• Title/Summary/Keyword: Fresh Water

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Isolation and Morphological Identification of Fresh Water Green Algae from Organic Farming Habitats in Korea (유기농업 생태계로부터 담수 녹조류 분리 및 형태적 동정)

  • Kim, Min-Jeong;Shim, Chang-Ki;Kim, Yong-Ki;Hong, Sung-Jun;Park, Jong-Ho;Han, Eun-Jung;Jee, Hyeong-Jin;Yun, Jong-Chul;Kim, Suk-Chul
    • Korean Journal of Organic Agriculture
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    • v.22 no.4
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    • pp.743-760
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    • 2014
  • This study aimed to isolate and identify freshwater algae from the organic agricultural ecosystems and investigate its biological characteristics to study the possibility of utilizing a biomass freshwater algae in organic farming. In the survey area, average water temperature was $12.4{\sim}28.2^{\circ}C$ and the pH ranges were from 6.1 to 8.5. The solid culture method is more suitable than liquid culture method for isolation of freshwater algae with lower contamination level and higher isolation frequency. A total of 115 strains were isolated from six freshwater algae habitats in nine regions in Korea. BGMM (BG11 Modified Medium) amended with NaNO3 and $KNO_3$ as a nitrogen, and $Na_2CO_3$ as carbon source was designed to isolate and culture freshwater algae. Absorbance of freshwater algae culture has increased dramatically to four days and decreased after eight days after inoculation. CHK008 of the seven isolates showed the highest absorbance in seven days after culturing in BGMM. The optimal pH of BGMM for culturing freshwater algae was pH 6-7. As light intensity increased, growth of freshwater algae increased. Among the five kinds of carbon sources, glucose and galactose promoted good growth of freshwater algae in BGMM. The colony color of purified 16 green algae isolates showed a separation of green, dark and light green, and of them, eleven algae strains showed a strong fluorescent light under fluorescence microscopy. Cell size of the green algae showed a wide range of variation depending on the species. General morphology of the green algae strains was spherical. Chlamydomonas sp. was elliptical, and Chlorella sorokiniana was ellipsoidal and cylindrical. All strains of the green algae except for Chlamydomonas sp. did not have flagella. One isolate of Chlamydomonas sp. and five isolates of C. sorokiniana secreted mucus. Sixteen isolates of 16 green algae were identified as two family and six species, Chlorella vulgalis, C. sorokiniana, C. pyrenoidosa, C. kessleri, C. emersonii, and Chlamydomonas sp. based on their morphological characteristics.

Free Amino Acid and Polysaccharide Content of Submerged Mycelial Culture of Fomitopsis pinicola (귤피 및 녹차추출물에서 배양한 소나무잔나비버섯(Fomitopsis pinicola) 균사체의 유리아미노산 및 다당류 함량)

  • Jang Kyung-Ho;Shin Kyung-Ok;Kim Soon-Dong
    • Food Science and Preservation
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    • v.12 no.4
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    • pp.379-386
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    • 2005
  • Free amino acids and polysaccharide content of submerged mycelial culture of Fomitopsis pinicola using $2\%$ citrus peel water extracts(CP), $2\%$ green tea water extracts(GT) and yeast-malt broth(YM) were investigated. Cultivations were conducted at $30^{\circ}C$ and 150 rpm for 10 days. Yields of the mycelium as fresh weight basis in GT-, CP- and YM-broth were $42.3\%,\;34.2\%\;and\;9.89\%$, and their turbidity(OD at 660 nm) of the broth without mycelium were 0.14, 0.16 and 0.22, respectively. Total free amino acid content in the mycelium were 928.19 $mg\%$ in YM, 1060.53 $mg\%$ in CP, 764.83 $mg\%$ in GT, and the major free amino acid was lysine in YM, glutamic acid in CP and GT. Total free exo-amino acid contents were 659.75 $mg\%$ in YM, 954.55 $mg\%$ in CP, 838.69 $mg\%$ in GT, and the major in the all broths was glutamic acid Total amino acid derivatives content of the mycelium were in order of CP>GT>YM, and the major was cystathionine in YM, hydroxy proline in CP and GT. The major among exo-amino derivatives was hydroxy proline in the all broth. Exo-AIS content was in order of CP>GT>YM. Acid soluble polysaccharide content of the mycelium was GT($0.69\%$)>YM($0.39\%$)>CP($0.18\%$). The exo-polysaccharide content was in order of GT($0.87\%$)>CP($0.69\%$)>YM($0.09\%$). Alkali soluble polysaccharide content of the mycelium was in order of CP($5.21\%$)>GT($5.18\%$)>YM($4.56\%$), and exo-polysaccharide was in order of GT($6.79\%$)>YM($3.57\%$)>CP($3.01\%$). The alkali soluble polysaccharide eluted from mycelium cultivated in CP broth was supposed to polysaccharide(about 500,000 daltons) composed of hexose and uronic acid bounded with protein(below 10,000 daltons).

Effects of Different Natural Extracts and Plant Growth Regulators on Plant Regeneration and Callus Induction from Pseudobulbs Explants through in vitro Seed Germination of Endangered Orchid Bulbophyllum auricomum Lindl. (멸종 위기에 처한 Bulbophyllum auricomum Lindl. orchid의 시험관 내 종자 발아를 통한 구근 절편체의 식물 재생 및 캘러스 유도에 대한 천연 추출물 및 식물 성장 조절제(PGR)의 효과)

  • Aung, Win Theingi;Bang, Keuk Soo;Yoon, Seo A;Ko, Baul;Bae, Jong Hyang
    • Journal of Bio-Environment Control
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    • v.31 no.2
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    • pp.133-141
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    • 2022
  • Bulbophyllum auricomum Lindl. is a rare orchid and has flowers with an attractive fragrance. The present study investigated the tissue culture method for micropropagation. Capsules derived from artificial self-pollination were obtained for the best seed germination in MS basal medium. Plant growth regulators (1.0 mg·L-1 of BAP and 2.0 mg·L-1 of NAA) were affected by callus induction from subcultured pseudobulb explants. For the callus subculture, different natural plant extracts were tested in 11 treatment media. Among them, MS medium with 150 mL·L-1 of coconut water was generally effective in fresh weight (1.75 ± 0.08) and (3.01 ± 0.20) of callus proliferation and PLBs induction at 1 and 2 months, respectively, followed by an MS combination of 30 g·L-1 of banana and 20 g·L-1 of potato extract. The results of a comparative study of different MS mediums containing plant growth regulators with a natural extract combination and MS medium supplemented with natural extract only showed that MS medium supplemented with a combination of natural extracts (150 mL·L-1 of coconut water) and plant growth regulators (2.0 mg·L-1 of BAP and 1.0 mg·L-1 of NAA) obtained the highest shoot regeneration (3.37 ± 0.17) and (6.41 ± 0.68) after 1 month and 2 months of culturing, respectively.

Studies on the Nutritional Effects of Locally Produced Dried Formula Milk and Fermented Milk -1. Comparative Studies on the Nutrients Content of Dried Formula Milk and Fermented Milk- (국산(國産) 조제분유(調製粉乳)와 발효유(醱酵乳)의 영양효과(營養效果)에 관(關)한 연구(硏究) - 1. 유제품(乳製品)의 영양소(營養素) 함량비교(含量比較)를 위한 연구(硏究) -)

  • Paik, Jeong-J.;Han, In-K.
    • Journal of Nutrition and Health
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    • v.9 no.1
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    • pp.84-91
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    • 1976
  • Chemical determination were made to analyze the concentration of nutrients including proximate composition, vitamins, minerals, amino acids and fatty acids in three kinds of locally produced infantile formula milk(DFM) and one fermented milk(FM). An attempt was also made to compare the analytical values of nutrients against guaranteed values. The results obtained are summarized as follows; 1. The analyzed value of protein and fat content in DFM-A.B.C was slightly lower than that of guaranteed values and a reverse trend was observed in the case of total carbohydrate. There were no differences in proximate composition among the three kinds of DFM. It was found that the FM contained less protein and fat than the fresh milk, but it seemed that a considerable amount of sugar was added to FM. 2. The analyzed values of vitamin $A(2{\sim}3\;times)$ and $E(4{\sim}6\;times)$ contents in DFMS were higher than those of the guaranteed values except niacin. There were a little differences in vitamin contents among DFMS analyzed. 3. In the case of minerals, the analyzed values were similar to the guaranteed values except the calcium concentration that analyzed value was much higher than guaranted value. When the DFMS were diluted to 15% by adding water to compare with the human and fresh cow milk, it was found that the diluted DFMS resembled the human milk rather than cow milk in the content of energy, carbohydrates, protein and ash. The higher contents of iron and most vitamins in the diluted DFMS than the human milk or cow milk would indicate that they were fortificated with these nutrients. When these diluted DFMS were compared with the Korean R.D.A. for infant, it was clear that they could supply sufficient amount of the nutrients required by R.D.A. except the niacin which failed to reach the recommended level. The fact that iron content of DFM-C was not sufficient while vitamin A supply was excessive by 6 fold would indicate that further studies for the improvement may be necessary. 4. There was a little difference among DFMS in amino acid composition. The similarity of the essential amino acids composition between DFMS and cow milk indicated that there was no modification of the essential amino acids. However, present data showed that the amino acid compositon of FM was similar to that of the cow milk. 5. There was no difference among DFMS in the degree of saturation of fatty acids. The similar or higher levels of essential fatty acids contents of DFMS as compared with human milk revealed that essential fatty acids were added to DFMS during the course of process. From the experimental results described above, it may be concluded that the nutritive effects of three kinds of locally produced DFMS were much alike. It was also found that macro and micro nutrient composition except amino acid composition of locally produced dried formula milk was very much similar to that of the human milk. Moreover, fortification of iron and vitamins resulted in improving their nutritive values as the single form of infantile food, but it seemed that more consideration should be given on the fortification of some nutrients.

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Food Components of Wild and Cultured Fresh Water Fishes (천연 및 양식산 담수어의 식품성분)

  • KIM Kyung-Sam;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.3
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    • pp.195-211
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    • 1986
  • The object of this study is to obtain fundamental data on cultured fishes produced in Korea to improve their food components. For this purpose, the food components of cultured fresh water fishes such as eel, Anguilla japonica, snakehead, Channa argus, and common carp, Cyprinus carpio, were investigated and compared with those of the wild ones. The results obtained are summarized as follows: 1. Common characteristics in the proximate composition were that wild fish was higher in crude protein content and lower in crude lipid content than those of cultured one. 2. Among the 9 kinds of minerals analyzed in all the samples, sodium, potassium, calcium and magnesium contents were absolutely predominant being more than $99.52\%$. These four elements in feedstuff also occupied $99.68{\sim}99.92%$ of total minerals. 3. The neutral lipids of wild and cultured eel, snakehead and common carp occupied $55.7{\sim}95.8%$ of lipid fractions, while the content of the phospholipids in snakehead was particularly higher than those of others. 4. The neutral lipids of wild and cultured eel, snakehead and common carp mainly consisted of triglycerides ($85{\sim}95%$), and a little quantity of diglycerides, monoglycerides, free sterol ester and hydrocarbon were also identified in the neutral lipid. 5. The phospolipids of eel and common carp were mainly occupied by phosphatidyl choline ($71.3{\sim}83.9%$), followed by phosphatidyl ethanolamine ($12.1{\sim}23.5%$) and phosphatidyl serine ($7.5{\sim}13.8%$). The phospholipids of snakhead consisted of phosphatidyl choline ($50.7{\sim}64.5%$), phosphatidyl ethanolamine ($28.0{\sim}35.5%$) and phosphatidyl serine ($7.5{\sim}13.8%$). Generally, phosphatidyl choline content was higher in wild fish than in cultured one, while phosphatidyl ethanolamine and phosphatidyl serine contents were higher in cultured one. 6. The major fatty acids in total lipid of wild eel, snakehead and common carp were $C_{16:0}\;and\;C_{20:5}$, while those in cultured ones were $C_{18:1},\;C_{18:2}\;and\;C_{22:6}$. The fatty acid composition of neutral lipids showed similar tendency to that of total lipid, and the main fatty acids in phospholipids of cultured fishes were $C_{18:1}\;and\;C_{18:2}$. In glycolipids, $C_{20:5}\;and\;C_{22:6}$ were higher in wild fishes, while $C_{18:2}$ were higher in cultured ones. 7. Total amino acids contents of wild and cultured eel were nearly the same, being $16.65\%$ ana $15.99\%$ respectively. The major amino acids of wild and cultured fish were glutamic acid, leucine, aspartic acid and lysine in order. In snakehead, the contents of aspartic acid and proline in cultured fish were higher than those in wild one, while the contents of glutamic acid, alanine, glycine were higher in the wild one. Total amino acid content of cultured common carp was $21.7\%$ compared with $17.08\%$ in wild one. The contents of glutamic acid, aspartic acid, glycine, proline and alanine occupied higher quantities in cultured common carp compared with those in wild one while the other amino acids revealed no significant difference. 8. Aspartic acid in free amino acids of cultured eel held $1.0\%$ of total free amino acids, while that in wild eel held $2.9\%$. Histidine, arginine and tyrosine content of cultured fish were two times higher than those of wild one. But free amino acid composition of samples seemed to be no marked differences according to cultured places. The contents of arginine, aspartic acid, glutamic acid, methionine and phenylalanine of snakehead ware higher in wild one than in cultured one, while the contents of lysine, histidine, glycine, and alanine ware higher in cultured one. In free amino acids content of wild common carp, histidine, glycine and lysine occupied $76.9\%$ of total free amino acids. Lysine, histidine, aspartic acid, alanine, valine and leucine were higher in wild one compared with those of cultured one, while glycine and tyrosine contents were higher in cultured fish.

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Prophylactic and therapeutic studies on intestinal giant-cystic disease of the Israel carp caused by Thelophanellus kitauei II. Effects of physical and chemical factors on T. kitauei spores in vitro (향어의 장포자충(Thelohanellus kitauei)증의 예방 및 치료에 관한 기초적 연구 II. 물리화학적 요인이 장포자충 포자에 미치는 영향)

  • Lee, Jae-Gu;Kim, Jong-O;Park, Bae-Geun
    • Parasites, Hosts and Diseases
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    • v.28 no.4
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    • pp.241-252
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    • 1990
  • In a basic attempt to develop the prophylactic and therapeutic measures on intestinal giantcystic disease of the Israel carp, C), prinks carpio nudum, the effects of physical and chemical factors on viability or survival of the spores of Thelchcnellus kiteuei were checked in vitro by means of extrusion test on the polar filament. When the fresh spores suspended with 0.45% and 0.9% scdium chloride solution and distilled water were laid at $5^{\circ}C$ and $28^{\circ}C$ for short terms, the extrusion rates increased until the 3rd day, meanwhile when son;e of them were suspended with Tyrode's solution at $-70^{\circ}C$ the rates increased gradually until the 8th day. Viabilities of the spores suspended with 0.9% saline and added antibiotics to the suspension at $5^{\circ}C$ for long terms lasted for 997 days and 1, 256 days (presumed values) at maximum, respectively. The spores suspended with distilled water at $28^{\circ}C$ for long terms survived 152.4 days, but the spores suspended with Tyrode's solution at $-70^{\circ}C$ for long terms showed almost the same viable pattern as early freezing stages up to 780 days. The spores suspended with Tyrode's solution, frozen at $-70^{\circ}C$ and thawed at $5^{\circ}C$, showed the highest rate of extrusion of the polar filament. In the case of frozen spores, the extrusion rates during heating tend to become higher in accordance with the increase of frozen period, and the critical points of 180 day-frozen spores to be killed were generally 78.5 hr. at $60^{\circ}C$, 23.4 hr. at $70^{\circ}C$, 189.1 min. at $80^{\circ}C$ or 10.5 min. at $90^{\circ}C$. The longer the spores were frozen, the more time was needed for the death of spores after thawing; 20 days-17.4 days, 100 days-33.2 days, and 400 days-37.8 days. The longer the spores were frozen, the more time was needed for the death of spores at a conventional when they were dried air drying condition, 540 days-23.5 days, 160 days-21.0 days, and 20 days-14.4 days. On the other hand, the longer the spores were frozen, the more spores were dead rapidly when they were irradiated with 10W UV-ray; 100 days-26.0 hr, 300 days-21.9 hr, and 540 days-13.9 hr. The time needed for killing 200 days-frozen spores by various disinfectants at 1, 000 ppd was 5.2 min. by calcium oxide, 10.4 min. by potassium permanganate, 27.8 min. by malachite green and 14.3 hr. by formalin. Transient inhibitory effects of the extrusion of the polar filament were observed by various antiprotozoal and antifungal agents in the descending order of ketoconazole. metronidasole and dapsone. The above results presume that full drying, followed by spraying CaO and maintaining sunny condition for a few days on the concrete bottoms of knish farm may be an effective method for the prevention of intestinal giant.cystic disease.

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The Ripening of Camembert Cheese Made with Mucor Miehei Rennet (Mucor Miehei 응유효소(凝乳酵素)로 제조(製造)한 Camembert Cheese의 숙성(熟成)에 관(關)한 연구(硏究))

  • Park, Mooh Il;Kim, Jong Woo
    • Korean Journal of Agricultural Science
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    • v.16 no.2
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    • pp.179-200
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    • 1989
  • Mucor miehei rennet(MR) was added as calf rennet(CR) substitutes in the fixed amounts of mixed rennets in making Camembert cheese. The conditions in the variations of chemical composition: water-soluble nitrogen, non-caseinic nitrogen, non-proteinic nitrogen, amino nitrogen, ammoniacal nitorgen, electrophoresis, molecular fractionation, mineral distribution, texture characterisitics, free amino acids and free fatty acids, were checked up with the sensory test and the chesse yields at each ripening period. The results obtained by investigating the utility of Mucor rennet were summarized as follows: 1. CR chesse, MR cheese and the mixed-rennet chesse failed to show any significant difference in their yields of 15%. 2. The contents of protein, fat and ash in MR cheese gave lower value than CR cheese did and with progress of ripening lactose decreased rapidly after 14 days of ripening. The difference among the rate of addition of mucor rennet was not recognized. 3. The WSN contents of 5 fresh sample chesse were from 14.7% to 17.3% and WSN increased from 39.7% to 41.0% with progress of ripening. After 21 days of ripening MR chesse had more WSN than CR cheese did. In NCN and ammoniacal nitrogen MR cheese showed higher value. 4. As the ripening progressed, MR chesse showed more cystein, phenylalanine and proline than CR chesse did but it failed to show any increase in aspartic acid, threonine and glutamic acid etc. 5. In the content of free fatty acid MR chesse showed higher value than CR cheese did and with the progress of ripening fatty acids increased from 8.36 mEq to 26.36 mEq but did not show any significant difference in the cheese types by the coagulant ratio. 6. Ca contents in the sample chesse were 0.238-0.27%, Mg 0.019-0.022%, Na 0.910-1.047%, and K 0.175-0.200%. The important non-sedimentable Ca in casein remained from 61 % to 77% without regard the ripening periods and added-rennets and Mg remained from 59.1% to 92.5% in non-sedimentable and water-soluble conditions. 7. In the fractionation of protein by ultrafilteration, MW> $5{\times}10^4$ decresed from 95% at the beginning period of ripening to 45% and MW< $10^4$ increased from 0.2% to 38% and definite caseinolysis was shown in all samples. 8. All the cheese showed to different electrophoretic patterns for the added-amounts of mucor rennet in the 14 days of ripenig. In the 28 days or ripening, MR cheese kept some bands on the patterns compared with CR cheese. 9. In vitro digestibility increased from 81.48-94.81 % to 94.47-98.61% but failed to show any significant difference in the cheese types by the coagulant ratio. 10. In hardness, MR cheese showed lower value compared with CR cheese as the ripening progressed. 11. The results of the sensory test failed to show any difference in flora rind, feelings in mouth and hands, deep structure, flavor and bitterness between CR Camembert cheese and MR Camembert chesse.

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A Study on the Consideration of the Locations of Gyeongju Oksan Gugok and Landscape Interpretation - Focusing on the Arbor of Lee, Jung-Eom's "Oksan Gugok" - (경주 옥산구곡(玉山九曲)의 위치비정과 경관해석 연구 - 이정엄의 「옥산구곡가」를 중심으로 -)

  • Peng, Hong-Xu;Kang, Tai-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.3
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    • pp.26-36
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    • 2018
  • This study aims to examine the characteristics of landscape through the analysis of location and the landscape of Gugok while also conducting the empirical study through the literature review, field study, and digital analysis of the Okgung Gugok. Oksan Gugok is a set of songs set in Ogsan Creek(玉山川)or Jagyese Creek(紫溪川, 紫玉山), which flows in front of the Oksan Memorial Hall(李彦迪), which is dedicated to the Lee Eong-jeok (李彦迪). We first ascertained the location and configuration of Oksan Gogok. Second, we confirmed the accurate location of Oksan Gogok by utilizing the digital topographic map of Oksan Gogok which was submitted by Google Earth Pro and Geographic Information Center as well as the length of the longitude of the gravel measured by the Trimble Juno SB GPS. Through the study of the literature and the field investigation, The results of the study are as follows. First, Yi Eonjeok was not a direct composer of Oksan Gugok, nor did he produce "Oksan Gugokha(Music)". Lee Ia-sung(李野淳), the ninth Youngest Son of Tweo-Kye, Hwang Lee, visited the "Oksan Gugokha" in the spring of 1823(Sunjo 23), which was the 270th years after the reign of Yi Eonjeok. At this time, receiving the proposal of Ian Sung, Lee Jung-eom(李鼎儼), Lee Jung-gi(李鼎基), and Lee Jung-byeong(李鼎秉), the descendants of Ian Sung set up a song and created Oksan Gugok Music. And the Essay of Oksan Travel Companions writted by Lee Jung-gi turns out being a crucial data to describe the situation when setting up the Ok-San Gugok. Second, In the majority of cases, Gogok Forest is a forest managed by a Confucian Scholar, not run by ordinary people. The creation of "Oksan Bugok Music" can be regarded as an expression of pride that the descendants of Yi Eonjeok and Lee Hwang, and next generation of several Confucian scholars had inherited traditional Neo-Confucian. Third, Lee Jung-eom's "Oksan Donghaengki" contains a detailed description of the "Oksan Gugokha" process and the process of creating a song. Fourth, We examined the location of one to nine Oksan songs again. In particular, eight songs and nine songs were located at irregular intervals, and eight songs were identified as $36^{\circ}01^{\prime}08.60^{{\prime}{\prime}}N$, $129^{\circ}09^{\prime}31.20^{{\prime}{\prime}}E$. Referring to the ancient kingdom of Taojam, the nine-stringed Sainam was unbiased as a lower rock where the two valleys of the East West congregate. The location was estimated at $36^{\circ}01^{\prime}19.79^{{\prime}{\prime}}N$, $129^{\circ}09^{\prime}30.26^{{\prime}{\prime}}E$. Fifth, The landscape elements and landscapes presented in Lee Jung-eom's "Oksan Gugokha" were divided into form, semantic and climatic elements. As a result, Lee Jung-eom's Cho Young-gwan was able to see the ideal of mountain water and the feeling of being idle in nature as well as the sense of freedom. Sixth, After examining the appearance of the elements and the frequency of the appearance of the landscape, 'water' and 'mountain' were the absolute factors that emphasized the original curved environment at the mouth of Lee Jung-eom. Therefore, there was gugokga can gauge the fresh ideas(神仙思想)and retreat ever(隱居思想). This inherent harmony between the landscape as well as through the mulah any ideas that one with nature and meditation, Confucian tube.

Biocontrol of Damping-Off(Rhizoctonia solani) in Cucumber by Trichoderma asperellum T-5 (Trichoderma asperellum T-5를 이용한 오이 모잘록병(Rhizoctonia solani)의 생물학적 제어)

  • Ryu, Ji-Yeon;Jin, Rong-De;Kim, Yong-Woong;Lee, Hyang-Burm;Kim, Kil-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.4
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    • pp.185-194
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    • 2006
  • A fungal strain of Trichoderma having strong chitinolytic activity was isolated from field soil enriched with crabshell for several years. Based on 5.8S rRNA, partial 18S, 28S rRNA genes, ITS1, ITS2 sequence analysis and morphological characteristics, the fungus was identified as Trichoderma asperellum and named as Trichoderma asperellum T-5 (TaT-5). The fungus released lytic enzymes such as chitinase and ${\beta}$-1, 3-glucanse, and produced six antifungal substances in chitin broth medium. To demonstrate the protective effect of TaT-5 against damping-off in cucumber plant caused by Rhizoctonia solani, TaT-5 culture broth (TA), chitin medium (CM) and distilled water (DW) were applied to each pot at 10 days after sowing, respectively. Then, the homogenized hyphae of R. solani were infected to each pot at 1 week after TaT-5 inoculation. During experimental period, fresh weight of shoot and root in cucumber plant more increased at TA treatment compared to other treatments. PR-proteins (${\beta}$-1, 3-glucanase and chitinase) activities in cucumber leaves markedly increased at CM and DW treatments, but the activity slightly increased and then decreased at TA treatment at 3 days after infection of R. solani. The activity of PR-proteins activities in cucumber roots at all treatments decreased with time where the degree of decrement was more alleviated at TA treatment than CM and DW. These results suggest that the lytic enzymes (chitinase and ${\beta}$-1, 3-glucanse) and antifungal substances produced by TaT-5 can reduce the pathogenic attack by R. solani in cucumber plants.

A Study on Changes of Physico-Chemical Properties of Plow Layer Soil and its Response of Tobacco Growth under Poly Ethylene Film Mulching Condition. -1. Effect of Poly Ethylene Film Mulch on Changes of Soil Temperature and Soil Moisture Content in the Rhizosphere (연초피복재배(煙草被覆栽培)에서 작토시(作土尸)의 이화학성변화(理化學性變化)와 연초생장반응(煙草生長反應)에 관(關)한 연구(硏究) -1. 피복조건(被覆條件)이 근권(根圈)의 토양온도(土壤溫度)와 수분변화(水分變化)에 미치는 영향(影響))

  • Hong, Soon-Dal;Lee, Yun-Hwan;Kim, Jai-Joung;Cho, Seong-Jin
    • Korean Journal of Soil Science and Fertilizer
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    • v.18 no.1
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    • pp.20-26
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    • 1985
  • Under the field condition mulched by polyethylene film, changes of the soil moisture content and soil temperature due to the meteorological influence, which have had a great effect upon productivity of upland - field crop, was investigated. The results obtained were as follows; 1. During the early growth stage from the first part of April to the last part of May, soil temperature at 15cm below the mulched surface of ridge (13:00) was about $5^{\circ}C$ higher than that of non-mulched plot. 20 days earlier than normal soil temperature reached up to $20^{\circ}C$ due to the mulching. The increasing of soil temperature resulted from poly ethylene film mulching had a similar tendency for the annual experiment of 3 years (1982-1984). 2. Changes of the soil moisture content in the plow layer during the growing season was remarkably less in the mulched plot than in the non-mulched plot due to suppression of evaporation by polyethylene film. 3. Soil moisture contents of the plots planted with tobacco was lower than those of the non-planted plots owing to the more transpiration induced by growing of the tobacco plant. As the results, it was refered that initial fresh weight of above ground part of tobacco that had an influence upon the consumption of soil moisture by the transpiration rather than evaporation was about 250g per plant. 4. At the appreciable amount of rainfall (for instance; 63.5mm), soil moisture content at middle place between plants in the plow layer of the mulched plot was not increased owing to the infiltration interruption by polyethylene film. 5. By the comparatively small amount of rainfall (e.g. 20mm) after the drought period, leaf water potential of the mulched plot was not increased as much as that of the non-mulched plot owing to the less moisture content of soil resulted from interruption of rainfall.

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