• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.91-97
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• 1970

It is one of the important subjects in fall crop production of potatoes in korea to find the proper direct planting method as a substitute for transplanting method by sprouting inducement at seed-bed. From this point the author has undertaken this experiments to examine the effects of several handling methods of seed tuber pieces at planting on sprouting of fall grown potatoes at Ansung Agricultural College from August to september in 1969. The results of experiments induced sprouting with Gibberellin treatment using the variety Irish Cobbler were as follows; 1. Sun light exposure treatment to cut surface of potato seed pieces resulted in rotting of seed pieces and delay of sprouting and bud growth. Exposure more than three hours induced severe rotting(more than fifty percent) of seed pieces (Table I). 2. When soil moisture are abundant and the duration of sun light. exposure is short, even direct planting method of treated seed pieces with Gibberellin resulted in good potato stands (Table 2). 3. The direct planting method, as the rotting of seed pieces are avoidable are applicable in fall crop production of potatoes us a substitute for transplanting method because the sprouting and bud growth are promoted more in case of direct planting than transplanting (Table 3). 4. When the humidity in the bottle was low no healing effects was found by holding the seed pieces in large closed bottle under the trees for three days before planting (Table 2). 5. If duration of sunlight exposure is short, no difference of potato stands between clear day planting and cloudy day plant ing (Table 3). 6. As long as soil moisture deficiency. was not induced the irrigation at planting shows no effects to protect the seed piece rotting after planting (Table 3).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.356-360
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• 2002

The seedlings of yacon (Polymnia sonchifolia Poeppig ＆ Endlicher), which were cuttings, plug seedling (PS), crown bud before sprouting (CBBS), crown bud after sprouting (CBAS), and divided seedling after budding (DSAB) were planted at 70$\times$50 cm planting distance on ridge; that was interow spacingintrarow spacing, and about 28,500$\pm$71 plants/ha. CBBS didn't need work and equipment to raise seedlings. PS and DSAB grew taller to 140.5 and 143.3cm, respectively, than others at 150 days after planting. In the changes of plant height, PS and DSAB showed taller than others during growth period, cuttings, CBBS, and CBAS grew rapidly in middle growth stage. Excepting main stem and petiole length, other characters were significant for seedling. Fresh weights were different among seedlings. Even though the yield of plants grown from CBAS and CBBS were lower with 34.7 and 36.4 ton/ha, respectively, than 3.6 ton/ha of DSAB; its yield index were over 95%, hence, those of plants grown from cutting and PS were lower with 73 and 87%, respectively. The ratio of tuberous roots over 200g to total tuberous roots per plant was the highest from DSAB. Most of tuberous roots were under 200g per tuberous root from cuttings. CBBS, CBAS, and DSAB are suitable to use seedlings for high yield of yacono. Yacon plant by DSAB much produced tuberous root of over 200g.

• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.1-8
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• 1986

This study was conducted to bring light on inducing factors for non-sprouting occured in the mulberry field of Kyungpook Province in 1983. The results are as follws ; 1. In spring, winter buds were suddenly died during germination, necrosis appeared in pholem and cortex of non-sprouting stem and measles at the bottom of non-sprouting stem. 2. The depth of available of soil was more shallow in the non-sproutiong field than in healthy field. 3. There was no signifioant difference between the healthy field and non-sprouting field in siol PH, the content of organic matter, available phosphorous and exchangeble cations. 4. Available boron content in soil was significantly more in healthy field than in non-sprouting field. 5. Boron content in leaf and bark was significantly lower in the non-sproutiong tree than in the healthy tree. 6. The non-sprouting fields were completely controlled by the application of 6kg/10a borax. 7. Cold tolerance of the mulberry tree was higher in the mulberry tree with boron than in the mulberry tree without boron. 8. Mulberry tree in Kyungpook Province in 1983 may absorb water earlier compared with the average year because of high temperature at the end of March, 1983 and they had been damaged by frost injuary due to the lowest temperature (-6.4$^{\circ}C$) on the grass at the beginning of April 1983. As the above results, non-sprouting bud in the mulberry fields of Kyungpook Province in 1983 had been occured by low temperature and boron deficiency and boron deficiency of mulberry trees accelerared the frost injury.

• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.379-384
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• 2015

Background : Considerable time and effort is required to develop new Panax ginseng varieties. Ginseng breeders have been developing techniques to shorten the breeding cycle to resolve this problem. In this study, we investigated the effects of adding $GA_3$ and alternating temperature (AT, $2^{\circ}C{\rightarrow}-2^{\circ}C{\rightarrow}2^{\circ}C$) on breaking bud dormancy in the varieties (Chungsun and Sunun) of ginseng root. Methods and Results : The $GA_3$ soaking treatment and AT were applied to one year old roots, which greatly accelerated the emergence of new buds. In one year old roots, new buds emerged from the 4th day post transplanting and after breaking dormancy with $GA_3$ and AT treatments. The emergence of new buds was completed within two weeks. The rate of bud emergence for Chungsun was 60% - 98% over 15 - 60 days after the AT and $GA_3$ treatments. The emergence rate of Sunun was 46% - 92%. Normal growth of the ginseng seedling was observed in spite of the early breaking of bud dormancy by combined $GA_3$ and AT treatments. Conclusions : $GA_3$ and AT treatments shortened the dormancy period and facilitated the stable emergence of ginseng seedlings. However, some plants suffered deformities and early sprouting owing to the combined $GA_3$ and AT treatments. Early sprouting was free from dormancy after leaf fall from the of aerial part of the plant.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.409-414
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• 2016

Background: The low survival rate of in vitro regenerated Panax ginseng plantlets after transfer to soil is the main obstacle for their successful micropropagation and molecular breeding. In most cases, young plantlets converted from somatic embryos are transferred to soil. Methods: In vitro thickened taproots, which were produced after prolonged culture of ginseng plantlets, were transferred to soil. Results: Taproot thickening of plantlets occurred near hypocotyl and primary roots. Elevated concentration of sucrose in the medium stimulated the root thickening of plantlets. Senescence of shoots occurred following the prolonged culture of plantlets. Once the leaves of plantlets senesced, the buds on taproots developed a dormant tendency. Gibberellic acid treatment was required for dormancy breaking of the buds. Analysis of endogenous abscisic acid revealed that the content of abscisic acid in taproots with senescent shoots was comparatively higher than that of taproots with green shoots. Thickened taproots were transferred to soil, followed by exposure to gibberellic acid or a cold temperature of $2^{\circ}C$ for 4 mo. Cold treatment of roots at $2^{\circ}C$ for 4 mo resulted in bud sprouting in 84% of roots. Spraying of 100 mg/L gibberellic acid also induced the bud sprouting in 81% roots. Conclusion: Soil transfer of dormant taproots of P. ginseng has advantages since they do not require an acclimatization procedure, humidity control of plants, and photoautotrophic growth, and a high soil survival rate was attained.

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.1-7
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• 1992

The experiment was conducted to investigate effects of bensulfuron-methyl{methyl 2-((((((4,6-dimethoxypyrimidin-2-yl)amino)carbony)amino)sulfonyl)methyl)benzoate}on bud sprouting, percent regrowth, and regrowth from growth cessation in Eleocharis kuroguwai. Application of bensulfuron-methyl resulted in sprouts of two of three lateral buds in addition to the apical bud of E. kuroguwai. With bensulfuron-methyl the culms elongated from the sprouted buds were killed soon after emergence. However, the buds remained biologically active. During the period of growth cessation the tuber buds respired in a minimum rate, but respiration began to increase with regrowth. At regrowth increase in the respiration was greater in the lateral buds than in the apical bud. Days required to regrowth was 35 days in the suppressed apical bud when applied at the rate of 51 g a. i. ha bensulfuron-methyl, while the suppressed lateral buds sprouted first and second required 29 and 28 dyas, respectively. After regrowth number of new culms was two to three times greater in the lateral buds than in the apical bud.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.1
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• pp.51-58
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• 2014

Freezing hardiness of winter bud and branch of several pear (Pyrus pyrifolia) cultivars according to degree and duration of low temperatures was investigated by sprouting, electrolyte leaching rate and triphenyltetrazolium chloride (TTC). Sprouting rate as infected by degree and duration of low temperature were different between cultivars. The lower temperature, the longer duration, sprouting rate was decreased. Electrolyte leaching rate was showed above 30% at below $-30^{\circ}C$ treatment regardless of cultivars and duration. The lower temperature and the longer duration, Electrolyte leaching rate was increased. Electrolyte leaching rates of Manpungbae, Niitaka and Chuwhangbae at $-30^{\circ}C$ for 9 hours treatment which were observed high sprouting rate, were lower than those of other varieties. Absorbance rates by TTC test at $-21^{\circ}C$ treatment were 66.0 to 96.5% for 6 hours, 49.4 to 91.9% for 9 hours, and 37.3 to 89.4% for 12 hours. Freezing hardiness of pear cultivars at ecodormancy was different according to degree and duration of low temperature treatments.

• Journal of Sericultural and Entomological Science
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• v.30 no.2
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• pp.75-83
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• 1988

These experiments were carried out to define the rest period of mulberry by treating growth regulators in Taegu, Korea. Results obtained were as follows: It was recognized that the depth of rest in Taegu, Korea, was not deeper than that in Tokyo and Kagoshima, Japan. The rest of mulberry was begun at the end of September, subsequently became deeper through the first October into the late October and then turned gradually into quiescence by the beginning of November. Buds sprayed by gibberellic acid ($GA_3$) 10ppm and urea 0.5% were promoted to sprout, while naphthalene acetic acid (NAA) 0.02% inhibited strongly bud sprouting and abscisic acid (ABA) 20ppm had no effect on the rest of mulberry. Gibberellic acid 10ppm enhanced the rate of green color of bud after incubation for 10 days at $30^{\circ}C$. By the portion of mulberry stems, the depth of rest was different that the middle buds were less dormant than those lower. The optimal time required for the mulberry winter bud break is 15 days incubation at $30^{\circ}C$ as treated with $GA_3$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.7-13
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• 1989

The present study was carried out to get the basic information for clarifying physiological mechanism of breaking dormancy and sprouting in Panax ginseng roots. Changes in Abscisic acid (ABA) content and Gibberellin (GA) activity were investigated in one-year-old root during stratification at 4$^{\circ}C$. 15$^{\circ}C$. and 15$^{\circ}C$ after 60day-treatment at 4$^{\circ}C$. Sprouting rate at 15$^{\circ}C$ was 35％ in 30days storage at 4$^{\circ}C$ and 100％ in longer than 60days, but there was no sprout in both the constant treatment at 4$^{\circ}C$ or 15$^{\circ}C$ regardless of the treatment period. The longer the period of low temperature treatment. number of days to the first and 50％ sprouting was shortened, and number of days to 50％ from first sprouting was also shortened. ABA content in the upper part of root(contained bud) was gradually increased at both 4$^{\circ}C$ and 15$^{\circ}C$ as the treatment period was extended. and the degree of increase was higher at 15$^{\circ}C$. In the lower part. it showed a slight increase at 15$^{\circ}C$. while showed little change at 4$^{\circ}C$ throughout the treatment period. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$, it was greatly increased in the upper part. while rather slightly decreased in the lower part of root. GA activity in the upper part was gradually decreased at both 4$^{\circ}C$ and 15$^{\circ}C$, and the degree of decrease was higher at 15$^{\circ}C$. In the lower part. it was similar tendency to those in the upper part. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$. it was remarkably increased in both the upper and lower part. The increase was great in the low Rf region, while the decrease appeared relatively in the high Rf region compared to those of 60day-treatment at 4$^{\circ}C$. The above results indicated that the breaking dormancy and sprouting of bud were closely associated with the degree of GA activities in response to temperature condition .during stratification rather than the direct effect associated with the changes in ABA content.

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.1-4
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• 1977

This work was carried out to know the relation between the yield and the cutting length of mulberry branches in autumn. The results obtained are summarized as fellows, 1. Most of the experimented mulberry trees grew evenly, of which branches showed 171cm to 177cm in average length. 2. No difference could be seen in autumn yield among the treatments, however, the shorter branches were remained, the higher in ratio of re-sprouting bud. 3. The spring yield of cutting mode in 100cm and 200cm remained was as much as non-treatment, but dropped remarkably in below 80cm remained. The high productivity in the 100cm or above renamed mode accounts for the low ratio of no-sprouting bud and accelerating the growth of the shoot, which consequently become much of shoot yield per 1m of branch. By cutting branches, however, the ratio of amount of leaves per shoot became low. 4. The cutting mode in 100cm and 120cm remained can yield as much as non-treatment even in the total yields of spring and autumn. but 100cm mode seems to be more advanceable in autumn owing to a little sparing labor for picking leaves. Thus, the most desirable cutting mode in autumn may be in 100cm remained, which usually has been done at the part of one third or half of the whole branches.