• Korean Journal of Plant Resources
• /
• v.22 no.3
• /
• pp.209-214
• /
• 2009

To facilitate the introgression of F. esculentum into the traits of F. homotropicum, several accessions of the hybrids between these two species were pollinated with F. esculentum as the recurrent parent. The embryo in vitro rescue was performed to increase the recovery of backcross progenies. The $F_{2}$ generation was more amenable than $F_{1}$ hybrids to produce backcross progenies. The $F_{1}$ hybrids were backcrossed twice with common buckwheat (pin-type F. esculentum) (recurrent backcrossing). Also, alternate backcrosses with common buckwheat and F. homotropicum (congruity backcrossing) were carried out. Pollen tube growth of BC$F_{1}$ ${\times}$ F. esculentum (thrum) and F. homotropicum ${\times}$ BC$F_{1}$ was the disturbed penetration exceeded for all initial interspecific hybrids, and its requirement was proportionally lower when the common buckwheat was used as the recurrent parent and as the last parent of congruity hybrids. Effects of both common buckwheat and F. homotropicum on seed success rate for hybridization were observed. Growth of hybrid embryos before rescue, regeneration of mature hybrids all increased recurrent and congruity backcrosses and inter-crosses between $F_{1}$ plants and selected fertile plants of the second congruity backcrosses.

• Korean Journal of Agricultural Science
• /
• v.37 no.2
• /
• pp.199-207
• /
• 2010

This research was conducted to determine the influence of physiological and chemical properties of root substrates on the growth of the daughter plants of 'Maehyang' strawberry produced by bag culture. The daughter plants produced by stock plants during bag culture were individually separated and grown in 10-cm diameter plastic pots containing six different formulations of root substrates: a) 50% peatmoss plus 50% vermiculite (5:5 by volume, A), b) 70% peatmoss plus 30% perlite (7:3, B), c) 70% coir dust plus 30% perlite (7:3, C), d) mixture of 35% coir dust, 35% peatmoss, and 30% perlite (3.5:3.5:3.0, D), e) mixture of 20% rice hull, 70% coir dust, and 10% perlite (2:7:1, E), and f) 30% rice hull plus 70% coir dust (30:70, F). The container capacity and air filled porosity of the growing medium varied greatly among the six substrate formulations evaluated. The substrates E and F had less container capacity and higher air-holding spaces than the rest of the formulations. Therefore, these two formulations (E and F) may cause a problem in water management during the production of healthy daughter plants. The substrate formulations A, B, and D retained higher nitrogen (N) concentrations than other formulations containing coir dust or rice hull. The substrate formulations E and F which contained rice hull had lower N, phosphorus (P), and potassium(K) concentrations than other substrate formulations containing coir. The quality of the daughter plants grown in all six different substrate formulations was good with the crown diameters at around 10 mm. Fresh weights of the daughter plants grown in substrate formulations A, C, and D were higher than those obtained from B, E, and F. Dry weights of the daughter plants showed a similar trend. The daughter plants having high fresh and dry weights and increased crown diameter are in demand by the industry. For this reason, the substrate formulations A, C and D can readily be used as potting mixes during the production of 'Maehyang' strawberry transplants utilizing the bag culture system.

• Journal of the Korean Society of Tobacco Science
• /
• v.13 no.2
• /
• pp.48-51
• /
• 1991

A program was initiated to transfer potato virus Y vein-necrosis strain resistance from N. africana to N. tabacum The Fl plants between the above species were self-sterile, but all amphidiploid plants from the Fl plants and backcrossed flowers, that is, the N. tabacum flowers crossed with amphidiploid were self-fertile. The parent, amphidiploid plants of Fl, F2 population of the amphidiploid and the backcrossed generation were screened for a resistance of potato virus Y vein-necrosis strain isolated in Korea. The Chi-square values for the F2 population of the amphidiploid and the backcrossed generation fitted 35: 1 and 5 : 1 ratios of resistant to susceptible for the potato virus Y vein-necrosis strain, respectively. Therefore, it was found that the resistance of N. tabacum for the potato virus Y vein-necrosis strain was controlled by a single dominant gene.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.35 no.2
• /
• pp.165-170
• /
• 1990

In order to determine the relationship between dwarf gene and GA$_3$ response, three dwarf cultivars, Fukei 71, Seolak, and Tanginbozu, which were known to have d 50, d 47 and d 35 gene, respectively, were used as parents in this study. Three parents and their F$_1$ and F$_2$ generations were grown. Tillers of each plant were devided into two parts at 15 days after transplanting and was transplanted. One part of them was sprayed with GA$_3$ 50 ppm at booting stage. The internode length were measured at ripening stage in terms of GA$_3$ response. The internode was significantly elongated in Seolak and Tanginbozu, but not in Fukei 71. All F$_1$ plants of the crosses were tall, and their internode and culm were significantly elongated with the spraying of GA$_3$. Dwarf plants which are not responded to GA$_3$ were selected in the F$_2$'s of Seolak/Fukei 71 and Fukei 71/Tanginbozu crosses, and backcrossed to Fukei 71. All of these BC$_1$F$_1$ plants were uniform in the culm length and not responded to GA$_3$ treatment. The dwarf gene, d 50 of Fukei 71 seems to be closely associated with the facter of non-response to GA$_3$.

• Journal of Life Science
• /
• v.21 no.12
• /
• pp.1659-1665
• /
• 2011

In Citrus, an $F_1$ segregation population of 150 plants was constructed from a cross between 'Kiyomi' (C. unshiu ${\times}$ C. sinensis) carrying the male sterility trait and 'Jinkyool' (C. sunki). Sequence-related amplification polymorphism (SRAP) combined with bulked segregant analysis was used to develop markers linked to male fertility. In the $F_1$ population, 66 out of 150 seedlings had aborted anthers and the ratio of male sterile plants to fertile plants in the progenies matched the expected Mendelian segregation ratio of 1:1 ($x^2$ =2.16 at p=0.05). From the profiling of the 197 SRAP primer sets, three SRAP primer sets (F4/R27, F39/R60, and F15/R37) that were closely linked to the target trait were identified and successfully converted into a sequence characterized amplified region (SCAR) marker for selection of male fertility in citrus. The SCAR marker, using the pMS 33U/pMS 1462L primer set specifically, produced a single 1.4-Kb fragment that was linked to male fertility. Our results suggested that this SCAR marker can be useful for marker-assisted selection of male sterile individuals in breeding $F_1$ progenies in Citrus.

• Journal of Plant Biology
• /
• v.6 no.1
• /
• pp.1-7
• /
• 1963

Two individuals of intergeneric hybrids in the crossing of Brassica pekinensis ♀$\times$Raphanus sativus ♂ were obtained, and among the three kinds of plants, Brassica, Raphanus, and F1, comparison on the mega- and microsporogenesis, megagammetophyte formation, and morphological changes in the developing sporangia, etc., were made. Differences between Brassica and Raphanus were observed in the shape of mega- and microsporangia, their changes in development, and the formation of megagametophyte. Sporangia of the F1 plants, until pre-meiotic stage, show intermediate, maternal, paternal, or vigorous inclination, and the difference of these characteristics when compared with those of the parent is slight. Meiotic irregularity resulted from the intergeneric hybridity of F1 plant gives rise to the abnormal mega- and microspore and accompanied abortive female and male gametophytes, bringing about the remarkable differences from its parent in the morphological changes of the developing mega- and microsporangia.

• Journal of Plant Biology
• /
• v.15 no.2
• /
• pp.7-19
• /
• 1972

The studies of density effect or the effect of population density on plant growth have been done on basis of dry matter production with Raphanus acanthiformis var. simoodaeguen, Brassica campestris var. Pekinensis f. namsounsokoombecheu, Oryza sativa f. kimmajae and O. sativa f. mangyeng grown in the various spacing. 1. In the early period of plant growth in dry weight was not different each other among varying densities, but as time advanced the plant grown vast space grew sufficiently compared with those of narrow one. 2. Iogarithmic relation between the growth of plant (W) and the density (P), log W-log P in the material plants, were approximated by two straight lines, one was horizontal line and another inclined: the former showed non-competition density and the latter competition density addition to these the point interlinking both lines were implied of the optimum density per unit land area at certain growth period. 3. The values of relatvie growth rate (RGR) and net assimilation rate (NAR) were decreased as increase in the density, while those of leaf area ratio (LAR) were rather increased in the same condition, with minor exception. From these results and relation between the productive structure and due to lack of the recieved light intensity owing to the mutal shading among the plants.

• Proceedings of the Ginseng society Conference
• /
• 2002.10a
• /
• pp.467-476
• /
• 2002

A large number of individual ginseng plants have been selected in the farmer's fields to develop new ginseng varieties with desirable traits since 1970s. Among them, Hwangsukjong with green stem and yellow berry was selected as a ginseng germplasm. The phenotype of Hwangsukjong is quite different from Jakyungjong that has violet stem and red berry and has been cultivated in most of ginseng fields. Therefore, Hwangsukjong was crossed with Jakyungjong to clarify the inheritance of stem color and then the characteristics of $F_1\;and\;F_2$ hybrids were investigated. $F_1$ hybrid plants were similar to Jakyungjong in most of aerial part characters and showed hybrid vigor in fresh weight of root and weight of 100 seeds. In $F_2$ generation, the stem color was segregated in a ratio of 3 violet to 1 green. From this result, it was elucidated that violet color was controlled by single dominant gene. In another experiment, DNA was extracted from parents (Jakyungjong and Hwangsukjong) and $F_1$ hybrid. For each primer evaluated, multiple band profile was produced comprising from one to five major bands plus a varying number of minor bands and amplified bands were detected among most primers. In case of UBC primer number 13, 17, 30, 31, and 43, band patterns of parents and $F_1$ hybrid were very similar, but the others were not. Especially, in {\sharp}1$, {\sharp}4$, and {\sharp}33$, specific band was produced in Hwangsukjong and $F_1$ hybrid while in {\sharp}6$, another specific band was produced in Jakyungjong and $F_1$ hybrid. Therefore, $F_1$ hybrid had all specific bands at these primers. So, these selective markers could be used for identification of characteristics of $F_2$ hybrids

• Horticultural Science & Technology
• /
• v.35 no.2
• /
• pp.276-286
• /
• 2017

Licorice, a traditional Korean medicinal plant, is recognized for its main active ingredient, glycyrrhizin. The level of glycyrrhizin in Chinese licorice (Glycyrrhiza uralensis) is lower than the reference level (2.5%) set by the Korean Pharmacopoeia, reducing its value as a medicinal herb. In this study, we aimed to overcome this problem by generating an interspecific licorice hybrid by crossing European licorice (G. glabra) with Chinese licorice, resulting in the production of 32 $F_1$ lines. A comparison of genetic traits revealed variations in glycyrrhizin content among lines, ranging from 1.5 to 5.6%, with a mean value of 3.2%; these values are higher than that of the parental plants. Additionally, 25 lines (78.1%) had a glycyrrhizin content greater than 2.5%, which is higher than the reference level set by the Korean Pharmacopoeia. Four of these lines had glycyrrhizin levels higher than the WHO recommended level of 4.0%. A comparison of phenotypic characteristics showed that the leaves of the hybrids possessed all of the characteristics of European and Chinese licorice; however, the stems of most hybrids had characteristics of European licorice. Finally, we determined the genetic distances of 34 samples of Glycyrrhiza plants (parents, 32 $F_1$ lines) by random amplified polymorphic DNA (RAPD); the $F_1$ lines showed a close genetic distance. We plan to develop to a cultivar using five of these lines (glycyrrhizin content < 4.0%).

• Journal of Microbiology and Biotechnology
• /
• v.30 no.5
• /
• pp.708-716
• /
• 2020

The purpose of this study was to identify strawberry wilt pathogens and evaluate the efficacy of Chlorella fusca CHK0059 for improving plant growth and suppressing Fusarium wilt. We identified 10 isolates of wilt pathogens of non-pesticide Seolhyang strawberry plant, including Fusarium oxysporum f. sp. fragariae, using morphological and molecular analysis. On the 15^th day after 0.4% CHK0059 treatment, the plant height of the untreated control strawberry plants was significantly greater than that of the CHK0059-treated strawberry plants. After 85 days, both treatments showed a similar tendency regarding the height of the strawberry plants. However, the thickness of strawberry leaves treated with the CHK0059 was found to be 1 mm thicker than that of the untreated control. The flowering percentage of the CHK0059 plants was also 40.2% higher on average than that of the untreated control. The chlorophyll content of strawberry leaves treated with the CHK0059 was also, on average, 6.63% higher than that of the untreated control. After 90 days of the CHK0059 treatment, the incidence of Fusarium wilt in the CHK0059-treated plants had reduced by 9.8% on average compared to the untreated control. The population density of F. oxysporum f. sp. fragariae was also reduced by approximately 86.8% in the CHK0059-treated plants by comparison to the untreated control at 70 days after treatment. The results indicate that the microalga C. fusca CHK0059 is an efficient biological agent for improving strawberry plant growth and suppressing Fusarium wilt disease in organic strawberries.