• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.37-45
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• 2007

The genetic transformation of watermelon by Agrobacterium has been known very difficult and a few successful cases have been reported by obtaining the direct shoot formation. However, since this direct shoot formation is not guaranteed the stable transformation, the stable transformation with reproducibility is required by a different approach such as a callus induced manner. The best conditions for inducing the callus from cotyledon and root explants of watermelon were 2 mg/L zeatin + 0.1 mg/L IAA and 2 mg/L BA + 0.1 mg/L 2,4-D, respectively. The GFP expression in the callus was identified and monitored through fluorescent microscopy after transformation with pmGFP5-ER vector. Paromomycin rather than kanamycin was used for selecting the nptll gene expression because it was more effective to select the watermelon explants. Four different callus types were observed and the solid green callus showed stronger GFP expression. The highest frequency of GFP expression in the callus developed from cotyledon was 9.0% (WM8 inbred line), while the highest frequency from root was 8.3% (WM6 inbred line). The WMV-CP was transformed using the method of GFP transformation and the genetic transformation of WMV-CP was confirmed by PCR and Southern blot analysis. Here we present a system for callus induction of watermelon explant and the callus induced method would facilitate the establishment of stable watermelon transformation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.1-10
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• 2011

This study was conducted to compare the growth of Zoysia japonica depending on different soil treatments in Saemangeum sea dike, which is filled with dredged soil. Zoysia japonica was planted using sod-pitching method on the control plot. On plots which were treated with forest soil and soil improvement, Zoysia japonica seeds were sprayed mechanically. Sixteen months after planting, coverage rate, leaf length, leaf width, and root length were measured and analyzed. Also, three Zoysia japonica samples per plot were collected to analyze nutrient contents. Coverage rate was 100% in B treatment plot(dredged soil+$40kg/m^3$ soil improvement+forest soil), in C treatment plots (dredged soil+$60kg/m^3$ soil improvement+forest soil), and D treatment plots (dredged soil+$60kg/m^3$ soil improvement), while only 43% of the soil surface was covered with Zoysia japonica on control plots. The width of the leaf on C treatment plots (3.79mm) was the highest followed by D treatment (3.49mm), B treatment (2.40mm) and control plots (1.97mm). Leaf and root length of D treatment was 30.18cm and 13.18cm, which were highest among different treatments. The leaf length of D treatment was highest followed by C, B, and A treatments. The root length of D treatment was highest followed by C, A, and B treatments. The nitrogen and phosphate contents of the above ground part of Zoysia japonica were highest in C treatment, followed by D, B, and A treatments. The nitrogen and phosphate contents of the underground part of Zoysia japonica were highest in D treatment, followed by C, A, and B treatments. C and D treatments showed the best results in every aspect of grass growth. The results of this study could be used to identify the cost effective way to improve soil quality for soil surface fixation on reclaimed areas using grass species.

• Applied Microscopy
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• v.32 no.4
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• pp.319-327
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• 2002

Salvinia natans, an unique water fern having a small rootless body, developed three different types of trichomes throughout the plant. The most peculiar type exhibiting rows of obvious, whitish, multicellular trichome clusters was noticed in the upper surface of the floating leaves. Eight to ten branches within a cluster extended ca. $370{\sim}420{\mu}m$ from the leaf surface. No stalk cell was found, however, four large epidermal cells were discernable at the base of four central branches in the cluster. Each branch consisted of $8{\sim}10$ obliquely-oriented small cells that gradually decreased in size toward the branch tip. The second type was found in the lower surface of the floating leaves, stems, and sporocarps. Multicellular uniseriate trichomes, ca. $430{\sim}980{\mu}m$ long, were distributed all over these structures. The tip of trichome was acicular, but a semi-spheric protuberance of approximately $24{\sim}32{\mu}m$ in diameter occurred at the base of each trichome. The protuberance appeared to be firmly attached to the side of the basal cell, however, internal connection to the trichome cell itself was uncertain. The third type was similar to the second in that multicellur uniseriate trichomes with acicular tip and a protuberance at the base were present. However, the trichomes were considerably long relative to the second type, and only occurred along the surface of highly dissected, submerged leaves. A majority of the trichomes exceeded more than 2 mm in length that hung downward in the water. Regardless of trichome type, all trichomes contained a huge central vacuole with very thin cytoplasm, resulting from the fusion of several vacuoles during early trichome development. The various densely-distributed trichomes formed in Salvinia natans probably play an important role in plant buoyancy.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.156-160
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• 2010

This study was performed to provide useful information for kentucky bluegrass management during summer by application of plant growth regulator, Trinexapac-ethyl. Visual quality, shoot density and chlorophyll contents of treatment blocks were significantly different from those of control during summer by application of Trinexapac-ethyl. The turfgrass density of treatment was increased of 4ea/$10\;cm^2$, especially about 5ea/$10\;cm^2$ during the growth retarded period of June and July. Chlorophyll contents index and visual quality of kentucky bluegrass were improved by application of Trinexapac-ethyl during summer, too. In addition, the occurrence of foliage in rainy and high temperature season was less than that of control. However, there was no significant difference in the root length of Kentucky Bluegrass. Meanwhiles, mowing height of kentucky Bluegrass was suppressed by 38% at 2 WAT week after treatment and that there was no significant growth of treatment at 4 WAT. In this experiment, turfgrass quality was significantly better than that of control during July, even though trinexapac-ethyl wasn't applied at all in July. Consequently, periodic treatment of trinexapac- ethyl from spring would be very important to promote the turfgrass visual quality during summer which is unfavorable season on the growth of kentucky bluegrass. And it is possible to reduce mowing times at least 30% for 2 weeks by one application of Trinexapac-ethyl 0.02~0.03 ml/$m^2$ in kentucky bluegrass fairway. Additively, trinexapac- ethyl treatment can be helpful environmentally by cutting down the fertilizers and pesticides in golf course.

• Journal of Environmental Impact Assessment
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• v.31 no.5
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• pp.296-309
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• 2022

This study investigated the mobility of inorganic elements (As, Cd, Pb, and Zn) that existed as acid extractable and reducible forms in flooded soils with a pot experiment involving rice cultivation. In general, it is known that soil inorganic elements that existed as an acid extractable form which includes exchangeable, carbonates, non-specifically sorbed, and specifically sorbed have mobility. However, the result of the experiment revealed that each inorganic elements of rice roots grown from flooded soils had different characteristics. The concentrations of Arsenic existed as both forms and the concentrations of cadmium and lead existed as a reducible form in the soils showed a high causal relationship with the concentrations of those elements in the roots of rice plants. The concentrations of zinc, an essential plant element, didn't show a causal relationship. Therefore it is necessary to consider the soil's environmental characteristics such as drained/flooded condition, oxidation/reduction condition, etc. for the mobility assessment of inorganic elements. The concentrations of the reducible form of arsenic, cadmium, and lead in flooded environment such as a paddy field should be also considered because the mobility of these elements combined with Fe/Mn increases in the reduction condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.146-157
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• 1994

Wasong(Orostachys japonicus A. Berger) has been used as anti-cancer medicinal plants from ancient time. This experiment was conducted to obtain some fundamental informations concerning anatomical study, germination test, soil analysis of indigenious districks, adaptaion of soil for wasong. The leaf of wasong was xerotype with spine, mesophyl chloroplast is dense surrounded vascular bundle, with a many large water storage tissue without chloroplast, and was bifacial stomata leaf type. The stem of wasong was amphicribral vascular bundle, central cylinder was cylinder type and protostele. Root was polarch type, potoxylem of it's was arranged in ring shape of annulation and metaxylem. The structure of flower was cymose, was caylyx of 5 sepals, corolla of 5 petals, roecium of 10 stames, ovules of five, placentation parietal, ovary superior, axile placenta. The optimum temperature for seed germination was $25^{\circ}C$ under light and germination percentage was 22.5%. Dormancy breaking was effective for 6-8 days at 5$^{\circ}C$ and at 100 ppm level of $GA_3$ The soil analysis of wasong local districks, content of available $P_2O_5$, Ca were higer than optimal level of upland and C.E.C., exchangeable k was not significantly different of that, but exchangeable magnesium was very low. The growth of wasong was affected draining regardless soil combination treatment.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.249-254
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• 1999

The effects of various levels of Al concentration on growth, nutrient status and net photosynthetic rate of 2-year-old Pinus densiflora Sieb. et Zucc. seedlings grown in a nutrient culture solution were investigated. Al concentrations were added as aluminum chloride($AlCl_3$) at 0(control), 10, 30 and 60ppm to the nutrient culture solution. The nutrient culture solution was maintained at pH 4.0 by adding HCl or NaOH solution. The seedlings were transplanted into the nutrient culture solution and grown in a greenhouse for 90 days from May 8 to August 6, 1996. The treatment above 10ppm of Al concentrations induced a significant reduction on the dry weight growth of the seedlings. The relative growth rate(RGR), net assimilation rate(NAR) and net photosynthetic rate of the seedlings were reduced with increasing of Al concentrations in the nutrient culture solutions. This result suggests that reductions in the RGR and NAR of the seedlings were mainly due to the inhibition of net photosynthesis. In addition, the increase of Al concentrations in a nutrient culture solution decreased the concentration of essential mineral elements such as Ca and Mg in the needle of the seedlings. However, the concentrations of Al of each plant organ increased in the treatment above 10ppm of Al concentrations in the nutrient culture solutions. This result suggests that the increased Al concentration in the belowground part resulted from the decreased concentration of essential mineral elements in the aboveground part of the seedlings.

• Journal of Plant Biotechnology
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• v.36 no.1
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• pp.23-29
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• 2009

We have previously isolated a CCCH type zinc-finger protein gene, OsZF2 (Oryza sativa Zinc Finger 2), from the cold-treated rice cDNA library. To investigate the potential role of OsZF2, transgenic rice lines over-expressing OsZF2 under the control of CaMV 35S promoter have been developed through Agrobacterium-mediated transformation. Elevated level of OsZF2 transcripts was confirmed by RNA gel blot analysis in transgenic rice. Under the 100 mM NaCl condition, the transgenic rice showed significantly enhanced growth rate in terms of shoot length and fresh weight, implicating that OsZF2 is likely to be involved in salt response of rice. In the field condition, however, the transgenic rice showed a dwarf phenotype and flowering time was delayed. Genome expression profiling analysis of transgenic plants using the 20K NSF rice oligonucleotide array revealed many up-regulated genes related to stress responses and signaling pathways such as chaperone protein dnaJ 72, salt stress-induced protein, PR protein, disease resistance proteins RPM1 and Cf2/Cf5 disease resistance protein, carbohydrate/ sugar transporter, OsWAK kinase, brassinosteroid LRR receptor kinase, and jasmonate O-methyltransferase. These data suggest that the CCCH type zinc-finger protein OsZF2 is a upstream transcriptional factor regulating growth and stress responsiveness of rice.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.175-179
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• 2005

To develop a high efficiency plant regeneration system from in vitro cultures of strawberry, cv. Yeobong, petiole and leaf explants were cultured on MS basal medium containing a combination of 0.5 mg/L IBA and 3.2 mg/L kinetin or zeatin or benzyl amino purine (BAP) for 6 weeks, and leaf explants with dark pretreatment for a week ($T_1$), 2 weeks ($T_2$), and 4 weeks ($T_3$) were cultured on medium supplemented with 0.5 mg/L IBA and 3.2 mg/L zeatin under 16 hr photoperiod for 6 weeks. Shoot organogenesis was observed from the greenish calli containing minimal anthocyanin formed at proximal cutting edges of the leaf explant (57%) when cultured adaxial side on the medium, whereas was directly formed from a cutting edges of petiole explant (6.3%). Frequency of callus formation and shoot organogenesis at large size of leaf explant ($1.0{\sim}1.5\;cm^2$) was higher than small size ($0.5{\sim}1.0\;cm^2$), and dark pretreatment significantly improved the frequency of leaf explants that produced calli and shoots. The maximum frequency (87%) for shoot organogenesis was obtained from the leaf explants that transferred to a 16 hr photoperiod condition after the initial 4 weeks dark period. The improved frequency (87%) in comparision with control without dark pretreatment (27%). When the shoots were transferred to 1/2 MS basal medium, formed roots with 20 d of culture. The rooted plants were subsequently transferred to the pots and to the field.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.40-40
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• 2021

곤달비(Ligularia stenocephala)는 쌍떡잎식물, 국화과의 다년생 초본식물로서 한국·일본·타이완·중국 등에 분포하고, 우리나라는 전남 홍도가 특산 자생지이며 주로 강원도, 경북 경주, 전북 남원 등지에서 재배되고 있다. 곤달비는 어린 부분을 생채, 데친 나물, 국거리, 튀김, 묵나물로 식용한다. 특수 성분으로는 Isopropenyl, dimethoxybenzofuran, Liguhodgsonal, Ligujapon, Ligularinone A, Ligularinone B 등이며 신경을 안정시키는 진정작용, 진통억제, 정기를 보익하고 허약함을 보하는 기능이 있고, 한방에서는 뿌리가 신경통, 유종(乳腫) 등에 쓰인다. 곤달비는 주로 시설하우스나 노동력이 많이 드는 임간에서 재배되어 생산 단가가 높아 소비활성화를 위한 가공제품을 생산하기가 힘들며, 육묘 또한 시설하우스에서 주로 이뤄지고 있다. 본 연구는 곤달비 노지육묘 파종시기별 생육특성을 구명하여 노지재배 생력화 재배기술을 확립하고자 2019년 4월부터 2020년 11월까지 전라북도농업기술원 허브산채시험장(해발 500m)에서 수행하였다. 춘파는 2019년 4월 상순, 5월 상순, 6월 상순에 각각 파종하였고 추파는 2019년 9월 상순, 중순, 하순에 파종하였다. 본포 정식은 춘파는 2019년 6월 말에, 추파는 2020년 4월 말에 식재하였으며, 파종시기별 발아율, 활착률, 생육특성, 수량성 등을 조사한 결과 파종시기별 발아율은 춘파가 35.0%로 추파 30.7%보다 높았으며, 발아 소요일수는 추파 육묘에서 8.3일로 춘파 육묘 9.3일보다 빨랐다. 파종시기별 정식시 묘소질은 춘파가 추파보다 좋은 생육상태를 보였고, 정식 후 육묘 활착률은 추파가 99.3%로 춘파 94%보다 높았고, 생존율 또한 추파 육묘에서 99.3%로 춘파 육묘 96.3%보다 높았다. 파종시기별 생육특성은 처리간 유의한 차이는 없지만 춘파에서 좀 더 좋은 생육을 보였으며, 수확량은 춘파 처리구에서 798.6kg/10a로 추파 처리 621.4kg/10a보다 높았다.