• Research in Plant Disease
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• v.20 no.2
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• pp.79-86
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• 2014

In order to seek more eco-friend, economic and safer quarantine method than current methyl bromide fumigation, the convergent treatment with 200 Gy of gamma irradiation and several chemicals such as nano-siver particles (NSS), sodium dichloroisocyanurate (NaDCC) was tried on the cuttings of lily in the packing of catonnage box for export. With 6 independent experiments of gamma irradiation on the three lily cultivars, cvs. Siberia, Le reve and Sorbonne, incidence and severity of lily leaf blight was investigated on leaves and petals at 8-d after infection. 200 Gy of gamma irradiation decreased at 13-25% of severity on the leaf of Sorbonne, but it increased at 2-5% of severity on the leaf of Siberia and Le reve. Chemical substitutes such as NSS and NaDCC were not effective to control of lily blight on cuttings. By 200 Gy of gamma irradiation treatment, chlorophyll contents were statistically significantly decreased at 12-d after irradiation and the longevities vaselife of fully open flower of Siberia and Sorbonne were increased at 0.4 to 1.2 days. In addition, the relative fresh weights of the gamma irradiated cuttings were severely dried compared to the non-irradiated control. On the other hands, the symptoms of phyto-toxicity of high dose gamma irradiation at 1 or 2 kGy on cv. Siberia were to be blight at the tip of bloom, bent necks of flower, and delayed the process of flowering.

• Research in Plant Disease
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• v.22 no.4
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• pp.217-226
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• 2016

Seasonal prevalence of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) was investigated at a naturally infected orchard in Boseong, Jeonnam in 2014 and 2015. Stem canker began to occur in mid-February in 2014 and early March in 2015. Bacterial ooze was observed on canes, leaders and trunks until late May and gradually disappeared thereafter. The percentages of infected trees were 44.7% and 69.7% in 2014 and 2015, respectively. Trees with trunk canker in a previous year died in 2015. Leaf canker symptoms began to appear as brown spots with chlorotic halos in early May and irregular dark brown spots without halos were observed under humid conditions. Leaf canker progressed until mid-July in 2014 and late July in 2015. No Psa was detected from the leaf lesions on leaves thereafter, but new infection of Psa was observed on leaves in late October. Infected blossoms with blighted calyx were sometimes observed from mid-May. Optimal monitoring period to detect Psa was May when it could be easily detected from stems, leaves and blossoms. Disease cycle of bacterial canker of kiwifruit modified for Korea was proposed based on the seasonal prevalence of bacterial canker analyzed according to weather data in Boseong, Jeonnam over 2 years.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.85-93
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• 1984

This research was carried out to study the seed dormancy of radishes which were used for summer vegetation. The differences of dormancy of cultivars, maternal effects, the effect of full day length to mother plants, and the effects of chemical treatments for breaking the seed dormancy were considered for this study. These results sere summarized as follows; 1. The germination percentage of 7 cultlvars sown just after harvest were as follows;SP70-:0, PS11-:37.5, GJ75-:75.5, JD127-:77.5, YH85-:81.0, M55-:96.5, and JC73-:98.0%. 2. The dormany of $F_1$ seed of radish was severe when SP70-was used for mother plant. 3. Germination behavior was different by the maturity of plants grown for seed production. The dormancy of seed harvested from immature field-grown plants sown Nov. 10 was deeper than mature plants sown Mar. 22. 4. The germination ratio of tire seed of SP70-radish was increased by treatment of full day length to tire mother plant during full period of growing or since first flowering stage, while that was 0% by treatment since yellow ripening stage. 5. GA 200 ppm+thiourea 0.2% treatment was most effective for breaking of radish seed dormancy.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.77-84
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• 1984

This experiment was carried out to determine the effects of night temperature and amount of fertilization on growth and photosynthesis of red pepper plants for providing some basic imformation needed in improving the productivity of red pepper. 1. Plant height, stem length, number of flower buds, dry weight of plants and photosynthetic rate were higher in King Gun Gochu than in Dohusa, but number of leaves, number of internodes and leaf area we re higher in Dohusa compared to King Gun Gochu. 2. Plant height, number of leaves, number of flower buds, dry weight of plants, leaf area and photosynthetic rate were significantly increased by 50% increased fertilization compared to normal fertilization. 3. High night temperature($25^{\circ}C$) treatment increased plant height, stem length, number of leaves, number of internodes, number of flower buds, dry weight of plants and leaf area. 4. RGR and LAR were increased by 50% increased fertilization and high night temperature but NAR was decreased by high flower buds 5. Photosynthetic rate of King Gun Gochu was increased by 50% increased fertilization and high light intensity. 6. Number of flower buds was increased at King Gun Gochu by 50% increased fertilization and high night temperature ($25^{\circ}C$).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.12-18
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• 2005

This study was carried out to evaluate anthocyanine contents, effective components and major botanical characteristics of the new developed colored rices. Characteristics of colored rice lines showed variation in culm length and spikelets per panicle in CNU39, panicle length in CNU43, 1,000 grain weight in CNU90, and yield per plant in CNU119 were highly compared to the Check, Heugjinjubyeo. Relative optical density(ROD) of Heugjinjubyeo was the highest at 530 nm, followed by CNU71, CNU73 and CNU119. The high peaks of ROD of Heugjinjubyeo and CNU71 appeared at 280 nm and 530 nm, and that of CNU43 appeared at 430 nm. The relative anthocyanin contents (RAC) per plant of the CU 71 among the new developed rice compared by yield per unit area was very high, fellowed by CNU73 and Heugjinjubyo.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.220-223
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• 2012

A new cultivar $Dendranthema$ $grandiflourm$ 'Dream Water' was developed at Gyeonggi-do Agricultural Research & Extension Services, Korea in 2009. The cultivar 'Dream Water' was initially derived from the cross in 2005 between 'Patra', a spray chrysanthemum cultivar with yellow single type, and 'Ruces', a spray chrysanthemum cultivar with white single type. The cultivar has single type with ivory petals. Trial evaluation was conducted from 2006 to 2009 for selection of this variety, including a shading culture in spring and a retarding culture in summer. The flowering time of 'Dream Water' was October 24th, and year-round flowering is possible by shading or lighting treatment. The diameter of the flower is 56.0 mm. Number of flowers per stem and petals per flower are 11.1 and 26.8, respectively. Its leaf color was green (Green Group 147A) and plant height was 89.7 cm. Days to flowering under the short day treatment is about 54 in spring, and diameter of flower center was 1.4 cm in the summer. The vase life was 16.7 days in autumn and consumer's preference of new spray chrysanthemum is high level than control.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.517-521
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• 2013

A new cultivar Dendranthema grandiflourm 'Dream Round' was developed at Gyeonggi-do Agricultural Research & Extension Services (GARES), Korea in 2010. The variety 'Dream Round' was initially derived from a cross in 2006 between 'Hebo' a seed parent, a spray chrysanthemum cultivar with white anemone type, and 'Samos' as a pollen parent, a spray chrysanthemum variety with white anemone type. The cultivar has anemone type with white petals. Trial evaluation was conducted from 2008 to 2010 for the selection of that cultivar, including a shading culture in spring and a retarding culture in summer. The flowering time of 'Dream Round' was October 24th, and year-round flowering was possible by shading or lighting treatment. The diameter of flower of 'Dream Round' was 34.1 mm. Numbers of flowers per stem and petals per flower of 'Dream Round' were 12.8 and 26.1, respectively. Its leaf color was green (Green Group 147A) and plant height was 92.4 cm. Days to flowering of 'Dream Round' under the short day treatment was about 54 in spring, and diameter of flower of 'Dream Round' was 34.2 mm in the summer. The vase life of 'Dream Round' was 21.7 days in autumn.

• Research in Plant Disease
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• v.26 no.1
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• pp.29-37
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• 2020

Stem blight symptom of soybean was severely developed in 2016 in Hwaseong and Yeoncheon. During the seedling period, the damping-off of seedlings and the brown or black spots of cotyledons were observed. After August, the leaves began to be yellowed, and partially browned areas on leaves began to develop. After September, microsclerotia began to form even on the surface of the stems that had exhibited water-soaking symptom. After mid-October of the harvest season, the epidermis of the stem was peeled off, resulting in the formation of a large number of microsclerotia in the cortex. The pathogens isolated from these symptoms were the best in mycelial growth at 32-35℃, and the formation of microsclerotia was the most at 20-28℃. The pathogen was identified as Macrophomina phaseolina through the morphological characteristics of the pathogen and the sequencing of the internal transcribed spacer region gene. In addition, when inoculated with a soybean stem using toothpicks cultured with the pathogen, the same symptoms as seen on the soybean field occurred. When the pathogen was re-isolated at the lesion site, the same pathogen was isolated and identified as Macrophomina phaseolina. Based on the results, the disease is reported as soybean charcoal rot.

• Korean Journal of Soil Science and Fertilizer
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• v.4 no.2
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• pp.143-147
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• 1971

Field experiments were carried out to determine the effect of B on rape with application of lime and compost in sandy upland soil and in clayey paddy soil. The plant samples from each treatment at flowering stage were analyzed to interpret the yield response. The effect of B was very significant in both soils, but more marked in sandy upland soil. The application of 20kg/ha borax appears to increase upto the possible level that can be achieved by B application. Application of 40kg/ha borax did not give any further additional response. In acidic paddy soil (pH 5.4), the effect of B was fully exhibited only with liming. Liming neither intensified the B deficiency nor reduced the B content in the plant tissue, but rather promoted the growth of rape plant. There was highly significant negative correlation between Ca/B ratio and seed yield ($r=-0.74^{**}$), but it was very difficult to draw a line between normal and deficient Ca/B ratio. It is very interesting that boron application significantly increased the Ca uptake in no lime treatment. Application of compost was generally inffective and did not affect the B supply to the plant. However, it appears to increase K uptake slightly and give a little favorable effect on growth of plant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.5 no.1
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• pp.19-24
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• 1976

A determination of proper maturity is a significant factor for a good quality and storage. This study is aimed at a determination of optimum harvest date related to a decisive measuring of maturity in Spur Golden Delicious. In this case, respiratory status and other characteristics are taken as a indicator for maturing determination. The results are as follows. 1. Respiratory rate has been decreased through a fruit development and come to its minimized point on Sep. 25. at last. On the contrary its tendency has been increased after Sep. 25. It is also estimated that the former is pre-climacteric, the latter climacteric rise based on dimacteric minimum Sep. 25. 2. A flesh hardness has maintained comparably high value until Sep. 18. But in the point of climacteric minimum, Sep. 25, curve of flesh firmness has rapidly been broken down, and after Sep. 25, tendency has slowly decreased at the sucessive date. 3. Pectin content, optimum acidity are remarkably decreased after Sep. 25, Oct. 2 respectively. 4. When water soluble sugar content shows to be swung from climacteric minimum, any resonable tendency are not found. 5. In this experiment, optimum harvest time is found by Oct. 2, in time of 145 days after flowering.