• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.2
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• pp.86-95
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• 1983

Evapotranspiration is a major factor determining the water consumption in the rice fields. Therefore, realistic evapotranspiration estimates are important to the agricultural water resources planning. In Korea, however, the Blaney-Criddle formula, which was developed under the meteorological condition of western arid United States and the upland cultivation, has been widely used to estimate evapotranspiration from paddy fields. Hence, it has considered that the Blaney-Criddle formula would not be the proper method for the Korean paddy condition. The purpose of this study is to select the most appropriate and realistic method for estimating evapotranspiraion from paddy field in Korea and to derive crop coefficients using the chosen method. The results are summerized as follows. 1. Total seasonal-average evapotranspiration by the field observation was 660mm for Tongil and 621. Ornm for the Japonica variety of rice. The amount of evapotranspiration for Tongil variety was 6% larger than that of the Japonica variety. 2. There was no significant differences in the amount of evapotranspiration among early, middle and late mature varieties, that is, early 638mm, middle 627mm and late 630mm for the whole growing season. 3. The rate of peak evapotranspiration appeared at the beginning of August and was in the range of 7.7-8. Omm/day according to the different mature varieties. 4. The correlation between pan evaporation data and the calculated evapotranspiration using related meteorological data from various methods suggested such as Radiation (FAO), Hargreaves, Christiansen, Hargreaves-Christiansen, Jensen-Haise, showed high statistic significance. Therefore, it seemed to use those formulars in estimating evapotranspiration inste4 of using pan evaporation data. 5. It was concluded from the analysis of field data that the evapotranspiration estimate for Blaney-Criddle method might not be appropriate in Korea. On the other hand, Penman equation showed more accurate estimation at the flourishing stage of rice than the pan evaporation method. 6. The crop coefficients for the Penman and pan-evaporation method were obtained by graphical representation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.2
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• pp.121-125
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• 2004

In plants, nitrogen is the major component for growth and development. Leaf growth is based on the division, elongation and maturation of cells, which are used for making of epidermis, mesophyll, bundle sheath, xylem, phloem and so on. Dynamics of these tissues with respect to nitrogen are required for better understanding. This experiment was conducted to evaluate effect of nitrogen on the elongation of epidermal and guard cell of two rice (Oryza sativa L.) varieties, Seoanbyeo and Dasanbyeo on May 2000 at Chungbuk national university in Cheongju. After transplaning the 20-day-old seedlings into a/5000 pots, the main characteristics related with cell elongation were investigated and evaluated. A maximum. leaf length reached at 7 or 8 days after emerging from the collar, and also the leaf elongation rates were greatly affected by the increase of N application rate. The initial and final cell length were about $17\mu\textrm{m}$ and $130\mu\textrm{m}$, respectively. Cell divisions occurred within 1.0mm from leaf base. With die higher nitrogen application rate of 22 kg-N $10\textrm{a}^{-1}$, cell division per hour was greater 1.5 to 1.9 and 1.2 to 1.3 fold as compared to the N application rate of 0 and 11 kg-N $10\textrm{a}^{-1}$, respectively. Cell enlargement of epidermal and guard cell under higher N application rate (22kg-N $10\textrm{a}^{-1}$) was finished within about 20 (Seoanbyeo) and 15 hours (Dasanbyeo), while it took much time, about 30 hours.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.288-294
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• 1994

Dietary fiber contents in brans of the two representative Korean rice varieties, Chucheong and Sucheon were measured by the AOAC method, and the composition of total dietary fiber (TDF) was analyzed with the acid detergent fiber (ADF) procedure. Rice bran contained more than 25% of TDF, most of which was insoluble dietary fiber. Hemicellulose was shown to be the major constituent and rice bran dietary fiber contained distinctive amounts of cellulose and uronic acid. Consecutive acidalkaline treatment of rice bran considerably increased soluble dietary fiber (SDF) content and water-holding capacity (WHC). WHC of wheat flour-rice bran dietary fiber mixture increased with the proportion of rice bran dietary fiber. Analysis of the differential scanning calorimetry thermograms revealed that rice bran dietary fiber effectively retarded retrogradation of wheat starch.

• Journal of Plant Biotechnology
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• v.32 no.2
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• pp.85-90
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• 2005

This study was conducted to investigated the major characteristics of genetically modified rice of 'Milyang 204' originated from Dongjinbyeo compared to a non-transgenic rice varieties Dongjinbyeo and Jun-ambyeo. Basta resistant transgenic rice lines carrying bar gene produced by the Yeongnam Agricultural Research Institute were evaluated for their agronomic characters. The transgenic Japonica rice of 'Milyang 204' showed inferior phenotypic traits compared to a non-transgenic rice variety Dongjinbyeo and Junambyeo. On the basis of UPOV (Union Internationale Pour la Protaection des Obtentions Vegetables) and NSMO(National Seed Management Office) the transgenic 'Milyang 204' showed difference in some traits out of some agronomic traits, such as leaf color, angle of flag leaf, number of spikelets, culm length, white core and white belly compared to the non-transgenic varieties rice.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.585-593
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• 1988

The lipid contents and neutral lipid components of brown rice, milled rice and bran were studied for four varieties of rice such as Nampung, Milyang #23, Whasung and Jinhung. Total lipid contents of brown rice, milled rice and bran were 2.65%, 1.09% and 20.24% respectively. The ratios of neutral lipids, glycolipids and phospholipids in total lipids were 82.53:12.39:4.08 in brown rice and 87.72:7.02:5.26 in bran. Neutral lipids were separated on the TLC; among them 6 neutral lipids were identified by comparing the RF value of standards. Triglycerides(TG), free fatty acids(FFA) and steryl esters(SE) were major neutral lipid components in brown rice, milled rice and bran. TG content of the bran, compared to that of brown rice and milled rice, was very low in contrast the FFA content was high. The major fatty acids of total lipid and neutral lipid fractions were palmitic, linoleic and oleic acids, comprising over 95% of these classes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.378-383
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• 1989

For selection of mutants two rice varieties, Sangpungbyeo and Seomjinbyeo, were irradiated with 20 kR and 25 kR of gamma rays. One panicle per each plant was harvested in Ml, and single needling per hill was planted for M2 and M3 generations. Mutations for short culm, earliness and the major traits were examined. 1. The mutation rates were varied with the rice varieties and the doses of radiation, higher in Sangpungbyeo and 25kR than in Seomjinbyeo and 20 kR, respectively. 2. The rates in Sangpungbyeo with the 20 kR and 25 kR were 1.10％ and 1.47％. respectively and those of Seomjinbyeo were 0.51％ and 1.25％, respectively. 3. The culm lengths of short-culm mutants derived from Sangpungbyeo and Seomjinbyeo were reduced about 10％ compared to their mother varieties, especially it was possible to select the dwarf mutants reducing 57％ and 40％ of culm length in Sangpungbyeo and Seomjinbyeo, respectively with the dose of 25 kR irradiation. 4. The range of heading date of the mutant ion in the M3 generation was comparatively wide. Many earliness mutants shortened about 7 days were selected as compared with their mother varieties, some mutants of the irradiated group had early matured by 20 days and 30 days, respectively in both Seomjinbyeo and Sangpungbyeo.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.108-108
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• 2017

The objective of this study was to know prospect and present state of new variety breeding of Forage and Grassland in South Korea. The industry of forage in Korea is going up to expend through utilization of good quality forage, Italian ryegrass, forage corn and oat rather than rice straw. Especially, since 2007, Italian ryegrass(IRG) had been very important major winter forage crop in South Korea and developed 13 varieties including very early maturity variety (three varieties), early maturity variety (three varieties), medium maturity variety (one variety) and late maturity variety (six varieties). But the disadvantage of Italian ryegrass was weak winter hardness and drought but has good advantage of forage nutritive value, high-yielding and high sugar content, and like livestock as like hanwoo, dairy cattle, goat so on. The Ko-variety (Korea developed variety) of Italian ryegrass has high cold-tolerant and adaptability more than any other country developed variety, and expend to cultivation area from southern area (below Daejeon) to middle-northern area (upper Han river). Although the cultivation area of Italian ryegrass of South Korea was 21,700 ha in 2007, right now, that of Italian ryegrass is about 123,600ha due to expend cultivation area and know famer to good forage crop and have a various maturity varieties (very early, early, medium, late) according to local situation (before-crop harvesting stage or double cropping system). The seed market of Italian ryegrass in South Korea becoming extended to around 100 million Korean won and seed export get nearer to foreign country. We are going to develop of new variety for stress tolerant and high yield and quality forage variety, good adaptability to the Korean environmental conditions including reclaimed area, make self-sufficiency system for forage seed (Italian ryegrass), export our seed to foreign countries.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.153-162
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• 2016

We investigated the physicochemical properties and starch structure of various rice varieties including 15 colored cultivars. NKHC showed the highest level of protein, lipid, and total dietary fiber levels. Reddish brown rice showed higher lipid content than that in black rice cultivars. Apparent amylose content of waxy and non-waxy colored rice varieties was within the range of 3~5% and 15~18%, respectively. IP exhibited the highest total starch (TS) content, whereas, NKHC and HJJ showed lower TS content than that in other cultivars. Pasting temperature of all colored rice cultivars, except IP, was about $68^{\circ}C$. Peak viscosity of IP, JJJ, Hong, and GGHM showed high values of 138, 130, 128, and 124, respectively. All the colored rice cultivars presented A-type X-ray diffraction pattern and polygonal shapes of starch granules were observed using scanning electron micrographs (SEM). Major groups of amylopectin chain lengths were B (12 < DP ${\leq}$ 24) and A (DP ${\leq}$ 12). SMHC showed the highest B chain content and the lowest A chain content (P < 0.05). These experimental results provided useful information for scientists and the food industry regarding colored rice starches.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.133-133
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• 2017

Lodging is one of the important constraints in rice production. The lodging destroys the canopy structure, and sharply reduces the capacity of photosynthetic rate and dry matter production. In cereal crops, stem lodging can be classified into two types: stem breaking type and stem bending type. To improve stem lodging resistance, it is important to reveal strong culm traits of superior lodging resistant varieties. There are large varietal differences in parameters associated with the bending moment at breaking (M) and flexural rigidity (FR). The indica variety Takanari possesses large M due to its large section modulus (SM) despite of its small bending stress (BS), while Takanari also has large FR due to its large secondary moment of inertia (SMI) and Young's modulus (YM). To identify quantitative trait loci (QTLs) and the corresponding genes associated with the parameters for M ($=SM{\times}BS$) and FR ($=SM{\times}YM$) should enable to develop lodging resistant varieties, efficiently. In order to identify QTLs for cell wall materials such as cellulose, hemicellulose and lignin associated with BS and YM, a set of Chromosome Segment of Substitution Lines (CSSLs) consisted of 37 lines with chromosome segments of Koshihikari in the genetic background of Takanari were used. Takanari had large M and small BS as compared with Koshihikari. The QTLs for BS were estimated on chromosomes 3, 5, 6, 8, 9, 10, 11 and 12. Koshihikari alleles increased BS in these QTLs. Takanari had a large FR due to its large SMI and YM as compared with Koshihikari. The YM was increased by substitution of the Koshihikari chromosomal segments on chromosomes 2, 10 and 11. Other QTLs estimated on chromosomes 7 and 12 that Koshihikari alleles contributed to the decrease of YM. For lignin, only one major QTL for lignin density was detected on chromosome 11. Hollocellulose densities were increased by the substitution of Koshihikari segments on chromosomes 5 and 11. On the other hand, these were decreased on chromosomes 1 and 3 by substitution of Koshihikari segments. QTLs for cellulose density were estimated on chromosomes 1, 3 and 5 by substitution of Koshihikari segments. For hemicellulose, QTL on chromosome 3 showed that hemicellulose density decreased by the substitution of Koshihikari segment. However, hemicellulose densities on chromosomes 5, 8 and 11 showed the opposite effects. The QTLs for hemicellulose, cellulose, and hollocelulose densities identified on chromosome 5 overlapped with that for bending stress, indicating the positive effect of Koshihikari segment on increasing bending stress. These results suggest that some QTLs for the densities of cell wall materials contribute to increasing bending stress and Young's modulus, and could be utilized to improve the lodging resistance for both types of breaking and bending in rice varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.