• 한국약용작물학회지
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• 제12권3호
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• pp.226-230
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• 2004

재배 생력용으로 많이 이용되고 있는 멀칭 방법이 삽주의 생육에 미치는 효과를 구명하여 최적 멀칭방법을 확립하고자 무멀칭, 볏짚, 투명비닐, 흑색비닐, 이들 비닐과 왕겨를 혼용한 멀칭이 삽주의 어린싹, 초기 및 후기 생장과 수량에 미치는 영향을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. 삽주의 어린싹 무게는 투명 비닐을 이용한 멀칭에서 가장 많았던 반면, 어린싹과 관련된 형질중에서는 엽수, 어린싹의 길이는 볏짚을 이용한 멀칭에서 가장 작았다. 2. 생장초기에는 볏짚을 이용한 멀칭시 엽수, 근수, 경수, 엽폭, 지상부 및 근경의 생체중이 가장 적었던 반면, 왕겨와 흑색비닐 혼합멀칭시 뿌리 관련 형질인 근수, 근경중 및 근중이 가장 많았다. 3. 생장후기에는 지온이 낮았던 생장초기의 멀칭효과가 고온기를 경과하면서 그 효과가 사라져 생장 및 형태적 형질에서는 멀칭처리간 차이가 거의 없었다. 4. 단위면적당 수량과 상품 수량은 볏짚 단독멀칭과 왕겨와 흑색비닐의 혼합멀칭 에서 가장 높았다.

• The Plant Pathology Journal
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• 제26권1호
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• pp.70-79
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• 2010

Rice blast is one of the serious devastating diseases. This study was carried out to determine the genetic diversities of blast resistance (R) genes form 86 accessions of aromatic rice with eight SNP markers, z4792, zt4792, z60510, zt6057, k6415, k6411, k39575 and t256, which showed the close-set linkage to 6 major genes, Piz, Piz-t, Pik, Pik-m, Pik-p, and Pit. Four accessions of indica type, Mayataung, Yekywin Yinkya Hmwe, Basmati9-93, and Basmati5854, showed the positive amplicons of six major genes. Among 86 accessions, 83 accessions were detected both or one of Piz and Piz-t genes. Seventy three accessions contained the Piz gene with z4792 marker. In addition, 30 and 71 accessions possessed Piz-t gene with zt4792 and zt6057 markers, respectively. Ten accessions showed the positive bands for the Piz-t gene with both zt4792 and zt6057 markers. Only one accession, Khau Nua Keo, was not amplified for both Piz and Piz-t gene. But japonica type, Gerdeh, possessed only Piz gene between Piz and Piz-t. Fifty two accessions showed the three of Pik multiple genes and Pit gene. Four accessions, Iari7447, Daebunhyangdo2, Shiyayuuine, and Basmati 6129 possessed a Pik-p gene. Especially, Pit gene on chromosome 1 was detected with t256 marker in all of 83 accessions, exception of A-2, one accession of japonica type.

• 한국작물학회지
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• 제25권4호
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• pp.1-9
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• 1980

To determine the optimum harvest time of recent rice varieties from Indica/Japonica remote crosses, leading varieties Suweon 264 and Milyang 23 were tested for the changes in dry matter weight and moisture content of grain, shattering, shelling ratio, milling ratio, and apparant physical quality during grain development at 5 day-intervals from 20 days to 55 days after heading. The results are summarized as follows: 1. Grain weight (dry matter) reached its maximum (physiological maturity) at 30 days after flowering (DAF) in Suweon 264, and at 35 days in Milyang 23, and thereafter it did not change significantly until 55 DAF. 2. Time course of decrease in grain moisture content (Y, %) during maturation (X, DAF) consisted of two linear phases, i.e. a fast and a slow period: Y=68.245-1.33X until 34DAF, and Y=23.025-0.470X until 55DAF after 34DAF in Suweon 264; Y=73.62-1.634X until 24.5DAF, and Y=33.59-0.570X until 55DAF after 24.5DAF in Milyang 23. Two varieties showed the same grain moisture content of 28% (wet basis) at physiological maturity in spite of the distinct differences in the heading date, time of physiological maturity and thereby ripening climate. 3. Force to shatter a grain ranged about 90 to 100g in Milyang 23, and about 200 to 250g in Suweon 264 and in a Japonica variety, Jinheung. The force, however, did not change significantly with harvest time from 35DAF to 50DAF. 4. The changes in the ratios of shelling, milling, broken rice and tinted rice with harvest time were insignificant during a period from 35DAF to 55DAF. However, ratios of green rice and white belly rice decreased significantly with delay in harvest time during 10 days after physiological maturity. 5. The best time of harvest for maximum yield and good quality is thought to be 10 days after physiological maturity, and grain moisture content at this time was about 20% on wet basis.

• 한국버섯학회지
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• 제15권1호
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• pp.57-60
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• 2017

큰느타리에 대한 국내산 자포니카타입의 벼에서 부산물로 나오는 미강을 대체할 수 있는 재료를 선발하기 위해 파키스탄에서 생산된 인디카 타입의 벼에서 생산된 미강과 옥수수주정박, 호마박, 케이폭박을 이용하여 시험한 결과 다음과 같다. 혼합배지별 이화학성 중 총탄소함량은 T1에서 가장 높았고, 총질소함량은 T4에서 가장 높았다. C/N은 T2가 대조구와 대등하였고, 갓직경과 대길이는 T1과 T2에서 컸다. 수량 및 생물학적 효율은 T2에서 다른 처리구 보다 높았으며, 대조구와 대등한 값을 나타내었다. 따라서 미강팰릿을 큰느타리 병재배에 첨가하여 사용할 수 있을 것으로 판단되었다.

• 한국작물학회지
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• 제47권2호
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• pp.127-131
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• 2002

Critical nitrogen concentration (Nc), which is defined as the minimum % N in shoots required to maintain the maximum growth rate of top dry weight (W) at any time, was determined for rice plant. Using two rice varietal groups, japonica varieties and an indica $\times$ japonica "Dasanbyeo", 18 data points fulfilling the statistical criteria for determining Nc were obtained through eight N-fertilization experiments over two years at Suwon (37$^{\circ}$16'N), Korea. Nc dilution curve for each variety was obtained by fitting the Nc-W relationship to power function. However, The critical nitrogen curves for the two variety groups were not different statistically. Thus, a Nc dilution curve was fitted for the Nc data points pooled over the two variety groups and proposed in rice as: Nc=4.08, where W＜1.73 t h $a^{-1}$ , Nc=5.197 $W^{0.425}$3/ ($R^2$=0.964), where 1.73 t h $a^{-1}$ ＜W＜12 t h $a^{-l}$. The Nc for W＜1.73 t h $a^{-l}$ were estimated as a constant value of 4.08%, the mean value of the maximum N concentration for N-limiting condition and the minimum N concentration for N non-limiting condition. The model for Nc is applicable to diagnosing the nitrogen nutrition status during the rice growth period from emergence to heading stage. The Nc curve well discriminated the 144 data points between the N limiting and the N non-limiting groups regardless of varieties, cultural methods, and years.-limiting groups regardless of varieties, cultural methods, and years.

• Journal of Crop Science and Biotechnology
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• 제11권3호
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• pp.205-214
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• 2008

Blast disease caused by the fungal pathogen, Magnaporthe oryzae, is one of the most damaging diseases in rice. The use of resistant varieties is an effective measure to control the disease, however, many resistant varieties were broken down to their resistance effects by the differentiating of new virulent isolates. This study was done to analyze the haplotypes of 31 microsatellite markers linked to five major R genes and two QTLs and to identify the alleles for the putatively novel genes related to durable resistance to blast in 56 Korean japonica and four indica varieties. The 31 microsatellite markers produced 2 to 13 alleles(mean = 5.4) and had PICi values ranging from 0.065 to 0.860(mean=0.563) among the 60 rice accessions. Cluster analysis based on allele diversities of 31 microsatellite markers grouped into 60 haplotypes and ten major clusters in 0.810 genetic similarity. A subcluster IV-1 grouped of early flowering varieties harboring Piz and/or Pi9(t) on chromosome 6 and Pita/Pita-2 gene on chromosome 12. The other subcluster V-1 consisted of four stable resistance varieties Donghae, Seomjin, Palgong and Milyang20. The analysis of putative QTLs associated with seven blast resistance genes using ANOVA and linear regression showed high significance to blast resistance across regions and isolates in the markers of two genes Piz and/or Pi9(t) and Pita/Pita-2. These results illustrate the utility of microsatellite markers to identify rice varieties is likely carrying the same R genes and QTLs and rice lines with potentially novel resistant gene.

• Journal of Biosystems Engineering
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• 제17권3호
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• pp.272-284
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• 1992

As a preliminary step toward the development of a multipurpose electrostatic separator for agricultural use, this study investigated the effect of moisture level, geometrical characteristics and the electric field strength of a charging device on the electrostatic charging of brown rice, unhulled paddy, small stones and broken rice that are produced during the milling process. The results are summarized as follows. 1. Average electrostatic charge per unit mass of paddy is greater than that of brown rice. 2. Charge per unit mass of rice kernel increases linearly with moisture content and electric field strength of the charging device, presenting no correlations with length or thickness of rice kernel. 3. Frequency distributions in electrostatic charge per unit mass of paddy and brown rice kernels indicated that the portion, not overlapped, ranged from 10 to 29% with Japonica rice and from 32 to 49% with Indica rice. 4. The difference in moisture content between paddy and brown rice must be over 6%, if they are to be electrostatically separated to over 95%. 5. Theoretical portions of brown rice to be separated from a mixture primarily by the electrostatic charge and secondarily by the length or by the thickness were 95~100% and 27~76%, respectively. 6. Frequency distribution of electrostatic charge for broken kernels overlapped that of paddy and brown rice, which the small stones didn't.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.926-936
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• 1996

Field hulling of high-moisture paddy followed by brown rice drying offers many advantages over the present paddy harvesting and drying offers many advantages over the present paddy harvesting and drying system. We did a preliminary study of the parameters for efficient hulling of high-moisture paddy using the IRRI Centrifugal Huller and two India rice varieties. Hulling capacity , hulling efficiency , brown rice recovery and percent whole bown rice were generally best at the impeller peripheral speed of 44m/s. A second pass through the huller increased hulling capacity , brown rice revery and hulling efficiency, but reduced percent whole brown rice. To solve this , we recommed separation of paddy after hulling and aspiration such that only unhulled and partially -hulled grains will be fed back to the huller. Paddy at even 23% m.c. could be effectively hulled by the impeller-type huller , but the results were generally better at 14 to 17% m.c. Only in percent whole brown rice did the 17 to 23% m.c. range performed better than that of 14% m.c. Difference invarietal response to hulling was observed.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.116-117
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• 2000

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 춘계학술대회
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• pp.126-126
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• 2022