• Korean journal of applied entomology
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• v.34 no.3
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• pp.266-277
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• 1995

The adult brown planthopper possesses tow oval shaped compound eyes which, on their ventral borders, curve around the base of the antennae. Compound eye of the adult brown planthopper is recognised apposition eye which each ommatidium is optically isolated from it surroundings, the rhabdoms receiving light only from their own corneal lens. Each ommatidium possesses its own dioptric apparatus formed from the cuticular cornea and an underlying crystalline cone. The retinula cells lying immediately beneath the crystalline cone have their individual rhabdomeres tightly opposed to form one central, closed rhbdom. The rhabdom stretches from the spex of the crystalline cone nearly to the basement membrane and is approximately 110~120 $\mu\textrm{m}$ in length. The crystalline cone is surrounded by a pair of primary pigment cells an these in turn are surrounded by accessory pigment cells. Accessory pigment cells extend beyond the crystalline cone surrounding the retinular cells in the distal region of the eye. The crystalline cone is surrounded by the distal-most regions of the retinula cells show the presence of seven cells and sections taken proximally in the last quarter of the omatidium before the basement membrane is reached, reveal the presence of a small, eighth retinula cell which also contributes to the central rhabdom. Each ommatidium has a central rhabdom formed from the modified inner border of all of the retinula cells. Th rhabdom consists of micrvilli arising from the inner wall of each retinula cell. In cross section th microvilli exhibit a characteristic honeycomb appearance. Pigment cells comprise the primary pigment cells enveloping the crystalline cone, the accessory pigment cells extending from the inner surface of the comea to the basement membrane and the small pigment cells of the basement membrane.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.233-236
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• 2008

A positive selectable marker system was adapted for transformation of mature embryo-derived calli of Indica rice (Oryza sativa L.) utilizing the PMI gene encoding for phosphomannose-isomerase that converts mannose-6-phosphate to fructose-6-phosphate. The transformed cells grew on medium supplemented with 3% mannose as carbon source and calli were selected on media containing various concentrations of mannose. Molecular analyses showed that the transformed plants contained the PMI gene. The results indicate that the mannose selection system can be used for Agrobacterium-mediated transformation of mature embryo in rice to substitute the use of conventional selectable markers in genetic transformation.

• Journal of Biosystems Engineering
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• v.24 no.1
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• pp.9-18
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• 1999

This study was performed to investigate the optimum microalgal culture conditions using flask culture and to find the feasibility of using the flue gas of the rice husk incinerator for cultivating the microalgae. The optimum initial pH of media was 4.5 for the microalgae culture, and the intermittently illuminated culture was more effective than the continuous illuminated culture. Thus, the balance between photosynthesis and formative metabolism must be considered thoroughly to cultivate microalgal cells. The optimum CO2 concentrations were in the range of 7 to 10%, and the optimum temperature was about 35$^{\circ}C$ in both the daytime and the nighttime for the culture. When flue gas of the rice husk incinerator was applied to the microalgae culture using stirred photobioreactor, the dry cell weight was 0.026 g dry biomass/hr$.$l. The results obtained in experiments indicated that the flue gas was effective for microalgae culture without any limitations.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.379-386
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• 2004

Jeung-Pyun is a traditional Korean fermented rice cake leavened by yeast. To develop a functional Jeung-Pyun, mulberry leaf(ML) were added to the rice at the levels of 0, 2, 4, 6, 8%, respectively. Physicochemical, sensory, texture and surface characteristics of Jeung-Pyun were examined. The specific volumes of all the Jeung-Pyun's with ML were significantly lower than that of control(0% ML) and 4% ML sample showed the highest volume among them. The pH of ML Jeung-Pyun batters decreased with fermentation time. Overall quality of Jeung-Pyun with ML obtained lower value than the control. Among the texture properties measured with rheometer, hardness, cohesiveness, gumminess and brittleness of ML Jeung-Pyun decreased according to the amount ML added and springiness was not significantly different. The surface structure by SEM showed that Jeung-Pyun added with 4% ML had the largest and the most uniform air cells. In conclusion, the most acceptable concentrations of ML on the basis of overall quality in sensory evaluation and physicochemical characteristics were 2% or 4%.

• Korean Journal of Breeding Science
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• v.43 no.4
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• pp.260-264
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• 2011

Leaf structure is one of the important agronomic traits. A rolled leaf mutant was induced from an ethyl methane sulfonate (EMS)-treated japonica rice, 'Koshihikari'. The rolled leaf mutant showed phenotypes of reduced leaf width and leaf rolling. In addition, several abnormal morphological characteristics were observed, including dwarfism, defected panicle, delayed germination, and lower seed-setting. Microscopic analysis revealed that the number of small veins was decreased and the sizes of adaxial bulliform cells were reduced in the mutant leaves. The genetic study with two $F_2$ populations from the crosses of the rolled leaf mutant with 'Koshihikari' and Milyang23 suggested that the mutant phenotype might be controlled by a single dominant gene.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.221-228
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• 2001

This study was carried out to investigate the effect of germination condition and drying temperature on growth and physicochemical properties of brown rice. Three brown rice seeds of Ilpumbyeo, Dasanbyeo and Heugjinjubyeo were stored at room temperature for six weeks to test the time-sequence germination viability. Relatively stable germination ratio was maintained until 2 weeks after storage. However, 3 weeks after storage, germination ratio of brown rice seeds started to decrease rapidly and their germination ratio was lower than 80%. For this reason, brown rice was recommended for seeding within 2 weeks after hulling. During the initial 5 days, germination ratio of 24 hours pre-soaking brown rice was higher about 2-3% than that of non-soaking brown rice. The $25^{\circ}C$ was considered as the most favorable temperature for brown rice germination, because of the high germination ratio and desirable coleoptile growth of the brown rice, and little seed rotting symptoms. The scanning electron micrographs showed the structural differences between hot-air dried and freeze dried germinated-brown rice kernel. In the freeze dried germinated-brown rice, seed coat (pericarp, tegmen and aleurone layer) was mechanically disrupted from the endosperm, and many cleavages were observed among starch storing cells and starch granules. The endosperm of freeze-dried brown rice kernels formed the sponge-like structures and showed the fragile traits. For this reason, hot-air drying is considered as more suitable method than freeze drying for germinated-brown rice. The crude protein and amylose contents were slightly changed, but there were no significant differences during the germination period. Crude fiber content was decreased, but crude Int and total amino acid contents were increased as seeding days increased. A rapid increase in $\alpha$-amylase activities of germinating brown rice was observed at S days after seeding, and $\alpha$-amylase activities were decreased from 8 days after seeding. Total free sugar contents were decreased during the germination period. There was continuous decline in the contents of sucrose and glucose until 8 days after seeding, but fructose and maltose content were gradually increased from the 5 days after seeding.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1407-1414
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• 2014

Physicochemical properties of rice-based expanded snacks extruded with rice flour, high amylose starch, and isolated soy protein were investigated using a twin-screw extruder. The ingredients were extruded at various feed moisture contents (19~23%) and screw speeds (200~400 rpm) at a constant feed rate (43.4 kg/hr). Bulk density and apparent density of rice snacks were 0.06~0.21, and 0.55~0.65 respectively. Bulk density, apparent density, water absorption index, and breaking strength of rice snacks increased with increasing feed moisture content and decreasing screw speed. However, expansion and water solubility index of rice snacks increased with decreasing feed moisture content and increasing screw speed. Hunter's color L values of rice snacks was lower with increasing screw speed at feed moisture contents of 19% and 21%, but was not significantly different from a feed moisture content of 23%. On the other hand, a and b values of rice snacks were higher with increasing screw speed a feed moisture content of 19%. X-ray diffraction intensity of rice snacks decreased with decreasing feed moisture content and increasing screw speed. X-ray diffraction of rice snacks was V-type at feed moisture contents of 19% and 21% and screw speeds of 300, and 400 rpm. In the microstructure of the cross section of rice snacks, air cells in rice snacks were not well formed, and cell walls were thicker with increasing feed moisture content and decreasing screw speed.

• BMB Reports
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• v.51 no.11
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• pp.578-583
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• 2018

Telomeres are specialized nucleoprotein complexes that function to protect eukaryotic chromosomes from recombination and erosion. Several telomere binding proteins (TBPs) have been characterized in higher plants, but their detailed in vivo functions at the plant level are largely unknown. In this study, we identified and characterized OsTRFL1 (Oryza sativa Telomere Repeat-binding Factor Like 1) in rice, a monocot model crop. Although OsTRFL1 did not directly bind to telomere repeats $(TTTAGGG){_4}$ in vitro, it was associated with telomeric sequences in planta. OsTRFL1 interacted with rice TBPs, such as OsTRBF1 and RTBP1, in yeast and plant cells as well as in vitro. Thus, it seems likely that the association of OsTRFL1 with other TBPs enables OsTRFL1 to bind to telomeres indirectly. T-DNA inserted OsTRFL1 knock-out mutant rice plants displayed significantly longer telomeres (6-25 kb) than those (5-12 kb) in wild-type plants, indicating that OsTRFL1 is a negative factor for telomere lengthening. The reduced levels of OsTRFL1 caused serious developmental defects in both vegetative and reproductive organs of rice plants. These results suggest that OsTRFL1 is an essential factor for the proper maintenance of telomeres and normal development of rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.1-6
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• 2006

Rice is the most important crop in Korea and its annual production of 5.2 million ton is followed by over 0.5 million ton of bran as by-products of milling process. Although rice bran contains various nutritious and pharmaceutical compounds, rice brans are rarely utilized as functional food sources in Korea. In recent, tocotrienols are well known having distinctive pharmaceutical effectiveness. So tocotrienols extracted from rice bran oil were evaluated about Pharmaceutical function. The $IC_{50}$ of tocotrienols products against liver cancer, HepG2 cells were $149mg\;mL^{-1}$, indicating anticancer activity of final products. By animal feeding tests, the final products containing tocotrienols did not induce any toxicity signs in mortality, Incidence of clinical signs, body weight, etc. after a single oral administration, which proved safety of the tocotrienol products. In conclusion, tocotrienol extracted from rice bran has pharmaceutical activity without any toxic effects, which is also suggested tocotrienol products may be a good fortifying nutrition far the health and medical care.

• Molecules and Cells
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• v.37 no.2
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• pp.149-160
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• 2014

Plant breeders have focused on improving plant architecture as an effective means to increase crop yield. Here, we identify the main-effect quantitative trait loci (QTLs) for plant shape-related traits in rice (Oryza sativa) and find candidate genes by applying whole genome re-sequencing of two parental cultivars using next-generation sequencing. To identify QTLs influencing plant shape, we analyzed six traits: plant height, tiller number, panicle diameter, panicle length, flag leaf length, and flag leaf width. We performed QTL analysis with 178 $F_7$ recombinant inbred lines (RILs) from a cross of japonica rice line 'SNU-SG1' and indica rice line 'Milyang23'. Using 131 molecular markers, including 28 insertion/deletion markers, we identified 11 main- and 16 minor-effect QTLs for the six traits with a threshold LOD value > 2.8. Our sequence analysis identified fifty-four candidate genes for the main-effect QTLs. By further comparison of coding sequences and meta-expression profiles between japonica and indica rice varieties, we finally chose 15 strong candidate genes for the 11 main-effect QTLs. Our study shows that the whole-genome sequence data substantially enhanced the efficiency of polymorphic marker development for QTL fine-mapping and the identification of possible candidate genes. This yields useful genetic resources for breeding high-yielding rice cultivars with improved plant architecture.