• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.16-23
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• 1987

This experiment was conducted to determine the isozymic differences between normal maize and maize inbreds of multiple ears and tillers (MET). Two maize inbreds Euisung, Iri and their hybrid having tillers and multiple ears were compared with normal maize. With usual electrophoresis using 6% polyacrylamide gel, peroxidase and esterase enzymes were studied. Matured leaf, culm, leaf sheath, root and young ear tissues showed different isozymic patterns between METs and normal maize in peroxidase. The Euisung inbred grown for 7 days under dark condition showed typical peroxidase. bands compared with checks in the tissues of coleoptile and stele. Better observation of isozymic bands was made during early part of maize growth. Parental inbreds showed more active and apparent band differences than their hybrids in esterase. Bands for esterase were also apparently different in the stele, coleoptile and young ear tissues of the METs and the checks. The maize lines infected with black streaked dwarf virus showed obvious differences in peroxidase and esterase isozymes.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.6
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• pp.800-805
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• 2012

Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase) and its wild type (WT) were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p<0.01) and a lower leaf blade proportion (25.21% vs 32.14%, p<0.01) than WT. Chemical composition analysis showed that BM rice straw was significantly (p<0.01) higher in CP (crude protein), hemicellulose and acid insoluble ash (AIA) contents, but lower in dry matter (DM), acid detergent fiber (ADFom) and cellulose contents when compared to WT. No significant difference (p>0.05) was detected in neutral detergent fiber (NDFom) and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05). The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05), but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.431-436
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• 1994

The objective of experiment was to investigate the effects of sowing dates on forage yield and growth characteristics of rye in paddy field cultivation in midwest region of Korea. The field experiment treated with 5 levels of sowing dates was carried out at Yesan from october 1990 to june 1991. The field emergence rate and winter survival rate were decreased with delay in sowing dates by the days from sowing to emergence were took a long period of time. The crop growth rate were increased with early in sowing date. The fresh and dry weight of rye were increased with early in sowing date, but there was no significant differences between sowing date from Oct. 5 to Oct. 25. The highest fresh yield was obtained at flowering stage and the highest dry yield was obtained at milky stage. The ratio of leaf blade and leaf sheath in rye plant were decreased with earlier sowing date and delayed harvest, but the ratio of stem and inflorescence was vice versa.

• Research in Plant Disease
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• v.19 no.3
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• pp.177-182
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• 2013

Resvestrol has been known to inhibit bacterial and fungal growth in vitro, and can be accumulated in plant to concentrations necessary to inhibit microbial pathogens. Hence, stilbene synthase gene has been used to transform to synthesize resveratrol in heterologous plant species to enhance resistance against pathogens. In the present study, we investigated the antimicrobial activities of resveratrol and piceid to bacterial and fungal pathogens, which causing severe damages to rice plants. In addition, disease resistance was compared between transgenic rice varieties, Iksan 515 and Iksan 526 transformed with stlibene synthase gene and non-transgenic rice varieties, Dongjin and Nampyeong. Minimum inhibitory concentration of resveratrol for Burkolderia glumae was 437.5 ${\mu}M$, and the mycelial growth of Biplaris oryzae was slightly inhibited at concentration of 10 ${\mu}M$. However, other bacterial and fungal pathogens are not inhibited by resveratrol and piceid. The expression of the stilbene synthase gene in Iksan 515 and Iksan 526 did not significantly enhanced resistance against bacterial grain rot, bacterial leaf blight, sheath blight, and leaf blight. This study is the first report on the effect of resveratrol and piceid against pathogens of rice plant, and changes of disease resistance of transgenic rice plants transformed with stilbene synthase gene.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.237-242
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• 2008

A liguleless mutant, which showed complete loss of lamina joint region at the junction between leaf blade and leaf sheath, was isolated from a Ds insertional mutants derived from the source cultivar, Dongjin. This mutant could not affect other developmental patterns like phyllotaxis. Southern blot analysis, using GUS as a probe, revealed that the liguleless mutant contained three Ds copies transposed in the rice genome. Among the four genomic sequences flanking the Ds, one was mapped in the intergenic region (31661640 - 31661759), and the other two predicted a protein kinase domain (12098980 - 12098667) as an original insertion site within a starter line used for massive production of Ds insertional mutant lines. Another predicted and inserted in first exon of liguleless 1 protein (OsLG1) that was mapped in coding region (LOC_Os04g56170) of chromosome 4. RT-PCR revealed that the OsLG1 gene was not expressed liguleless mutants. Structure analysis of OsLG1 protein revealed that it predicted transcription factor with a highly conserved SBP domain consisting of 79 amino acids that overlapped a nuclear localization signal (NLS). RT-PCR revealed that OsLG1 is mainly expressed in vegetative organs.

• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.161-170
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• 2008

Recently irregular dark-colored patches were found on the Kentucky teeing ground in a golf course in Gyunggi providence. Interestingly, blue-green algae from the leaf tissue sample containing black spot-stained symptoms were largely observed through microscopic study. In general, algae present on the upper soil surface or in the upper layer of root zone form dark brown layers of scum or crust, which invoked harmful effects to turf growth such as poor drainage, inhibition of new root development. In this observation, unlike the algae were sometime found in senescing leaves on contacted soil in July and August, the blue-green algae were detected within black spot-stained Kentucky bluegrass leaf tissues including leaf blade, ligule, auriclea as well as leaf sheath. The blue-green algae were also detected on the leaf and stem tissue adjacent to the symptomatic leaf tissues. Two species of blue-green algae, Phomidium and Oscillatoria, were greatly observed. Oscillatoria species was more commonly notified in all samples. In addition, the two species were found on a putting green showing yellow spot disease at another golf course in Gyunggi providence. The data from chemical control assay revealed that chemicals such as propiconazole, iprodione, and azoxystrobin decreased blue-green algae population and leaf spots, which finally resulted in enhanced leaf quality. All taken together, we strongly suggested that the disease-like phenomenon by blue-green algae might be very closely mediated with infection/translocation process in relation with turfgrass. It indicates that blue-green algae in turf management may play an adverse role as a secondary barrier as well as a pathogenic agent. This report may be helpful for superintendents to recognize and understand the fact that algae control should be provided more cautiously and seriously than we did previously in upcoming golf course management.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.122-131
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• 2005

For development of new agrochemical fungicide, syntheses of pyrrolo[2,1-b]thiazole carboxanilide derivatives 9 and antifungal screening against 6 kinds of plant pathogens were carried out. Functionalization of carboxylic acid on C-2 into carboxanilide in the pyrrolo[2,1-b]thiazole resulted in new 20 candidates, in which are ${\alpha},{\beta}$-unsaturated carboxanilide and methyl groups that are in cis relationship. Treatment of acetoxy-1,4-thiazin with magnesium in refluxing methanol gave pyrrolo[2,1-b]thiazole ethyl ester 4 in higher yield than that of the previous report. Hydrolysis of this compound afforded the corresponding acid 5, which reacted with aniline derivatives in the presence of coupling reagent, DIC to give pyrrolo[2,1-b]thiazole carboxanilides 9. As the result of in vivo antifungal assay of 9 against rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, some compounds showed selectively antifungal activities against the rice blast and wheat leaf rust.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.1
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• pp.41-47
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• 2009

Since significant losses of seagrass coverage have been reported from many parts of the world, numerous restoration projects through seagrass transplantation have been attempted worldwide. Different survival rates and establishment time of transplants have been reported depending on transplanting time and methods. The staple method, which is direct seagrass planting method using staples to anchor seagrass transplants on the sediments, have been widely adopted in seagrass transplanting because this method achieves high survival rates in various sediment environments. To assess the morphological plasticity and the growth characteristics of transplants, we transplanted eelgrass, Zostera marina in December 2004 using the staple method. Shoot density, morphological characteristics and leaf productivities of the transplanted shoots and shoots of natural eelgrass beds in the vicinity of the transplanting site and environmental parameters in the planting site were monitored for about 1 year postplanting monthly. Transplant shoot density increased without initial decline, while leaf width and sheath length of transplants decreased after transplanting. Leaf productivities per shoot of transplants also considerably lower than those of natural shoots for the first 3 months post-transplanting. Shoot density, morphological characteristics and leaf productivity per area of transplants became similar to those of natural population about 1 year after transplanting. Although eelgrass transplants might have experienced some transplanting stress during the early stage of the transplantation, transplants appeared to adapt well to new environments of the transplanting site.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.37-43
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• 1992

Typhula incarnata grew over a temperature range of -5 to $20^{\circ}C$ with maximum growth at 10 to $15^{\circ}C$. Sclerotial production for T. incarnata was greatest at the higher temperature. Maximum mycelial growth of this pathogen occurred from pH 5.4 to 6.2. When carbon sources were added to a basal salt medium (Czapek's dox agar) at 5 g carbon sources/l, inulin, soluble starch, galactose, glucose, mannose, manitol, sucrose, maltose, cellobirose, trehalose, raffinose, and dextrin supported growth better than other carbon sources did. Of the twenty-three nitrogen sources tested, glycine, serine, ammonium sulfate, asparagine, asparatic acid, and ${\beta}-alanine$ were the most favorable for mycelial growth of T. incarnata. Cystine and cysteine were poor nitrogen sources. Ammonium salt of nitrogen sources supported growth better than nitrate salt of nitrogen sources. Potato dextrose agar, oat meal agar, and V-8 juice agar were the most favorable for mycelial growth and sclerotial formation. Appropriate addition of pepton to PDA decreased mycelial dry weight, but sucrose supported good growth of T. incarnata. Percent viable sclerotia of T. incarnate buried in bentgrass soil decreased from 2 months after treatment remarkably. Trichoderma riride and bacteria were isolated from non-germinated sclerotia. Live orchard grass leaf pieces within the soil were colonized by T. incarnata better than sterile and unsterile dead leaf pieces at $0^{\circ}C$. Saprophytic ability of T. incarnate on sterile leaf sheath occurred better at $0^{\circ}C$ than at $10^{\circ}C$. Saprophytic microflora consisting of Cladosporium sp., Fusarium sp., Mucor sp., Pythium sp., and unidentified fungi were the competitors for the sterilized and unsterilized substrate, but their colonization was not find on live leaf sheath buried in the soil at $0^{\circ}C$. In the effect of fungicides to Typhula snow mold disease of creeping bentgrass, mixture of polyoxin and thiram was the most effective, followed by iprodione, mixture of iprodione and oxine copper, thiophanate-methyl, myclobutanil, and tolclofos-methyl.

• Korean Journal of Weed Science
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• v.14 no.2
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• pp.128-143
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• 1994

At 5 DAS/T, leaf primordia of rice stems that were grown under dry condition in transverse sections were strongly stained while those under water condition had many aerenchyma cells well developed. On the other hand, leaf primordia and large air spaces in stem of transplanted rice were well developed. Rice in leaf anatomy had small and fine epidermal cells, chlorophyllous mesophylls, and bulliform cells but had no chlorophyllous vascular bundle sheath cells, while barnyardgrass leaf had large, rough and irregularly arranged epidermal cells, chlorophyllous vascular bundle sheath cells, and non-bulliform cells but had no chlorophyllous mesophylls. Epidermal cells of transplanted rice, however, were well developed, differentiated and sclerified. Cross sections of rice root under dry condition showed cell contents, regularly arranged cells, non-intercellular spaces and non-aerenchyma while under water condition had well-developed intercellular spaces, aerenchyma cells, small and densely arranged epidermis, sclerified exodermis and sclerenchyma cells. But root anatomy of transplanted rice consisted of finely, regularly arranged epidermis, well-developed intercellular spaces and nucleous cells.