• Korean Journal of Plant Resources
• /
• v.36 no.6
• /
• pp.588-596
• /
• 2023

Long-term culture of cell lines is an important issue in in vitro culture and in plant science. In this study, the regeneration ability and ex vitro acclimatization of regenerants were evaluated. The ploidy level of regenerants derived from long-term cultured cell lines was measured in Imperata cylindrica 'Rubra', Poaceae. Adventitious buds (shoots) were successfully induced from five-year-cultured calli on MS medium containing 0.1 mg/L BA or 2.0 mg/L TDZ, combined with 0.01 mg/L auxins (IAA, IBA, NAA and 2,4-D), respectively. Adventitious roots were also induced on MS medium containing 0.01 mg/L auxins (IBA, NAA and 2,4-D), respectively. Interestingly, regenerants with both red and green leaf were successfully obtained when regenerants were cultured on MS medium with 9% sucrose. Regenerants derived from long-term cultured calli were transferred to pots using an optimal acclimatization process and successfully adapted to both pot and soil conditions. Moreover, the ploidy level was measured using calli and regenerants that had been kept on MS medium containing various kinds of plant growth regulators (PGRs).

• Korean Journal of Breeding Science
• /
• v.41 no.3
• /
• pp.213-219
• /
• 2009

This study was carried out to establish breeding system for interspecific hybridization of Lilium using spontaneous meiotic polyploidization of $F_1$ OA hybrid and its progenies. Pollen viability and germination of $F_1$ OA interspecific hybrid showed variation by collection time, indicating that pollen grain in June, which was natural blooming season, had better viability and germination ability than in October. 2n-gametes from spontaneous meiotic polyploidization of OA hybrid were crossed with either diploid Asiatic or Oriental hybrid, and subsequent progenies crossed with Asiatic hybrid as female and OA hybrid as male showed the highest efficiency, where 2x-2x A$\times$OA produced 0.64 plants per cross combination, while 2x-2x, O$\times$OA and 2x-2x, OA$\times$A crosses produced 0.42 and 0.4 plant per ovary, and especially no progeny was obtained in 2x-2x, OA$\times$O cross combination. For the subsequent progeny production, a cross between diploid Asiatic hybrid as female and diploid OA hybrid as male was the best ploidy combination. Ploidy level of subsequent progeny derived from backcross with 2n-gametes of OA hybrid revealed that triploids from 2x-2x OA$\times$A, tetraploids from both 4x-2x, AA$\times$OA and OO$\times$OA, diploid from 2x-2x, O$\times$OA, and diploids or triploids from 2x-2x, A$\times$OA crosses were produced respectively.

• Current Research on Agriculture and Life Sciences
• /
• v.32 no.2
• /
• pp.99-103
• /
• 2014

This study investigated the effects of cryopreserving Chrysanthemum morifolium cv. 'White ND' shoot tips for eliminating viroids. As a result, smaller shoot tips (2-3 LP, 1mm) showed a better survival and regrowth than larger shoot tips (4-5 LP, 1.5mm). The most effective vitrification solution for survival and regrowth was PVS3, which induced a high survival rate after 60 minutes of incubation. For a high efficiency, the best pre-treatment condition for vitrification was incubation in 88 mM sucrose for 24 h, 0.3M sucrose for 16 h, 0.5 M sucrose for 6 h, and 0.7 M sucrose for 3 h, in a descending order. The ploidy levels were the same in the mother plants and following cryopreservation, which confirmed the absence of any gene mutation.

• Korean Journal of Plant Resources
• /
• v.29 no.3
• /
• pp.331-338
• /
• 2016

The present study aimed to compare and investigate the morphological characteristics and yield components according to ploidy level of diploid and tetraploid Platycodon grandiflorum under vinyl-greenhouse and open field conditions. Plant height of diploid and tetraploid P. grandiflorum was 51.3 ㎝, 54.0 ㎝, respectively. The results revealed that the plants grown in the vinyl-greenhouse showed significantly higher growth compared to those grown in the open field. Regardless of the growing place, diploid and tetraploid of P. grandiflorum showed the rapid elongation of internodes after 4 and 3 internodes respectively and elongation tends to be decreased as entering the flower-bud differentiation period. The starting day of flowering in vinyl-greenhouse cultivation was found to be faster than that of the open field cultivation by 2∼3 days and tended to be delayed by about 5∼6 days in tetraploid P. grandiflorum compared to diploid. Fresh weight of roots from the vinyl-greenhouse cultivation showed a high quantity as 34.2g and 49.4g in diploid and tetraploid P. grandiflorum, respectively and especially tetraploid P. grandiflorum was found to be increased by approximately 44.4% compared to other plots.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.7 no.3
• /
• pp.135-139
• /
• 1987

The influence of ploidy level on agronomic characteristics in italian ryegrass, Lolium multiflorum Lam, italicum, was studied using diploids (2x) and tetraploids (4x) on the upland of Livestock Experiment Station, Suweon. The results are summarized as follow: 1. Tetraploid cultivars are in general dark green in leaf color and strong glittered. 2. Diploid cultivars are more resistant to cold than tetraploids but degree of resistance to cold depends on cultivars. The di-and tetraploids did not differ in summer survival and coldand heat resistance of di-Itetraploid cultivars were not related. 3. Tetraploid cultivars have larger leaf-blades, more rapid growth and higher leaf ratio to stem by heading than diploids. 4. Tetraploids possess significantly lower dry matter content than diploids. 5 . Fresh- and dry weight of tetraploids are similar with that of diploids but tetraploids are more leafy than diploids. 6. Seasonal yield depends more on the type of the cultivar than on its tetraploid nature.

• Horticultural Science & Technology
• /
• v.28 no.6
• /
• pp.996-1002
• /
• 2010

Flow cytometry (FCM) was used to measure the ploidy level of three different sports from 'Campbell Early' ($Vitis$ $labruscana$) grape. Results of the study showed different ploidy levels. FCM analysis for 'Campbell Early' grape which contains 2C DNA diploid cells showed single peak around 35-40 while 'Kyoho' grape with 4C DNA tetraploid cells had a different level of 70-80. However, analysis of the sports displayed a histogram with 2 peaks containing both 2C and 4C nuclei. There was no difference in histograms of 2C DNA flesh and pericarp; on the other hand, 4C DNA flesh type of sports had a different histogram from that of the 2C DNA pericarp. Chromosome numbers of diploid ('Campbell Early'), tetraploid ('Kyoho'), and three sports were counted under the microscope. 'Campbell Early' and 'Kyoho' have 38 and 76 chromosomes, respectively. Three different sports are mixoploids with mixtures of diploid and tetraploid cells. Microscopic observations of shoot apical meristems in sports from 'Campbell Early' grape were carried out to determine the type of plant chimera. 'Campbell Early' grape (diploid) and 'Kyoho' grape (tetraploid) showed that both had 2 tunica layers covering corpus cells, while the three different sports had tunica layers showing mostly oblique division. Most cells from 'Kyoho' grape were larger than 'Campbell Early' grape. Cells from L-2 and L-3 layers of the three sports were similar to 'Kyoho' grape in size, although all cells in L-1 surface layer were uniform in size like 'Campbell Early' grape. Results of FCM analysis indicated that both normal and polyploid cells could be intermixed in sports and could become mixoploidy consisting of diploid and tetraploid. All sports used in the tests were periclinal chimera plants with two distinct L-1 and L-2 cell layers. The result of this study suggests that all three sports which originated from 'Campbell Early' grape might be 2-4-4 type chimera formation.

• Asian Journal of Turfgrass Science
• /
• v.25 no.1
• /
• pp.17-21
• /
• 2011

Korean bennudagrass collections showed diverse genetic variations in their morphology, growth habit, and cytological aspects. Chromosome number and nuclear DNA content of the bennudagrasses indicated a ploidy level ranging from triploid (2n=3x) to hexaploid (2n=6x). In this study, we investigated the different responses of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, ascorbate peroxidase) and cell membrane stability of those bennudagrass cytotypes to lower temperature and shorter day length, which meets a dormant induction in Korea. All the antioxidant enzymes were found to be higher during dormant stage, while the heme-containing catalase which converts hydrogen peroxide ($H_2O_2$) to water and oxygen molecules was activated before dormant initiation in the three cytotypes except for hexaploid bennudagrass. The triploid and tetraploid which exhibited relatively finer leaves and a rapid establishment speed were found to show increased activities of superoxide dismutase and peroxidase enzyme. The malondialdehyde(MDA) which is a product of lipid peroxidation in the cell membrane damaged by the hydroxyl radical was increased in all cytotypes as temperature declined, and tri- and tetraploids which had more protective antioxidant enzymes demonstrated a significantly lower MDA production. Similarly electrolyte leakage was higher in penta- and hexaploidy, seemingly more damage to cell membrane when low temperature was implemented. Results indicated that antioxidant responses of different cytotypes were genetically specific, which needs to be investigated the relevance with the low temperature tolerance in the bermudagrass further at the molecular level.

• Journal of Plant Biotechnology
• /
• v.31 no.2
• /
• pp.103-108
• /
• 2004

This study was carried out to develop the efficient methods for the subsequent progeny of intersectional hybrid between Oriental and Asiatic lily hybrids. The pollen fertility and germination ability of 3 different allotetraploids (OAOA) after somatic chromosome doubling was ranged from 0 to 80 percent on artificial pollen germination medium. The number of BC$_1$ progeny using allotetraploid of F$_1$ OA-hybrid as male and female parent was different. The efficiency of BC$_1$ progeny production was increased when F$_1$OA-hybrids was used as male rather than as female parent. And in back crosses of F$_1$ OA-hybrids with the Asiatic and Oriental hybrids, Asiatic hybrids showed higher efficiency on BC$_1$ progeny production. The ploidy level between 2x or 4x Asiatic hybrid and allotetraploid F$_1$ OA-hybrid was determined and showed higher progeny production in 2x-4x crosses rather than 4x-4x.

• Journal of Aquaculture
• /
• v.6 no.1
• /
• pp.55-62
• /
• 1993

A tetraploid cyprinid loach, Misgurnus anguillicaudatus was induced by applying heat shock. The efficiency of inductions changed with the time of initiation of treatment and the duration of treatment. The highest incidence of tetraploid was obtained at the treatment of $41^{\circ}C$ for 3 min, 28 min after fertilization. Ploidy level was estimated by kariological examination and flow cytometric analysis. The tetraploid cyprinid loach had 4n = 100 chromosomes, while the diploid had 2n = 50. The erythrocytic volume of the tetraploid was 1.65 times larger than that of the diploid. The DNA content of the tetraploid and diploid showed 6.547 pg/cell and 3.067 pg/cell, respectively.

• Development and Reproduction
• /
• v.19 no.3
• /
• pp.127-134
• /
• 2015

The influence of triploidization on cell and nucleus size characteristics of the same tissues of erythrocyte, retina, kidney, hepatocyte and midgut epithelium in marine medaka, Oryzias dancena has been determined histologically. Induced triploid fish are produced by cold shock treatments. Likewise, the size of horizontal cell nucleus in inner nuclear layer of retina, ganglion cell nucleus in ganglion cell layer of retina, proximal tubule cell of kidney, hepatocytes and nuclear height of midgut epithelium all appear to be significantly larger than diploid (P<0.05). On the other hand, retina thickness is larger in diploid than induced triploid (P<0.05). Induced triploid shows low density of cell number. Results of this study suggest that same characteristics in the induced triploid exhibiting larger cells and nucleus sizes with fewer number of cells than the diploid can be useful criteria for the distinction between diploid and induced triploid, and also the ploidy level in marine medaka.