Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Karyotype Comparison in Two Varieties of Vigna Mungo L. After Staining with Orcein and Cma

SHEIKH SHAMIMUL ALAM*
Department of Botany, University of Dhaka, Dhaka-1000, Bangladesh

MEHER NIGAR MAHBUB
Department of Botany, University of Dhaka, Dhaka-1000, Bangladesh

Abstract/ Executive Summary:

Two varieties of Vigna mungo viz. Barimash-1 and Barimash-3 were cytologically studied after staining with orcein and CMA. Both the varieties were found to possess 2n =22 metacentric chromosomes. Total length of diploid complements and range of chromosome length were more or less same in the two varieties. The orcein stained interphase nucleus of Barimash-1 had three big heterochromatic blocks, whereas Barimash-3 possessed several small heterochromatins. The orcein stained prophase chromosomes of Barimash-1 was darkly stained throughout the entire length. The gradual staining of prophase chromosomes were found in Barimash-3. The CMA stained interphase nuclei and prophase chromosomes of these two varieties were different. Sixteen entirely CMA banded chromosomes were found in Barimash-1. The percentage of GC-rich areas was 56.20. In Barimash-3, 11 entirely, 4 terminal and 4 centromeric fluoresced banded chromosomes were found. The percentage of GC-rich areas was 63.40. Although the two varieties showed similar conventional karyotypes, mark differences exist in their fluorescent karyotypes and the properties of interphase nuclei and prophase chromosomes. Therefore, these two varieties could be characterized with the help of modern cytological techniques.

Keywords: Karyotype, Vigna mungo, Blackgram, CMA

Location: Department of Botany, University of Dhaka, Dhaka

Start Date:

End Date:

Program Area: Crop-Soil-Water Management

Commodity: Black gram

Objectives:

The present research programme was undertaken to characterize the karyotypes of two varieties of Vigna mungo after staining with orcein and CMA.

Methodology:

Seeds of two varieties of Vigna mungo viz. Barimash-1 and Barimash-3 were collected from Bangladesh Agriculture Research Institute (BARI). The plants were grown and maintained in the Botanical garden, Department of Botany, University of Dhaka. Healthy roots were collected and pretreated in 0.002 M 8-hydroxyquinoline for 2.20 h at room temperature (25º C) followed by fixation in 45% acetic acid for 15 min at 4ºC. The root tips were hydrolyzed for 6 sec at 60º C in a solution containing 1 N HCl and 45% acetic acid (2:1) and stained with 1% aceto-orcein. For CMA staining, after hydrolysis the root tips were squashed with 45% acetic acid. The cover glasses were removed quickly and air-dried for at least 24 h before study. The slides were incubated in McIlvaine’s buffer (pH 7.0) for 10 min followed by Distamycin A treatment (0.1 mg/ml). Slides were mildly rinsed in McIlvaine’s buffer supplemented with 5 mM MgSO₄ for 10 min. One drop of CMA (0.1 mg/ml) was placed on each slide and kept for 10 min in a humid chamber. The slides were mounted in 50% glycerol and kept overnight at 4ºC. The slides were examined under a Nikon fluorescent microscope with blue-violet filter cassette

Source of Information: Bangladesh J. Bot. 36(2): 167-170, 2007 (December)

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

Polymorphisms regarding CMA banding were found in pair I and XI of Barimash-1 and pair II, III and V of Barimash-3. Here one member of the pair showed CMA banding and another did not. The polymorphism of CMA-positive banding pattern of two varieties indicates the probable occurrence of minute structural aberration and presence of different heterochromatins. The banded chromosomes were stable and made each karyotype unique. Therefore, fluorescent banding technique could help in differentiating the two varieties of V. mungo used during this investigation.

Knowledge Management: Journal