• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.14-19
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• 2008

The experiment was investigated the effects of lower root zone temperature on shoot and root growth of 'Akihime' strawberries in aeroponics in cold season. Root growth was decreased with decrease of root zone temperature, especially in lateral roots. Elongation of main roots was highest in $18^{\circ}C$ of root zone temperature. Number of lateral roots and length of lateral roots were lowest in $8^{\circ}C$ of root zone temperature. Lower root zone temperature resulted significantly in decrease of fresh weight of root and shoot and leaf area of strawberry. But there were no significant statistical differences in shoot fresh weight and leaf area in $8^{\circ}C$ and $13^{\circ}C$ of root zone temperature. Leaf length, leaf width and number of leaves of strawberry were decreased in lower root zone temperature. The results of this experiment will be utilized in the winter season cultivation for strawberry in hydroponics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.362-369
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• 1990

In order to determine the mechanism of saline stress, forage plants were irrigated with sea water. Saline stress was investigated on photosynthesis, root respiration, evapotranspiration and visual symptoms. All crops showed increased relative evapotranspiration and relative photosynthesis under low temperature (11-16$^{\circ}C$) rather than high temperature (22-24$^{\circ}C$). The correlation coefficients calculated for each crop between relative evapotranspiration and root respiration were 0.996$\^$**/ for orchard grass, 0.828$\^$*/ for alfalfa and 0.963$\^$**/ for white clover. No significant correlation coefficient between relative evapotranspiration and root repiration was found for the tall fescue. The effects of OED spray on the evapotranspiration and root respiration of crops in the sea watered pots were low compared with those in the fresh watered pots. When OED was sprayed and zeolite was used, the evapotranspiration and root respiration were low compared with check pots and sand pots. The root damage due to sea water treatment was characterized by brown colored root cortex in orchard grass and tall fescue, and water penetration of root cortex in alfalfa and white clover.

• Korean journal of applied entomology
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• v.2
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• pp.27-37
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• 1963

최근 농작물에 대한 각종 선충류의 피해가 주목되어 있는 실성에 비추어 필자는 선충류연구의 기초적 과제로서 온실내의 화훼류 근부에서 발견되는 선충류 중 농업상 비교적 중요하다고 인정되는 종류와 그밖에 몇 종류에 대하여 형태적인 특징을 기술하였다. 즉 취급된 종류들은 다음과 같다. 1. Meloidogyne arenaria Chitwood 2. Scutellonema coheni Andrassy 3. Paurodontus gracilis Thorne 4. xiphinema americaum Cobb 5. Rhabditis sp 6. Cephalobus sp 7, Diplogaster sp 그리고 이상 7종류의 기주식물 및 기생정도를 보면 Meloidogyne arenaria Chitwood는 Begonia에 만 기생하였고 그밖에 화훼류에는 기생을 볼수 없었다. Scutellonema choeni Andrassy는 꽃치자, 소펄, 이마리 리스, 제브리나에 가장 많이 발견되었고, Paurodonthus gracilis Thorne는 동백나무, 청목. 지내고사리, 카네이션, 충에서 가장 많이 발견되었다. 그리고 Xiphinema americanum Coob는 산호수, 서향, 코피나무, 시크라맨, 용설란, 동백 등에서만 발견되었으나 그중에 용설란, 동백에서 가장 많이 볼 수 있었다. Rhabditis sp.는 초본류 화훼류의 대부분에서 발견되었으나 그중에도 산세배리아에서 가장 많았다 Diplogaster sp는 대부분의 화훼류에서 발견되었으며 그중에 크로톤에 비교적 많았다. Cephalobus sp.는 전반적으로 발견되었으며 발견정도는 모두 비슷하였다. Monhystera app. , Mononchus spp. , Dorylaimus app. 등도 조사란 과반수의 화훼류들에서 발견되었으나 특히 많이 발견되는 화훼류는 없었다. 이상 선충류중 근류를 형성하여 피해가 가장 주목되는 Mceloidogyne arenaris Chitwood에 대해서 온실내에서 그의 유일한 기주식물인 Begonia의 품종별 기생정도를 비교조사한 결과 semperflorens 품종에 가장 기생률이 높았고 metarica 품종은 중정도였으며 erytholopylla와 argento-guttata 품종들에는 기생이 없었다. 이 점은 매우 의의있는 사실로서 앞으로 더욱 연구할 과제로 삼았다. 끝으로 Sanceberia에서 많이 발견되는 Rhabditis sp를 $18^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$의 동온도별의 incubator에서 사육한 결과 본 종의 생육적온이 $30^{\circ}C$라는 사실을 알았다.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.321-328
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• 1987

In order to examine the factors affecting herbicidal injury of pepper, crop injury and growth response of 2 red pepper cultivars and 2 sweet pepper cultivars to napropamide and pendimethalin were evaluated under defferent conditions of soil texture, organic matter, soil temperature and seeding depth in the greenhouse. Growth response of 4 pepper cultivars was also examined by roos dipping to napropamide and pendimethalin. More inhibition of top leaf growth by root dipping to napropamide was occurred in red pepper cultivars than in sweet pepper cultivars. However, sweet pepper cultivars showed more severe inhibition of top leaf growth by root dipping to pendimethalin compared to red pepper cultivars. Crop injury due to napropamide and pendimethalin was more severe in sandy soil than in loam soil and this trend was more remarkably shown in sweet pepper cultivars. Crop injury due to napropamide and pendimethalin was reduced with the increase in organic matter especially in cv. Walgeykwan and cv. Orient al Pimento. As seeding depth of pepper cultivars became deeper, crop injury due to napropamide and pendimethalin was reduced in cv. Walgyekwan and cv. Oriental Pimento.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.473-474
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• 2009

In this study, a column member of an existing architecture finished with gypsum board was assumed to examine fire resistance characteristics according to the type and thickness of finishing material. All specimens showed spalling to the reinforcing part after fire resistance test. For temperature characteristics, rapid temperature increase of 100${\sim}$200 $^{\circ}C$ was shown between 35 ${\sim}$ 60 minutes in the sequence of 9.5 T, 9.5 T (2 pieces), 12.5 T, 15 T and fire resistant 12.5 T. The analysis suggested that finishing materials with better fire resistance are necessary.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.181-187
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• 1995

Cylindvocarpon destmtalns isolate CY-92-01, pathogen of root-rot of Panax ginseng showed t the maximum mycelial growth on the Czapek solution agar among the thirteen kinds of media. Five isolates (Isolate CY-92-01, CY-92-03, CY-92-07, CY-94-01, CY-94-02) of C. destructan from various growth stages of p. ginseng recovered from several geographical sites also showed maximum growth in the Czapek-Dox broth compared with potato dextrose broth and V-8 juice broth. Rapid growth rate was maintained until 12 days after inoculation on the Czapek-Dox broth and mycelial weight was somewhat constant until 20 days. After 30 days of incubation, the mycelial weight began to decrease. The fungal growth occurred from 5$^{\circ}C$ to $25^{\circ}C$ and optimum temperature for growth was 2$0^{\circ}C$. Mycelial weight orderly decreased at 15, 25, 10, and 5$^{\circ}C$. Quantitative measurement was impossible at 5$^{\circ}C$. No fungal growth was occurred at the temperature higher than 3$0^{\circ}C$. Growth was observed at all tested pH ranges from 2.8 to 8.0. Optimum pH for growth was 4.0~5.0 followed by pH 3.3~3.5 and 5.4~6.0. The least growth occurred at pH 2.8.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.292-300
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• 1996

This experiment was conducted to investigate the factor of phytotoxicity for herbicides(bensulfuron methyl, pyrazosulfuron-ethyl, dimepiperate, molinate) on flood direct-seeded rice. The phytotoxicity of herbicides was evaluated under controlled environment condition. Bensulfuron methyl and pyrazosulfuron-ethyl reduced more rice growth, especially root growth on low temperature(20/$11^{\circ}C$) than high temperature(30/$22^{\circ}C$) cultivations. The phytotoxicity of bensulfuron methyl and pyrazosulfuron-ethyl were increased relatively by non-nutrient and nutrient solution. cultivation, respectively. The rice applied bensulfuron methyl and pyrazosulfuron-ethyl with pH 3.5, 5.5, 7.5 and 9.5 solution became low growth rate on low pH of pH 3.5 and 5.5 solution cultivation. Bensulfuron methyl application with pH 5.5 and pH 7.5 solution, and pyrazosulfuronethyl application with pH 7.5 and 9.5 solution reduced rice growth inhibition. The root growth of rice seeded in 6cm depth of water solution applied herbicides was suppressed by bensulftuon methyl and pyrazosulfuron-ethyl, the growth of shoot was suppressed heavily by dimepiperate and molinate, in particular dimepiperate suppressed about the growth of 90%. The phytotoxicity of pyrazosulfuron-ethyl became high on light clay soil of non-fertilizer condition and sand loam soil of fertilizer condition, bensulfuron methyl became high on sand loam soil.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.405-408
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• 2008

This study, as mock-up test for applying Polylon Fiber engineering method to the field, analyzed the fundamental characteristics and the fireproof characteristics of high strength concrete mixed with Polylon Fiber 0.05% and the results are summarized as followings. From the characteristic of the fresh concrete, both slump flow and air content were appeared to satisfy target range. And from the characteristic of hardened concrete, all compressive strengths according to the curing conditions were appeared to satisfy design standard strength of 60 MPa. From the fireproof characteristic, small scaling and spalling phenomenon were partially appeared on the surface part of specimens, but generally the excellent fireproof capacities were appeared. From the characteristic of temperature hysteresis, the highest temperature and the average temperature of reinforcing part after fire-resistant test for 3 hours were $531^{\circ}C$ and $405{\circ}C$, respectively and then satisfied fireproof standard of the Ministry of Land Transportation and Maritime Affairs.

• Journal of Ginseng Research
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• v.20 no.1
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• pp.88-95
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• 1996

The effects of media, incubation time, temperature and pH on production of conidia and chlamydospore of Cylindrocarpon destructans (Zinssm.) Scholen causing root rot of Panax ginseng were studied. Microconidia of the pathogen were abundantly produced on V-8 juice agar as a solid substrate with 5.73(log conidia/mm2) and in V-8 broth as a liquid substrate with 6.65 (log conidia/ml) among media tested. No difference was observed on the length of microconidia produced from the media with a range of 9.50∼11.38 $\mu\textrm{m}$. However, tryptic soy agar produced the broadest microconidia (average 5.00 $\mu\textrm{m}$) among the media tested. All the media produced chlamydospores In a range of 1.06∼4.37 (log chlamydospores/mm2) without a significant difference in number, while V-8 juice agar produced the bigger one (18.39 $\mu\textrm{m}$ in diameter) as compared to the tested media. The fungus began to sporulate conidia after three days of incubation and reached maximum at the 8th day. It seemed to be in a stationary phase until 30 days of incubation but was decreased thereafter. Chlamydospore was produced at 4th day after incubation. Maximum production was observed at 8th day and the number seemed to be maintained during the observation period. Both conidia and chlamydospore of the pathogen were able to be spoluated at 10∼25$^{\circ}C$. However, optimum temperatures of conidia and chlamydospore formation were 15∼25$^{\circ}C$ and 10∼20$^{\circ}C$, respectively. C. destrmtans produced conida with an wide range of pH from 3.3 to 8.0 and chlamydospore from 2.8 to 8.0. Number of conidia was increased with an increase of pH up to 4.0. There was no significant difference in the number between 4.0 to 8.0. It seemed to have two optimum pH ranges, 3.3∼4.0 and 7.1∼8.0 for the chlamydospore formation.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.142-146
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• 1984

Soils suppressive and conducive to ginseng root rot were studied by examining the mycelial growth of Fusarium solani, Phytophthora cactorum, and Sclerotinia sp. on extracts of each type soil. Rhizosphere environments of the two soils were also compared. Mycelial growth of all root rot fungi used was more severely restrained on the suppressive soil extract agar than that of conducive one. However, when heated at 100C for 30 minutes, mycelial growth of F. solani and Sclerotinia sp. was not affected, regardless of type soil used, whereas R. solani and P. cactorum grew better on conducive soil extract. Mycelial growth of all fungi used was stimulated as the treated temperature became higher. No significant differences between the two types of the soil were found in propagules of F. solani. The numbers of total fungi and total bacteria and the ratioes of total fungi to Fusarium and total bacteria to Fusarium were higher in the suppressive soils than in the conducive ones. Higher amount of clay existed in the suppressive soils, Mg and Na contents were lower in those soils than the conducive ones.