• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.74-81
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• 1985

Dimension analysis was used to estimate biomass and net primary production(NPP) in a 36-year-old Japanese red pine (Pines densiflora S. et Z.) natural forest in Kangwondo. Best estimation was made by the equation model of $Wt=aD^bH^c$ where Wt is weight in kg, D is DBH in cm, and H is total tree height in m. Total aboveground biomass was estimated at 198.82 t/ha. Organic matter was distributed in the Japanese red pine stand as follows ; bolewood 68.8%, live branches 16.5%, bolebark 5.4%, foliage 4.6%, dead branches 3.7%, and cones 0.6%. Net primary production was estimated at 15.87 t/㏊/yr and was distributed: bolewood 44.5%, live branches 30.9%, foliage 14.1%, current twig 7.1%, and bolebark 3.3%. Leaf efficiency was estimated at 1.876. The power equation for biomass and IVPP yielded similar results as the results for Pines densiflora in Japan.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.822-824
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• 2007

The efficient system for plant regeneration from cotyledon and primary feat explants of lettuce was established. Plant regeneration efficiency was shown 91.3% from cotyledon and 85.9% from primary leaf explants of variety 'Jungtongpogi' in KN medium. Plant regeneration efficiency was also estimated with various plant regeneration media in variety' Chungchima', which was lowest plant regeneration efficient showing 35.4% from cotyledon and 30.3% from prima leaf explants in KN medium. Kl medium increased 77.9% and 80.7% of plant regeneration efficiencies from cotyledon and primary leaf explants of variety 'Jungtongpogi' were cultured on KN medium. In case of varie쇼 ‘Chungchima', efficient plant regeneration was shown when primary leaf explants were cultured on SH and KI media.

• Asian Journal of Turfgrass Science
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• v.1 no.1
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• pp.7-17
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• 1987

The experiment with two levels of nitrogen (0. and 300kg / ha / year) and two levels of clipping height (1.5cm and 4cm) was conducted on the field during the period 3 June to 23 October 1985. Clonal lines of korean lawngrass ( Zoysia japonica Steud.) and manilagrass ( Zoysia matrella ( L.) Merr.)of Daejon origin were established in June, as individual clone in rows 30cm apart with a 40cm spacing between clones, actually 4 clones each plot. The results obtained were as follows : 1. When no nitrogen was applied to korean lawngrass, leaf blade which appeared during the August / early September period remained green for a period of about 10 weeks and even leaves emerged in late September lived for 42 days. However, leaf longevity did not exceed 8 weeks as nitrogen was applied. In contrast the leaf longevity of manilagrass which emerged during the mid - August / early September period was 11 weeks and, under the nitrogen applied, 9 weeks, indicating that the life - saen of individual leaf of manilagrass may be longer than that of korean lawngrass. Meanwhile, clipping height had no effect on the leaf longevity in both grasses. 2. During the July / August period, tiller number, green leaf number and DM weight of korean lawngrass were increased significantly with fertilizer nitrogen, but were not with two levels of clipping height. This trend was reversed after late September : no effect of nitrogen was appeared. Instead, lax clipping increased tiller number, green leaf number and DM weight. Green leaves stimulated by lax clipping resulted in the occurrance of more dead leaves in late October. 3. The increase of tiller number, green leaf number, and DM weight of korean lawngrass due to nitrogen application appeared to be of significance in early September. Unlike korean lawngrass, however, this significant increase was maintained to late October when new green leaves still emerge. Clipping height had little effect on the growth of manilagrass by early September, but since then, lax clipping stimulated leaf appearance, possibly resulting in a remained green color of manilagrass turf. 4. Among the stolons outgrown until early September, the primary stolon was not influenced by nitrogen and clipping treatments to produce only 2 - 3 stolons. However, 1st branch stolon as affected by nitrogen increased significantly, so most of stolons which occurred consisted of 1st branch stolon. 5. Until early September, stolon length obtained at nil nitrogen level was chiefly caused by lengthening the primary stolons. By applying nitrogen the primary stolons of korean lawngrass was longer than 1st branch stolons when severe clipping was involved and in turn, shorter than 1st branch stolons when lax clipping was concerned. In manilagrass, 1st branch stolons were much longer than the primary stolons when turf was clipped severely but in conditions of lax clipping, there was little difference in length between primary and 1st branch stolons. 6. Stolon nodes of both korean lawngrass and manilagrass were positively influenced by nitrogen, but no particular increases by imposing clipping height treatment was marked in manilagrass. Although the stolon of korean lawngrass was grown until late october, the growth stimulated by nitrogen was not so remarkable as to exceed that a by nil N. 7. The thickness of korean lawngrass and manilagrass was greatest in late September, but that of manilagrass did not differ significantly from that in late October. 8. The response of stolon length of korean lawngrass to lax clippings was not so great in late October as to that to severe clippings. On the other hand, the positive effect of lax clippings to stolon length in m anilagrass was confirmed even in late October.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.15-20
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• 2011

This study was conducted to estimate the aboveground biomass and net primary production of 40 year old Pinus rigida forest in Sancheong, Gyeongnam province. The aboveground biomass was $127.7Mg\;ha^{-1}$ and $103.1Mg\;ha^{-1}$ of which were found from stem, $17.2Mg\;ha^{-1}$ from branch and $7.4Mg\;ha^{-1}$ from leaf. Biomass distribution ratio of Pinus rigida stands showed the highest in stem wood with 71.1%, followed by the branch with 13.5%, stem bark with 9.6% and lastly the leaf with 5.8%. Net primary production of aboveground biomass was $10.4Mg\;ha^{-1}$ and $3.6Mg\;ha^{-1}$ were found from stem, $2.2Mg\;ha^{-1}$ from branch, $1.3Mg\;ha^{-1}$ from twig and $2.8Mg\;ha^{-1}$ from leaf. Net primary production distribution ratio of Pinus rigida was 34.6% on stem wood, 26.9 on leaf, 21.2% on branch, 12.5% on twig and 4.8% on stem bark.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.364-377
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• 2020

Sugarcane is an important sugar crop contributes more than 80% of world sugar production. Mosaic, leaf fleck, and yellow leaf (YL) are the major viral diseases affecting sugarcane, amongst YL occurrence is widely reported in all the sugarcane growing countries. It is caused by Sugarcane yellow leaf virus (SCYLV) and detailed works were done on complete genome characterization, transmission, and management. However, in countries like Egypt, South Africa, Cuba, Mauritius and Hawaii, the disease was reported to the cause of sugarcane yellow leaf phytoplasma (SCYP) and/or SCYLV as single/combined infections. Hence, we have investigated in detail to identify the exact Candidatus phytoplasma taxon associated in Indian cultivars affected with YL. The sequencing results and the restriction fragment length polymorphism pattern of the PCR products using the universal phytoplasma primers confirmed presence of sugarcane grassy shoot (SCGS) phytoplasma (16SrXI group) in the YL-affected plants. Mixed infection of SCYLV and SCGS phytoplasma was estimated as 32.8% in YL affected plants. Evolutionary genetic relationship between SCYP and SCGS phytoplasma representatively taken from different countries showed that SCYP from South Africa and Cuba were diverged from others and had a highest similarity with SCGS phytoplasma. Although we wanted to identify SCYP from YL affected Indian sugarcane cultivars, the study clearly indicated a clear absence of SCYP in YL affected plants and we found SCYLV as the primary cause for the disease.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.9-15
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• 2007

A comparative study of the structure and organization of the primary and secondary walls in different types of tropical plant waste fibers was carried out using transmission electron microscopy (TEM). The thickness of each layer was also measured using Image Analyzer. TEM micrographs haveconfirmed that cell wall structure of all six types of tropical plant waste fibers (empty fruit bunch, oil palm frond, oil palm trunk, coir, banana stem and pineapple leaf) has the same ultrastructure with wood fibre. The fibers consisted of middle lamella, primary and thick secondary wall with different thickness for different types of fibers. The secondary wall was differentiated into a $S_1$ layer, a unique multi-lamellae $S_2$ layer, and $S_3$ layer.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.210-215
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• 2002

Four field experiments were carried out from 1998 to 1999 and from 1999 to 2000 growing seasons of potato to investigate the relationship between leafminers and Alternaria alternata. The experiments established differential susceptibility among potato varieties to alternaria leaf necrosis, relationship between leafminer infestation and the level of necrosis, use of insecticides to reduce leafminer and leaf necrosis damages, and use of polyester fleece to eliminate leafminer and eventually reduce leaf necrosis. Results of the study indicate that control of leafminer is of primary importance because this will automatically lead to control of the damage caused by A. alternata.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.174-181
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• 1992

Early, mid, and late maturing soybean varieties were artificially infested with larvae of Delia platura at seeding, and then later development and productivity of soybeans were studied. In addition, in hope to utilize as possible tactics in the management of D. platura in soybeans, cultural factors such as contents of organic matter in soil, soil types, and the use of plastic mulching on the degree of damage to soybean plants by D. platura were examined. Primary leaf damage by the larva delayed the forthcoming vegetative growth but not the blooming which is initiated by the change in day length. Degree of delay in growth was more severe where leaf damage was induced by insect infestation than where artificially excised, apparently owing to simultaneous damage in stems and roots besides primary leaves. Productivity of soybeans also dropped significantly in plants with 25 % or more loss in the primary leaf area by the larva. Both transparent and black plastic mulchings shortened the period from seeding to emergence of soybean thus reducing the chance of possible attack by the larva. Soybean seedlings grown in clay loam or clay were attacked less by the larva than those in other types of soil. High organic matter content in the soil enhanced speed of emergence resulting in less larval damage to the seedling.

• Korean Journal of Plant Tissue Culture
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• v.21 no.1
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• pp.35-39
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• 1994

Is obtain cell lines showing high level of rice cold tolerance, direct in vitro selection through cold stress on primary pollen callus derived from anther culture was carried out Genotypic difference in callus formation and plant regeneration was recognized Rates of albino was increased along the duration of cold stress. Reciprocal effects were not noticed in anther culturability There was no variants related to rice leaf discoloration in pollen derived lines from parental varieties, regardless of days of cold stress. The regeneration and recombination of rice leaf discoloration in 146 pollen-derived lines, 70 pollen-derived lines from cold stress at $0^{\circ}C$ for 10 days, and 830 F$_2$ plants presented normal distribution curves with skewness in tolerance and no significant difference among 3 populations. Direct in vitro selection for rice cold tolerance through cold stress on primary pollen callus derived from anther culture, therefore, was revealed ineffective as a in vitro technology.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.285-290
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• 1987

Septoria brown spot caused by Septoria glycines Hemmi is one of the serious fungal diseases in soybean. Since little has been known about the disease progress in the field, the present study was conducted to determine the factors affecting the disease progress in the soybean plant. Disease severity and pattern of the progress of the Septoria brown spot were different with varieties. Susceptibility of soybean plants increased with increase of plant age and leaf maturity in order from the primary leaf to the newly expanded leaf. It seemed to be related with conidial germination on the leaves. Germination and germtube elongation were more inhibited by the diffusates obtained from upper leaves than those from lower leaves and they were higher in a susceptible variety than in a moderately resistant one.