scholarly journals Orcein and Fluorescent Banding Analysis of Two Floral Types of Catharanthus Roseus L.

2020 ◽  
Vol 29 (2) ◽  
pp. 219-227
Author(s):  
Tanusree Datta ◽  
Meghla Saha Pinky ◽  
Chandan Kumar Dash ◽  
Kazi Nahida Begum

Two floral types of Catharanthus roseus L. viz. pink and white were studied through differential staining with orcein, CMA and DAPI for cytogenetical characterization and to assist towards updating their taxonomical status and evaluating chromosomal diversity between them. "Simple Chromocenter Type" of interphase nuclei was observed with some darkly stained small heterochromatic regions throughout the nuclei. Most of the prophase chromosomes of Catharanthus roseus (pink and white) were "Continuous Type" and a few were "Gradient Type". Although these two floral types possessed 16 metacentric chromosomes in somatic cells, they showed variation in fluorescent banding pattern considering the modification of GC- and AT-rich repetitive segments. Taking into account all the parameters of both the floral types of C. roseus showed strict symmetric karyotype as well as primitive nature. Therefore, the combined data of differential staining provide information to make comments on their chromosomal status with cytogenetical characterization and also create a baseline for future research. Dhaka Univ. J. Biol. Sci. 29(2): 219-227, 2020 (July)

2019 ◽  
Vol 43 (1) ◽  
pp. 1-9
Author(s):  
Chandan Kumar Dash ◽  
Md Harun Ar Rashid ◽  
Syeda Sharmeen Sultana ◽  
M Oliur Rahman

Karyomorphological characters were investigated in four floral variants of Impatiens balsamina L. viz. white, pink, violet and red for proper characterization and inferring relationships among them. All four floral variants of I. balsamina were found to possess 2n = 14 chromosomes, and ‘Simple Chromocenter Type’ of interphase nuclei was observed in all variants with many small heterochromatin blocks after orcein staining. ‘Continuous Type’ of prophase chromosomes was found in red variant, whereas both ‘Continuous and Gradient Type’ were found in other three variants. The red variant could easily be distinguished from the remaining three variants by total chromosome length, centromeric formula, average chromosome length, total form value, and karyotype asymmetry plus symmetry index. Based on karyomorphology, the white, pink and violet variants of I. balsamina were found very closely related and constituted with similar genome, whereas red variant was found to possess slightly modified genome and distinct from other three floral variants. Journal of Bangladesh Academy of Sciences, Vol. 43, No. 1, 1-9, 2019


2018 ◽  
Vol 27 (2) ◽  
pp. 175-181
Author(s):  
Chandan Kumar Dash ◽  
Sheikh Shamimul Alam ◽  
Syeda Sharmeen Sultana

Karyomorphological features of Justicia adhatoda L. were investigated in this study after differential staining with orcein, CMA and DAPI for proper characterization. In this species "Simple Chromocenter Type" of interphase nuclei was observed with many small heterochromatin blocks after orcein staining. Prophase chromosomes showed "Interstitial Type" of staining pattern which indicated the tendency of aggregation of heterochromatin in interstitial regions of chromosome. This species was found to possess 2n = 34 metacentric chromosomes. The total length of 2n chromosome complement was 132.17 μm. Individual chromosome length ranged from 2.57 to 5.43 μm. The relative length of each chromosome ranged from 0.02 to 0.04. A total of seven CMA-positive bands were observed in this species whereas no band was found after DAPIstaining. This result suggested the absence of AT-rich portions and occurrence of GC-rich portions in the respective banded chromosomes. Except 2n chromosome number, the other karyological and fluorescent banding information probably was the first report for this species and it might help to enhance the chromosomal data base with detailed karyomorphological information of this plant species in Bangladesh. Dhaka Univ. J. Biol. Sci. 27(2): 175-181, 2018 (July)


2021 ◽  
Vol 45 (1) ◽  
pp. 27-35
Author(s):  
Ashma Ahmed Warasy

Karyotype analyses are required for the identification, characterization, and genetic improvement of any organism. Alocasia macrorrhizos (L.) G. Don. was investigated cytogenetically to determine the karyotypic features. Complex chromocenter type, of interphase nuclei, and gradient type of prophase chromosomes were found in this study. Alocasia macrorrhizos was found to possesses 2n=28 chromosomes. The total length of the 2n chromosome complement was recorded as 98.83±1.39 μm. The range of chromosomal length was 2.50±0.10-4.70±0.10 μm. A gradual decrease in chromosomal length was observed. The total form (TF%) value was found to be 43.58%, Karyotype symmetry index (Syi %) was 77.00 % and karyotype asymmetry index (AsK %) was 56.66%. The centromeric formula was 18m+4sm+2ac, representing asymmetric karyotype. In DAPI banding, the 1.48% positive banded region indicates the lower amount of AT rich repeats in this material. Therefore, Alocasia macrorrhizos could be authentically characterized through karyotype analysis. J. Bangladesh Acad. Sci. 45(1); 27-35: June 2021


Author(s):  
Avi Ostfeld

Water distribution systems least cost pipe sizing/design is probably the most explored problem in water distribution systems optimization. Attracted numerous studies over the last four decades, two main approaches were employed: decomposition in which an “inner” linear programming problem is solved for a fixed set of flows/heads, while the flows/heads are altered at an “outer” problem using a gradient or a sub-gradient type technique; and the utilization of an evolutionary optimization algorithm (e.g., a genetic algorithm). In reality, however, from a broader perspective the design problem is inherently of a multiobjective nature incorporating competing objectives such as minimizing cost versus maximizing reliability. This chapter reviews some of the literature on single and multiobjective optimal design of water distribution systems and suggests a few future research directions in this area.


1970 ◽  
Vol 38 (1) ◽  
pp. 111-113 ◽  
Author(s):  
Syeda Sharmeen Sultana ◽  
ANM Rubaiyath Bin Rahman ◽  
Sheikh Shamimul Alam

Many prominent darkly stained heterochromatic blocks were found in the interphase nuclei of Rauvolfia serpentina following orcein staining. The prophase chromosomes of this species became stained homogeneously throughout the entire length. This species was found to possess 2n = 20 metacentric chromosomes revealing symmetric karyotype but if the chromosome length (6.67 - 3.17 μm) is considered, it indicates asymmetric karyotype. Total GC-rich region was 15.62% of the total chromatin length. Eight CMA-positive bands on different locus revealed the accumulation of GC-rich repeats. The two entirely CMA-banded chromosomes were so unique that could be used as marker for this species. Key words: Karyotype; Rauvolfia serpentina; Fluorescent banding DOI: 10.3329/bjb.v38i1.5133 Bangladesh J. Bot. 38(1): 55-63, 2009 (June)


2014 ◽  
Vol 57 (3) ◽  
pp. 317-327
Author(s):  
Elżbieta Weryszko-Chmielewska

The number and morphology of <em>Callisia elegans</em> Alexand. chromosomes were studied employing staining with acetic carmine and differential Giemsa staining. It was found that its karyotype was 2n = 12 chromosomes, whose lengths fell in the range of 16.8 to 8.8 µm. The chomosomes, arranged in order of length, were classified respectively to types: sm, t, t, t, t, st. The distribution of C-banding is given for this karyotype. The presence of microsatellites on the long and short arms was found in the chromosomes of the second pair. Frequently there were 4 nucleoli of unequal size in interphase nuclei. In many cells, lower numbers of nucleoli (3-1) were seen which was -probably due to their fusion. The maximum number of nucleoli corresponded to the number of nucleolar organizers accompanying the satellites.


CYTOLOGIA ◽  
1996 ◽  
Vol 61 (4) ◽  
pp. 383-394 ◽  
Author(s):  
Shamimul Alam Sheikh ◽  
Katsuhiko Kondo

2019 ◽  
Vol 54 (4) ◽  
pp. 283-288
Author(s):  
MS Rahman

In the present study, karyomorphological features of Enhydra fluctuans Lour. were investigated. Orcein-staining was used for the authentic chromosomal characterization and identification. In E. fluctuans ‘Simple Chromocenter Type’ of interphase nuclei was observed with many small heterochromatin blocks after orcein staining. Prophase chromosomes showed ‘Gradient Type’ with orcein staining. This species was found to possess 2n=10x=110 with basic chromosome number x=11 and this is probably the first report for this species. The centromeric formula of this species was ‘38m+70sm+2ac’. The above features indicated that E. fluctuans is an advance polyploid with asymmetric karyotype. The total chromatin length (2n) was 295.92 μm. Individual chromosome length ranged from 1.84-4.26 μm. The relative length of each chromosome ranged from 0.006-0.014. The above mentioned data will be useful for karyomorphological characterization of E. fluctuans from Bangladesh. Bangladesh J. Sci. Ind. Res.54(4), 283-288, 2019


2003 ◽  
Vol 60 (3) ◽  
pp. 449-466 ◽  
Author(s):  
P. ZHOU ◽  
Z.-J. GU ◽  
M. MÖLLER

The morphological characteristics of mitotic interphase, prophase and metaphase nuclei were analysed for 21 taxa in 14 genera from three different tribes of subfamily Cyrtandroideae (Gesneriaceae) from Asia. Interphase nuclei were classified into three categories: (1) complex chromocentres, as in Ancylostemon, Briggsia, Briggsiopsis, Chirita, Loxostigma, Lysionotus, Oreocharis, Petrocosmea, Raphiocarpus and Whytockia, (2) simple chromocentres, as in Paraboea and Rhabdothamnopsis, and (3) round prochromosomes, as in Anna and Didymocarpus. Species with complex chromocentres seem to be most common among all three tribes. The data further indicate that tribe Didymocarpeae is cytologically much more heterogeneous than other tribes, which accords with the diversity in morphological characters. Three types of chromosome condensation pattern during mitotic prophase were observed, here described as interstitial, gradient and proximal. Except for Ancylostemon, exhibiting a proximal type, and Lysionotus and Whytockia possessing a gradient type, all other species analysed to date exhibit the interstitial type. Our study also reports the chromosome numbers of 12 species in 10 genera of subfamily Cyrtandroideae from China and Vietnam; 11 of these counts are new.


Author(s):  
Anthony J. Godfrey

Aldehyde-fixed chick retina was embedded in a water-containing resin of glutaraldehyde and urea, without dehydration. The loss of lipids and other soluble tissue components, which is severe in routine methods involving dehydration, was thereby minimized. Osmium tetroxide post-fixation was not used, lessening the amount of protein denaturation which occurred. Ultrathin sections were stained with 1, uranyl acetate and lead citrate, 2, silicotungstic acid, or 3, osmium vapor, prior to electron microscope examination of visual cell outer segment ultrastructure, at magnifications up to 800,000.Sections stained with uranyl acetate and lead citrate (Fig. 1) showed that the individual disc membranes consisted of a central lipid core about 78Å thick in which dark-staining 40Å masses appeared to be embedded from either side.


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