• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.473-479
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• 1994

A seed coating system was developed to screen non-viable seeds in the Brassicaceae. The crops studied were radish, chinese cabbage, broccoli, cauliflower and brussel sprout. Sinapine leaked more from artificially deteriorated seeds than non-deteriorated seeds. Seed coating with cellulose was to trap the sinapine leakage in the non-viable Brassicaceae vegetable seeds. The seeds were first hydrated, then coated with cellulose powder to capture the leakage. Coated seeds were dried, then sorted two fractions-fluorescent seeds and non-fluorescent seeds under the UV light. The ratio of the fluorescent seeds were higher in bad seedlot than good one. The germination rate were increased 3∼35% by eliminating the fluorescent seeds in tested Brassica vegetable seeds. Sowing non-fluorescent seeds resulted in a greater percent normal seedling than non-coated seeds in all seedlots. The fluorescent seeds contained a high percentage of the dead and abnormal seedlings.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.112-118
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• 1994

Forth microbial isolates out of 167 isolates from the soil of controlled cultivation areas inhibited mycelial growth of Rhizoctonia solani AG2-1 causing the strawberry bud rot in vitro. Among the isolates, Kr013 and Kr020 showed suppressive effect to R. solani AG2-1 on seedlings of chinese cabbage treated by root immersion, charcoal carrier granule and drenching on 1.0% infested soil in pot. Furthemore, the corresponding effect was also revealed when the charcoal carrier granule of the isolates were treated on the seedling of strawberry that were planted on the planting hole in pot. To examine the effects of biological control in green house, it had been tested the infection rates by using two different treatments. First, the strawberry runner were planted on the nursery soil mixed with 20% charcoal carrier granule of Kr013 and Kr020 isolate respectively, and grown for 20 days before transplanting. Then the young plants form the mother plant were separated and transplanted on the 1.0% infested soil. Another method was that the charcoal carrier of Kr013 and Kr020 isolates applied to planting hole of 1.0% infested soil just before transplanting. Then the young plants were grown for 20 days on the sterilized nursery soil before transplanting. From the results, the effects of biological control was significantly higher on former treatment (e.g. the infection rates were 7.3 and 5.7%, respectively) than on the latter treatment (e.g. the corresponding value were 16.7 and 15.7%, respectively). The antagonistic isolates of Kr013 and Kr020 were respectively identified as Pseudomonas cepacia with the similarity of 55.0% and 60.0% by using the Biolog GN Microplate system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.49-53
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• 1998

Direct-seeding has major advantages such as labor and cost saving by eliminating preparation of seed bed and transplanting. But, it required increased input of fertilizers and pesticides because of the extended paddy period. Direct seeding in wet paddy (DSWP) gives faster growth and more uniform seedling emergence than direct-seeding in dry paddy. This research had an objective to develop an efficient N management practices for DSWP with split application of N fertilizer. A paddy field experiment was conducted to evaluate effects of starter N and N-topdressing which was delayed N application until 5-leaf stage, with comparison to transplanting (TP). Total amount of N application were two levels; 110kg and 77kg/ha. The N applications were split four times during rice growth stages; starter, topdressing at 5-leaf stage, top dressing at tillering stage, and topdressing at panicle initiation stage. DSWP had more tillers/$m^2$ than TP, but with the delayed heading. The DSWP plots which received N-topdressing at 5-leaf stage without starter N had higher leaf area index (LAI) and leaf greenness than the TP plot. Also, these DSWP plots had high leaf-N concentration at the heading stage, as calculated from leaf chlorophyll meter readings. Rice yield in DSWP with N-topdressing at 5-leaf stage was significantly higher than that in TP and in DSWP with starter N. Energy and N use efficiency were improved in DSWP with N-topdressing at 5-leaf stage. But, there were no significant differences in grain yield between the two levels of total amounts of N applications, 77kg and 110kg/ha. We concluded that starter N could not be used effectively by rice seedlings, but topdressing N at 5-leaf stage was an efficient N management for rice growth and yield in DSWP system.

• Mycobiology
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• v.39 no.3
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• pp.206-218
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• 2011

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vitro germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vitro germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.351-359
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• 1997

Antifungal activities of the crude extracts of Anemarrhena asphodeloides. Coptis japonica and Phellodendron amurense were tested against Phvtophthora capsici. and the control effect on red-pepper phytophthora hlight and phytotoxicities of red-pepper were investigated. The results were summarized as follows; Mycelial growth and zoosporangial germination of the red-peppcr phytophthora hlight organism P. capsici were inhihited hy thc crude extracts of plant materials. Methanol extracts or plant materials had hctter antifungal activity than water extracts at hoth a room temperature and a hoiling condition. Antifungal activities of three crude extracts were gradually decreased with prolonged storage period. Red-pepper phytophthora hlight was effectively controlled hy the crude extracts of three plant materials. Of these. the crude extract of C. japonica was marvelously effective. Phytotoxic symptom to red-pepper seedling showed hy water cultural method hut not by pot test. Seed germination and radicle growth of red-pepper were inhihited hy the crude extracts of three plant materials. Phytotoxic symptoms in the leaves and fruits of red-pepper were not ohserved with exogenous foliage application of the three crude extracts.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.394-402
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• 2009

Adventitious shoots were induced from pinnae, petiole and rhizome in Pteris cretica 'Wilsonii' in order to develop the efficient mass propagation method, using in vitro culture. Only homogenized rhizome segments could regenerate young sporophytes. Efficient regeneration of multiple shoots was obtained on the one-eighth strength MS medium containing 1% sucrose, and $50mg{\cdot}L^{-1}$ $NaH_2PO_4$. To achieve higher rate of regeneration from rhizome segments, rhizome segments were exposed to growth regulators for 2 months and then subcultured on hormone-free medium. The greatest shoot regeneration was obtained by $1{\mu}M$ kinetin with $5{\mu}M$ NAA. BA was effective in formation of GGB (kind of meristems), but they showed low shoot regeneration rate. Plants obtained from present experiments were transplanted to examine good environmental conditions for acclimation. Juvenile plants obtained by the one-eighth strength MS medium showed highest survival rate and vigorous growth at the seedling stage.

• Journal of Forest and Environmental Science
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• v.25 no.3
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• pp.167-175
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• 2009

An exploratory study was conducted in Juri Forest Range-2, a proposed biodiversity conservation area of Bangladesh to explore the present growing stock of tree, regeneration condition and status of non-timber forest products (NTFPs). This conservation area contains both natural and artificial plantation was selected by using multistage random sampling method. For determination of plot size and sampling methods, the quadrate size ($10m{\times}10m$) for tree stock measurement, ($2m{\times}2m$) for regeneration survey, ($20m{\times}20m$) for NTFPs survey was determined. Regarding tree stock survey, 14 species under eight families were found where Tectona grandis shows average number of stem/ha was 624 and basal area/ha was (10.36 $m^2/ha$) followed by Acacia auriculiformis (0.2 $m^2/ha$ and 637 stem/ha), Gmelina arborea (0.2 $m^2/ha$ and 600 stem/ha). In regeneration survey, 14 species were found belonging to 9 families where Alstonia scholaris shows highest (3,750) seedling per hectare. Regarding NTFPs, bamboo and cane are the most common resources. In last ten years, the total timber output was 1,28,596.14 cubic feet and total amount of revenue was 4,64,434 US$. The vacant area is 1,335.5 acre which contains 14% of total area. If this vacant area is planted with suitable species and take proper steps for appropriate management of this species it will be a good biologically diversified area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.83-87
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• 1965

This experiment was done to observe the morphological change of plant under the cultivation of deep ploughing and heavy fertilization with paddy rice 1963 at Seoul. A seedling of 35 days old was transplanted June 1st, in a galvanized iron pot with botton 20 cm in diameter, which was painted white inside and filled with sand mixed with fertilizers. The treatments were 15cm soil depth of normal fertilization, 30cm of fertilization twice and 45cm of fertilization thrice. Replications were three. The plant was observed on main stem Aug. 6 before heading, Sep. 12 after heading and Oct. 17 at the time of harvest at the same pot. The results are as follows. The length and the width of leaf blades of the upper part on main stem have the tendency to be big and vigorous with the deep ploughing and heavy fertilizations(Fig 1, 2, 3 and 4). The number and the size of vascular bundles of main stem is to increase when the paddy is cultivated with the method of deep ploughing and heavy fertilizations(Fig 5). The number and the weight of roots of main stem increases with deep ploughing and heavy fertilizations(Fig 6).

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.323-330
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• 2021

Zygotic embryo culture was performed to propagate evergreen oak, Quercus myrsinifolia, which has recalcitrant seeds and is difficult to propagate by cuttings. Zygotic embryos appeared in WPM medium after 14 days, and after 56 days, they developed into complete plants with cotyledons and roots. The medium suitable for zygotic embryo culture was 1/4 WPM medium, showing a shoot growth of 2.43 cm and root growth of 8.7 cm after 8 weeks of culture. As a result of investigating the effect of GA₃ on the growth of plants germinated from zygotic embryos through GA₃ treatment, the best growth was shown in 0.5 mg/l GA₃ treatment. The in vitro rooting and growth of IBA-treated zygotic embryo-derived plants were good in the 0.5 mg/l IBA treatment and rooting and shoot growth were not observed at higher concentrations. And the callus induction rate also increased as the concentration of IBA increased. Plants grown in vitro were transferred to a plastic pot containing artificial soil and acclimatized in a greenhouse for about 4 weeks, resulting in more than 90% survival. As a result of this study, the zygotic embryo culture method was confirmed to be effective for mass propagation of Q. myrsinifolia. The results of this study are expected to contribute significantly to the mass propagation of elite Q. myrsinifolia.

• Korean Journal of Environmental Agriculture
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• v.42 no.3
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• pp.177-183
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• 2023

Rendering, is attracting attention as a technology that can stably and quickly process livestock carcasses. However, large amounts of livestock carcass solid residues are discharged in this process and limited methods are available for recycling them. In this study, rendered animal carcass solid residues were pyrolyzed to produce carbonized materials (350℃; RACR-C) and their chemical properties were investigated. Further, RACR-C were applied to cabbage cultivation for investigating their crop growth characteristics and soil improvement effects. RACR-C contained large amounts of fertilizer components such as nitrogen and phosphorus, and showed no toxic effects on the seedling growth of crops. The content of water-soluble nutrients released from RACR-C under the reaction time increased rapidly within 30 min, but was insignificant compared to the total content. Thus, most fertilizer components in RACR-C were not readily soluble in water. The optimal application amount for applying RACR-C to cabbage cultivation based on the changes in cabbage growth, inorganic content, and soil chemistry was 200 kg/10a. Overall, pyrolysis of solid residues after rendering livestock carcass to produce carbonized material as a soil improver is an effective method to recycle the waste discharged from the rendering process.