and amount of constitutive heterochromatins, and in the localization of nucleolar rDNA sites. The present paper describes the wide polymorphisms and the differences in location and quantity of heterochromatins in 2 A. scabripinnis populations, which are isolated from each other by waterfalls along the Canta Galo stream (Sao Paulo State, Brazil). Samples from both populations presented the same karyotype formulae. The specimens from the population located at 980 m of altitude revealed few variations in heterochromatins and NORs sites. On the other hand, those specimens collected from 720 m showed high variability in positioning and number of C-bands and rDNA loci. Events of transposition between telomeric segments, preferential positioning of the nucleolar rDNA clusters and the presence of GC-rich heterochromatins are also discussed.
TL;DR: The authors' asymmetry index based on A 1 value has indicated that the chromosomes in some Japanese Artemisia evolved in order of section Dracunculus, Absinthium and Artemisia.
Abstract: Summary To clarify the chromosomal evolution among the 3 sections (Absinthium, Artemisia, Dracunculus) of Japanese Artemisia, we use numerical cytogenetic analysis based on karyotypes. The intra- (A1) and interchromosomal (A2) asymmetry index, which does not depend on chromosome number or chromosome size. Our asymmetry index based on A 1 value has indicated that the chromosomes in some Japanese Artemisia evolved in order of section Dracunculus, Absinthium and Artemisia. The A 1 index indicated that x� 9 was the ancestral basic chromosome number of this genus while x� 8 was advanced, and based on x� 17 was plotted between speies with x� 9 and x� 8.
TL;DR: Small blocks of heterochromatin were found in these 4 species and the karyotypic characteristics of these species were discussed in comparison with other species and populations of Perciformes.
Abstract: Specimens of 4 marine fish species 3 from genus Trachinotus, T. carolinus, T. falcatus, T. goodei, and 1 from genus Selene, S. vomer belonging to the family Carangidae (Perciformes) were analyzed. All the specimens analyzed inhabit the South/Southeast coast of Brazil, and were sampled from the locality Sao Sebastiao, SP. The 4 species presented 2n=48 chromosomes, being the chromosome formula for Selene vomer 46A+2ST, T. carolinus 8MSM+40A, T. falcatus 38A+10MSM and T. goodei 4MSM+44A chromosomes. The 4 species presented 1 pair of NORs. Small blocks of heterochromatin were found in these 4 species. The karyotypic characteristics of these species were discussed in comparison with other species and populations of Perciformes already analysed.
TL;DR: Cytological studies were made in hybrids between S. spontaneum L clone Iritty-2 and Erianthus arundinaceus and Jesweit clone IK 76-99, where certain syncytes had very high number of chromosomes in the form of bivalent at diakinesis and metaphase I, with nearly 80 to more than 600 bivalents.
Abstract: Cytological studies were made in hybrids between S. spontaneum L clone Iritty-2 (2n=64) and Erianthus arundinaceus (Retz.) Jesweit clone IK 76-99 (2n=60). The chromosome number of 19 hybrids ranged from 2n=78 to 86. Predominantly bivalent formation was observed at diakinesis and metaphase I stages in pollen mother cells of all the hybrids. At later meiotic stages abnormalities such as lagging chromosomes, multipolar spindles, abnormal planes of cytokinesis and micronuclei were present. In one hybrid CYM 04-391 with chromosome number 2n=80, the pollen mother cells had cytomixis and syncyte formation in the prophase stage. Certain syncytes had very high number of chromosomes in the form of bivalents at diakinesis and metaphase I, with nearly 80 to more than 600 bivalents. Fertile pollen was observed in few anthers of CYM 04-391 and the pollen size variation was high in it compared to that in the other similar hybrids.
TL;DR: Under the conditions used, A. populnea leaves extract did not induce decrease in mitotic index anddid not induce a statistically significant increase in the mean number of micronucleated polychromatic erythrocytes or chromosome aberrations in the bone marrow cells of Wistar rats.
Abstract: Summary The clastogenic effect of the A. populnea leaves extract was tested in vivo on bone marrow cells of Wistar rats by evaluating the induction of chromosome aberrations and micronuclei induction on polychromatic erythrocytes. The extract was administered by gavage at doses of 300, 600 and 900 mg/kg body weight. Experimental and control animals were submitted to euthanasia 24 h after the treatment. Under the conditions used, A. populnea leaves extract did not induce decrease in mitotic index and did not induce a statistically significant increase in the mean number of micronucleated polychromatic erythrocytes or chromosome aberrations in the bone marrow cells of Wistar rats.
TL;DR: Genomic DNA was isolated from leaves of five species of stylo using CTAB and SDS based extraction buffer ‘S’ method, which yielded high molecular weight DNA (>30 kb).
Abstract: Genomic DNA was isolated from leaves of five species of stylo (Stylosanthes scabra, S. hamata, S. seabrana, S. humilis and S. viscosa), a range fodder legume using CTAB and SDS based extraction buffer ‘S’ method. Ethanol was used as leaf fixing solution instead of grinding in liquid nitrogen, which yielded high molecular weight DNA (>30 kb). DNA quality and quantity were comparable to those isolated with liquid nitrogen. Isolated DNA was suitable for RAPD, sequence tagged site (STS) and restriction enzyme digestion. This method does not require liquid nitrogen for fixation, grinding, or storage at −80°C, making it advantageous over other common protocols.
TL;DR: Fluorescence in situ hybridization using an Arabidopsis-type telomeric sequence (TTTAGGG)n probe to the mitotic chromosomes of Haplopappus gracilis revealed the presence of Interstitial Telomere-like Repeats (ITRs) in at the subdistal position of the long arm of both chromosome pairs.
Abstract: Fluorescence in situ hybridization (FISH) using an Arabidopsis-type telomeric sequence (TTTAGGG)n probe to the mitotic chromosomes of Haplopappus gracilis (n=2) revealed the presence of Interstitial Telomere-like Repeats (ITRs) in at the subdistal position of the long arm of both chromosome pairs (1g and 2g). The H. gracilis genome (n=2) is generally thought to reconstitute from the n=4 complement of the allied species, H. ravenii. The sites we identified by FISH are in close proximity to the chromosomal rearrangement fusion points. This evidence supports the hypothesis that the karyotype of H. garacilis evolved from that of H. ravenii due to chromosome breakage and the subsequent end-to-end chromosome fusion.
TL;DR: From the G-banding and high-resolution technique, the numbers of bands and locations in the pileated gibbon were 183 and 236 respectively, each chromosome pair could be clearly differentiated.
Abstract: Standardized karyotype and idiogram of the pileated gibbon (Hylobates pileatus) Nakhon Ratchasima Zoo, Thailand was studied. Blood sample were taken from 2 females and 2 males. After standard whole blood lymphocyte culture at 37°C for 72 h in the presence of colchicine, the metaphase spreads were performed on microscopic slides and air-dried. G-banding and high-resolution technique were applied to stain the chromosomes. The results showed that the number of diploid chromosomes of pileated gibbon was 2n (diploid)=44. The type of autosomes were 30 metacentric, 10 submetacentric and 2 acrocentric chromosomes, with X and Y chromosome being submetacentric and acrocentric chromosome, respectively. From the G-banding and high-resolution technique, the numbers of bands and locations in the pileated gibbon were 183 and 236 respectively, each chromosome pair could be clearly differentiated.
TL;DR: The chromosome complements of the snakehead, Channa punctatus, were examined using restriction endonucleases like Eco RI, Hind III, Hinf I and Alu I to indicate a possible role of restriction end onucleases as a tool for cytogenetic characterization of fishes.
Abstract: Restriction endonucleases have been shown to digest fixed fish chromosomes, inducing specific and reproducible banding pattern. In the present paper the chromosome complements of the snakehead, Channa punctatus, were examined using restriction endonucleases like Eco RI, Hind III, Hinf I and Alu I. Among them Hind III and Hinf I are capable of producing G band like longitudinal bands. The results indicate a possible role of restriction endonucleases as a tool for cytogenetic characterization of fishes.
TL;DR: Karyotype analyses of 3 Garra species, G.Gotyla gotyla (Gray), G. kempi Hora and G. lissorhynchus (McClelland) from Arunachal Pradesh, India, are presented.
Abstract: Karyotype analyses of 3 Garra species, G. gotyla gotyla (Gray), G. kempi Hora and G. lissorhynchus (McClelland) from Arunachal Pradesh, India, are presented. All the 3 species have a diploid chromosome number of 2n=50, but different karyotype formulae. The species-specific karyotypes were observed in the 3 species. It was also tried to draw a possible phylogenetic relationship among the 3 species.
TL;DR: The karyotypic features suggest for placing the 2 forms in at least different taxonomic variety, since 2 forms possessed distinct centromeric formulae and CMA-banded karyotypes, they could be characterized authentically in these methods.
Abstract: Differential staining with Giemsa, CMA and DAPI was compared in 2 forms of Anabas testudineus (non-spotted and spotted form). The somatic chromosome number of these forms was determined as 2n=46. The range of chromosomal length of non-spotted form and spotted form was 1.86–5.33 μm and 1.60–5.32 μm, respectively. It indicates the gradual decrease in chromosome length of both the forms. The centromeric formulae were 14 m+32 t in non-spotted form and 6 m+40 t in spotted form. More telocentric chromosomes are present in spotted form, thus it is relatively advanced. Facultative heterochromatins were found in the spotted form, it was absent in non-spotted 1. Only one CMA-band was found in non-spotted form, whereas 4 CMA-bands present in the spotted form. Absence of CMA-positive band in a member of pair VI indicates a small deletion of GC-rich repeats in the non-spotted form. The percentage of GC-rich repeats is much more in spotted form. Neither DAPI positive nor negative band could be detected in any form. Since 2 forms possessed distinct centromeric formulae and CMA-banded karyotypes, they could be characterized authentically in these methods. The karyotypic features suggest for placing the 2 forms in at least different taxonomic variety.