• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.27-32
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• 2011

This study was carried out to investigate characteristics of new garlic cultivar 'Alkae' and to identify the effect of scape removal on bulb characteristics and growth of garlic cultivar 'Alkae' and 'Namdo'. Bolting time and harvesting time were earlier about 20 days in 'Alkae' than those in 'Namdo'. 'Alkae' was inferior to 'Namdo' in top growth as plant height, number of leaves, leaf area, SPAD value, diameter of leaf sheath, and so on. but root developing was better in 'Alkae'. Bulb weight of' Alkae' was 17% more than that of 'Namdo', harvested on proper time. The ratio of bulb weight over 40 g was almost double in 'Namdo' as 48% with 'Alkae' as 25%. Occurrence of bulb cracking was more considerable in 'Alkae' and the number of clove per bulb was 1.9 more in 'Alkae' than 'Namdo', but the ratio of bulb rot during storage was higher in 'Namdo' than 'Alkae'. In treatments of scape removal, SPAD value did not show any difference between two cultivars. Leaf dryness was earlier and harder than control and leaf area showed the same tendency as leaf dryness, and there were no significant differences among the methods of scape removal. The bulb weight and the ratio of bulb weight over 40 g at 50 days after the harvest of 'Alkae', 'Namdo' were more 10%, 12% and 27%, 44% in scape removal treatment than control. and there were no significant differences among the methods of scape removal. So, scape removal was very effective to increase large bulb production in the two garlic cultivals and the effect was higher in 'Namdo' than 'Alkae'. The ratio of bulb cracking and the occurrence of bulb rot were almost same in with the scape removal and non removal groups And also there were no significant differences among the methods of scape removal.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.309-313
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• 2006

Discovery of single nucleotide polymorphisms (SNPs), including small insertions and deletions, is one of the hot topics in genetic research. The most common type of sequence variant consists of single base differences or small insertions and deletions at specific nucleotide positions. Significance of SNPs in rice is increasing for genetic research, positional cloning and molecular breeding. $F_2$ 170 lines and $F_3$ 194 lines derived from Sangjuchalbyeo/HR13721-53-3-1-3-3-2-2 Were used for Searching SNP markers related to bacterial blight resistance. Sangjuchalbyeo is susceptible to bacterial blight, but HR13721-53-3-1-3-3-2-2 has Xa1 gene resistant to bacterial blight. Individual lines were inoculated with $K_1$ race of bacterial blight and resistant or susceptible was evaluated after 3 weeks from inoculation. The genotypes of population were analysed by PCR-RFLP for SNP marker developing. The segregation of $F_2\;and\;F_3$ population showed almost 3:1, 1:1 ratio, respectively. Analysis of genotype using SNP marker is capable of confirming resistance for $K_1$ race and genotype through amplifying the gene using 16PFXal primer and digested the PCR product with Eco RV. There were close relation between resistance test for $K_1$ race and SNP marker genotype. Especially, DNA analysis using SNP marker is capable of judging homozygote/heterozygote in $F_2$ population compared with resistant test for Kl race. So, it seems to improve the selection efficiency in disease resistant breeding.

• Research in Plant Disease
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• v.14 no.3
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• pp.171-175
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• 2008

The influence of rice bacterial leaf blight (BLB) disease incidence on yield and quality of Nampyung, Gang-baek and Iksan493 was investigated in three areas, Gimje, Yeongam and Jangheung, frequently found BLB infested rice. The infection rate of Nampyung, susceptible to BLB disease, was higher ($23{\sim}93%$) than Gang-baek ($2{\sim}15%$) and Iksan493 ($2{\sim}6%$), have resistant gene Xa7 and xa5, respectively. BLB disease incidence was severely found in Gimj and then yield of Nampyung was reduced 65% (352 kg/10a) compared to Iksan493 (540 kg/10a) due to the decrease in the ripen grain filling, brown/rough ratio and 1,000 grain weight. There was no difference of rice yield among Nampyung, Gangbaek and Iksan493 in Yeongam and Jangheung. The occurrence time of disease in Yeongam and Jangheung was later than Gimje and BLB disease was less infected in these areas. BLB infected rice grain showed inferior grain appearance and taste index to sound grain. independent of rice with resistant gene. In Yeongam and Jangheung, Gangbaek and Iksan493 cultivated showed lower ratio of white color to belly than Nampyung. Iksan493 showed better grain appearance and lower ratio of white core to belly than Gangbaek. In protein content of rice grain, the range of Gangbaek and Iksan493 was $6.9{\sim}9.8%$, but Nampyung showed unstable ranged from undetermined to 9.0%.

• Journal of Life Science
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• v.14 no.4
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• pp.650-656
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• 2004

Oryza grandiglumis (CCDD, 2n=48), one of the wild rice species, has been known to possess fungal-,bacterial-, and insect-resistance against sheath blight, rice blast, bacterial leaf blight and brown plant hopper (Nilaparvata lugens). To rapidly isolate differentially expressed genes responding to fungal and wounding stress, wounding and yeast extract were treated to O. grandiglumis for 24 hrs. Suppression subtractive hybridization (SSH) method was used to obtain differentially expressed genes from yeast extract and wounding treated plants. Seven hundreds and seventy six clones were obtained by subcloning PCR product, and colony array and screening were carried out using radio-isotope labeled cDNA probes prepared from the wounding and yeast extract treated plants. One hundred and fifteen colonies were confirmed as true positive ones. Average insert size of the clones were ranged from 400 bp to 700 bp and all the inserts were sequenced. To decide the identity of those clones, sequences were analyzed by sequence homology via GenBank database. The homology search result showed that 68 clones were matched to the genes with known function; 16 were related to primary metabolism, 5 to plant retrotransposons, 5 to defense related metallothionein-like genes. In addition to that, others were matched to various genes with known function in amino acid synthesis and processing, membrane transport, and signal transduction, so on. In northern blot analysis, induced expressions of ogwfi-161, ogwfi-646, ogwfi-663, and ogwfi-695 by wounding and yeast extract treatments were confirmed. The result indicates that SSH method is very efficient for rapid screening of differentially expressed genes.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.139-148
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• 2003

The purpose of this study was to investigate damages of garlics occurred under cold storage and farmhouse storage condition, influence of cultural and environmental factors on storage spoilage of garlics, and to establish control strategies to reduce damages occurred under storage of garlics. Decays of garlics were highly related with cultural condition (paddy field or upland soil), ventilation, storage temperature and relative humidity, continuous cropping years, and harvesting stage. Early-harvested garlics were more decayed than late-harvested garlics. Garlics cultivated on paddy field were less decayed than ones cultivated on upland soil under farmhouse storage condition. The densities of Penicillium spp. and Fusarium spp. were higher on plot with long term continuous cropping cultivation history than on plot with short term continuous cropping cultivation history. However there is no relation between continuous cropping years and percent of decay of garlics. As a result of investigating influence of environmental factors on decay of garlics, P. hirsutum caused severe spoilage under high relative humidity condition, while F. oxysporum and Stemphyllium botryosum were not related with relative humidity. The three postharvest pathogens grew well above woe. In addition when P. hirsutum and S. botryosum were cultured for two months, they grew even at $-1^{\circ}C$. Except for environmental factors, wounds occurred through farming works. had an effect on storage spoilage of garlics. Garlics only hurt with a toothpick without inoculation of pathogens were decayed more severe than those inoculated with pathogens without wounds. Seven agro-chemicals showed highly suppressive effect were selected by measuring mycelial growth of three major pathogens of garlics on potato dextrose agar amended with 0.1% (v/v) of each fungicide. When they were foliar-sprayed on garlics 30 days before harvesting, it was confirmed that they suppressed storage spoilage of garlics. Also when garlics were sprayed with and drenched into the suspension of Benoram WP very after harvesting garlics, garlic damages by postharvest pathogens were reduced remarkably.

• The Journal of Natural Sciences
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• v.7
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• pp.91-101
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• 1995

To establish the simple and practical test method of estimating resistance of rice varieties against rice leafblight, trials were made to correlate among the four test methods such as true resistance test,secondaryinfection test, secondary epidemic test and field test. The results obtained through the experiment on 25 ricevarieties and 3 pathogenic isolates designated to HB9O11, HB9022 and HB9033 can be summarized asfollows. 1 .Based on the results of true resistance test, 25 rice varieties can be classified into four groups:1 )Samgang variety group ;resistant to HB9011, 13 varieties, 2)Pungsan variety group ; resistant to HB9011 and HB9022, 5 varieties, 3)Samgang variety group ; resistant to all three isolates, 2 varieties, 4)Unbongvariety group: sensitive to all three isolates, 12 varieties. 2. The responses of rice varieties to isolates showed some discrepancies among on the test methods. These examples were found in 3 varieties including Yeongdeog varieties to HB9011, 3 varieties including Taebaeg variety to HB9022 and Taebaek vaieties to HB9033. 3. Correlation coefficiences between the secondary infection test and the secondary epidemic test for HB9011, HB9022 and HB9033 were 0.972, 0.894 and 0.919, respectively. It suggests that the two methods are not significantly different so that one of the two methods are not significantly different so that one of the two methods can be omitted from resistant test without affecting the result. 4. Between the true resistance test and the field test at the disease common area, there were no significant correlations. Unbong, Chucheong and Yeongdeog varieties are appeared as resistant varieties in the true resistant test, but their responses in the field test were different and appeared as sensitive varieties. 5. The disease index was used to express theresults from four test methods. The disease index was calculated as the sum of each numerical values of theresults from the four test methods by giving the same weights(0 to 25)to each test method. If the disease index for certain variety is less than 15, then the variety is considered to be resistant. 4 varieties such as Seohae, Hwajin, Yeongdeog and Pungsan varieties-disease indices were less than 15 were selected as field resistance varieties.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.147-153
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• 1975

During 1973 a field experiment was carried out to evaluate effectiveness of the root zone application of insecticides in medical gelatin capsules for control of several rice insect pests and dwarf virus disease. At three days after transplanting the capsules were pushed by hand about 2.5cm into the soil, near roots of Tongil rice plants. At the given day intervals number of leaf-and plant-hoppers on the hills were recorded by direct count, and dead hearts and white heads by stem borers and dwarf virus infected hills were observed in the experiment plots. Finally grain yields were measured. The percentages of dead hearts and white heads in all the plots were too low for evaluating the effectiveness of insecticides against the striped rice borers. Carbofuran of the insecticides tested was relatively effective against green rice leafhopper (Nephotettixcincticeps) and small brown planthopper (Laodelphax striatellus), although small number of insects on the hills were recorded. Relatively small number of white-backed planthopper (Sogatella furcifera) was occured in the BPMC and Diazinon treated plots. BPMC and Carbofuran were highly effective against the brown planthopper (Nilaparvata lugens) to 80 days after treatment. Incidence of dwarf virus disease was least in the plots of Carbofuran treatment. The highest grain yield was recorded in the plots treated with Carbofuran, and it seemed to be related with good protection from the dwarf virus disease and leaf-and plant-hoppers.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.67-76
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• 2016

This study was conducted to examine the optimal environmental condition for promoting the growth of sowthistle as affected by light quality and photoperiod in a closed-type plant production system. Seeds were sown in 240-cell plug trays and then germinated for 3 days at a 24-hour photoperiod in a closed-type plant production system with LED lights (R:B:W = 8:1:1). Seedlings were transplanted and grown under 3 types of LED (R:B:W = 8:1:1, R:W = 3:7, or R:B = 8:2) and 4 photoperiods (24/0, 16/8, 8/16, or 4/20 hours) with $230{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity at a density of $20cm{\times}20 cm$. The experimental design was a randomized complete block design. Plants were cultured for 40 days un der the condition of $21{\pm}2^{\circ}C$ and $70{\pm}10%$ relative humidity after transplanting. Plants were fed with a recycling nutrient solution (pH 7.0 and EC $2.0dS{\cdot}m^{-1}$) contained in a deep floating tank. Fresh weight and dry weight of shoot or root, leaf length, and leaf area were the greatest in the photoperiod of 24/0 (light/dark) with RW LED. The highest number of leaves occurred in the photoperiod of 16/8 (light/dark) with RB LED, while the incidence of tip burn was higher in the photoperiod of 24/0 (light/dark) compared to the other treatments. Chlorophyll value was the highest in the 16/8 (light/dark) photoperiod and there was no significant difference by light quality. Chlorophyll fluorescence was the lowest in the photoperiod of 24/0 (light/dark) compared with other treatments. Therefore, in terms of economic feasibility and productivity for Ixeris dentata Nakai cultivation in a closed-type plant production system, the results obtained suggest that plants grew the best when kept in a photoperiod of 16/8 (light/dark) and light quality of combined LED RW (3:7).

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.547-551
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• 2009

A new commercial rice variety "Chilbo" is a japonica rice (Oryza sativa L.) with resistance to rice stripe virus and high grain quality. It was developed by the rice breeding team of Yeongdeog Substation, NICS, RDA in 2007. This variety was derived from a cross between "Yeongdeog 26" with wind tolerance and lodging resistance and "Koshihikari" with good grain quality. A promising line, YR21324-119-3-2 was selected by a pedigree breeding method and designated as "Yeongdeog 44" in 2004. Regional adaptation yield trials were carried out at eleven locations from 2005 to 2007. As a result, "Yeongdeog 44" was released as a high yielding rice variety with high grain qualilty and virus resistance with the name of "Chilbo". It is short 76cm in culm length and has medium-late growth duration. This variety is resistant to stripe virus and middle resistant to leaf blast disease. It is also tolerant to cold, dried wind. Milled rice kernel of "Chilbo" is translucent, clear in chalkiness. Panel test proved that and it has good eating quality. Head rice ratio of Chilbo is high compared to the check variety, Hwaseongbyeo. Yield potential of "Chilbo" in milled rice is about 5.57MT/ha at ordinary fertilizer level of local adaptability test. This variety would be adaptable to Yeongnam plain, south & east-south coastal, south mid-mountainous, middle plain area of Korean peninsula.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.328-331
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• 2008

Hwangeumnodeul is a new japonica rice cultivar developed from a cross between Milyang165 and HR15151-B-21-3 at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2007. This cultivar has short grains and about 139 days of growth duration from direct seeding to harvesting in the southern plain areas. Culm length of this cultivar is 78 cm and the number of spikelet per panicle is similar to that of the check cultivar, Nampyeongbyeo, while filled grain rate is lower than the check variety. This cultivar is moderately resistant to leaf blast, bacterial blight pathogens of $K_1$, $K_2$ and $K_3$ and stripe virus but susceptible to major virus diseases and insect pests. Milled kernel of Hwanggeumnodeul is translucent with non-glutinous endosperm. This cultivar has about 5.7% and 18.6% of protein and amylose contents, respectively. Palatability of cooked rice of Hwanggeumnodeul is similar to Nampyeongbyeo. Its milling recovery and head rice were 75.6% and 90.0%, respectively. Hwanggeumnodeul yielded 5.69 and 5.61 MT/ha in milled rice at the under wet-direct and dry-direct seeding conditions, respectively which are 17% and 12% higher than the check variety, Juanbyeo. It yielded 5.86 MT/ha, 8% higher than Nampyeongbyeo at the standard fertilizer level of the ordinary transplanting cultivation. "Hwanggeumnodeul" would be adaptable for ordinary transplanting as well as direct seeding in the southern plain including Chungcheong province.