• International Journal of Industrial Entomology and Biomaterials
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• 제9권1호
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• pp.79-87
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• 2004

The silkworm rearing and growth parameters of 63 multivoltine silkworm accessions under extended period of egg preservation at 5$^{\circ}C$ from 30 days to 45 days were studied. The results indicate that, nine accessions did not respond to extended period of egg preservation at low temperature and the remaining 54 accessions responded to the treatment and three rearings were conducted for comparision with the control; to estimate the effect of prolonged egg preservation at low temperature. The non-parametric tests statistics (Wilcoxon tests) was adopted for comparing the mean performance of treated batches (45 days) over the control (30 days). Highly significant variability was found among the accessions for all the parameters under study. The genetically controlled morphological characters were not altered in the treated batches, which were found to be on par with that of control. However, the total larval duration varied significantly over the control in 51 accessions. Similarly, the fifth age larval duration of 27 accessions showed decreasing trend compared to control. Altogether 41 accessions were found to be tolerant to long-term cold preservation upto 45 days, without showing any significant variation for morphological as well as essential quantitative traits. These accessions may be recommended for long-term egg preservation schedule up to 45 days, which will reduce the cost of conservation of these silkworm germplasm.

• 한국작물학회지
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• 제38권2호
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• pp.189-195
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• 1993

본시험은 유ㆍ무한신육형콩의 생육 및 수량형질의 차이와 그 변이 정도를 구명하고 콩 육종 및 재배의 기초자료를 얻고자 1990년 수원 작물시험장에서 실시하였다. 유한신육형인 황금콩과 장엽콩, 무한신육형인 Clark와 Qilliams를 공시하여 재식밀도는 휴폭을 60cm로 동일하게 하고 주간을 10cm (밀도, 33개체/$m^2$), 15cm(표준, 22개체/$m^2$) 및 20cm(소식, 16개체/$m^2$)로 달리하여 생육 및 수량형질의 재식밀도 반응을 검토한바 그 주요결과를 요약하면 다음과 같다. 1. 단위면적당($m^2$) 분지수와 분지절수는 유한신육형이 무한신육형 보다, 단위면적당($m^2$) 주경절수는 무한신육형이 유한신육형 보다 많았으며 밀식일수록 증가하였다. 2. 단위면적당($m^2$) 입종은 유한신육형이 무한신육형보다 많았고, 밀식일수록 많았다. 3. 수량구성요소의 주경의존도는 밀식일수록 높아 졌는데 이러한 경향은 유한신육형 보다 무한신육형에서 더 컸다. 4. 입경비는 무한신육형이 유한신육형 보다 높았으며 소식일수록 증가하였고,면적경중은 유한신육형이 무한신육형 보다 많았으며 밀식일수록 증가하였다. 5. 개체간 변이 분석 수량형질 > 개체전체의 수량형질 > 주경의 수량 형질 > 주경의 형태적 형질 및 100입종의 순으로 컸으며 유ㆍ무한신종육형간에 뚜렷한 차이는 분지 관련 형질이었다. 6. 재식밀도 변화에 따른 개체간 변이의 변동이 큰 형질은 분지의 수량형질로서 무한신육형이 유한신육형에 비하여 변이폭이 컸다.

• Parasites, Hosts and Diseases
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• 제24권1호
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• pp.55-62
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• 1986

실험감염된 횐질와 마우스에 있어서 Pygidiopsis summa의 성장발육 과정을 관찰하는 한편 이 흡충의 형태학적 특징으로서 이집트산인 P. genata와의 차이점에 대하여 재검토하였다. 피낭유충은 전북 옥구산 어린 숭어(Mugil sp.)에서 획득하였고 흰쥐 21마리 및 마우스 21마리에 각각 1,000개씩 경구감염시켰고 감염 3일부터 28일까지 충체를 회수하여 형태학적 관찰을 시행하였다. 충체의 성장발육은 그 크기에 있어서 감염 10일까지의 급속한 성장과 그 후의 성장정지로 특징지을 수 있었고 감염 10일된 성충의 크기는 길이 0.53∼0.82mm, 폭 0.31∼0.39mm이었다. 한편 충체의 생식기관인 고환, 난소, 생식장치(genital apparatus), 난황선 등은 매우 급속한 성장발육을 보여 감염 3∼5일에 모두 성숙하였고 이때 이미 자궁내에는 충란이 형성되어 있었다. 생식장치내의 좌우에는 각각 5∼6(우측)개 및 7∼9개의 소극(small spines)이 이 흡충의 새로운 형태학적 특징으로서 관찰되었고, 타원형이며 약간 비스듬히 체 중앙선에서 측면으로 치우친 복흡반(ventral sucker), 끝이 체 중앙부로 꼬부라지지 않고 고환 전방까지 뻗어 있으며 팽대되어 끝나있는 충체 복관(ceca), 등이 P. genata와는 다른 특징적 형태로 판단되었다. 따라서 P. summa는 분명히 P. genata와는 다른 별개의 종으로 생각되었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제31권2호
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• pp.107-114
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• 2015

Endophytes provide multifarious benefits such as promotion of plant growth and yield, suppression of phyto-pathogens, phosphate solubilising and fixation nitrogen. A study has been carried out to explore growth promotion and antifungal activities of endophytes of mulberry (Morus spp.). Endophytic bacteria were isolated from mulberry plants and studied their cultural, morphological characters, growth promotion as well as their antifungal activity against Rhizoctonia bataticola and Fusarium oxysporum , two mulberry root rot associated pathogens. Except two isolates, all bacteria were colourless and the colony size of eight isolates was small. The margin of five isolates was irregular and the consistency of three isolates was creamy, six isolates was slimy and one was mucoid. Texture of seven isolates was convex and others were flat. Eight isolates were gram positive and the rest Gram negative, five were cocci and others were bacilli (rod shaped). Four isolates were motile and all were catalase positive and only three isolates were oxidase positive. Spore staining was positive only for two isolates. The growth promotion study showed that there was significant difference in root length and seedling length. The antagonistic effect of the bacterial isolates was tested against R. bataticola showed significant (p <0.05) influence of the bacteria, days after inoculation and their interaction on the inhibition of fungal growth. The isolate En-7 completely inhibited the fungus followed by En-5 (66.67%). The bacterial isolates significantly (p <0.05) inhibited growth of F. oxysporum in PDA. The mean inhibition was higher (70.45%) in case of En-7 followed by En-8 (68.65%) and En-10 (66.44%). The study reveals that some endophytic bacteria associated with mulberry have growth promotion and antifungal activity and could be explored for promotion of mulberry growth and managing root rot disease.

• 한국토양비료학회지
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• 제47권3호
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• pp.141-146
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• 2014

The necessity to develop economical and eco-friendly technologies is steadily increasing. Plant growth promoting rhizomicrobial strains PGPR are a group of microorganisms that actively colonize plant roots and increase plant growth and yield. Pot experiments were used to investigate the potential of some rhizobacterial strains to enhance the Brassica rapa growth. Microbial strains were successfully isolated from the rhizosphere of Panax ginseng and characterized based on its morphological and plant growth promotion characters. Surface disinfected seeds of Wisconsin Fast B. rapa were inoculated with the selected PGPR microorganisms. The different pots treatments were inoculated by its corresponding PGPR ($10^7cfu\;mL^{-1}$) and incubated in the growth chamber at $25^{\circ}C$ and 65% RH, the light period was adjusted to 24 hours (day). NPK chemical fertilizer and trade product (EMRO, USA) of effective microorganisms as well as un-inoculated control were used for comparison. Plants harvested in 40 days were found to have significant increase in leaf chlorophyll units and plant height and also in dry weight of root and shoot in the inoculated seedlings. Root and shoot length and also leaf surface area significantly were increased by bacterial inoculation in sterile soil. The study suggests that Rhodobacter capsulatus and Azotobacter chroococcum are beneficial for B. rapa growth as they enhance growth and induced IAA production and phosphorus solubilization. This study presents some rhizomicrobial strains that significantly promoted growth of Wisconsin Fast Plant B. rapa in pot experiment under different soil conditions.

• 한국작물학회지
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• 제49권6호
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• pp.487-490
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• 2004

두채생산에서 관수는 상면살수 방식과 하면담수 방식으로 대별된다. 본 연구는 관수방식에 따른 숙주나물의 생산과 상품성에 관한 정보를 제공하고자 중록1호를 공시재료로 상면살수와 하면담수 방식으로 대별되는 관수방식의 차이가 숙주나 물의 생장, 형태, 색도, 전단력과 재배용기내의 온도변화를 조사하고자 실시되었으며, 그 결과를 요약하면 다음과 같다. 1. 품질과 밀접히 관련된 세근은 하면담수 방법으로 재배할 경우 전혀 형성되지 않았던 반면, 상면살수 방법으로 재배할 경우 일부 개체에서 발생되는 것으로 조사되었다. 2. 하배축은 상면살수 방식에서, 뿌리는 하면담수 방식에서 길었으나, 하배축과 뿌리 길이를 합한 전체길이와 하배축 중간 및 자엽 바로 아래의 직경은 관수방법간에 차이가 없었다. 3. 개체당 전체건물중은 관수방법간에 차이가 없었던 반면, 전체생체중은 하면담수 방식보다 상면살수 방식에서 많았다. 이러한 차이는 주로 하배축 생체중의 차이에 기인되는 것으로 나타났다. 4. 두 관수방법 모두 재배중 플라스틱통 및 재배기내의 온도가 상승되었으나, 상면살수 방식에 이용되는 플라스틱 재배 통 내의 온도 상승이 큰 것으로 측정되었다. 이러한 온도 상승이 하면담수 방식보다 상면살수 방식에서 하배축 및 개체당 전체 생체중을 증가시킨 원인으로 해석되었다.

• Mycobiology
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• 제38권4호
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• pp.274-281
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• 2010

Cordyceps cardinalis was reported in Japan and the USA in 2004, and its fruiting bodies have recently been cultured in Korea. Herbarium specimens preserved at the Cordyceps Research Institute, Mushtech, Korea were revised and identified as C. cardinalis, based on morphological characters and conidial structures. Most of the C. cardinalis specimens were collected from Mt. Halla in Jeju-do. The effects of various nutritional sources and environmental conditions such as temperature and pH on mycelial growth of C. cardinalis were studied. Oatmeal agar, Martin's peptone dextrose agar, and Schizophyllum (mushroom) genetics complete medium plus yeast extract resulted in the best mycelial growth. Among carbon sources, cereals, and nitrogen sources, maltose, oatmeal, and peptone resulted in the best mycelial growth respectively. Mineral salts helped to increase growth rate but only resulted in thin mycelial density, similar to water agar. A temperature of $25^{\circ}C$ and a pH of 7 resulted in the highest mycelial growth. Based on these results, a Cordyceps cardinalis composite medium (CCM) was formulated with 1% maltose, 2% oatmeal, 1% peptone, and 2% agar. Use of the CCM resulted in slightly better mycelial growth than that of other commonly used agar media. Only organic nitrogen sources imparted a reddish pigmentation to the agar media, but this character diminished after several subcultures. A 7 day culture duration resulted in the best mycelial growth.

• 한국산림과학회지
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• 제98권2호
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• pp.170-177
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• 2009

There are remarkable differences in growth and morphological characters of roots between mountain and field cultivated Panax ginseng. Growth of root in mountain cultivated ginseng was much slower than that of field cultivated ginseng. However, the factor affecting the retarded growth in mountain ginseng was not known. Soil analysis revealed that phosphorus (P) content of mountain soil was exceptionally low at least ten-fold lower compared to that of field soil. Thus, we suggest that low availability of P in mountain soil may be one of the limiting factors for growth of ginseng in mountain soil environment. We had monitored the growth of ginseng plants after one and three years of phosphate fertilizer application. Three kinds of phosphate fertilizers: fused magnesium phosphate, fused superphosphate, and single superphosphate were applied to mountain soil. Application of phosphate fertilizers increased the fresh-, dry weight, and diameter of ginseng roots and resulted in increased P accumulation in roots. These results demonstrate that slow growth of ginseng in mountain soil environment might be attributed to the low P content in mountain soil. Thus, analysis of P amount in mountain soil will be a good indicator for the selection of suitable site the ginseng cultivation in forest.

• 한국패류학회지
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• 제27권2호
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• pp.91-97
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• 2011

This study examines the morphological features of larval and postlarval shells of the paedomorphic bivalve Crenella decussata Montagu, 1808 from the Sea of Japan. During the early morphogenesis of the shell of C. decussata the following characteristics appear: prodissoconch I -the anterior and posterior provincular teeth, a broad primary ligament pit located on the chondrophore; nepioconch - the anterior and posterior juvenile teeth,primary lateral teeth, fine commarginal and radial sculpture. Larvae of C. decussata distinctly differ from other mytilid larvae by a D-shaped shell, absence of umbo, astraight hinge margin, and homogeneous fine-grained sculpture without co-marginal lines of growth. These shell characters indicate lecithotrophic development of this species. Some morphostructures are revealed which might be used in crenellin taxonomy.

• 한국작물학회지
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• 제56권1호
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• pp.35-43
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• 2011

Thirty five isolates of Trichoderma species collected from seven different locations of Bangladesh were studied for morphological characters and molecular variation. Mycelial diameters of the isolates varied from 8.28 cm to 9.00 cm. Based on colony colour, isolates were grouped into five such as dark green, green, light green, yellowish green and whitish green. Maximum isolates were green and light green. On the basis of growth habit and colony consistency, the isolates were categorized into three groups, in which most species had fast growth and were compact in appearance. PCR-based Random Amplified Polymorphic DNA (RAPD) technique employing 3 decamer primers produced 36 scorable bands of which all (100%) were polymorphic. The co-efficient of gene differentiation (Gst) was 1.0000 reflecting the existence of high level of genetic diversity among the isolates. The Unweighted Pair Group Method of Arithmetic Means (UPGMA) dendrogram constructed from Nei's (1972) genetic distance produced 2 main clusters (13 isolates in cluster 1 and 22 isolates in cluster 2). The result indicating their genetic diversity has opened new possibility of using the most efficient and more isolates of Trichoderma in the preparation of biopesticide and decomposition of municipality waste.