• Korean Journal of Plant Tissue Culture
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• v.22 no.6
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• pp.311-316
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• 1995

In an attempt to obtain intersubgeneric somatic hybrids of Pelargonium aridum and P.zonale, protoplast isolated from the two species were fused by using polyethylene glycol(PEG) and electorfusion methods. Protoplast were isolated from cotyledon and leaf tissues using MS medium containing 550 mM sucrose, 0.7% cellulase (Onozuka R-10) and 0.4% Macerozyme. The optimum number of protoplasts per mL of culture medium was 6 x 10$^4$. Protoplast fused by the electrofusion method were more active than by PEG method. Heterokaryotically fused protoplasts formed calli when cultured in MS medium containing 550 mM glucose, 1 to 2 mg/L NAA and 0.5 to 1 mg/L BA.

• Journal of Practical Agriculture & Fisheries Research
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• v.12 no.1
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• pp.47-52
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• 2010

Squash cultivars of Cucurbita moschata have good fresh quality, but their viny growth habit hinders wide cultivation under structure. On the other hand, 'Zucchini' varieties of C. pepo have bush growth habit and better growth ability under the low temperature condition than C. moschata, but have inferior flesh quality. To combine desirable characteristics of the two species, many attempts have been exerted to obtain interspecific hybrids. A shootless phenomenon was found among segregating populations; the cotyledon expanded normally but further shoot growth. The inheritance of the character was investigated in F₂ and BC₁F₂ populations. The segregation ratios indicated that the shoot-lacking characteristics is expressed by double recessive gene pairs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.152-155
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• 2003

Burcucumber (Sicyos angulatus L.), used as a medicinal or rootstock for cucurbitaceous crops have shown high variation in seed maturity and size. This study was carried out to determine the effect of seed maturity and size on seed germination, seedling emergence and growth of burcucumber, Seeds collected from a native site were divided into small, medium and large ones after sorted to mature and immature ones. Their germination, seedling emergence and growth were done in indoor and a green house. Mature seeds showed higher germination and seedling emergence rate than immature ones. Regardless of their maturity, medium. and small seeds showed higher germination rate than large ones. Medium and large seeds, however, had the greatest and the least seedling emergence, respectively. Seedling height, number of true leaves areas of cotyledons and true leaves except hypocotyl length were increased with increased seed size although were not affected by the maturity. Cotyledon, leaf, hypocotyl, root and their total dry weights were greater in large mature seeds than large immature ones while increased with increased seed size in both maturities.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.310-316
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• 1997

This experiments comparisons were conducted to establish the effective sap analytical method including quantitative analysis of nitrate and phosphorous, sap extraction method, extraction rate, macerating time and sampling position. Earl's Favorite muskmelon was sown on February 11th, 1993 and transplanted to rockwool slab when three to fourth true leaf appeared. Non-circulating system was employed in this experiment. Sap testing using a sample provides an immediate analysis of nutritional status of the crop and potential problems can be recognized and corrective measures taken. Some methods were recommended UV-spectroscopy for the analysis of nitrate nitrogen, Vanad molybdenium acid method for phosphorous. Optimal extraction rate of sample to water was determined as one to four and the best result observed at 60seconds in macerating duration. Further trials would be requested about sampling time due to the difference according to the sampling time. Given sampling position was favorable for the sap analysis.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.291-297
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• 1994

Seedlings of eight varieties of tomato were treated on the soil surface by each six application rate (0 to 5g ai/ha) of herbicide quinclorac. Percent of control in plant height at 7 days after treatment ranged from 69% to 81% at 5g ai/ha application of quinclorac. At 28 days after treatment those of (2-26)*836038 and (TR*VC8-1)-1-2F4 were 88% and 89%, respectively. However, those of other six varieties except former two varieties were 61% to 68%. The variations of percent of control in shoot dry weight among eight varieties were larger than those in plant height. Those of (2-26)*836038 and (TR*VC8-1)-1-2F4 were also higher than those of other six varieties at 4 - 5g ai/ha application of quinclorac.

• Research in Plant Disease
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• v.10 no.1
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• pp.78-81
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• 2004

The resistance of 10 varieties of cucumber (Cucumis sativus L.) to powdery mildew, caused by Sphaerotheca fusca, was evaluated by a leaf disk assay. Leaf disks (10 mm in diameter) were removed from fully expanded leaves and then placed in petri dishes containing 0.16％ water agar amended with benzimidazole. Leaf disks were inoculated by dropping a 10 $\mu$l of conidia suspension. Conidiophore formation of powdery mildew was the greatest at $25^{\circ}C$. The response of the host to powdery mildew, based on the inoculation onto disks of the first leaf, highly correlated with results obtained from harvesting stage of cucumber plants in greenhouse test (r = 0.99$^{**}$). It is indicating that a leaf disk assay may precisely predict the response of cucumber plant to S. fusca.a.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.186-190
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• 1984

Photosynthetic rate of sesame varieties was investigated under the different cultural environments such as planting density or light intensity. The photosynthetic rate of Pungnyeon, monoculm variety, was higher than that of Kwangsan before flowering stage, while it was vice versa after the flowering stage. The maximum rate of photosynthetic rate was obtained three weeks after planting. The effects of light intensity on photosynthetic rate four weeks after planting was not apparent when the light intensity was reduced to the level of 35% and 55%, respectively. However, when the light intensity was reduced to 75% of the normal light intensity, the photosynthetic rate was also greatly reduced. The Photosynthetic rate after the flowering stage was reduced in the order of normal light, 35% and 75%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.411-414
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• 2005

The purpose of this study was to determine proper method for alternative row culture of two varieties to increase seed yield in soybean. The test varieties 'Hwangkeumkong' and 'Taekwangkong' which were planted monoculture of each variety, seeding after mixing same number of seeds of two varieties, 1-row alternation, 2­row alternation, 2-row 'Hwangkeumkong' and 1-row 'Taekwangkong' and 1-row 'Hwangkeumkong' and 2­row 'Taekwangkong'. Alternative planting of 1-row 'Hwangkeumkong' and 1-row 'Taekwangkong' resulted the highest canopy height and reduced lodging most effectively. The terminal and the 9th leaves of 'Taekwangkong' in alternative variety planting showed the higher photosynthetic ability than pure stand of that. Alternative planting of two varieties in every other row increased yield by $17\%$ in 'Hwangkeumkong' and by $8\%$ in 'Taekwangkong'.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.235-238
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• 1989

This study was carried out to investigate the effect of environmental conditions of air temperature and relative humidity, varieties, and water content of leaves at harvesting time on the occurrence of barn rot during curing of burley tobacco. The curing environmental condition was combined with 4 air temperatures ranging from 25$^{\circ}C$ to 40$^{\circ}C$ and 3 different relative humidities. The harvested leaves with 3 different water contents were cured during the rainy season in curing barn. Barn rot occurred the most at 30$^{\circ}C$, and reduced at 25$^{\circ}C$ and remarkably decreased at above 35$^{\circ}C$. But no barn rot was observed at 40$^{\circ}C$. In influence of relative humidity, the percentage of rotten leaves was highest at 100% RH and remarkably reduced at lower RH. Among two varieties, KB 101 was rotted smaller than Burley 21 under the all temperature and relative humidity conditions, however those considerably showed no difference. The rate of disease development increased in the lower leaves more than in the upper leaves. In the water content of leaves at harvesting time, 29.5% of the rotten leaves was observed at W.S.D. (water saturation deficit) 10.3%, but no barn rot was found at W.S.D. 6.4%.

• Korean Journal of Medicinal Crop Science
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• v.7 no.1
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• pp.22-26
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• 1999

This study was investigated to elucidate the growth characteristics of Acanthopanax sessiliflorus grown under different conditions and seasons. The emergence percent of seeds sown in the vinyl house was about 2.2 times better than that in the open field. The plants which had 2 to 3 normal leaves showed the highest value in root setting percent, and the root setting percent was decreased significantly in plants with one normal leaf and 4 to 5 normal leaves. The root setting percent of plants transplanted from April 19 to May 2 was 100%, but plants transplanted at April 4 or from May 17 to June 1 showed lower root setting. Tree percent, plant height. root length and fresh weight of plants grown by transplanting culture were better than those of plants grown by direct seeding.