• Korean Journal of Weed Science
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• v.15 no.4
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• pp.270-277
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• 1995

The research was carried out in tray in greenhouse equipped with Auto Foggy Systems(SAE KI RIN Co.) and the results were summarized as follows. 1. The number of leaves and fresh weight of Chinese cabbage were not different, but the plant height was increased due to foggy condition. 2. Plant height was decreased in 40 and 60 days of weed competition by foggy condition, the number of leaves was not different. And, shoot fresh weight was decreased by in all the duration of weed competition under foggy condition. Especially, that was greater in 40 days. 3. The shoot fresh weight was decreased by pendimethaline and napropamide application under foggy condition. Also, the number of leaves was decreased at 60 days after transplanting by pendimethaline application under foggy condition. 4. Pendimethalin, napropamide and alachlor treatments were not different in the weeding efficacy between non-foggy and foggy conditions. Trifluraline showed lower weeding efficacy by seedling emergence of large crabgrass as the days of treatment got longer under foggy condition.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.11-20
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• 2017

The objective of this study was to determine whether inoculation with Bacillus licheniformis MH48 as a plant growth-promoting rhizobacterium (PGPR) could promote nutrient uptake of seedlings of the ornamental plant Camellia japonica in the Saemangeum reclaimed coastal land in Korea. B. licheniformis MH48 inoculation increased total nitrogen and phosphorus content in soils by 2.2 and 20.0 fold, respectively, compared to those without bacterial inoculation. In addition, B. licheniformis MH48 produced auxin, which promoted the formation of lateral roots and root hairs, decreased production of growth-inhibiting ethylene, and alleviated salt stress. Total nitrogen and phosphorus uptake of seedlings subjected to bacterial inoculation was 2.3 and 3.6 fold higher, respectively, than the control. However, B. licheniformis MH48 inoculation had no significant effect on the growth of seedlings. Our results suggest that inoculation with B. licheniformis MH48 can be used as a PGPR bio - enhancer to stimulate fine root development, promote nutrient uptake and alleviate salt stress in ornamental plant seedlings grown in the high-salinity conditions of reclaimed coastal land.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.46-58
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• 2017

This study was conducted to investigate the optimal conditions for spore germination, prothallus propagation, sporophyte formation and seedling growth in Microlepia strigosa (Thunb.) C. Presl. Spore germination and prothallus development were promoted by low concentrations of Knop medium nutrient solution. The optimal medium for prothallus propagation and antheridium formation was 2X MS medium with 3% sucrose. The activated charcoal content of the medium did not affect prothallus proliferation. Among the various combinations of culture soil (bedding soil, peat moss, perlite and decomposed granite), a mixture of bedding soil, peat moss and decomposed granite at a ratio of 1 : 1 : 1 (v : v : v) had a positive effect on sporophyte formation. The most efficient conditions for promoting the growth of whole plants (sporophyte seedlings) were 50 - cell plug trays filled with a mixture of bedding soil and decomposed granite at a 2 : 1 (v : v) ratio.

• The Korean Journal of Food & Health Convergence
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• v.6 no.1
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• pp.9-15
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• 2020

Salinity with sodic condition disturbs germination, retards emergence, and slow down seedling development of Lemon Grass (Cymbopogon citratus).Lemongrass is a perennial grass plant widely distributed worldwide and most especially in tropical and subtropical countries. This research experiment was designed to evaluate the influences of (4 dSm^-1+ 13.5 (mmol L^-1)^-1/2, 5 dSm^-1+ 25 (mmol L^-1)^1/2, 5 dSm^-1+ 30 (mmol L^-1)^1/2, 10 dSm^-1+ 25 (mmol L^-1)^1/2 and 10 dSm^-1+ 30 (mmol L^-1)^1/2) on biomass produce of lemon grass against salt tolerance. The uppermost biomass yield (45.53 gpot^-1) was produced by 4 dSm^-1+ 13.5 (mmol L^-1)^1/2 treatment. The increase in the intensity of salts reduced the growth of lemon grass. Lower biomass yield (79.33 gpot^-1) was gained at 10 dSm^-1+ 30 (mmol L^-1)^1/2. 5 dSm^-1+ 25 (mmol L^-1)^1/2 treatment performed enhanced outcome i.e. the least reduction % over control (5.87). Salinity- sodicity showed serious effect on the growth reduction from 5.87% to33.60%. This reduction gap was affected by the negative effect of salinity and sodicity on Linseed growth. Salinity- sodicity showed severe impact on the growth reduction from 5.87% to33.60%. Based on the findings, lemon Grass (Cymbopogon citratus).was capable to grow up the maximum at 4 dSm^-1+ 13.5 (mmol L^-1)^1/2 treatment.

• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.511-515
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• 2013

Hypocotyls explants of melon seedling were cultured on Murashige and Skoog's (MS) medium supplemented with 1 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 mg/L benzyl aminopurine (BA) for 6 weeks to produce somatic embryos. In somatic embryos produced through intervening bright yellow friable (BYF) from the explants, somatic embryos with two-cotyledon (26%) and horn-type cotyledon (74%) were observed. The procambial strand of cotyledons was originated from circular procambial tissues of lower hypocotyls. The circular procambial independently divided into two procambial strand at the edge of cotyledonary-node, and then connected to each cotyledon to form somatic embryos with two-cotyledon. When cotyledon was horn-type, the circular procambial strand in lower hypocotyls would continuously remain connected to the cotyledon. However, somatic embryos with two or horn type cotyledon formed an abnormal shoot apex without the tunica-corpus structure or dome shape in the inter-cotyledonary area. These results demonstrated that the variation of cotyledon in somatic embryos was closely related to procambial tissue differentiation and shoot apical formation.

• Molecules and Cells
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• v.20 no.3
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• pp.416-422
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• 2005

We previously used Southern blot analysis to detect restriction-length polymorphisms between male fertile and cytoplasmic male sterile (CMS) cytoplasms at the coxII and atp6 loci of the mtDNA of Capsicum annuum L. Two copies of atp6 were found in each male fertile and CMS pepper lines. Interestingly, one of the copies of atp6 in CMS pepper was a 3'-truncated pseudogene. The open reading frame of the coxII gene was the same in the fertile (N-) and CMS (S-) lines. However, the nucleotide sequence in the S-cytoplasm diverged from that in the N-cytoplasm 41 bp downstream of the stop codon. To develop CMS-specific sequence-characterized amplified region (SCAR) markers, inverse PCR was performed to characterize the nucleotide sequences of the 5' and 3' flanking regions of mitochondrial atp6 and coxII from the cytoplasms of male fertile (N-) and CMS (S-) pepper plants. Based on these data, two CMS-specific SCAR markers, 607 and 708 bp long, were developed to distinguish N-cytoplasm from S-cytoplasm by PCR. The CMS-specific PCR bands were verified for 20 cultivars containing either N- or S-cytoplasm. PCR amplification of CMS-specific mitochondrial nucleotide sequences will allow quick and reliable identification of the cytoplasmic types of individual plants at the seedling stage, and assessment of the purity of $F_1$ seed lots. The strategy used in this report for identifying CMS-specific markers could be adopted for many other crops where CMS is used for F1 seed production.

• 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.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.191-211
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• 1987

Common usage of the concept of juvenility implies that there is one physiological phase, the juvenile phase, which manifests itself in the various morphological and physiological phenomena observed in juvenile higher plants. The juvenile phase is often defined as that time from seed germination until the plant attains the ability to flower regulating such behaviour. This definition precludes plants from flowering in the juvenile phase. It is of major interest, therefore, to identify the physiological controls(Bluehreife) regulating such behavior. The length of the juvenile period in higher plants ranges from one year to over 60 years in different species. The long juvenile period of seedling is the main cause of the long duration of the breeding process. I determined the length of the juvenile period in various plants and its control of phase changes in natural system in relation to factors such as plant size and age, shoot morphology, apex size, root system and phytohormonal and nutritional status is reviewed. From the own experimental and observational evidence available it appears that both hormonal and nutritional factors can be involved in control of juvenility but that a specific juvenile or flowering hormone is not involved. Grafting, ringing, scoring, root pruning and fertilization have been used to accelerate flowering, but in most cases these cultured treatments are only successful on plants that were passed the juvenile phase. It is suggested that there are intrinsic difference between the meristematic cells of the apieces of juvenile and adult shoot, which are thus determined with respect to there development potentialities. The problems associated with the maintenance of the determined state through mitosis are discussed. The properties of transitional forms of Ribes nigrum L. intermediate between the juvenile and adult phase, are descrived and there implications discussed. Analogies are drawn between juvenile phenomena in woody perennials and in herbaceous species.

• Korean journal of applied entomology
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• v.23 no.2 s.59
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• pp.126-131
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• 1984

Twenty one fungi were detected from 26 rice seed samples obtained from Yeongnam Crop Experiment Station, Honam Crop Experiment Station, Chungnam Provincial Office of Rural Development and farmers of Chungnam Province. Gerlachia oryzae was one of frequently detected fungi with $1.0\~45.0\%$ of detection ratio from 22 rice seed samples. The deep-freezing method was selected as the most suitable for routine seed health testing when the blotter method, deep-freezing method and agar plate method were evaluated for efficiency of detecting seed-borne G. oryzae from rice seeds. Our data obtained by seed component plating technique suggested that G. oryzae was present not only on chaff, in endosperm and in seed coat, but also in the embryo. Seed-borne G. oryzae caused seed rot, seedling blight and symptom of brownish discoloration on coleoptile primary and 2nd leaf when the infected seeds were sown in agar of test tube or in soil.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.20-29
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• 2000

This study was carried out to investigate the effects of shading on the growth of 1 -year-old seedlings of Cornus controversa. The height growth was highest in relative light intensities of 100% and 50%, but relative growth rate in 50% was higher than that in 100% treatment. The growth did not occur under 9% relative light intensity. The root collar diameter growth at different light intensities is similar to height growth. The leaf area was highest in 50% relative light intensity, and the leaf area under the light intensity was small compared with the control. SLA and LAI of seedlings increased with decreasing relative light intensity. The LAR and LWR of seedlings increased with decreasing light intensity, but LWR decreased at 9% relative light intensity. The dry weight of root, stem, leaf and branch, and the number of branch and leaf decreased with decreasing relative light intensity. T/R ratio was highest in 17% and 30% relative light intensity. Lateral root growth decreased with decreasing light intensity except for that in 50% light intensity.