• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.26-31
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• 1978

The objective of the present study was to investigate the effect of nicotine-contaminated mulberry-leaf, which was grown in the vicinity of tobacco drying plant (TDP), on cocoon crop. Mulberry-leaf harvested from the field at Sericultural Experiment Station (SES), Suweon, Korea, was used as control, supposedly nicotine-free leaf. Leaf harvested from the field in the distances of 30-50m, 300-400m and 700-800m from TDP was fed during the whole larval stage of the silkworm at. SES. The effect of leaf in each treatment level on the quantitative characters of the silkworm was summarized as follows; 1. Larval duration from 4th instar on was significantly longer in the TDP-leaf treatments than for the control. 2. Duration of matured silkworm appearance became longer as the distance of the mulberry-field from TDP got shorter, because the larval duration and growth of the silkworm were not uniform in the TDP-leaf treatments. 3. Mortality rates during the late larval, cocoon spinning, and pupal stages were highest for the 30-50m leaf, especially mortality rates during the late larval and pupal stage were serious. 4. Pupation rate was lowest for the 30-50m leaf and those for the 300-400m and the 700-800m leaf were not significantly different from that of the control. 5. Nicotine damage to cocoon weight and cocoon shell weight was significant in each TDP-leaf level. Cocoon shell ratio was reduced at the same extent in each level, compared with the control. 6. The ratio among cocoon-classes was significantly different between treatments, compared with best-cocoon ratio of 87.1% for the control. Cocoons were not uniform for the 30-50m leaf, and those for the 300-400m and the 700-800m leaf were as almost uniform as those for the control. 7. Loss of fresh cocoon yield became greater as the distance of the mulberry-field from the TDP-got shorter. In conclusion, the critical distance of mulberry-field, which influences larval health, cocoon quality and yield, appeared to be 800m from the TDP. Such other factors as wind direction and topographic location may be involved in the critical distance. 8. From the present experiment, we could obtain only the effect of nicotine on the silkworm through digestive system, since the silkworm was raised at SES in Suweon. If the silkworm.. were raised in the vicinity of the TDP, poison effect of nicotine on the silkworm could beo expected through exoskeleton and tracheal system as well as through digestive system.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.448-452
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• 2015

'Seeberry' is a short-day $F_1$ hybrid strawberry for seed propagation, that was released by the Protected Horticulture Experiment Station (RDA, Republic of Korea) in 2013. Inbred lines derived from domestic germplasms and selected varieties were used to develop this cultivar. 'Seeberry' originated from a cross of two inbred lines: a male parent 'Wongyo 3115' with high firmness and a female parent 'Wongyo 3116' with excellent fruit shape and high yield. 'Seeberry' cultivar should be grown with a crown diameter of over 10 mm to reveal its unique characteristics. 'Seeberry' has an upright plant shape with elliptic leaves, 12-15 flowers per cluster, vigorless growth habit, and average flower bud differentiation compared to vegetatively propagated cultivars. Fruits of 'Seeberry' are conical, having light skin color and approximately 15-16 g in average weight. Yield of this cultivar is about 92% lower than that of 'Akihime', but 'Seeberry' has excellent taste, sugar content of $9.7^{\circ}Bx$, acidity of 0.6%, and good texture. With regard to disease and pest resistance, 'Seeberry' is sensitive to powdery mildew, aphids, and the two-spotted spider mite, and is resistant to anthracnose.

• Animal Systematics, Evolution and Diversity
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• v.5 no.1
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• pp.77-88
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• 1989

Genetic and morphometric comparison between two species of the genus Agkistrodon were performed to estimate the degree of genic variation and to clarify the taxonomic status of Cheju population, a suspected hybrid form between A. blomhoffii brevicaudus and A u ussuriensis. A sum of 147 specimens representing six populations of A.b. brevicaudus and two populations of A ussuriensis was used in this study. Out of the 21 loci examined, 5 loci (Adh, Ldh-2, Mdh-2, Mpi, Pgi) were monomorphic with identical mobility in both species. O Other Sioci (Aco, Gp, Fum, [po and Xdh in A b. brevicaudus; Est, Got-l, Gp, Mdh-l and 6Pgd in A ussuriensis) were highly poplymorphic. The degree of genic variation of Ab. b brevicaudus and A ussuriensis was A=1.SS, P=42.1%, HD=0.096, HG=O.l1S, and A= 1.4S, P = 31.6%, HD=0.117, HG =0.121, repectively. These values are twofold higher t than those of other reptilian species reported (Selander, 1976) including Korean species of Rhabdophis tigrina and Elaphe dione (Paik and Yang, 1986, 1987). The average values of t the genetic similarities among six populations of A b. brevicaudus and two populations of A ussuriensis were S=0.919 and S=0.962, respectively, whereas the value between species was S = 0.662. Presumed divergent time estimate (Nei, 1975) of these two species was about 1 1.8 million years ago. The analysis of the geographic variations of various morphological c characters was based on Gloyd’s criteria (Gloyd, 1972). Coloration of tongue and tail tip, t the number of ventral scales, and the number of subcaudal scales are good diagnostic c characters to identify these two species. The pattern of cross band is, however, highly variable within and between populations of both species. No hybrid was detected and the s suspected hybrid form of Cheju population falls within the range of A. ussuriensis in the g genetic and morphometric analyses.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.77-80
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• 2005

This study was conducted to determine effects of cutting date, cutting position, and node number on rooting of Rubus buergeri Miquel. Apical, medial, and basal parts of the vines emerged in 2002 were cut on June 26, August 2, and September 4, in 2002. Vine pieces with one to four nodes taken from the medial parts of the vines were also cut on July 10. The greatest rooting (69.6%) occurred in cuttings taken on August 2. Cutting taken on June 26 had the longest roots (23.1 cm). Rooting and new shoot growth markedly decreased at September 4 cutting. The greatest rooting (55.4%) occurred in cuttings taken from medial part of the vines and followed by apical parts (45.6%), and basal parts (25.4%). The other traits were not significantly affected by cutting position. Rooting percentage and percent new shoot growth were not significantly affected by node number, but root number and root dry weight per cutting, and new shoot growth increased with node number.

• Journal of Wetlands Research
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• v.13 no.3
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• pp.603-611
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• 2011

In order to enhance cutting efficiency of reed culms, we had assessed diverse methodology in cutting and applied better conditions among them into three vigorous eco-types of common reed. From the results, differences in a eco-type, a sampling area in reed population and substrata affected the shoot emergence slightly. On the other hand, differences in a type of burying culms and a burying part among whole culm affected shoot emergence strongly. Our results suggest that not only methodological condition but also appropriate kind of eco-types must be considered in using reed culms for better cutting. In addition that, sampling timing according to the geological and climatic condition of certain area should be considered for better cutting efficiency as well. We also recommend that the sampling area such as expanding area in a population, burying a middle part of the culm, substratum such as well-ventilated sand and vertical burying method for better cutting efficiency. Lastly, for more enhancement of cutting efficiency of reed culms, potential damages by blight and harmful insects such like aphids should be concerned very carefully.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.205-212
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• 1999

This study was carried out to examine the effect of polyethylene film color and removing time of the mulching film in yacon (Polymnia sonchiiolia Poepp. & Endl.). The plant height on nonmulching was smaller about 10 cm or larger with 112cm than on other mulches ranged with $134{\sim}139$ cm at harvesting, and other characters examined were similar to that of plant height. The weight of tuberous root per plant was heavier on mulches ranged with $0.79{\sim}0.91$ kg than on non-mulching with 0.61 kg. Among the kind of mulches, plant height was the tallest with 139 cm in combination and declined in order of transparent, green and black polyethylene films. Yields among colored polyethylene films were the heaviest with 0.91 kg per plant in combination, 0.88 kg in black and 0.84 kg in green. In growth and yield full mulching untill harvesting was more effective than the other removed mulching treatments. It was effected on growth promotion at early growth stage, soil temperature and water preservation.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.58-72
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• 1985

A histopathological study was carried out on the duodenum of mice and rats experimentally infected by F. seoulensis. Each mouse was infected with 500 metacercariae and killed after 1, 2, 3 days, 1 and 2 weeks from infection. Each rat was given 1, 000 metacercariae and was examined after 1, 2 and 4 weeks from infection. The duodenal tissue sections of mice and rats were stained with hematoxylin eosin, and PAS stained for the rats of 1 week group. The pathological findings are summarized as below. 1. There were no differences in mucosal findings between the mice and the rats, and between the location of duodenum, 1 and 5 em distal to the pylorus. 2. Each worm embraced a villus exclusively with its foliate fore body which was inserted into the intervillous spaces. The fluke pinched villous epithelia using its oral and ventral suckers. The tribocytic organ destroyed the villous epithelia deeply up to the stroma after 3 days from infection. 3. Apparent villous changes were observed in the mice after 3 days from infection. Villous changes were shortening, widening, blunting or fusion. The villous stroma showed edema, microscopic hemorrhage, capillary congestion, dilatation of lymphatics and inflammatory cell infiltration. The cells were lymphocytes, plasma cells, eosinophils and giant cells. Rarely submucosal and trans:nural inflammation was encountered.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.97-105
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• 2010

This study focuses on investigating morphological characteristics and variations level in native zoysiagrasses from costal regions and islands in South Korea. In addition, this were collected to conserve germplasm for the breeding of zoysiagrass. One hundred fifty-nine of native zoysiagrasses were collected from 16 different cities and districts. There were morphological evaluations, including plant height, leaf width, leaf length, leaf angle, seed length(SL), seed width(SW), SL/SW ratio and number of seed per spike in native zoysiagrasses. Type of Z. japonica, Z. sinica, Z. macrostachya and Z. matrella showed significant variations in plant height, leaf length, leaf angle and number of seed per spike depending on where they were collected from. On the other hand, little variation were found in leaf width, seed length, seed width and SL/SW ratio. We have discovered a variety of variations among the investigated traits in hybrid zoysiagrass. These results can be used as basic information for development of zoysiagrass breeding.

• Parasites, Hosts and Diseases
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• v.34 no.2
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• pp.135-142
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• 1996

Antigenic domain of jai or surface protein (p30) of Toxoplosmc Sondii was analyzed after polymerase chain reaction (PCR) of its gene fragments. Hydrophilic or hydrophobic moiety of amino acid sequences were expressed as glutathione S-transferase (G57) fusion proteins. Fragments of p30 gene were as follows: 737, total p30 open reading frame (ORF) ; S28, total ORF excluding N-terminal signal sequence and C-terminal hydrophobic sequence; Al9, N-terminal 2/3 parts of A28; A19, N-terminal 2/3 of S28; P9, C-terminal 2/3 part of S28; Z9. middle 1/3 of S28; and 29, C-terminal 1/3 of S28. respectively. Primer of each fragment was synthesized to include clamp sequence of EcoR I restriction site. PCR amplified DNA was inserted info GST (26 kDa) expression vector, PGEX-47-1 to transform into Escheri,hia coei (.JM105 strain). G57 fusion proteins were expressed with IPTG induction as 63. 54, 45, 45, 35, 36. and 35 kDa proteins measured by SDS-PAGE. Each fusion protein was confirmed with G57 detection kit. Western blot analysis with the serum of a toxoplasmosis patient revealed antigenicity in proteins expressed by T37. S28, and Al9 but not those by Pl8. X9, Y10, and Z9. Antigenicity of p30 seems to be located either in N-terminal 115 part in the presence of middle 1/3 part or in the oligopeptides between margins of the first and second 1/3 parts.

• Journal of Life Science
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• v.14 no.5
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• pp.868-873
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• 2004

The efficient fermentative production of L-threonine fermentation was achieved by using Escherichia coli MT201, transformed a plasmid carrying pyruvate carboxylase gene. It is an attempt to supply oxaloacetate to the L-threonine biosynthetic pathway. In order to improve the L-threonine productivity of E. coli MT201, a plasmid pPYC which is an expression vector of the pyruvate carboxylase gene of Coryne-bacterium glutamicum, was introduced. When E. coli MT/pPYC was incubated with medium containing only glucose as a carbon source, both the cell growth and L-threonine production were reduced, compared to the results from fermentation of E. coli MT201. In order to circumvent this effect, we attempted the addition of a mixed carbon source, composed of glucose and sodium citrate at a ratio of 1.5:3.5. It was shown that L-threonine production and cell growth (OD660) with E. coli MT/pPYC reached up to 75.7 g/l and 48, respectively, at incubation for 75 hr under fed-batch fermentation conditions. It is assumed that overproduction of L-threonine by anaplerotic pathway leads unbalance of TCA cycle and sodium citrate might playa role to recover normal TCA cycle.