• Plant Biotechnology Reports
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• v.2 no.4
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• pp.227-231
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• 2008

D-class cyclins play important roles in controlling the cell cycle in development and in response to external signals by forming the regulatory subunit of cyclin-dependent kinase (CDK) complexes. To evaluate the effects of D-class cyclins in transgenic rice plants, Arabidopsis cyclin D2 gene (CycD2) was linked to the maize ubiquitin1 promoter (Ubi1) and introduced into rice by the Agrobacterium-mediated transformation method. Genomic deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and Western blot hybridizations of the Ubi1:-CycD2 plants revealed copy number of transgene and its increased expression in leaf and callus cells at messenger RNA (mRNA) and/or protein levels. The H1 kinase assay using the immunoprecipitates of protein extracts from the Ubi1:CycD2 plants and nontransgenic controls demonstrated that the introduced Arabidopsis CycD2 forms a functional CycD2/CDK complex with an unidentified CDK of rice. Shoot and root growth was enhanced in the Ubi1:CycD2 seedlings compared with nontransgenic controls, together, suggesting that Arabidopsis cyclin D2 interacts with a rice cyclin-dependent kinase, consequently enhancing seedling growth.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.47-51
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• 2010

Centipedegrass is a warm season turfgrass in the world. Chlorogenic acid (CA) is one of the important compounds present in the leaf of centipedegrass and already known as an antioxidant, CA has become a key resistance against insect pests and bacteria pathogens of agricultural and horticultural plants during seedling stage. Furthermore, CA is accumulated by abiotic stress such as an UV irradiation. In present study, we investigated enhancement of the level of CA upon gamma irradiation in centipedegrass. The high performance liquid chromatography (HPLC) data analysis showed an approximately increasing of the CA levels from among the irradiated samples. However, plants irradiated at 50 Gy showed a constant increase in the CA level (0.0066 to $0.114mg\;ml^{-1}$ and 0.0258 to $0.2211mg\;ml^{-1}$, respectively) from $3^{rd}$ to $15^{th}$ day among one and three month irradiated plants compared to control. The present study, indicates an increase in the CA level upon gamma irradiation, suggests strategy for conferment of strong resistance in seedling stage plants by gamma irradiation as simplicity and cheaply method.

• Journal of Ginseng Research
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• v.30 no.2
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• pp.78-81
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• 2006

Freshly harvested, immature (green) seeds of North American ginseng (Panax quinquefolius L.) were stratified for up to 3 years in plastic pails in controlled environment rooms at $5{\pm}1^{\circ}C$ for 9 months and then $21{\pm}2^{\circ}C$ for 3 months (Trt. 1, regular stratification), or continuously at $-2{\pm}0.2^{\circ}C$ (Trt. 2), or continuously at $3{\pm}0.2^{\circ}C$ (Trt. 3). During stratification at -2 and $3^{\circ}C$ embryos did not grow. On seeding in the field embryos grew rapidly and resultant seedlings were comparable to those from regularly stratified seed. Seedling emergence rate was acceptable at the industry expected rate of 68% after one year of storage, but not after two years storage when it declined to 17.5%. Seed rot was so severe in year 3 that no planting was carried out. Seedling and second year growth were similar at the three stratification temperatures; most importantly, root dry weight (economic yield) was similar. Low-temperature storage of freshly-harvested North American ginseng seed is an acceptable method for short-term retention of propagating material.

• Journal of Forest and Environmental Science
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• v.39 no.2
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• pp.96-104
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• 2023

The successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. Below-ground is hypothesized to have a major impact on seedling performance of species when planted in agriculture, and degraded areas with different types of mulching. This study investigated on Sg. Terla Forest Reserve in Cameron Highlands Pahang, Malaysia. In this study randomized complete block design (RCBD) was used. The excavation method was applied to study the root system development, above, and below ground biomass distributions under different types of mulching: coconut mulching (CM), oil palm mulching (OM), plastic mulching (PM) and control (CK). The root diameter, main root length, lateral root length, root coiling, and root direction toward to sun were recorded. The results in this study indicate that mulching had significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length, root: shoot ratio, dry biomass distributions, and above and below ground biomass did not showed significant effect among treatments. The highest values for root diameter, lateral root length, main root length, root distributions, dry biomass distributions and above and below ground biomass were showed in CM treatments. However 75% of root coiling was observed in seedlings between treatments.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.185-190
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• 1999

Autotoxic substance(s) from alfalfa(Medicago sativa L.) plants reduces germination and growth of adjacent new alfalfa after alfalfa. The autotoxic chemical(s) in alfalfa are clearly unknown. Our objective was to improve the sensitivity of an alfalfa seedling bioassay for evaluating autotoxic leaf extracts. We determined critical extract concentrations that inhibit seed germination and seedling growth, compared two different culture media, and evaluated the effects of extract sterilization on the sensitivity of the assay, by using streptomycin and autoclaving method. An agar medium in petri plate gave better responses of germination and seedling growth to the extracts than using filter paper in the plate. On agar medium, the concentration of extract required to reach 50% inhibition of root length was 2.7 g $kg^{-1}$, and of germination and hypocotyl length were 3.8 and 9.9 g $kg^{-1}$, respectively. Leaf extracts with 100 ppm streptomycin stimulated germination significantly compared to Leaf extract alone but reduced root length of control by 43%. Root length was more sensitive to the autotoxin(s) than was germination or hypocotyl length. These results suggest that agar medium mixed with extract and sterilization by autoclaving could be improved the consistency and precision of bioassay, and that root length was the best parameter of autotoxic effect of alfalfa leaf extract.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.297-305
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• 2008

A series of experiments were conducted to suggest efficient in vitro germination conditions to improve germination rate and aseptic seedling production in chicory and garland chrysanthemum. For this purpose, various levels of NaOCl concentration and soaking treatment time combinations were tasted. Fifteen minutes of soaking treatment with 5% NaOCl solution significantly improved germination and seedling formation percentages and prevented contamination in both chicory 'Precole' and 'Chiavari' and garland chrysanthemum 'Okiku 3'. There was no significant difference in germination response between MS and 1/2 MS medium compositions, but germination and seedling formation were delayed as sucrose concentration increased. Although petri-dish among various culture containers gave rise to improved germination responses in chicory 'Precole', there was no significant difference in germination responses among culture container types in chicory 'Chiavari' and garland chrysanthemum 'Okiku 3'. The ultrasonic treatment stimulated germination and seedling formation in both chicory cultivars but there was no effect in garland chrysanthemum 'Okiku 3'. The results suggested 15 minutes with 5% NaOCl for seed sterilization, 1/2 MS medium with no sucrose and petri-dish as proper medium composition and culture container, and 120 minutes with 5% NaOCl solution of ultrasonic treatment as promoting method for in vitro germination in chicory and garland chrysanthemum.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.56-62
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• 2005

This study was conducted to investigate the effect of grafting methods on plug seedling quality, growth after transplanting, and yield of oriental melon that those seedlings were raised in the 32 hole plug tray for protected cultivation. Number of leaf and leaf area in approach grafting were higher until 15 days after grafting but lower on 20 days after grafting. Plant height, stem diameter and content of chlorophyll were nearly the same of each grafting methods on 20 days after grafting. Growth of top part, that is, plant height, leaf number, and leaf area on root removed single cotyledon ordinary splice grafting was the highest among the grafting methods. In the underground part, dry weight of root was high and T/R ratio was the lowest. Seedling quality of root removed single cotyledon ordinary splice grafting was the highest among grafting methods before transplanting. Plant height, number of leaf, leaf area and dry weight of root removed single cotyledon ordinary splice grafting in the growth of field were the highest on 30 days after grafting among grafting methods and days required for first flowering was also shorter, 38.4 days among grafting methods. But Fruit weight, content of soluble solids, fruit hardness, and color characteristics in fruit quality were insignificant among each grafting methods. Consequently, grafting methods influenced on the seedling quality, of oriental melon early growth after transplanting and yields. It was concluded that root removed single cotyledon ordinary splice grafting was the best methods in present study. It will be needed to convert grafting methods. Thus new grafting method should be applied.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.365-370
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• 2014

This study was conducted to determine the effects of seed storage methods ($-20^{\circ}C$, stratification, $2^{\circ}C$ dry, $2^{\circ}C$ wet and room temperature) and $GA_3$ application (control, $dH_2O$, 10, 100, 1000 ppm) on seed germination and seedling growth of S. lyratum. As a result seed germination rate of S. lyratum was the highest at 91% when seeds were stored at room temperature and then soaked for 24 hours in $GA_3$ 10 ppm. And seedlings of S. lyratum showed the best quality when seed were stored at $2^{\circ}C$ dry and then soaked for 24 hours in $GA_3$ 1000 ppm, with the growth characteristics of plant height (47 mm), number of leaves (8), leaf width (12 mm), leaf length (19 mm), fresh weight (aerial/root part; 471/476 mg), dry weight (aerial/root; 106/41 mg) and seedling quality indices (106). Therefore, S. lyratum seed were stored at $2^{\circ}C$ dry, and then soaked for 24 hours in $GA_3$ 1000 ppm, seed germination rate was more than 80% and production of superior quality container seedlings.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.25-31
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• 2009

This study was conducted in order to breed Japonica salt tolerant rice and select salinity tolerant lines by establishing reliable and practical method of screening voluminous materials. Salinized nutrient solution by adding NaCl was effective compared with the salinized nutrient solution by adding 0.3%, 0.6% and 0.7% of diluted sea water. There was no different visual score of salinity injury between salinization using tap water and distilled water. Seedling salinity tolerant lines between region and order by year were showed very stable and reproducible results, 3~4.2 of visual score at Gyehwado-substation and International Rice Research Institute (IRRI, Philippines) in 2002, 2003 and 2004. Heading date of 6 selected seedling salt tolerant lines showed a range of 16. Aug.~21. Aug. and delayed 2~6 days than that of Donjinbyeo. Percentage of ripened grain and yield of milled rice in 6 lines was lower, 52.2~14.7% and 50~5%, respectively than those of Donjinbyeo.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.470-477
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• 2021

Amsonia ellipotica (Thumb.) Roem. & Schult. has less than 10 native places nationwide and is evaluated as an endangered species (EN) on the Korean Red List, so systematic breeding and cultivation methods are required. This study was carried out to establish an effective method for seedling production in A. elliopotica that can be developed as a genetic resource conservation and new ornamental material. This experiment was performed by varying the seedling production container (72, 105 and 128 cell trays), number of seeds sown in a cell (1, 2, and 4 per cell), soil type [horticultural soil and neutralized peat-moss: perlite mixed in 3:1, 4:1 (v:v)], additional fertilizer concentrations (0, 250, 500 and 1000 mg/L) and shading degrees (0, 55 and 75%). As a result of the study, growth increased with the increased in measuring capacity per cell of sowing container. According to number of seeding growth, sowing one seed per cell was the best. Seedling growth increased as the treatment concentrations increased, higher growth was in 1000 mg/L. On the other hand, during the shading treatment, growth significantly decreased regardless of shading degrees.