• Journal of Biosystems Engineering
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• v.25 no.2
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• pp.97-106
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• 2000

To develop the grain moisture meter using microwave free space transmission technique, a 10.5GHz microwave signal with the power of 11mW generated by an oscillar with a dielectric resonator is transmitted to an isolator and radiated from a transmitting $2{\times}2$ microstrip patch array antenna into the sample holder filled with the 12 to 26%w.b. of Korean Hwawung paddy rice. the microwave signal, attenuated through the grain with moisture, is collected by a receiving $2{\times}2$ microstrip patch array antenna and detected using a Shottky diode with excellent high frequency characteristic. A pair of light and simple microstrip patch array antenna for measurement of grain moisture content is designed and implemented on atenflon substrate with trleative dielectric constant of 2.6 and thickness of 0.54 by using Ensemble ver. 4.02 software. The aperture of microstrip patch arrays is 41 mm width and 24mm high. The characteristics of microstrip patch antenna such as grain. return loss, and bandwidth are 11.35dBi, -38dB and 0.35GHz($50^{\circ}$ at far-field pattern of E and H plane. The width of the sample holder is large enough to cover the signal between the antennas temperature and bulk density respectively. The calibration model for measurement of grain moisture content is proposed to reduce the effects of fluectuations in bulk density and temperature which give serious errors for the measurements . From the results of regression analysis using the statistically analysis method, the moisture content of grain samples (MC(%)) is expressed in terms of the output voltage(v), temperature (t), and bulk density of samples(${\rho}b$)as follows ;$$MC(%)\;=\;(-3.9838{\times}10^{-8}{\times}v^{3}+8.023{\times}10^{-6}{\times}v^{2}-0.0011{\times}v-0.0004{\times}t+0.1706){\frac{1}{{\rho}b}}{\times}100$ Its determination coefficient, standard error of prediction(SEP) and bias were found to be 0.9855, 0.479%w.b. and -0.0.369 %w.b. respectively between measured and predicted moisture contents of the grain samples.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.28-34
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• 1982

This experiment was conducted to study on some morphological characteristics of rice grain and chaff with specific gravity. The size of grain was greater in grains with heavier specific gravity. Indica varieties were large in length, but short in width and thickness of grain, and was thin in grain form and small in volume of grain compared with Japonica variety. The coefficient of variability was high in grains with lower specific gravity. The accumulation of assimilation product was more influenced with width and thickness rather than length of grain. The percentage of fully ripened grain was high in small size variety. The green rice and imperfect grain showed higher distribution ratio in the lower specific gravity. The chaff of less filled grain had higher content of nitrogen and lower content of potassium and sillicate than the filled.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.286-288
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• 2019

Pseudomonas parafulva PpaJBCS1880 (PpaJBCS1880) isolated from rice seeds showed strong antagonistic activity against bacterial plant pathogens by producing lipopeptide. Furthermore, the strain controlled the incidence of bacterial pustule in soybean plants and promoted the growth of rice plants. Here we present complete genome sequence of PpaJBCS1880. The genome comprises of 5,208,480 bp with GC content of 63.4%, which includes 4,487 predicted protein-coding genes, 19 rRNAs, and 74 tRNAs. Genome analysis revealed genes encoding antimicrobial secondary metabolites such as lipopeptide, pyoverdine, phenazine, and hydrogen cyanide, which are known to play essential roles in biocontrol of plant diseases.

• Research in Plant Disease
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• v.26 no.4
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• pp.195-201
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• 2020

Rice bacterial leaf blight (BLB) by Xanthomonas oryzae pv. oryzae (Xoo) is considered to be one of the major rice diseases steadily occurring around the rice-producing countries. In this study, we developed a recombinase polymerase amplification (RPA) assay for the rapid, convenient and specific diagnosis of Xoo by targeting Xoo-specific transposase A gene. As the target gene can be amplified in 10 min without DNA extraction process and special equipment for temperature control, RPA for BLB can be useful and practical component for on-site diagnosis.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.97-101
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• 2001

The transport and allocation of photosynthetic assimilate is an important regulatory factor in plant productivity, In order to modify assimilate partitioning in rice, transgenic plants containing a potato sucrose transporter (SuT) gene were developed. Calli derived from rice seeds (Oryza sativa L. cv Dongjin) were cocultured with A. tumefaciens LBA 4404 harboring the SuT gene. Calli were transferred to MS medium supplemented with 50 mg/L hygromycin, 500 mg/L carbenicillin, 2 mg/L kinetin, 0.1 mg/L NAA. After 2 weeks, hygromycin resistant shoots were obtained from the calli on the selection medium. Roots were induced from the putative transgenic shoots on rooting MS medium supplemented with 250 mg/L cabenicillin. Plant regeneration rate from the calli was about 150%. Stable incorporation of the potato SuT gene into rice genomic DNA was confirmed by PCR and Southern blot analysis.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.135-143
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• 2018

The effect of elevated temperature on temperate paddy rice will be significant for dependable food supply in East Asia. Using temperature gradient field chamber (TGFC), which was designed to make the horizontal air temperature gradient by $0^{\circ}C$ to $3^{\circ}C$ higher than outside, we examined the measurement to understand the effects of extremely high temperature on paddy rice. In particular, the data of the year 2016, the worst heat wave in over 22 years, was analyzed in this study. The rice height in the relatively warmed condition was rapidly increased during early growth stage. However, the average grain weight and number of spikelet per panicle in the warmed chamber condition were gradually declined with increasing air temperature averaged for 40 days after first heading in each chamber. In particular, the grain yield was more dramatically decreased by the raising temperature because the percent ripened grain was quickly dropped as getting over the threshold temperature for pollination. Therefore, the surplus photosynthetic product by such lower grain filling rate may disturbed the decreases of the NDVI (Normalized Difference Vegetation Index) and SPAD chlorophyll values after first (normal) heading. In addition, the late-emerging head grain were appeared. However, this yield was too small to recover the normal yields decreased by extremely high temperature condition. Our result represented that the warmed condition in 2016 would be the critical limit for the stable yield of temperate paddy rice.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.18-26
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• 2013

Genetically modified (GM) rice Agb0101, which expresses the insecticidal toxin modified cry1Ac (mcry1Ac1) gene, was developed by the Rural Development Administration in Korea. To monitor the probable release of Agb0101 in the future, it is necessary to develop a reliable detection method. Here, we developed the PCR detection method for monitoring and tracing of GM rice. The primer pair (RBEgh-1/-2) from a starch branching enzyme (RBE4) gene was designed as an endogenous reference, giving rise to an expected PCR amplicon of 101 bp. For the qualitative PCR detection, construct- and event-specific primers were designed on the basis of integration sequence of T-DNA. Event-specific PCRs amplified specifically 5'- or 3'-junction region spanning the native genome DNA and the integrated gene construct, while none of amplified product was shown on crops, rice varieties, and other insect-resistant transgenic rice lines. The event-specific real-time PCR method was performed using TaqMan probe and plasmid pRBECrR containing both rice endogenous gene RBE4 sequence and 5'-junction sequence as the reference molecule. The absolute limit of quantification (LOQ) of real-time PCR was established with around 10 copies for one plasmid molecule pRBECrR. Thereafter, the different amounts of transgenic rice (1, 3, 5, and 10%, respectively) were quantified by using the established real-time PCR method, with a range below 19.55% of the accuracy expressed as bias, 0.06-0.40 of standard deviation (SD) and 3.80-7.01% of relative standard deviations (RSD), respectively. These results indicate that the qualitative and quantitative PCR methods could be used effectively to detect the event Agb0101 in monitoring and traceability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.115-120
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• 1989

Universal characteristics of ginseng replanting problems appeared to be decrease in root yields due to root rot and inhibition of root growth. Incitants of ginseng replanting problems have not been clearly elucidated, however, it appeared to be a complex phenomenon with several pathogenic soil microorganisms and environmental changes in the soil due to decomposition of ginseng debris such as rootlets and shoots. Decomposition of ginseng debris may cause direct or indirect damage to the root. The effect of conventional fungicide on the control of the problems has not been recognized. However, it has been suggested that treatment with soil fumigants may solve the problems. Meanwhile paddy-rice and ginseng rotation system appeared to be the best way of solving the problems so far.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.156-161
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• 2002

Two different cDNA clones for superoxide dismutase (SOD) were isolated from an weedy rice variety (Oryza sativa, cv. Bhutan14Ad) and were introduced into a cultivated rice variety (Oryza sativa, cv. Nakdong) in order to develop the environmental stress-resistant rice plants. Sequence analysis of the cloned cDNAS indicated that the deduced amino acid sequence of SOD-A is 88.4% identical to that of SOD-B. Furthermore, the nucleotide sequence of SOD-A is 99.3% identical to that of a Cu/Zn SOD gene of Oryza sativa (GenBank accession No. L36320). The nueleotide sequence of SOD-B was identical to that of the previously published SOD gene (Accession No. D01000). A cultivated rice variety, Nakdong-byeo, was transformed with chimeric SOD genes containing a actin promoter of rice and pin2 terminator using a particle bombardment technique. Transformed calli were selected on an selection medium containing phosphinothricin (PPT). Transgenic rice plants were regenerated from the PPT-resistant calli. PCR analysis with genomic DNAs from transgenic plants revealed that transgenes are introduced into rice genome.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.4
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• pp.233-240
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• 1982

This study was conducted to elucidate the translocation pattern of photosynthate labelled by $^{14}C$ in rice cultivars and the effects of nutrient composition on the translocation in rice plant during ripening, Showing coincidence between the grain filling rate and the translocation of $^{14}C$ into the grain during ripening period, the translocation patterns of cultivars tested were grouped by three; 1) the late dominance type (Akibare), 2) the early dominance type (Taebaegbyeo, Chupungbyeo), and 3) the semi-late dominance type (Milyang #23, Milyang #42, and Yushin). The negative relation ship existed between the translocation ratio of $^{14}C$ into the grain and the nitrogen content in plants, but not significant, The nutrient depletion of P, K, Ca, Mg, and Si in water medium from the panicle initiation to the heading stage resulted in the decrease of grain weight by 4 to 12 percent and the increase of translocation of $^{14}C$ into grain assimilated at heading. The effect of resupply of these nutrients after heading was recognized by the order of P>Mg>K and Ca. But the effect of Si resupply was hardly recognized in increasing grain weight. The photosynthetic rate was greatly affected by the nitrogen status and the depletion of P, K, and Ca decreased the photosynthetic rate in single leaf at heading, while the depletion of Si enhanced the rate.