• The Korean Journal of Mycology
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• v.22 no.2
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• pp.172-183
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• 1994

The productions of arbuscular mycorrhizal fungal(AMF) spores were observed by adding three different commercial fertilizers on AMF inhabiting soils. Various morphological features, vesicles, arbuscles, sporulations of spore, and flower-like-structures, were also found in the mycorrhizal roots during 80 days after transplanting. Spore prodcutions of the employed AMF were observed to be periodically increased with the intervals of 40 days. Sorghum, green onion, hot pepper, and wild legume plants were appeared to be a good plant for productions of AMF and as the host of AMF. The productions of AMF spores was inversely related to phosphate fertilizer, and also observed to be low in the plant pots added with whole balanced fertilizers.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.339-344
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• 2012

This study was carried out to research microorganisms having the antifungal activity against ginseng Alternaria blight pathogen Alternaria panax and ginseng anthracnose pathogen Colletotrichum gloeosporioides. Eleven Bacillus strains. were isolated from Korean traditional soybean paste and Kimchi. Among the 11 isolates, DJ5, KC1, KC2 and KC4 showing antagonistic activity on the mycelial growth of A. panax and C. gloeosporioides in pairing culture were finally selected as the antagonistic microorganisms. Based on 16s rRNA sequence and phylogenetic tree analysis, they were identified as Bacillus spp.. The selected microorganisms were investigated antagonistic activity by measured leaf-segment colonization in pot test. When Bacillus sp. were injected after A. panax treatment, KC1, KC2 and KC4 showed similar effect to chemical pesticides treated control. To measure preventive effect of Bacillus sp, antagonistic microorganisms were injected and C. gloeosporioides was treated in pot. When measuring the effectiveness for the prevention of Anthracnose, All Bacillus spp. showed approximately 83~90 % degree of superior preventive effect. In general, The four Bacillus spp. isolated from Korean traditional fermented foods showed therapeutic effect of Alternaria blight and preventive effect of Anthracnose.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.101-105
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• 2003

This experiment was conducted to find out the effect of day length on the production of high quality plug seedlings in onion (Allium cepa L.). Two cultivars, ‘Changnyongdaego’ and‘Wolryun’, were grown to seedlings in 200-cell plug trays under 11.5, 12.5, 13.5 hours and natural day length. These seedlings were transplanted to the pot (16 cm In diameter) and grown under 16 hours day length. Number of leaves and neck diameter showed better growth in the longer than shorter day length treatments, but plant height old sheath length were retarded in the longer day length treatments. Growth such as no. of leaves, neck diameter, plant height and sheath length increased with the passage of day, but plant height and neck diameter decreased by treatment over 20 days with 13.5 hours day length. Bulbing and bulb size of onion after transplanting were enhanced in the seedlings cultured under longer day lengths. From the above results, treatment of long day length during seedling culture in plug tray can control the overgrowth and produce high quality plug seedlings.

• Applied Biological Chemistry
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• v.17 no.4
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• pp.235-239
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• 1974

Rice root activiators (phthalamic acid (PA) and p-chlorophenyl PA (PCPPA) were tested in pot culture for their effects on yield of IR667-Suwon 214 weak in root activity. The results were as follows: 1) Maximum percentage yield increase was 36.7% with organic matter applied and 13.3% without organic matter in 100 ppm (90ml/0.05$m^2$) of PCPPA treatment. 2) Root activators increased oxidizing power of root (root activity), consequently gave a balanced nutrient uptake, stimulated root growth and subsequent shoot growth. 3) Root activators increased number of panicle per hill, grain weight, filled grain ratio and effective tiller ratio.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.304-311
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• 2018

Background: Ginseng black spot disease resulting from Alternaria panax Whuetz is a common soil-borne disease, with an annual incidence rate higher than 20-30%. In this study, the bacterial strains with good antagonistic effect against A. panax are screened. Methods: A total of 285 bacterial strains isolated from ginseng rhizosphere soils were screened using the Kirby-Bauer disk diffusion method and the Oxford cup plate assay. We analyzed the antifungal spectrum of SZ-22 by confronting incubation. To evaluate the efficacy of biocontrol against ginseng black spot and for growth promotion by SZ-22, we performed pot experiments in a plastic greenhouse. Taxonomic position of SZ-22 was identified using morphology, physiological, and biochemical characteristics, 16S ribosomal DNA, and gyrB sequences. Results: SZ-22 (which was identified as Brevundimonas terrae) showed the strongest inhibition rate against A. panax, which showed 83.70% inhibition, and it also provided broad-spectrum antifungal effects. The inhibition efficacies of the SZ-22 bacterial suspension against ginseng black spot reached 82.47% inhibition, which is significantly higher than that of the 25% suspension concentrate azoxystrobin fungicide treatment (p < 0.05). Moreover, the SZ-22 bacterial suspension also caused ginseng plant growth promotion as well as root enhancement. Conclusion: Although the results of the outdoor pot-culture method were influenced by the pathogen inoculum density, the cropping history of the field site, and the weather conditions, B. terrae SZ-22 controlled ginseng black spot and promoted ginseng growth successfully. This study provides resource for the biocontrol of ginseng black spot.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.301-306
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• 2004

The present water quality standards for agricultural were established without considering the effects of water quality on the safety, growth, yield and quality of crops. This study was carried out to investigate the effects of irrigation water quality on the growth, yield, and grain quality of rice, and to acquire basic knowledges to set up water quality standards for irrigation. The field and pot experiments were conducted with irrigation water that was previously adjusted four concentrations (control, 5, 10, 20 mg/L) and six concentrations (control, 5, 10, 15, 20, 30 mg/L) by $NH_4NO_3$ solution and replicated three and four times with randomized block design, respectively. The results of this study showed that the inorganic nutrient of rice plant, rice protein contents and number of panicle tended to increase as the T-N concentration in irrigation water was increased. In addition, grain yield at T-N 10 mg/L and 20mg/L were significantly higher than the control at the field experiment. From the pot experiment at T-N 30 mg/L, the percentage of head rice was slightly lower due to the increase of green kernel and white belly/core kernel.

• Mycobiology
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• v.32 no.3
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• pp.139-147
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• 2004

A severe damping-off disease of bush okra caused by Pythium aphanidermatum, was diagnosed in plastic houses in Der Attia village, 15 km southwest of El-Minia city, Egypt, during the winter of 2001. Bush okra seedlings showed low emergence with bare patches inside the plastic houses. Seedlings that escaped pre-emergence damping-off showed poor growth, stunting and eventually collapsed. Examination of the infected tissues confirmed only Pythium aphanidermatum, showing its typical intercalary antheridia, and lobulate zoosporangia. P. aphanidermatum was shown to be pathogenic on bush okra under pot and field experiments. Bacteria making inhibition zones against the damping-off fungus P. aphanidermatum were selected. Agar discs from rhizosphere soil of bush okra containing colonies were transferred onto agar plate culture of P. aphanidermatum. After 2 days of incubation, colonies producing clear zones of non-Pythium growth were readily detected. The two bacteria with the largest inhibition zones were identified as Pseudomonas fluorescens. Bush okra emergence(%) in both pot and plastic houses experiments indicated that disease control could be obtained by applying P. fluorescens to the soil or coating the bacteria to the bush okra seeds before sowing. In the plastic houses, application of the bacteria onto Pythium-infested soil and sowing bush okra seeds dressed with bacteria gave 100% emergence. In addition, This was the first reported disease of bush okra by this oomycete in Egypt.

• Korean Journal of Plant Tissue Culture
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• v.28 no.4
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• pp.179-184
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• 2001

We evaluated a possibility of the use of chloroplast number per guard cell pairs as a measure for ploidy level in the different ploidy levels of tobacco plant (Nicotiana tabacum L. cv. BY-4) . The guard-cell chloroplast numbers of leaves of haploid plant were a half of wild-type plant. Furthermore, the number of chloroplast per guard cell pairs of the leaves of doubled-haploid plant increased in two times compared with that of haploid plant. In addition, the chloroplast number was not changed in the F$_1$ progenies. The change of the chloroplast number by leaf stage was not observed. The results indicate that there is a strong relationship between ploidy level (2x and 4x) and chloroplast number per guard cell pairs. This relationship was also, observed in both in vitro and pot cultured plants. It was determined that the measurement of chloroplast number in guard cells of leaf epidermis is simple to use and less labour intensive, and hence can be considered a practical alternative to the chromosome counting methods or flow cytometry in the tobacco plant.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.207-210
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• 2010

An Asiatic lily (Lilium spp.) cultivar 'Onnuri' for cut and pot flower was developed in 2006 at Jeollabukdo Agricultural Research & Extension Services, Iksan, Korea. The cross was made in 1999 between 'Avignon', orange colored, and 'Nove Cento', yellow colored. A line was preliminarily selected as 'A99-6-48' by reason of stable flower color and shape among germinated seedlings. It had been multiplicated through in vitro culture and then bulbed on field during 2002~2003. After characteristics were investigated from 2004 to 2005, finally it was named as an 'Onnuri' in 2006. Flower of 'Onnuri' belongs to orange-red group with its center shown orange group. Plant height is 92.8 cm, flower size is medium as 13.8 cm. Stigma color is red-brown and blooming direction is upward-facing. Flowering time is mid-June.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.44-44
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• 2019

This study aimed to develop a suitable method for inducing the proliferation of prothallus and producing sporophytes of rock polypody (Polypodium vulgare L.). The prothalli used in all experiments were obtained from spore germination and sub-cultured for 8-week intervals. The most appropriate media for prothallus propagation were investigated by culturing 300 mg of prothallus in MS ($1/4{\times}$, $1/2{\times}$, $1{\times}$, and $2{\times}$ strength) medium and in Knop medium for 8 weeks. Cultures were maintained at a temperature of $25{\pm}1^{\circ}C$, light intensity of $30{\pm}1.0{\mu}mol-m-2{\cdot}s-1$, and a photoperiod of 16/8 h (light/dark). Fresh weight of prothalli was 4.8 g on $1{\times}$ MS, 4.5 g on $1/2{\times}$ MS and 4.3 g on 1/4 MS medium. To select a suitable soil combination for sporophyte formation, 1.0 g of prothallus was ground with distilled water, spread in five combinations onto different soil substrates (decomposed granite, horticultural substrates, peat moss, and perlite), and then cultivated for 13 weeks. The sporophyte cultures were maintained at a temperature of $25{\pm}1^{\circ}C$, light intensity of $43{\pm}2.0{\mu}mol-m-2{\cdot}s-1$, humidity of $84{\pm}1.4%$, and a photoperiod of 16/8 h (light/dark). The results showed that a mixture containing a 2:1 (v:v) ratio of horticultural substrate and perlite, increased sporophyte formation to 462.5 sporophytes per pot (7.5 cm2). The other soil substrates produced from 314.5 to 405.3 sporophytes per pot. Therefore, our results will provide conditions suitable for mass production of Polypodium vulgare L.