• Journal of Korean Society of Forest Science
• /
• v.97 no.1
• /
• pp.127-133
• /
• 2008

This study was conducted to establish the optimal condition for plant regeneration and acclimatization from somatic embryos of Panax ginseng. Cotyledon segments of Panax ginseng produced primary and secondary somatic embryos when cultured on MS and WPM media supplemented with 7% sucrose. To induce plantlet conversion, cotyledonary somatic embryos were cultured on WPM solid medium with $GA_3$ at various concentrations (1~30 mg/L) for 4 weeks. Plantlets were transferred to 1/2 WPM solid medium with $GA_3$ at various concentrations (0~5 mg/L) and 0.5% activated charcoal for shoot and root elongations. Elongated plantlets further developed into well-developed leaf and root system on 1/3 SH medium with 0.5% activated charcoal under ventilation condition for 5 months. The highest survival rate to soil was 75% when plantlets were regenerated on 1/3 SH medium without sucrose under ventilation condition.

• Journal of Bio-Environment Control
• /
• v.20 no.4
• /
• pp.341-345
• /
• 2011

This study was aimed to select the optimal mat condition using existing plant-mats for the efficient planting of bedding Chrysanthemum. At fifty days after cutting with Dendranthema grandiflorum 'Ford', root formation among the treatments using eight different mats outstood with the treatment using 10 mm thick coir net, which has medium inserted between mat layers - called C treatment, compared to other treatments; this treatment had the highest values in the plant height and shoot fresh weight, which were 29 cm and 5.6 g, respectively. On the contrary, in 40 days after transplanting root-formed mats to field, 12 mm thick jute net, which has medium inserted between mat layers, had the highest plants compared to other treatments. However, there was no significant difference in shoot weight compared to C treatment. In experiment of different lengths of cut, the results of growth after transplanting showed that 5 cm long cut performed best compared to 3 and 8 cm long cuts.

• Korean Journal of Environmental Agriculture
• /
• v.33 no.4
• /
• pp.372-380
• /
• 2014

BACKGROUND: This study was carried out in order to closely examine the influence of fertilization upon growth in container of seedling in indeciduous Quercus species (Q. mysinaefolia, Q. acuta and Q. glauca). METHODS AND RESULTS: Fertilizer level was made by adjusting water soluble compound fertilizer (N:P:K=19: 19:19, v/v) to 1000, 2000, $3000mg{\cdot}L^{-1}$ level along with non-fertilizing plot. Fertilization increased height, root collar diameter growth, and dry weight in these three species of trees. The more increase in fertilizer level led to the more rise even in growth of these species. H/D ratio and T/R ratio also showed tendency of getting bigger in the more rise in fertilizer level. Photosynthetic rate was shown to get higher in the higher fertilizer level according to fertilization in all the three species. In the analysis of root morphological traits, the total root length was surveyed to be longer in the more rise in fertilizer concentration. As even a case of root project area, surface area, and root volume is the similar tendency to characteristics in the total root length, a rise depending on fertilization was observed. CONCLUSION: In light of the results in this experiment, the fertilizer level is judged to be $2000mg{\cdot}L^{-1}$ level that is proper for production of 1-year-old container seedling in indeciduous Quercus species with excellent root development and high seedling quality index.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.61 no.1
• /
• pp.50-56
• /
• 2016

Direct seeding of sorghum (Sorghum bicolor L. Moench) has a problem of low yield including poor establishment. This poor establishment results from poor quality seed, poor seedbed preparation, seedling pests, poor sowing technique and high soil temperature. This study sought to establish the age at which sorghum seedlings can be transplanted with minimal effects on grain yield. Transplants were raised in 128 nursery tray pot. Five seedling ages were established by transplanting at 10 (T10), 15 (T15), 20 (T20), 25 (T25) and 30 (T30) days after planting (DAP). The treatment combinations were arranged in a randomized complete block design and replicated three times with an individual plot size of $6{\times}5m^2$. Each plot had five ridges with a planting space of $0.60{\times}0.20m^2$ at one plants per stand. Results showed that seedling age on transplanting significantly affected growths and yields to sorghum after transplanting. Plant heights and diameters of transplants at T15 were longer than the other transplants. Conclusively, The advantages of this practice were better control of crop density and greater yields; either to fill gaps after emerging and thinning of crops or to compensate for a growth period that was too short for a complete crop cycle.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.4
• /
• pp.475-481
• /
• 1996

This study was carried out to acquire the basic information of root growth under different pot size, imposing different space limitation on rhizosphere. Different size of pots that had same surface area but different depth, 5cm(Iength)$\times$5cm(width)$\times$30, 15, 5cm(depth), were used during the seedling stage of tobacco plant. Space limitation on rhizosphere affected not only the aerial growth, stem height, leaf area and shoot dry weight, but also root growth and root architecture. Aerial growth was highly related to growth of underground part, so space limitation on rhizosphere decreased aerial growth. Limitation on pot volume by reducing pot depth induced new rooting on crown. Root number and relative multiplication rate were higher in small pot that had 5cm depth than large pot, but total root length and mean extension rate showed reverse patterns. Root numbers of 1st order and 2nd order were increased as pot depth was increased, but the root number of 3rd order was increased in small pot. Root system of seedling grown in large pot distributed more horizontally than that in small pot at 20 days after temporary planting (DAT), but the root architecture of seedling was reversed at 25 DAT.

• Journal of Life Science
• /
• v.12 no.4
• /
• pp.416-422
• /
• 2002

Bacillus ehimensis YJ-37 was observed as a potential biological agent to control the occurrence of diseases and plant growth.promoting rhizobacteria (PGPR). Population density of B. ehimensis YJ-37 were higher 1.2~2 times in main roots and lateral roots than from nonrhizosphere soil and persisted around 10$^4$g root on the watermelon and radish root system upto 30 days after growing in pot condition. As a PGPR, B. ehimensis YJ-37 enhanced plant growth of watermelon and radish by soil treatment. The leaf area, hypocotyl length, root length and dry weight of radish were about 85, 33, 23 and 89% more than that of untreated plant, respectively. In case of watermelon were about 63, 27, 25 and 69% more than that of untreated plant, respectively. Biocontrol of damping-off in watermelon and radish caused by Rhizoctonia solani AG-4 and Pythium ultimum were carried out in pots using 3. ehimensis YJ-37. The results showed that might contribute to it's suppression of damping-off disease in field plants.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.28 no.2
• /
• pp.71-74
• /
• 2008

To investigate the sulfate utilization efficiency in different rape (Brassica napus) cultivars, sulfate uptake are analyzed under complete S-supply level (2.0mM ${SO_4}^{2-}$). This study used ten different genotypes of rape (Mokpo, Tamra, Youngsan, Naehan, Saturnin, Akela, Mosa, Capitol, Pollen and Colosse). For comparison of ${SO_4}^{2-}$ uptake among 10 cultivars, leaf number, leaf length and width, root length was also observed. Leaf length and width in all cultivars less variable among the cultivars examined. The longest root was shown in Saturnin (36.3 cm). ${SO_4}^{2-}$ uptake in Saturnin, Youngsan and Mokpo was significantly higher whereas that of Mosa and Pollen was relativety lower. Saturnin and Mokpo which have a high ${SO_4}^{2-}$ uptake exhibited a high ${NO_3}^-$ uptake.

• Korean Journal of Medicinal Crop Science
• /
• v.8 no.4
• /
• pp.297-303
• /
• 2000

A peony is perennial plant which comes under Paeoniaceae. The anatomical differences in root and stem of Paeonia lactiflora Pallas and Paeonia obovata Maxim. are studied. The length of the vessel members of P. lactiflora Pallas is a bit longer than that of P. obovata Maxim. in the stem and the roots, and the width of the vessel members of P. lactiflora Pallas is wider than that of P. obovata Maxim. in the stem and the root. The secondary xylem in the root of P. lactiflora Pallas is discontinuos scalariform arrangement while that of P. obovata Maxim. is continuous radical arrangement.

• Journal of Mushroom
• /
• v.17 no.1
• /
• pp.12-18
• /
• 2019

An auxin-producing bacterium Yangsong-1 was isolated from a button mushroom bed in Chung cheongnam-do. The strain Yangsong-1 was classified as a novel strain of Arthrobacter enclensis based on a chemotaxonomic and phylogenetic analysis. The isolated A. enclensis Yangsong-1 was confirmed to produce indole-3-acetic acid (IAA), which is one of the auxin hormones. When the concentration of IAA was assessed by HPLC quantity analysis, the maximum concentration of IAA, $152.903mg\;L^{-1}$, was detected from the culture broth incubated in R2A medium containing 0.2% L-tryptophan for 48 h at $35^{\circ}C$. A negative relationship between IAA production and pH was estimated to show that the increase in IAA caused pH acidification of the culture. The effect of the supplement on L-tryptophan, a known precursor of IAA production, appeared to be at maximal production at 0.2% concentration and was rather reduced at concentration above 0.4%. To investigate the growth-promoting effects on the crops, the culture broth of A. enclensis Yangsong-1 was placed in water cultures and seed pots of mung beans and lettuce. In consequence, the adventitious root induction and root growth of mung beans and lettuce were 1.5 and 1.9 times higher, respectively, than those of the control.

• Journal of Life Science
• /
• v.25 no.1
• /
• pp.37-43
• /
• 2015

We have investigated the effects of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) on the development of aerenchyma in the primary root of maize (Zea mays). Because plant hormones affected the longitudinal organization of the primary root, we need an indicator to direct the positions for comparison between control and hormone-treated roots. Therefore, the zones of the maize primary root were categorized as PR25, PR50 and PR75, where each value indicates the relative position between the root tip (PR0) and the base (PR100). Aerenchyma was not observed at PR25 and PR50 and rarely found at PR75 in the cortex of control roots. The aerenchymal area at PR75 increased in the presence of the ethylene precursor ACC or a natural auxin IAA. On the other hand, MeJA differentially acted on non-submerged and submerged roots. Exogenously applied MeJA suppressed the aerenchyma formation in non-submerged roots. When the primary root was submerged, aerenchymal area expanded prominently. The submergence-induced aerenchyma formation was amplified with MeJA. Lateral root primordia have been known to inhibit aerenchymal death of surrounding cells. All the three hormones stimulating aerenchyma formation as described above did not restore the inhibition caused by lateral root primordia, suggesting that the inhibitory step regulated by lateral root primordia can be located after hormonal signaling steps.