• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.6
• /
• pp.757-767
• /
• 1995

This experiment was done to determine the optimum concentration of IAA for root development in plants regenerated from the callus culture of barley embryos. Two concentrations of 2,4-D, 3ppm and 5ppm selected as an optimum among five different concentrations in the previous experiment were used for callus induction and proliferation in this experiment. For callus induction, 3ppm of 2,4-D produced 35.6% in immature embryos and 4.4% in mature embryos, while 5ppm gave 33.8% in immature and 5.6% in mature embryos. Out of 320 immature embryos cultured, 111 embryos were induced to calli and 684 plants were produced from them, while only 16 embryos were induced to calli from 320 mature embryos and 92 plants were restored. The rates of callusing and plant regeneration were 34.7%, 214% in immature embryos and 5.0%, 28.7% in mature embryos, respectively. The average root lengths and root numbers of plants restored from callus at five different IAA concentrations of 0ppm, Ippm, 5ppm, l0ppm and 30ppm were 7.9mm, 3.6; 18.4mm, 5.2; 16.1mm, 3.9; 8.5mm, 3.5 and 6.4mm, 3.4, while plants directly obtained from mature embryos were 14.8mm, 4.9; 4.9mm, 3.6; 4.3mm, 3.1; 3.6mm, 2.6 and 3.2mm, 2.1, respectively. Therefore, 1ppm gave the best result for the root. promotion in callus, whle 0ppm, a control, gave the largest root developmemt in embryos. High concentration of lAA(30ppm) in callus and any exogeneous supplement of lAA in embryos negatively affected to the root lengths and root numbers. Genotypic effect was also observed in given four varieties, Bruce, Klages, Olbori and Albori. For chromosome doubling, when 0.1% colchicine was applied on 428 plants under three different conditions such as air circulation, temperatures and growth stages, 319 plants of doubled haploids were obtained so that the rate was 74.5%

• Applied Chemistry for Engineering
• /
• v.17 no.6
• /
• pp.619-624
• /
• 2006

This study was performed to investigate the formation process of calcium sulfate ${\alpha}$-hemihydrate from FGD gypsum produced at thermal power plant burning bituminous coal. The experimental results showed that calcium sulfate $\alpha$-hemihydrate with a large aspect ratio was produced in the temperature range of $120^{\circ}C$ and $140^{\circ}C$ in the absence of additives through dissolution-recrystallization mechanism. It was also observed that addition of Na-succinate as a catalyst changed crystal shape from acicular to prismatic, resulting in decreased water/powder ratio down to 33%. Optimum concentration of Na-succinate was 20mM. It was confirmed that the optimum moulding pressure and moisture content of moulded body from FGD gypsum were $30kg_f/cm^2$ and between 10% and 15% respectively, which prevent moulded body from collapsing and maximize the capillary effect by given pore volume while autoclaving.

• FLOWER RESEARCH JOURNAL
• /
• v.16 no.1
• /
• pp.12-16
• /
• 2008

This study was carried out to produce haploid plants to verify a systematic breeding program and genetic analysis. Effect of developmental stage of pollen grains and pre-treatment temperature on production of haploid plants was investigated. Microscopic investigation of the explants (Lilium Asiatic hybrid 'reamland' revealed that the length of flower bud at 23.0-24.9, 25.0-26.9, and 27.0-28.9 mm long coincided with tetrad, uninucleate, and binucleate, respectively. When the efficiency of the anther culture from microgametogenetic stages was tested, late uninucleate to early binucleate stage, having the length of 23.0 to 28.0 mm long flower bud, was the best. The frequencies of the callus induction and plant regeneration from the stage mentioned above were 17.8 and 6.7%, respectively. When calli were cultured on the MS medium containing picloram and zeatin at $25^{\circ}C$, shoots were obtained. Roots of regenerated plantlets were confirmed as haploid through an microscopic observation.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.1
• /
• pp.74-78
• /
• 1991

This experiment was conducted to know the effects of mutagen treatments on callus induction, plant regeneration and their ploidy in the anther culture of wheat. The winter wheat cultivars, 'apos;and 'apos;Wonkwang'apos;, were treated at the mid or late-uninucreate stage under 4 different doses (100, 200, 500 and 1,000 rad.) of X-ray and 3 different levels(0.1, 0.2 and 0.3 mole) of Ethyl Methane Sulphonate. The anthers treated were set on the C$\_$17/medium for callus induction, and callus induced was transfered to 1/2 MS medium for plant regeneration. The mutagen treatments inhibited the callus induction but increased the plant regeneration in the callus which were induced from the anther set on the medium for the long time of 60 to 80 days. Also, the chromosome number to the regenerated plant varied largely by increasing of haploid plants(n=3x=21) and by occurring of aneuploidy having n=20 and n=22 of chromosome number.aried largely by increasing of haploid plants(n=3x=21) and by occurring of aneuploidy having n=20 and n=22 of chromosome number.

• Applied Chemistry for Engineering
• /
• v.8 no.5
• /
• pp.822-829
• /
• 1997

When $Al_2(SO_4)_3$ as an accelerator was added to $\beta$-hemihydrate gypsum, the setting time, mobility and compressive strength properties of $\beta$-hemihydrate gypsum were examined with the adding of two types grounded gypsum crushed by ball mill. By 15wt% adding of 7% $Al_2(SO_4)_3$ dilute solution, the setting time of $\beta$-hemihydrate gypsum was sharply accelerated than that of non-added $\beta$-hemihydrate gypsum. When ground phospho gypsum(PG) and chemical gypsum(CG) were added to $\beta$-hemihydrate gypsum, the initial and final setting time of $\beta$-hemihydrate gypsum were accelerated markedly with the increasing of grinding time and added amount of ground phospho gypsum. Especially, this trend largely presented when ground phospho gypsum was added to $\beta$-hemihydrate gypsum. The compressive strength of $\beta$-hemihydrate gypsum added by ground phospho and chemical gypsum was largely increased at initial curing time such as 1, 3 days. Particularly, the compressive strength of $\beta$-hemihydrate gypsum added by ground phospho gypsum was increased by 15~20% than that of ground chemical gypsum.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.25 no.4
• /
• pp.90-102
• /
• 2024

Haploid/double haploid plants developed from isolated microspores can significantly accelerate plant breeding. Haploid plants can naturally double their chromosomes to create a pure homozygous line of diploid plants. We present a method for producing embryos from isolated microspores of hot peppers (Capsicum annuumL.). We analyzed the polyploidization levels of the regenerated plants. The donor plants produced the optimal stage of microspores following short-term growth under low-intensity light, which resulted in high rates of embryogenesis and cotyledonary embryogenesis. To find an efficient culture method, liquid, doubled-layer, and 2-step cultures were tested. Liquid culture yielded the highest number of embryos, whereas the highest efficiency for cotyledonary embryogenesis was afforded by the doubled-layer culture. When normal cotyledonary embryos were transplanted onto a regeneration medium, they developed into complete plants. From these, 208 plants were tested via flow cytometric analysis, and 35.6% and 72.7% of the chromosomes from the Milyang-jare and LV2319 genotypes, respectively, were found to be spontaneous double haploids. These results are the same as those obtained on analyzing horticultural characteristics, including the size of leaves and the size and shape of fruits. The present study provides information on the practical application of isolated microspore culture of hot peppers, factors that affect embryogenesis, and methods for polyploidy testing.

• Journal of the Korean Society of Tobacco Science
• /
• v.4 no.2
• /
• pp.31-36
• /
• 1982

The field evaluation were conducted on dihaploid progenies derived from anther culture of F1 plant of Drama x Sohyang (N. tabacum L.) The mean values of agronomic and chemical traits of dihaploids such as Nicotine, length/width, plant height, Leaf length, leaves per plant and Yield were greater than those of tar parents. The correlation coefficient of dihaploids were similar to those of conventional lines and varieties. In path analysis, in relating yield components to yield, leaves per plant and leaf width had a direct effect on Yield, but the other components such as plant height, leaf length and days to flowering influenced Yield indirect way.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.18 no.4
• /
• pp.43-48
• /
• 1981

The Cdse TFTs with SiO gate insulator layer have been fabricated with vacum evaporatim technique. The effects of semiconductor thickness and drain-source channel length on the electrical propertis have been investigated. The TFTs with 1000$\AA$ SiO insulator, 1500 $\AA$ CdSe semiconductor layer and 40$\mu$m chammel length showed the best characteristics.

• Korean Journal of Plant Tissue Culture
• /
• v.22 no.1
• /
• pp.13-17
• /
• 1995

In order to induce haploid plant through pollen culture, pollens of Paeonia albiflora were cultured on MS liquid medium The development of micospore through pollen culture was examined The effect of low temperature (5$^{\circ}C$, 10 days) pretreatment on callus induction and embryogenesis in pollen culture was not evident Calli derived from pollen gave rise to globular embryos when transferred onto solid medium containing 0.5 mg/, 2,4-L. The effect of low temperature pretreatment and medium. combination to pollen viability was unrecognized. Pollen viability was reduced as the culture proceeded.

• Microbiology and Biotechnology Letters
• /
• v.24 no.6
• /
• pp.726-732
• /
• 1996

To improve the fermentation characteristics(such as starch-degradability, ethanol tolerance, sugar and high-temperature tolerance) of recombinant haploid yeast Saccharomyces diastaticus K114, hybridization technique was used. The hybridization partner was S. diastaticus 1177 which had good glucoamylase activity and fermentabi- lity. The best hybrid HH64 showed improved ethanol tolerance, sugar and high-temperature tolerance. Especia- lly, the starch-fermentability was significantly improved, since the hybrid produced 1.60% (w/v) ethanol from 4% (w/v) starch, while the recombinant haploid K114 produced 1.30% (w/v) ethanol. The optimum temperature and pH for the starch-fermentation by the hybrid HH64 was 30$\circ$C and 5, respectively. The hybrid yeast HH64 produced 7.5% (w/v) ethanol directly from 20% (w/v) starch.