• Korean Journal of Plant Resources
• /
• v.13 no.1
• /
• pp.41-47
• /
• 2000

This study was conducted to evaluate development of seed pellet technique such as pellet polymer search, the shape formation and hardness, the germination and emergence rate of the pellet seeds for labor-saving and reducing production cost in onion(Allium cepa L.) cultivation. The pellet seeds shape formation was good such as kaolin, clay, ash, and gypsum, and clay was good shape formation but surface of pellet seed was cracked during the drying. PG(pearlite + gypsum) as pellet material and PVA as binder were the best among the material in consideration with shape and hardness together. The hardness of the pellet seeds was affected by polymers, the kinds and concentration of binders, and that degree was large at polymer. The high hardness polymers were gypsum and coal ash, but burned lime was the lowest hardness among the pellet material. The germination(GP) and emergence percentage(EP) of pellet seed with PG in vitro were the highest among the material, and that was 93.6, 91.8%, respectively. The EP of pellet seed with PG at 20, $25^{\circ}C$ were 91.3, 92.0%, respectively, The EP of pellet seed were over the 91%, and those did not show difference with field moisture capacity , and that of 5 and 6mm size seed were the highest as 92%, respectively. and other size seeds showed over 90%, too. The EP of pellet seed with PG was decreasing as increasing the sowing depth, and that of at 10mm sowing depth was the highest as 92.7%. The time to 50% emergence of that under 70% field moisture capacity was 158h, and that was delayed at 20h compare to control seed.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2021.04a
• /
• pp.24-24
• /
• 2021

The Cassava (Manihot esculenta Crantz) is one of the major food crops in the tropical or subtropical regions. Recently, clean planting materials of improved cassava cultivars are in high demand. Problems in the propagation of cassava are virus vulnerable and low rates of seed germination. Thus, the study was undertaken to develop an efficient in vitro mass propagation protocol of Manihot esculenta Crantz. So we tried to optimize protocols for mass production from axillary buds of Cassava. Young and actively growing stem segments were excised from adult plants of cassava. Samples were cut into a 3~4 cm nodal segments with axillary buds, and cultivated in the different medium supplemented with various plant growth regulators for 4 weeks. For shoot multiplication, axillary buds approximately 1 cm in length were taken from in vitro derived shoots and subcultured. After 4~6 weeks, the shoot generation rate showed 55.6%. The shoot number and its length was 1.0/explant and 2.3 cm in the most favorable medium composition. The auxin β-indolebutyric acid(IBA) 0~2.0 mg/L was proved to be effective on root development. Plantlets with fibrous roots easily generated tuberous roots in vitro. The tuberous roots were induced only when both kinetin and IBA were used in combination. after 8 weeks, the root generation rate showed 100%. The root number and its length was 17.2/explant and 2.2 cm in the most promising medium composition. Our experiments confirmed that in vitro growth and multiplication of plantlets could depend on its reaction to the different medium composition, and this micropropagation techniques could be a useful system for healthy and vigorous plant production.

• Journal of Microbiology and Biotechnology
• /
• v.7 no.1
• /
• pp.13-20
• /
• 1997

Plant growth-promoting Psudomonas fluorescens GL20 was isolated from a ginseng rhizosphere on chrome azurol Sagar. P. fluorescens GL20 produced a large amount of hydoxamate siderophore in an iron-deficient medium. The siderophore showed significantly high specific activity of 20.2 unit. Using an in vitro antifungal test, P. fluorescens GL20 considerably suppressed growth of phytopathogenic fungus Fusarium solani, inhibiting spore germination and germ tube elongation. In pot trials of kidney beans with P. fluorescens GL20, disease incidence was remarkably reduced up to $68{\%}$ compared with that of F. solani alone, and plant growth was also increased nearly 1.6 fold as compared to that of the untreated control, promoting elongation and development of the roots. These results indicate that the plant growth-promoting activity of P. fluorescens GL20 can play an important role in biological control of soil-borne plant disease in a rhizosphere, enhancing the growth of plants.

• Plant Resources
• /
• v.7 no.3
• /
• pp.222-225
• /
• 2004

In Japan, propagation of cyclamen is mainly from seedlings. However, seeds are expensive and germination is slow and non..uniform. Therefore, to achieve genetically uniform propagation, multiplication must be vegetative. The rooted tuberous stems without shoots as sources of explants were cultured on the media containing BA and sucrose. After 30 days cultivation, tuberous roots were produced from the root ends attached to a tuberous stem and its capability was dependent on the type of media. The highest percentage of tuberous root formation was observed in Culture on the medium of 1/3 MS containing 0.05mgL$^{-1}$ NAA, 0.5mg L$^{-1}$ BA and 5% sucrose. Growth rates of the tuberous roots were greatly influenced by the cutting positions of a root in explants. The highest growth of was observed if small amount of root end was cut at initiation of tissue culture.

• Korean Journal Plant Pathology
• /
• v.1 no.1
• /
• pp.28-32
• /
• 1985

The experiments were carried out to investigate a practical method for controlling wilt of strawberry by fungicides in vitro and in field. Captafol and benomyl were the most effective in inhibiting chlamydos-pore germination and mycelial growth of the fungi. In field tests, captafol, benomyl and thiophanate-methyl showed some control effect against the disease. The propagule number of F. oxysporum f. sp. fragariae in soil was greatly reduced by soil drenches of captabol, whereas that of Trichoderma sp. was increased.

• Mycobiology
• /
• v.35 no.2
• /
• pp.87-90
• /
• 2007

A total of 520 overwintered sclerotia were collected from surface of soil under mulberry trees in six locations in Korea during February in 2006 and 2007. The collected sclerotia were tested for their germination in vitro and identified based on their morphological characteristics. Out of all sclerotia tested, 52.3% of the sclerotia germinated and produced two types of apothecia. The two types of fungi occurred from the sclerotia at the ratio of 49.8 vs. 50.2. The fungal type with cup-shaped apothecia was identified as Ciboria shiraiana and another type of fungus with club-shaped apothecia as Scleromitrula shiraiana. Taxonomy and distribution of the two sclerotial fungi were described and discussed.

• Journal of Korean Society of Forest Science
• /
• v.100 no.2
• /
• pp.172-177
• /
• 2011

This study was conducted to establish the optimal condition for in vitro propagation of wild Cynanchum wilfordii. The highest in vitro seed germination rate of 91.6% was obtained from the seed treated with gibberellic acid ($GA_{3}$) (100 ppm) for 24 hours followed by cultured on Woody Plant Medium (WPM) media supplemented with 1.0 mg/L 6-benzyl adenine (BA). The best shoot height obtained (5.2 cm) in medium with 1.0 mg/L $GA_{3}$, but the plants was grown abnormally and eventually died. The highest number (2.4) was shown when shoot were in cultured on the media including 0.1 mg/L BA after 4 weeks. Root induction from shoot obtained in vitro culture was effective on ventilation and without plant growth regulators (PGRs) and root length was highly developed (2 cm) at 0.1 mg/L naphthalene acetic acid (NAA). The highest survival rate (70%) was when plantlet grew pre-ventilation of in vitro condition.

• Journal of Ginseng Research
• /
• v.13 no.1
• /
• pp.114-118
• /
• 1989

Tolclofos-methyl applied as seed dipping at 1,000 ppm for 3 hrs before sowing and soil drenching at the rate of 300 g ai./10 a in the middle of April protected emerging seedlings of Panax ginseng from damping-off caused by Rhiiutonia solani(AG2-1) in Yangjik Soil artificially infested with the pathogen. Germination rates with tolclofos-methyl, pencycuron, and control were 53.7%, 45.8%, and 7.5%, respectively, while the rate of the seeds at non-infested soil was 62.6%. The effectiveness of Tolclofos-methyl against the pathogen in the soil lasted upto 32 days in vitro. However, the transpiratio of ginseng seedlings increased greatly with chemical treatment, showing 0.02, 0.12, and 0.24 m1/cm2 leaf area/day at 0, 1,2, and 4 ppm a.i. of the fungicide, respectively.

• Microbiology and Biotechnology Letters
• /
• v.23 no.4
• /
• pp.378-383
• /
• 1995

Antifungal activity of caproic acid against Botrytis cinerea was investigated in this research. In vitro 200 ppm of caproic acid was inhibited on the germination and the mycelium growth of B. cinerea. 250 ppm of caproic acid showed the fungicidal activity against sensitive B. cinerea. To compared the inhibitory effect of treatments against B. cinerea, the field essay was carried out in the grape vineyard. The rot (%) of control, 3000 ppm of caproic acid, 3000 ppm of sodium caproate, and sumisclex were 30.7%, 10.2%, 22.8%, and 3.1%, respectively. The anti-Botrytis efficiency (%) was also evaluated as follows; 3000 ppm of caproic acid 66.8%, 3000 ppm of sodium caproate 25.7%, and sumisclex 89.9%. The efficiency between sumisclex and 3000 ppm of caproic acid was no significant difference at the 1% level by Tukey test. These results suggest that 3000 ppm of caproic acid may be greater than that of sodium caproate.

• BMB Reports
• /
• v.38 no.1
• /
• pp.82-88
• /
• 2005

Bacillus cereus 28-9 is a chitinolytic bacterium isolated from lily plant in Taiwan. This bacterium exhibited biocontrol potential on Botrytis leaf blight of lily as demonstrated by a detached leaf assay and dual culture assay. At least two chitinases (ChiCW and ChiCH) were excreted by B. cereus 28-9. The ChiCW-encoding gene was cloned and moderately expressed in Escherichia coli DH5$\alpha$. Near homogenous ChiCW was obtained from the periplasmic fraction of E. coli cells harboring chiCW by a purification procedure. An in vitro assay showed that the purified ChiCW had inhibitory activity on conidial germination of Botrytis elliptica, a major fungal pathogen of lily leaf blight.