• Korean Journal of Medicinal Crop Science
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• v.22 no.5
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• pp.391-397
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• 2014

To control the disease of root rot in ginseng nursery, inorganic sulfur solution of 0.1%, 1.0%, and 2.0% were irrigated by amount of $10{\ell}$ per $3.3m^2$ before sowing. On the last ten days of July, Fusarium solani and F. oxysporum were similarly detected by 44.8% and 43.8%, respectively, while Cylindrocarpon destructans was low detected by 4.4% in the diseased seedling. The more sulfur's concentration was increased, the more soil pH was decreased. Soil pH was decreased from 5.87 to 4.59 by the irrigation of sulfur solution of 1.0%. The more sulfur's concentration was increased, the more electrical conductivity (EC) of soil was increased. EC was increased from 0.27 dS/m to 1.28 dS/m by the irrigation of sulfur solution of 1.0%. Irrigation of sulfur solution was effective on the inhibition of damping-off caused by Rhizoctonia solani in ginseng seedling. Control value for damping-off by the irrigation of sulfur solution of 1.0% and 2.0% were 75.7%, and 78.5%, respectively. Growth of leaf was inhibited by the irrigation of sulfur solution of 2.0%. Root weight per $3.3m^2$ showed the peak in sulfur solution of 1.0%, while survived-root ratio and root weight per plant were decreased in the level of 2.0%. Survived-root ratio of seedling in sulfur solution of 1.0% was distinctly increased by 4.7 times compare to the control, but control value for root rot was relatively low as 49.2%. Mycelium growth of C. destructans, F. solani, and R. solani were distinctly inhibited by the increase of sulfur's concentration in vitro culture using PDA medium.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.151-156
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• 1988

A leaf anthracnose disease of pepper(Capsicum annuum L.) seedling caused by Colletotrichum coccodes was found in fields of Chungnam District for the first time in 1988. Initial symptom of the disease was spotting on leaves and stems of the seedlings. The spots became sunken and gradually increased in size and coalesced to form bigger irregular spots and blights on the leaves. In severely affected fields, many pepper seedlings were defoliated and lodged. Field survey revealed that the infection rate of anthracnose ranged form 15.3% to 92.3%. Conidia from lesions on seedlings were hyaline, aseptate, straight, cylindrical with obtuse ends, $115-25(av.\;19.\;5){\times}2.5-4.8{\mu}m(av.\;3.3{\mu}m)$ and setaes were straightly extended above the acervuli, $41.3-136.3\;{\um}m(av.\;85.0{\mu}m)$ long. The fungus produced abundant sclerotia on PDA when it was cultured under darkness. In the inoculation experiments, the fungus was found to infect pepper seedlings and fruits, and fruits of tomato and egg plant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.207-210
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• 2003

"Jangbeol 102" is a new orchardgrass(Dacrylis glomerata L.) variety developed by the National Livestock Research Institute(NLRI) in 2002. To develope the new variety of orchardgrass, 5 superior clones were selected and polycrossed for seed production. Agronomic growth characteristics and forage production of "Jangbeol 102" were examined at Suwon from 1995 to 1998, and regional trials were conducted in Suwon, Namwon and Pyungchang from 1999 to 2002 and Jeju from 2000 to 2002, respectively. "Jangbeol 102" showed semi-erect growth habit in fall and spring and medium to long type in length of flag leaf and upper internode. Plant height of "Jangbeol 102" was similar to that of standard variety, "Ambassador" and heading date was I day faster as 11th May compared to Ambassador. Characters such as winter hardiness, regrowth, moisture tolerance, disease resistance of "Jangbeol 102" were stronger or better than those of Ambassador, specially in regrowth and disease resistance. "Jangbeol 102" showed 18% higher dry matter yield(13,430kg/ha) compared to Amabassador. Nutritive value was appeared to be similar in both varieties.assador. Nutritive value was appeared to be similar in both varieties.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.295-306
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• 2009

We investigated the quality of 48 cultivar in 5 types, most popularly used in Korea golf courses. Only brown patch disease caused by Rhizoctonia solani AG1-1 was occurred naturally. While disease was developed seriously into tall fescue cultivar in spring time and into bentgrass cultivar in fall time, respectively, however, among species were not significantly different. Tall fescue and perennial ryegrass cultivar had higher chlorophyll contents in November and there were also significantly different between cultivar of tall fescue, kentucky bluegrass and fine fescue species. Turfgrass color also showed significant difference between grass species. Perennial ryegrass has the highest value of turf leaf color, followed by kentucky bluegrass and tall fescue species. Significant differences among cultivar were found in kentucky bluegrass, tall fescue and fine fescue. Although fresh weight of turfgrass was not statistically different between grass species, root length was significantly different between species. Tall fescue species had the longest root length. Fresh weight showed differences among cultivar in kentucky bluegrass, bentgrass and tall fescue species. Based on our results, growth and grass quality showed large differences among cultivar and each turfgrass species.

• Research in Plant Disease
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• v.23 no.4
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• pp.355-362
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• 2017

The 4 viruses, the Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV), and Apple mosaic virus (ApMV) and 1 viroid, Apple scar skin viroid (ASSVd) are known major viral pathogens of apple trees in Korea. Infection degree of the 5 viral pathogens in the commercial nursery trees of major apple cultivars, 'Hongro', 'Fuji' and bud mutation of 'Fuji' was investigated. Infection ratio of the ACLSV, ASPV and ASGV for scion of an apple cultivar 'Hongro' were 100%, 81.3% and 100%, respectively. On the other hand, no infection for either ApMV and ASSVd detected. For the root stock of the cultivar, infection ratio of ACLSV, ASPV and ASGV showed 87.5%, 81.3% and 100% as well as ApMV and ASSVd were 12.5% and 6.3%, respectively. From the scion of apple cultivars 'Fuji' and bud mutation of 'Fuji', infection ratio of ACLSV, ASPV and ASGV showed 86.7%, 86.7% and 100%, respectively. Whereas, no infection for either ApMV or ASSVd detected. From the root stock of the cultivars, infection ratio of ACLSV, ASPV and ASGV showed 86.7%, 93.3% and 93.3% as well as ApMV and ASSVd were 12.5% and 6.3%, respectively. Result of our study indicates that most of commercial nursery apple trees were supplied with multiple infections by apple viruses causing potential losses for apple growers and, henceforth, agricultural policy for supply of the virus-free trees should be employed as soon as possible.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.253-259
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• 2008

Soil environmental conditions can affect nutrient availability during growth stage of tree fruit. We investigated the cause of disorderd fruit by the influence of soil chemical properties in orchard soil, composition of mineral nutrient in leaves and fruit to occur physiological disorderd fruit at four locations (Ulsan, Gyeongju, Pyeongtaek, Ansung) compared to healthy. There were significantly different (P=0.05) in exchangeable Ca, K, Mg and total nitrogen content in orchard soil between physiological disordered fruit and healthy fruit. The exchangeable Ca content in orchard soil caused by physiological disordered fruit was statistically lower than that of healthy fruit. However, exchangeable K, Mg and total nitrogen contents were higher than that healthy (P=0.05). There was a significant difference (P=0.05) in Ca content between physiological disordered fruit and healthy. Ca content in fruit flesh of physiological disorderedfruit was statistically lower than that of healthy. The physiological disordered fruit was a higher ratio of Mg/Ca in fruit flesh and peel compared to healthy fruit and also the ratios of N/Ca and K/Ca in a leaf were higher. The negative correlation between Ca and K, and Ca and Mg was detected in the fruit flesh of physiological disordered fruit. Therefore, we concluded that insufficient Ca content in fruit may cause 'the physiological disorder' pomelo disease and high content of N, exchangeable K and Mg ion in the soil solution might be disturbs exchangeable Ca ion to be absorbed in fruit.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.40-45
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• 2018

Potassium in vegetables is known to have an adverse impact on a patient with chronic kidney desease. However, since vegetables also contain many other nutrient, consumption of vegetables by these patients is inevitable. The objective of this study was conducted to develop a fresh lettuce which contains low level of potassium for nephropathy in a closed-type plant factory system. Lettuce of "Charles" was used for experiment. The plants were cultivated in hydroponic system with a 16-h photoperiod at $15-21^{\circ}C$, 65% RH, $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$(LED W:R, 9:1) and $600-650mg{\cdot}L^{-1}$ $CO_2$ during 28 days. Nutrient solution which contains 1%, 5% and 10% potassium compared to conventional composition were supplied at 1 week and 2 weeks before harvest. The content of potassium and macro elements in leafy vegetables were analyzed by ICP emission spectroscopy after harvest. The potassium content in leaf of the 2 weeks before harvest treatment was significantly lower at than control. There were no significant differences between control and treatments in fresh weight and number of leaves. But there were differences among treatments. Considering the vegetable amounts consumed by nephropathy patients, the supply of nutrient which contain 1% and 5% potassium at 2 weeks before harvest was suitable for low potassium lettuce production. This study indicated that low potassium lettuce could be produced by developed nutrient composition and supply method.

• Research in Plant Disease
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• v.8 no.2
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• pp.101-106
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• 2002

For the detection of Tobacco masaic virus (TMV), Tomato mosaic virus (ToMV), and Cucumber mosaic virus (CMV), tomato seeds of 11 table tomato and 7 cherry tomato cultivars were assayed by DAS-ELISA. Among the cultivars, TMV and ToMV were detected from 9 cultivars at the rates lower than 20% and 16%, respectively. In the assay on seed transmission rates, ToMV and CMV were detected as high as 24% and 8% , respectively, but TMV was not detected. In field survey on these viruses from tomato plants of 10 different places in Chungbuk province, ToMV and CMV were detected from most fields. TMV was detected from only 3 fields. The highest detection rates of these viruses were recorded in Cheongwon for TMV Chungju for ToMV, and the other locality of Chungju far CMV. It was difficult to find any relationship between the growth stage of tomato and infection rates. TMV usually caused mosaic on leaves while ToMV caused various symptoms including yellows, necrosis, and mottling. CMV-infected tomato plants showed symptoms of shoestring, fern leaf, and yellows.

• Research in Plant Disease
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• v.17 no.1
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• pp.59-65
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• 2011

One hundred Capsicum accessions were screened for symptomatic response and resistance to Tomato spotted wilt virus-pb1 (TSWV-pb1). Symptom and its severity rating were checked by visual observation at 9, 12, 14, and 45 days after inoculation, respectively. Enzyme-linked immune-sorbent assay was performed all tested individuals on non-inoculated upper leaves after the third rating to indentify viral infection. Leaf curling was predominant in almost susceptible individuals of each accession. Stem necrosis was most frequent in wild species while yellowing in commercial hybrids and Korean land race cultivars. Ring spot, a typical symptom of TSWV, was rarely detected in some of a few accessions. Different levels of resistance to TSWV-pb1 were observed among the tested accessions. High level of resistance was detected in 4 commercial cultivars of Kpc-35, -36, -57, and -62, and 8 wild species of PBI-11, C00105, PBC076, PBC280, PBC426, PBC495, PBC537, and PI201238 through seedling test by mechanical inoculation.

• Research in Plant Disease
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• v.8 no.1
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• pp.59-62
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• 2002

Anthracnose symptoms were observed on the community area in Sancheong-gun, Gyeongnam Province in Korea. The symptoms occurred on leaf and stem, and then plants eventually were died. Colony color was whitish gray to dark gray on potato dextrose agar. Conidia were single celled . colorless, cylindrical and was 10.2~20.4$\times$3.6$\times$6.0$\mu$m in size. Appressoria were dark brown, ovate to obovate and 6.2~10.5$\times$4.3$\times$8.6$\mu$m in size. Perithecia were brown to black in color and shaped as globose to obpyriform and 72.6~284.7$\mu$m in size. Asci were clavate to cylindrical in shape and 63.6~98.8$\times$8.3~12.5$\mu$m in size. Ascospores were cylindrical. fusiform, slightly curved at the center and 9.6~21.8$\times$4.0~6.0$\mu$m in size. Optimum temperature fur growth was 3$0^{\circ}C$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Glomerella cingulata . This is the first report on the Anthracnose of achyranthes caused by Glomerella cingulata in Korea.