• Asian Journal of Turfgrass Science
• /
• v.12 no.4
• /
• pp.195-202
• /
• 1998

The development of a protocol for high efficiency of embryogenic callus separation, maintenance and plant regeneration from the seeds of zoysiagrass cv. Zenith was studied. Embryogenic callus ratio is absolutely determined by genotype, but by adding high concentration of copper into medium, changing light condition and maintaining callus on initial induction medium for 8∼10 weeks, embryogenic callus can be easily distinguished and its growth can be promoted. There were significant differences among selected callus lines (each from one seed) according to their growth rates and regeneration percentages. Callus pre-treatment with activated charcoal inhibited callus growth, increased the level of precocious germination during culture and promoted shoot cluster formation after transfer to regeneration medium. For long-term callus maintenance, N6AA medium was better than MS medium, because the former inhibited non-embryogenic callus formation and kept vigor of embryogenic callus. The best callus lines Z-(5) has been successfully used for transformation and somaclonal variation selection in our laboratory.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.20 no.1
• /
• pp.19-24
• /
• 2000

This study was camed out in order to establish plant regeneration via seed-derived callus of perennialryegrass.Varietal difference in callus growth and plant regeneration was obvious between two cultivars of perennialryegrass. "Reveille" showed a relatively high capacity for plant regeneration. The MS medium was superiorto SH or Bj in callus formation and plant regeneration. The highest regeneration frequency (60%) from calluswas obtained in presence of 5 mg/ l 2,4-D and 1 mg/ t kinetin. Regeneration response varied among calluscultures initiated from the same cultivar. Regeneration frequency was the most effective in 6 weeks-old calliafter initiation and lost their regeneration capacity gradually over a period of 12 weeks.(Key words : Perennial ryegrass (Lolium perenne L.), Plant regeneration)e L.), Plant regeneration)

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.24 no.3
• /
• pp.265-270
• /
• 2004

Plant regeneration from seed-derived callus of Kentucky bluegrass(Poa pratensis L. cv. Kenblue) was investigated. Callus induced on the medium supplemented with 2 mg/L 2,4-D and 0.2 mg/L BAP showed highest frequency of plant regeneration on the regeneration medium supplemented with 1 mg/L NAA and 5 mg/L kinetin. Callus induced in the dark condition showed higher regenerability than that induced in the dim light. MS medium was better than N6 and B5 medium in enhancing plant regeneration. Maltose was superior to sucrose in plant regeneration as carbon source in the medium.

• Journal of Plant Biotechnology
• /
• v.39 no.3
• /
• pp.169-174
• /
• 2012

Quantitative trait loci (QTLs), which were related to the ability of callus induction and plant regeneration in seed culture of rice, were analyzed using a mapping population from a cross between the rice cultivars 'Samgang' (tongil type) and 'Nagdong' (japonica). A tongil type rice cultivar, 'Samgang' showed lower frequency (20%) of plant regeneration than that (35%) of japonica rice, 'Nagdong'. Transgressive segregations were observed for the ability of callus induction and plant regeneration from the seed-derived calli of 58 doubled haploid (DH) lines. The ability of plant regeneration of 58 doubled haploid lines showed a continuous distribution with comparatively wide range (10.0 to 66.7%) of variation. Composite interval mapping analysis was used to identify the QTLs controlling callus induction and plant regeneration ability. Four significant QTLs, qCWS6, qCWS8, qCWS9 and qCWS11, associated with callus weight per seed were detected on chromosomes 6, 8, 9, and 11 with LOD values of 3.30, 2.60, 2.70 and 2.43, explaining 36% of the total phenotypic variation. Three significant QTLs, qPR1, qPR6, and qPR11, for the ability of plant regeneration were located on chromosome 1, 6, and 11 at LOD score of 2.25, 2.15 and 2.55, accounting for 24 % of the total phenotypic variation. The present study should be useful for improving the efficiency of plant regeneration in tissue culture of indica rice by means of marker-assisted selection.

• Korean Journal of Breeding Science
• /
• v.42 no.4
• /
• pp.351-356
• /
• 2010

Brachypodium distachyon is rapidly emerged in biological study and has been currently used as a model system for genetics and functional studies for crop improvement and biofuel production. Phosphinothricin (PPT) has been widely used as a selectable agent, which raises ammonium content and induces toxicity in non-transformed plant cells. However PPT selection is not much effective on Brachypodium callus consequently reducing transformation efficiency. In order to identify the efficient conditions of PPT selection, calli obtained from mature seeds of Brachypodium (PI 254867) were cultured on the callus inducing medium (CIM) or regeneration medium (ReM) containing serial dilutions of the PPT (0, 2, 5, 10, and 15 mg/l) in dark or light condition. Callus growth and ammonium content of each treatment were measured 2 weeks after the treatment. Although callus growth and ammonium content did not show much difference in CIM, slow callus growth and increased ammonium accumulation were found in ReM. No significant difference of ammonium accumulation in response to PPT was found between dark and light conditions. In order to identify major factors affecting increased ammonium accumulation, callus was cultured on the media in combined with phytohormones (2,4-D or kinetin) and carbon sources (sucrose or maltose) containing with PPT (5 mg/l). The highest ammonium content in callus was found in the kinetin and maltose media.

• Journal of Plant Biotechnology
• /
• v.30 no.4
• /
• pp.341-346
• /
• 2003

In an effort to optimize tissue culture conditions for genetic transformation of orchardgrass (Dactylis glomerata L.), an efficient and high-frequency plant regeneration system from seed-derived calli was established. Embryogenic calli induced on MS medium containing 3mg/L 2,4-D and 0.1mg/L BA had significantly improved regeneration ability. Plant regeneration rate was 92％ when embryogenic calli were cultured on N6 medium supplemented with 1mg/L 2,4-D and 3mg/L BA. Among three kinds of medium, MS and N6 medium were optimal for embryogenic callus induction and plant regeneration, respectively. Ho difference in callus induction frequency was observed among four cultivars of orchardgrass, however, "Roughrider" cultivar showed higher regenerability with the frequency of 61％. Addition of maltose to the regeneration medium as a carbon source dramatically increased regeneration frequency up to 69％. A short tissue culture period and high-frequency regeneration system would be beneficial for molecular breeding of orchardgrass through genetic transformation.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.18 no.4
• /
• pp.285-290
• /
• 1998

aThis experiment was carried out to obtain the basic information on some factors affecting callus formation and plant regeneration in seed culture of orchardgrass. Varietal difference in callus growth and plant regeneration was obvious among four varieties of orchardgrass. "Amba" showed a relatively high capacity for plant regeneration. The $N_6$ medium was superior to MS and $B_5$ in callus formation and plant regeneration. The fresh weight of callus was promoted by the increase of dicamba concentration. However, the maximum frequency (30.0%) of plant regeneration was obtained from the callus formed in presence of 3 mg/L dicamba.

• Korean Journal of Plant Tissue Culture
• /
• v.28 no.4
• /
• pp.205-208
• /
• 2001

This study was conducted to improve the regeneration efficiency from seed-derived calli of rice by optimizing the copper concentrations in the media. Mature seeds were cultured on MS medium supplemented with copper sulphate (0 to 5.0 mg/L) and 2 mg/L 2,4-D. Callus growth was influenced by the levels of copper sulphate containing with medium, The addition of copper sulphate (2.5 mg/L) in regeneration medium enhanced dramatically the ability of plant regeneration from seed-derived calli. The mean frequency of plant regeneration of 6 indica rices was 27.4% on medium containing copper sulphate, whereas that of the cultivars on copper-free medium was 2.4%. These results suggest that copper sulphate may have an important role in improving regeneration ability of indica rices.

• Journal of Plant Biotechnology
• /
• v.30 no.2
• /
• pp.151-154
• /
• 2003

This study was conducted to determine the optimal concentrations of plant hormones (2,4-D, picloram, dicamba, NAA, kinetin) and the suitable explants among seeds, hypocotyl, and cotyledons on calls formation and plant regeneration of stevia(Stevia rebaudiana Bertoni). The frequency of cellus formation was higher in the young leaf-explants then the older ones, and in the seeds then the hypocotyls and cotyledons on MS medium with 1mg/L 2,4-D. After transfer of seed-derived stevia callus producing embryogenic callus on plant-regeneration medium, the frequency of plant regeneration from callus was 23.8% in MS medium with 1mg/L NAA and 3mg/L kinetin.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.31 no.3
• /
• pp.211-216
• /
• 2011

The present study was conducted to determine the optimum in vitro conditions for callus induction and plant regeneration from mature seed derived callus of four cultivars of Timothy. In order to investigate the effects of genetic variations of timothy in tissue culture, calli were induced from mature seeds of four varieties, 'Colt', 'Chair', 'Richmond' and 'Hokuo' and plant regeneration frequency was compared. Significant differences were observed among the cultivars in both callus induction and plant regeneration. Genotype 'Colt' consistently performed best in the callus subculture and plant regeneration. The complete plantlets were thereafter transplanted to grow under greenhouse condition. Regenerated timothy plants were morphologically uniform with normal leaf and growth pattern.