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

Genotypic Variability in Callus Induction and Plant Regeneration Through Somatic Embryogenesis of Five Deepwater Rice (oryza Sativa L.) Cultivars of Bangladesh

L. Khaleda
Department of Genetic Engineering, University of Chittagong, Chittagong-4331, Bangladesh.

M. Al-Forkan
Department of Genetic Engineering, University of Chittagong, Chittagong-4331, Bangladesh.

Abstract/ Executive Summary:

Experiments were carried out to induce embryo genic callus and plant regeneration from five different deep water rice cultivars. Using mature embryos as explant, all the cultivars demonstrated high callus induction and plant regeneration frequencies. When coleoptile and root segments used as explants, they had low frequencies of embryo genesis. Depending on different genotypes, the best plant regeneration was obtained on LS based medium supplemented with 2 mg I-¹ BAP + 1.5 mg I-¹, 4-0. Large variabilities in callus growth and plant regeneration potential were revealed among the cultivars tested. Cultivar HA-8 formed a high frequency (78%) of callus than that of other cultivars. In contrast cv. HA-1 produced the highest percentage (72%) of plant regeneration. The callus growth potential was not correlated with the plant regeneration potential. Coleoptiles and root segments produced calli, which did not develop any shoot bud in regeneration media. Moreover, the calli turned blackish, watery and translucent after 25-28 days of culture. It is clear that mature seed scutellum (MSS) is the best explant for callus induction and plant regeneration.

Keywords: Callus, Regeneration, Embryogenesis, Genotypic variability, Deepwater rice

Location: BRRI regional station and Comilla and Hatiya

Start Date:

End Date:

Program Area: Crop-Soil-Water Management

Commodity: Rice

Objectives:

To induce embryo genic callus and plant regeneration from five different deep water rice cultivars.

Methodology:

Five deep water rice cultivars namely, Habiganj Aman-1, Habiganj Aman-2 and Habiganj Aman-8 released from BRRI regional station and Murabajal and Gheoch land races grown in the coastal saline region of Comilla and Hatiya were used in this study as source of explants. Dehusked seeds from five deep water rice were placed in two basal media MS (Murashige and Skoog 1962) and LS (Linsmaier and Skoog, 1965). Both the basal media were supplemented with 2 mg l^-1 2,4-D, 0.1% CH, 0.5 mg l ^-1 BAP and 0.5 mg l ^-1 Kinetin on the basis of requirement and also 30 g l^-1 sucrose added and media were solidified with 0.8% (w/v) agar. Three explants, MSS, coleoptiles and root segments from different rice cultivars were used for callus induction. Prior to culture, dehusked seeds were sterilized with 0.2% (w/v) HgCl ₂ solution. In case of coleoptile segments, germinating seedling in the hormone free MS medium were taken out from culture vessels for dissection after 4 to 5 days culture, and coleoptile segments were separated from endosperm (scutella) by cutting of the base of coleoptiles. The tips of the coleoptiles were removed. The separated whitish hollow and tubular coleoptiles (1-1.5 cm long) without any internal organs were used for culture. Seedling roots (10-12 days post germination) were excised and cut into 1-1.5 cm sections. For callus induction nine sterilized seeds per petri dish were inoculated in 20 ml callus induction medium and five replications for each treatment were maintained. Finally seed inoculated petri dish was sealed with parafilm paper and incubated in the dark chamber at 26 ± 2°C in the culture room (Figure 1a). After 14 days, shoots and roots were excised (for MSS) and the scutella derived calli were transferred to fresh medium and maintained for a further 14 days under the same growth conditions. On the other hand, after 21 days, induced callus from coleoptile and root segments were sub-cultured on the same medium for further 21 days. Calli were transferred to MS and LS basal media supplemented with 2 mg l -1 BAP, 0.5 mg l ^-1 kinetin, 1.5 mg l ^-1 2,4-D and 1.5 mg l ^-1 NAA as required and 30 g l ^-1 (w/v) sucrose. The medium was gelled with 0.8% (w/v) or 1% (w/v) agar. During the course of sub-culture, explants-produced embryogenic calli were selected and transferred to MS and LS based regeneration media with 1% (w/v) agar. The calli, which turned to pale yellowish in colour, watery, blakish and shown dry, were rejected. The shoot regeneration frequencies were recorded 20 days after transfer of tissue to regeneration medium. When regenerated plants (MSS derived) of five cultivars were 8-10 cm in height, they were cultured on MS + 1.5 mg l ^-1 NAA supplemented rooting medium. Well developed plant lets (after 20-25 days) were taken out from rooting medium, their roots were washed with tap water to remove excess agar and were grown in natural conditions.

Source of Information: African Journal of Biotechnology Vol. 5 (16), pp. 1435-1440, 2006, ISSN 1684–5315

Article Link (Online Journal): http://www.academicjournals.org/AJB

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

It can be concluded that the in vitro protocol described here could be used for efficient plant regeneration of deep water rice cultivars followed by useful gene transformations.

Knowledge Management: Journal