• Plant Resources
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• v.7 no.1
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• pp.29-35
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• 2004

Root chicory (Cichorium intybus L. var. sativus) is potential alternative medicinal and sugar crop which accumulates a high amount of linear polyfructan, inulin in its roots. A problem in root production is that over-wintered stock plants often flower. Once the plant becomes reproductive, stem elongation and root growth slows and floral buds arise from every node, rendering the plants useless for propagation. The objectives of this research was to examine the effectiveness of manipulating environmental factors containing photoperiod, temperature and number of leaf states. The experiment was performed in growth chamber to create two photoperiods (8 h, and 16 h) with three temperature regimes (5$^{\circ}C$/3$^{\circ}C$, 1$0^{\circ}C$/8$^{\circ}C$ and 15$^{\circ}C$/13$^{\circ}C$ day/night temperature) for a total of six treatments on three type of true-leaf stage of plant. Data of bolting rate, shoot and root length, shoot and fresh weight was invetigated in each treatments. This is the first report on changes in bolting rate and shoots and roots production during a whole growing season and differences in the effect of cold and photoperiod treatment depending on the true-leaf stage of plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.314-319
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• 1985

In order to observe the differences of several characters related to earliness, seven barley varieties were tested under two different photoperiodic conditions. Final leaf number per main stem under long day did not vary among varieties, but ranged 6 to 7 in early group and 9 to 10 in late group under shortday. Shoot apex of early varieties, Jogangbori and Oweolbori reached to X stage at 24 days, but that of late variety, CI 15446 did to X stag at 32 days after transplanting under short day. Spike length reached to maximum length at 39 days in early group, but at 51 days in late group. Saeolbori, CI 15446 and Hangmi were photo-sensitive, but Jogangbori and Oweolbori were photo-insensitive. Therefore, the photoperiodic response to short day was most responsible to heading time. Those results showed that early heading varieties had the characteristics with less variation of final leaves, less retardation of shoot apex development and spike elongation, and shorter period to flag leaf emergence under short day.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.221-221
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• 2022

Chromosome breakage occurred by DNA methylation inhibitor. Zebularine is known as DNA methylation inhibitor and suitable for water solubility among different DNA methylation inhibitors as 5-Azacytidine and 5-aza-2'-deoxycytidine. We used zebularine as mutagen according to different methods by roots absorption and seed imbibition. After zebularine treatment, DNA methylation inhibitor, we observed mitotic chromosome behavior what is different according to two different treatment methods. First, seed imbibition treatment in 1,000 μM of zebularine solution for 72 hours in dark conditions. The second treatment to seedlings of Keumkang was also treated in 1,000 μM of zebularine solution for 72 hours after germination. Root and shoot showed different elongations in each treatment. Root absorption treatment(3.01±0.48, 2.00±0.26) showed the shortest elongation in root and shoot than control(8.16±0.61, 4.03±0.48) and seed imbibition treatment(4.33±0.80, 2.48±0.36). It can be explained root tip meristematic cell activity was damaged by DNA methylation inhibitor. Primary root tips were collected in DW for 24 hours at low temperature(0℃) and fixed in fixation solution for 3 days to chromosome observation in mitosis. Mitotic index, chromosome structure and chromosome aberration were observed by phase-contrast microscope. Mitotic index of the control(0.29) showed twice mitotic cells as the treated groups(imbibition 0.15, absorption 0.14). Observation of chromosomes showed some short chromosomes and loosen chromosomes affected by zebularine. It is considered because of zebularine damage DNA in mitosis. We observed "gap by chromosome breakage" in chromosomes that have loose parts between centromere and telomere. It seems demethylation of zebularine occurs chromosome breakage.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.195-200
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• 1995

The design of this field experiment was a completely randomized block arrangement, consisted of 16 treatments (Gliricidia sepium provenances) and 6 blocks as replications with 12 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), and one each was from Colombia (C), Indonesia (I), Nicaragua (N), panama (P), Costa Rica (R), and Venezuela (V). After 12 months establishment the gliricidia were lopped regularly 4 times a year, twice during the 4 months wet season and twice during the 8 months dry season at 150 cm height. There was variation (p < 0.05) in stem elongation from 22 to 80 cm, leaf retained from 118 to 209%, branch number from 13 to 24, fodder yield from 1,015 to 1,671 g DW/plant and wood yield from 792 to 1,662 g DW/plant among the provenances; and such variations were affected by the seasons. Belen (N14), Retalhuleu (G14) and Bukit Bali (I) provenances were ranked first, second and third, respectively, measured in terms of leaf retention, stem elongation, fodder and wood yields during the wet and dry seasons.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.515-522
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• 1995

The field experiment was carried out to study the growth and fodder yield of the Gliricidia sepium provenances in fence system in dryland farming area in Bali, Indonesia for 24 months. The design of the experiment was a completely randomized block arrangement, consisted of 16 treatments (Gliricidia sepium provenances) and 12 blocks with 10 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), and one each was from Colombia (C), Indonesia (I), Nicaragna (N), Panama (P), Costa Rica (R) and Venezuela (V). After 40 weeks establishment the gliricidia were lopped regularly 4 times a year, twice during the four month wet season and twice during the eight month dry season at 150 cm height. There were variations (p < 0.05) in stem elongation from 10 to 121 cm, leaf retained from 48 to 105%, leaf shedding from 53 to 86%, branch number from 4 to 7, fodder yield from 281 to 648 g DW/plant, and wood yield from 53 to 179 g DW/plant; and such variations were affected by the seasons. Retalhuleu provenance of Guatemala (G14), Belen provenance of Nicaragua (N14) and Bukit Bali provenance of Indonesia (I) were ranked first, second and third, respectively, measured in terms of stem elongation, leaf retention, fodder and wood yields during the wet and dry seasons.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.106-113
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• 1997

A field experiment was carried out on a dryland farming area of southern Bali for 92 weeks, to study the growth and fodder yield of 16 provenances of Gliricidia sepium in guardrow system. The experimental design was completely randomized blocks of 16 treatments (Gliricidia sepium provenances) replicated 3 times, with 6 plants per provenance. Six provenances were from Mexico (M), four from Guatemala (G), and one each from Colombia (C), indonesia (I), Nicaragua (N), Panama (P), Costa Rica (R) and Venezuela (V). After 40 weeks establishment the gliricidia were lopped 4 times a year at 150 cm height, at 2 months intervals during the 4 month wet season and 4 month intervals during the 8 month dry season. Stem elongation varied from 21 to 81 cm, leaf retention from 39 to 240%, branch number from 12 to 35, fodder yield from 1,090 to 3,153 g DW/plant. and wood yield from 743 to 2,750 g DW/plant. Pontezuelo provenance of Colombia (C24), Belen provenance of Nicaragua (N14) and Retalhuleu provenance of Guatemala (G14) were ranked first, second and third, respectively, for stem elongation, leaf retention, fodder and wood yields, during the wet and dry seasons.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.222-230
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• 2018

This study aimed to determine effects of light-emitting diodes on plant growth, leaf morphology and cell elongation of two cultivars ('World-star' and 'Sushiro') of Spinacia oleracea. Plants were grown in a NFT system for 25 days after transplanting (DAT) under the LEDs [White (W), Red and Blue (RB, ratio 2:1), Blue (B), Red (R) LED] under the same light intensity and photoperiod ($130{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours). The 'World-star' variety was significantly higher in shoot fresh and dry weights, leaf number, and leaf area than the 'Sushiro' variety. For the 'World-star' variety, the two treatments of mixed light (RB) and red light (R) showed a 35% higher shoot dry weight than that of blue light (B) and white light (W) at 25 DAT. In the 'Sushiro' variety, mixed light (RB) treatment, which had the highest shoot fresh and dry weights, showed 40% higher than the white light (W) treatment, which had the lowest shoot fresh and dry weights. Both varieties showed leaf epinasty symptom at 21 DAT only in both mixed light (RB) and red light (R), and red light (R) treatment showed significantly higher symptom than mixed light (RB), indicating the leaf epinasty is associated with red light. Microscopic observations of the cell size in the leaf center and edge parts showed that the cell density of leaf edge under the red light (R) was lower than that in leaf center, supporting previous reports that suggest an association of the cell size difference between the leaf center and edge with the leaf epinasty occurrence. Since the blue light (B) plays a role in alleviating the epinasty symptom caused by the red light (R), it seems necessary to identify the appropriate mixing ratio of the two light sources. In addition, the World-star variety seems to be more suitable for the cultivation of plant factory using LED light sources.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.719-727
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• 2010

Reduced irradiance promotes shoot elongation depending on developmental stage and environmental factors and decreases plant quality in $Cyclamen$ $persicum$ Mill. To determine the petiole elongation responses to low irradiance, 'Metis Scarlet Red' cyclamen at different developmental stages [juvenile (5-6 unfolded leaves), transitional (1-3 visible flower buds), or mature (1-3 elongating peduncles)] was grown in growth modules at 60 (low light, LL) or 240 (high light, HL) ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD within the growth chambers at different temperatures [16/12 (low temperature, LT), 22/18 (medium temperature, MT), or 28/$24^{\circ}C$ (high temperature, HT) (day/night)]. In Experiment I, juvenile plants were either kept in an LL or HL module during the entire treatment of 4 weeks or were transferred to the other module at 1, 2, or 3 weeks after treatment in an MT chamber. In Experiment II, juvenile, transitional, or mature plants were moved to the HL module at 0, 3, 6, 9, or 12 days after being placed in the LL module at the MT chamber and grown for 21 days. In Experiment III, transitional plants were moved to the HL module at 0, 3, 6, 9, or 12 days after being placed in the LL module at the LT, MT, or HT chambers. As the exposure duration to LL increased from 0 to 4 weeks or from 0 to 12 days, petiole length and plant height increased at all temperatures and developmental stages. In Experiment I, the exposure to LL during the latter period, rather than the early period, increased elongation rate. In Experiment II, petiole elongation in transitional plants was more sensitive to LL than juvenile or mature plants during the early period of the treatment for 12 days. In Experiment III, petiole length increased with increasing temperature and exposure duration to LL. Petiole elongation rate at HT increased rapidly from the beginning of LL exposure as compared to LT. Increase of $6^{\circ}C$ in temperature had the similar effect to LL exposure for 3 days in petiole elongation. To conclude, transitional cyclamen under higher temperatures responds more immediately to low irradiance and elongates its petioles.

• Journal of Plant Biotechnology
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• v.39 no.2
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• pp.114-120
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• 2012

An efficient in vitro propagation was established by using axillary bud explants of roseroot (Rhodiola rosea L.), which has been known as a medicinal plant in East Asia. Among various media tested, MS medium supplemented with 1.0 mg/L BA and 1.0 mg/L $GA_3$ was found to be the best for multiple shoot formation (15 axillary shoots per axillary bud). In addition 1/2MS medium containing 50 g/L sucrose was best for shoot elongation (7.8 cm) and increasing total chlorophyll contents (8.64 mg/g) best. Maximum number of roots (17.7 roots per explant) was observed on the medium without plant growth regulators. Propagated plants were successfully acclimatized to ex vitro conditions, with a survival frequency of 97% after 12 weeks. Most rooted shoots grew well and produced viable seeds when grown in vitro culture conditions. Therefore, R. rosea can be effectively propagated in vitro by the system we developed in this study.

• Journal of Plant Biotechnology
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• v.35 no.3
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• pp.229-234
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• 2008

An efficient micropropagation was established by using axillary bud explants from two-year-old tree(Echinosphorea koreensis Nakai), which has been known as a rare and endangered species. Among various basal media tested, DKW medium was shown to be the best for axillary shoot elongation. The addition of both BA and TDZ to the medium induced 6 to 10 shoots per explant during eight weeks of culture, without showing any abnormal morphology at the shoot proliferation stage. However, high concentration of TDZ(>0.05 mg/L) appeared to cause hyperhydration on either leaf or shoot at the later developmental stage. Approximately 20% of shoots produced roots by the addition of 1.0 mg/L NAA but not by IBA($0.2{\sim}1.0$ mg/L). Ex vitro micro-cuttings were better source for root induction; up to 58.6% of the micro-cuttings rooted when 100 mg/L IBA was applied to the soil(vermiculite). More than 90% of plantlets with roots were successfully acclimatized and grew normally in the field. Therefore, we suggest that this endangered tree species can be effectively micropropagated by axillary bud culture system developed in this study.