• Horticultural Science & Technology
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• v.32 no.1
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• pp.1-9
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• 2014

This study investigated the effects of temperature on the shoot growth and flowering of potted kumquat [Fortunella margarita ( Lour.) Swingle] trees grown in subtropical conditions of I-Lan County in Taiwan. Temperature treatments included T 25-32, T 17-25, T 22, and T 18. The T 25-32 treatment trees were to the day/night temperatures of $25/18^{\circ}C$ for 2 weeks, followed by 28 weeks at $32/25^{\circ}C$. T 17-25 was exposed for 4 weeks to $17/10^{\circ}C$ followed by 26 weeks at $25/18^{\circ}C$. T 22 and T 18 were exposed at $22/18^{\circ}C$ and $18/13^{\circ}C$, respectively, for the entire duration of the experiment. Control trees were placed in a plastic greenhouse under conditions similar to the natural environment. The kumquat trees exposed to high-temperature environment of $32/25^{\circ}C$ showed more frequent and speedy sprouting of new buds, but induced the earlier termination of shoot elongation growth, resulting in decreased vegetative growth. The temperature treatments lower than $22^{\circ}C$ suppressed the new shoot production but increased the shoot growth period, resulting in increased shoot length and diameter. Temperatures higher than $25/18^{\circ}C$ readily induced flowering, with flowering being advanced under the higher temperature conditions such as $32/25^{\circ}C$. However, flowering was substantially inhibited under temperature conditions lower than $22/18^{\circ}C$, indicating the negative role of relatively lower temperatures on flowering of kumquat trees.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.23-23
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• 2021

Apple (Malus×domestica Borkh.; Rosaceae) is an important fruit crop grown mainly in temperate regions of the world. Tissue culture in vitro is a biotechnological technique that has been used to genetically improve cultivars (scions) and rootstocks. This could be important in the production of genetically uniform scions and rootstocks for commercial apple production. In nurseries, apple plants are produced by grafting scions onto rootstocks. The Cornell-Geneva (Geneva® series) breeding program has bred several dwarf rootstocks that are resistant to diseases and pests and are also cold hardy. This study was conducted to determine the optimal medium strength to improve sprouting shoot rate of apical meristem of the apple rootstocks of fire blight resistance. The apple rootstocks apical meristem at size (0.2 mm to 0.3 mm) with axillary buds were cultured on the MS(Murashige & Skoog) medium supplemented with plant growth regulators. The sprouting ratio and growth characteristics was evaluated after eight weeks in vitro culture. The highest rate of bud differentiation and shoot formation were 23.8% and 55.6%, respectively. After 6 weeks, shoots were regenerated from apical meristem, and their growth characteristics was significantly varied on the respective basal medium with different plant growth regulators. Our studies showed that the apple rootstocks the apple rootstocks of fire blight resistance plantlets could be successfully produced from apical meristem differentiated out of young twigs via organogenic regeneration.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.269-273
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• 2007

Freezing hardiness of winter bud and branch according to dormancy level and low temperature, in persimmon (Diospyros kaki) cultivars, was investigated by electrolyte leaching rate, triphenyltetrazolium chloride (TTC) test, and sprouting. Electrolyte leaching rate was lowest in branch of 20th January and was highest in the 20th March. The electrolyte leaching rate of 'Fuyu' and 'Cheongdobansi' was high in the 20th January and was low in the 20th February, but 'Uenishiwase' and 'Nishimurawase' was opposed to that. 'Hachiva' was the middle level in the cultivars. Absence rate by TTC test was highest in the 20th January and was low in the others. The 20th March had a great decrease in $-10^{\circ}C$ treatment. The absence rate of 'Fuyu' and 'Uenishiwase' was low in the 20th January and March and was high in the 20th February. 'Nishimurawase' and 'Hachiya' had a high level irrespective of dormancy level. Sprouting was highest in the 20th February and was lowest in 20th March. Most cultivars were not sprout in $-20^{\circ}C$ treatment and 'Fuyu', 'Nishimurawase' and 'Cheongdobansi' was a little high level irrespective of dormancy level. 'Hachiya' was only high in the 20th January. Thus, freezing hardiness of persimmon was very weak low temperature after dormancy breaking and was not different between astringent and non-astringent persimmon.

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.189-197
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• 1989

This study was carried out to produce the grafts of Juglans sinensis by juvenile grafting method which epicotyl of newly germinated seeds were used as stocks and juvenile fresh shoots were used as scion. The results obtained were as follows ; 1. When plastic tube installed covering up seed with soil up to 6cm height for diameter increment of epicotyl, the epicotyl can be grown up to thickness of 10mm. 2. When the soft fruit branches and the soft water sprout with the terminal bud 8cm to 12cm long were used as scions, the survival rates showed 90 Percent. 3. The optimum date for making juvenile grafts was around the 20th of May, and the survival rates of grafted seedlings showed 86 percent in average. 4. The grafted seedlings showed first sprouting the 15th of June, that is 25 days after making graft, and the sprouting rate was 72 percent. 5. The height-growth of grafted seedlings finished at the end of July, and diameter growth lasted into the end of October. 6. There was positive correlation between the height of grafted seedlings and the diameter at root collar. 7. In general, it takes two years to make plantable graft seedlings from hardwood scion and stock, but the juvenile graft seedlings can be easily obtained in a year and so it seems to be economic.

• Horticultural Science & Technology
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• v.32 no.3
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• pp.296-302
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• 2014

The foliage of variegated Solomon's seal is excellent in cut flower arrangements. However, it has a restricted marketing period because the harvesting is limited in spring and summer. The increased interest requires the year-round production, thus techniques for dormancy breaking and forcing without low temperature treatment is needed. Therefore, experiments were conducted to d etermine whether gibberellic acid (GA) could break dormancy in variegated Solomon's seal. Thes prouting of dormant bud did not occur throughout the experiment when $GA_3$ $400mg{\cdot}L^{-1}$ was applied to dormant rhizomes as a soil drench. However, when plants were treated with a GA drench after scratch with razor blade or were given direct injection of GA, percent sprouting was increased up to 100 or 83.3%, respectively. However, because treatments with razor or syringe may damage internal organs, we tested another method, scarifying the rhizomes with sodium hypochlorite (NaOCl). Rhizome scarification with 4% NaOCl for 6 or 24 hours followed by drench of $GA_3$ $400mg{\cdot}L^{-1}$ increased the dormancy breaking percentage to 70 or 86.7%, respectively. Moreover, scarified and GA-treated rhizomes produced more leaves than untreated or GA-soil drenched plants in the glasshouse. These results showed the possibility of year-round production of variegated Solomon's seal foliage with rhizome scarification and GA treatments.

• Korean journal of applied entomology
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• v.4
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• pp.7-10
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• 1965

In an experiment to evaluate the various aspects of symptom of witches' broom of jujube tree with two different kinds of scions, taken from diseased plant and stem- grafted upon sound stocks-one cut before wintering(stored in cellar), the other after wintering, it was observed that the disease rate of those cut before wintering(Nov.) was $\98\%$ whereas those cut after wintering(March) showed much lower rate, $3\%$ initially and gradually increased up to $39\%$. In another experiment of diseased bud grafted into healthy seedling, the finding made in the following year was that 14 stocks(only one of which salt union by callusing) were infected out of the given 23- in the initial stage only 4, yet gradually increased to the number of 14. The shoots from the ground portion of the diseased stock were in general more quickly subjected to the disease than the others. Under natural condition, the diseased trees develop at first seemingly the same leaves as healthy ones; it is not until the branches and loaves grow to a considerable degree that the symptom appears. Once appearing, tile disease grows and the symptom continues to appear as late as in Sept. and early Oct., causing tile plant to develop the extraordinary branches and leaves of extremely reduced size, the typical symptom of witches' broom. Such phenomenon can be observed in the experiments of the foregoing paragraphs. And the suckers and roots of diseased plant are bound to be infected, it was found out with no exception. Viewing from the results of the above experiments and observation, it is believed that the low temperature during winter causes the virus in the above-ground portion of diseased plant to diminish or inactivated, and subsequently the virus in the roots moves up or multiply in the sprouting season.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10a
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• pp.114-115
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• 2000

Aralia elata is found in mountain areas all over Korean peninsula. Aralia elata is the scientific name for Japanese angelica tree. The tree belongs to the family Araliaceae, commonly known as ginseng family. Bud sprouts from apical shoot tip of the plants are rich in flavor and thus mainly used for both folk medicine and vegetable. The stalks with apical buds are gathered in the early spring and planted in sandy soil or water in the greenhouse. The sprouting buds are then collected and sold as fresh vegetable. Although the plants have been used for food, they have been cultivated in a very small scale. In spring, local farmers just go around mountain areas to search the trees and gather the stalks as much as they get and sell them to the market. No conservation efforts have been made to stop the exploitation or to save the dwindling population. We tried to provide local farmers with the plants that may be used as an alternative to stalks from wild populations. This will bel! p conserve the wild populations. However, it is hard to propagate them either by conventional cuttings or by seed germination in a short period of time. Mass propagation using tissue culture systems have shown a great promise with several woody plants. Recently we developed a mass propagation technique via somatic embryogenesis system using mature and/or juvenile explants for Aralia elata. Several factors affecting somatic embryogenesis system including SE(somatic embryo) induction, embryogenic callus proliferation, SE germination, plant regeneration and transplanting to field frill be presented. And some problems arising for the somatic embryogenesis system will be also discussed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.16-17
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• 2000

Aralia elata is found in mountain areas all over Korean peninsula. Aralia elata is the scientific name for Japanese angelica tree. The tree belongs to the family Araliaceae, commonly known as ginseng family. Bud sprouts from apical shoot tip of the plants are rich in flavor and thus mainly used for both folk medicine and vegetable. The stalks with apical buds are gathered in the early spring and planted in sandy soil or water in the greenhouse. The sprouting buds are then collected and sold as fresh vegetable. Although the plants have been used for food, they have been cultivated in a very small scale. In spring, local farmers just go around mountain areas to search the trees and gather the stalks as much as they get and sell them to the market. No conservation efforts have been made to stop the exploitation or to save the dwindling population. We tried to provide local farmers with the plants that may be used as an alternative to stalks from wild populations. This will hel! p conserve the wild populations. However, it is hard to propagate them either by conventional cuttings or by seed germination in a short period of time. Mass propagation using tissue culture systems have shown a great promise with several woody plants. Recently we developed a mass propagation technique via somatic embryogenesis system using mature and/ or juvenile explants for Aralia elata. Several factors affecting somatic embryogenesis system including SE(somatic embryo) induction, embryogenic callus proliferation, SE germination, plant regeneration and transplanting to field will be presented. And some problems arising for the somatic embryogenesis system will be also discussed.lso discussed.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.329-332
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• 1999

The objective of this study was to determine the influence of grafting timing, rootstock cut timing and leaf removal with promalin ($GA_{4+7}+BA$) treatments on the maiden tree growth, lateral development and flower bud initiation. In mid-March 1997, two-year-old M.9-T337 rootstocks selected with trunk diameter over 1 cm were planted in the field. Chip budding with 'Fuji' scion on M.9-T337 rootstock budded in mid-April was earlier in sprouting than chip budding in mid-June. Late cutting chip budding (LCCB) with 'Fuji' scion on M.9-T337 rootstock was lower in the failed budding percentage with 14% than that of early cutting chip budding (ECCB). Especially, ECCB in April was not suitable for scion growth such as uniformity with high percentage of failed tree. Grafting timing in mid-June and rootstock cutting timing of LCCB induced more branches and flower buds than other treatments. Removal of 8 to 10 uppermost immature leaves on central leader stem and application of Promalin 250 mg/L after every 30 cm of terminal growth produced a 189 cm tall tree with 9 flower buds and 14.2 short lateral shoot from 30 to 35 cm long in length in 1998. Promalin increased branching on second-season growth and, when combined with leaf removal, resulted in uniform distribution of branches along the central leader stem.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.221-225
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• 2008

Lilium formolongi 'Fl August' plantlets with scale-leaves and scale-bulb were treated at 10, 15, 20, $25^{\circ}C$ for 15, 30, or 45 days and planted in February, March, April and May. In the April planting, flowering percentage was below 10% and in the May planting no flowering occurred. Sprouting and flowering percentages were lower at the late planting times. Days to flowering of the April planting was 110.8 days compared to 128 days for the February planting. Plant height and numbers of leaves were reduced to 7.2 in May planting, compared to 40.5 leaves in February planting, and almost no flowers emerged in either the April or May plantings. Plantlets exposed to 10 or $15^{\circ}C$ flowered at 80 percent or higher at all treatment durations, but at 20 or $25^{\circ}C$ flowering percentages were lower, with 30% or less in the $25^{\circ}C$ treatment. In the $15^{\circ}C$ treatment days to flowering were less than 100 days, while the number of flowers and flower bud differentiation were greatest in the $15^{\circ}C$ treatment. Cytokinin and auxin were analyzed in bulblets grown at 15, 20 and $25^{\circ}C$. T-zeatin content was three times greater in the $15^{\circ}C$ treatment than at $25^{\circ}C$, but the content of indoleacetic acid (IAA) was less at $15^{\circ}C$ than at 20 and $25^{\circ}C$. In the $15^{\circ}C$ treatment, T-zeatin content was about twice the IAA content in the scale- bulblet. The auxin and cytokinin balance may affect flower bud differentiation. $15^{\circ}C$ with 30 days was most effective for flowering in scale-bulblet and planting of February and March were effective for flowering too.