• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.1-6
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• 1994

Some physicochemical properties of sugary rices were comparatively analyzed with the original cultivars, using Hwachung su-1, su-2, and Nampung su lines bred in Seoul Nat'l Univ., and EM 5 bred in Kyushu Univ. Sugary rice grains were smaller in width and thickness, and the relative dry weight of 1000 grains of sugary rices ranged from 49% to 72%, compared to normal ones. No distinct starch granules were found in endosperm of sugary rices exposured by SEM, with structural variations between Hwachung su-1 and su-2 lines. Sugary rices showed the significant increases in sucrose, glucose and fructose content, especially much higher in sucrose content showing 5.84-8.79%, in comparison with the normal ones, 1.11∼2.65%. However, sucrose and total sugar content varied within sugary lines carrying the same sugary gene, and were significantly lower in Hwachung su-2. Sugary rices, except Hwachung su-1, showed the same or lower ADV and harder gel characteristics, compared to normal ones. Protein and lipid content were much higher in sugary rices, due to the increased relative proportion of aleurone layer in brown rice caused by thicker aleurone layer than in normal rices and the reduction of endosperm part. However, there were no remarkable changes in amino acid and fatty acid compositions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.3
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• pp.79-88
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• 1986

Drought occurs most frequently and severely around transplanting season of the rice plants in Korea. Shortage of water due to drought for the paddy fields often delays transplanting, and less often the rice plants are subjected to water stress after delayed transplanting. The present study aimed at quantification of the rice crop loss due to delayed transplanting, different inten3ity of water stress, and the combined effect of delay in transplanting followed by water stress for better use of limited water for irrigation under drought. The rice variety Chucheong, a japonica, and Nampung, an indica x japonica, were grown, transplanted to 1/200 a plastic pots, and subjected to different timing of transplanting and degree of water stress under a rainfall autosersing, sliding clear plastic roof facility with completely randomized arrangement of 5 replications. The results obtained are summarized as follows: 1.Twelve days or 22 days delay in transplanting without water stress reduced rice yield by 25% and 43% in the japonica variety, and by 15% and 60% in the indica x japonica variety. 2.The 10 days or 20 days water stress developed without irrigation after drainage in the rice plants transplanted at proper time lowered the water potential at the paddy soil 10cm deep to -4 bar, and -12 bar and caused rice yield reduction by 14%, and 45% in the japonica variety and by 8%, and 50% in the indica X japonica variety. 3.The 12 days delay in transplanting and 10 days or 20 days water stress reduced rice yield by 39% and 59% in the japonica variety, and by 38% and 52% in the indica x japonica variety. The 22 days delay in transplanting plus 10 days water stress caused yield reduction by 76%, i.e. meaningless yield, in both varieties. 4.The intermittent irrigation just to wet the soil body for 10 days after 10 days water stress without irrigation increased rece yield by 12 to 16% compared to the rice plants water stessed without irrigation continuously for 20 days in both varieties respectively. 5.The above results suggest strongly 1) to transplant the rice plants at proper .time even with some water stress rather than delay for sufficient water from later rainfall, and 2) to distribute insufficient irrigation water to broader area of transplanted rice with limited irrigation for better use of limited irrigation water. A greater sensitivity of japonica variety to a moderate water stress than the indica X japonica variety during initial rooting and tillering stage was noticed. To cope with frequent drought in rice culture, firstly the lasting time of transplanting without yield reduction should be clarified by region and variety, and secondly a scheme of rational distribution of limited water should be developed by region with better knowledge on the varietal distribution of limited water should be developed by region with better knowledge on the varietal responses to varying intensity of water stress.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.189-194
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• 2003

Rice seeds of 4 cultivars including Whachung-giant embryonic rice and Nampung-giant embryonic rice, as a group of the non-waxy rice cultivars, and Shinsunchal-giant embryonic rice and Whachungchal-giant embryonic rice, as that of the waxy rice cultivars, were germinated at $27^{\circ}C$ for 3 days to compare the changes in some physicochemical properties of the starch granules and the starch-hydrolysing enzyme activities during germination, respectively. ${\alpha}-Amylase$ activity of rices germinated for 3 days found to be higher than that of malt. Especially, Whachung-giant embryonic rice and Shinsunchal-giant embryonic rice were greater in activity than other rice cultivars and possessed the activities double that of malt. In contrast, ${\beta}-amylase$ of germinated rice found to be considerably less active than malt, although the giant embryonic rice group showed prevalent activity as compared o the normal rice group. With the starch granules, the amount of long glucose chains from amylose molecules were reduced in the non-waxy type giant embryonic rices, while the chain length increase was found in the waxy type giant embryonic rices. For the distribution profile of the glucose chain length from amylopectin molecules, we could observed that the chain length with DP (degree of polymerization) ranged 33 to 66 and 14 to 32 increased with the decreasing rate of that above 67 and below 13 regardless of starch waxiness. With non-waxy type of giant embryonic rices, susceptibility for glucoamylase were found to reduce along with germination, however, increase in susceptibility was observed with waxy rice types. In addition, we found the reduction in both initiation and termination temperature, and enthalpy for gelatinization.

• 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 Food Science and Technology
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• v.21 no.2
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• pp.262-268
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• 1989

The composition of glycolipid, phospholipid and fatty acid of brown rice, milled rice and bran were studied for four varieties of rice such as Nampung, Milyang # 23, Whasung and Jinhung. The content of esterified steryl glycosides(ESG) in glycolipids was the highest in the brown rice, milled rice and bran. Monogalactosyl diglycerides(MGDG) and steryl glycosides(SG) were the second highest. Of the phospholipids, phosphatidyl cholines(PC) + phosphatidyl serines(PS) were the next. Fatty acid composition of glycolipids were different from total lipids and neutral lipids in brown rice and milled rice. Palmitic acid content was very high and oleic acid content was low in glycolipids. The major fatty acid components of phospholipids in brown and milled rice were also palmitic, linoleic and oleic acid. In the bran, the major fatty acid classes were different from those of milled rice.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.696-701
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• 2003

Rice seeds of 4 cultivars including Whachung and Nampung, of the non-waxy rice cultivars, and Shinsunchalbyeo and Whachungchabyeo, of the waxy rice cultivars, were germinated at $27^{\circ}C$ for 3 days to compare the changes in some physico-chemical properties of the starch granules and the starch-hydrolysing enzyme activities during germination, respectively. With the starch granules, the amount of long glucose chains from amylose molecules were reduced in the non-waxy rices, while the chain length increased in the waxy rices. In the distribution profile of the glucose chain length from amylose molecules, we could observed that the chain length with DP (degree of polymerization) ranged 33 to 66 increased with the decreasing rate of the chain length with that above 130, regardless of the waxiness of rices. In addition, we observed that in contrast to a increase in chain length with DP ranged 14 to 33, the amount of short chains from A chain fraction decreased. Germination induced slight reduction in the polymerization rate of starch granules, and decrease in both initiation and termination temperatures for the gelatinization. ${\alpha}-Amylase$ activity of rices germinated for 3 days found to he higher than that of malt. Especially, the activity of Shinsunchalbyeo was revealed to be highest, about two fold higher than that of malt. In contrast, ${\beta}-amylase$ of the waxy rice found to be considerably less active than malt, although the waxy showed prevalent activity as compared to the non-waxy rices.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.540-544
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• 2001

The quality characteristics for brown rice flake were examined using eight kinds of brown rice cultivars such as Shinsunchalbyeo, Shinsunchal giant embryonic rice, Whachungchalbyeo, Whachungchal giant embryonic rice, Whachungbyeo, Whachung giant embryonic rice, Nampungbyeo, and Nampung giant embryonic rice. The qualities of grain such as the released reducing sugar, water absorption rate and hardness of grain are examined with different temperature and time at sedimentation in water and pressed grain-brown rice flake are prepared after sedimentation in $60^{\circ}C$ water for 5 hours. The brown rice flakes prepared from the giant embryonic type rice cultivars showed higher expansion volume, lower hardness, more crispness, longer bowl life time and better taste than that prepare from normal type rice cultivars, which showed the giant embryonic type rice cultivars were appropriate for brown rice flakes. Among the giant embryonic type rice cultivars, the glutinous rice varieties were better to prepared the brown rice flakes than its normal rice cultivars. The water absorption index of flakes tested were positively correlated with expansion volume and bowl life hardness. From tested sensory evaluation were shown to be negatively correlated with water absorption index. Among the tested cultivars, Shinsunchal giant embryonic and Wachungchal giant embryonic rice were most appropriate for brown rice flakes preparation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.7 no.1
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• pp.1-29
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• 1969

Experiments on rice concerning it s varieties, fertilization, seedling dates and herbicides have been conducted to determine the most desirable method of direct sowing cultivation on dry paddy field land in the middle part of Korea. The results obtained at the Office of Rural Development of Choongnam Province are as follows:. 1. Sixteen different derivatives from the main varieties of low land rice were cultivated on a dry paddy field by the direct sowing method; at the same time, a few varieties were tried adopting the common transplanting cultivation method. The yield and yield factors from these two groups were examined to give the following results: a) Compared to the common transplanting cultivation, the direct sowing method showed remarkably increased number of panicles while the number of flowers per panicle was shown to be significantly decreased. The maturing ratio was detected to be lowered. The yield horn them differed according to the different varieties : good yield was obtained from Hokwang while Norin ＃25 proved poor when compared with the common transplanting cultivation method. b) Among sixteen varieties tested, Sunsou, Norin ＃25, Jaigou, Hokwang, Palkueng and Gosi showed comparatively high yields, their yield being more than 325 kilograms per 10 Are, but Nampoong, Paldal, Nongkwang, Norin ＃29, Eunbangju ＃101 and Shiro gane showed less yield, their yield being less than 271 kilograms per 10 Are, the relations between the yield and the yield factors can be summarized as follows; Number of varieties and their rice yield. 1) The varieties which were great in the, number of panicles and high in yield=Jaigoun, Hokwang Palkueng and Gosi. 2) The varieties which were low in the number of panicles and high in yield=Sounsou and Norin ＃25. 3) The varieties which were great in the number of panicles and poor in yield=Eunbangju ＃101 and Sirogane. 4) The varieties which were poor in the number of panicles and poor in yield: Nampung, Paldal and Norin ＃29. Number of flowers per panicle and yield. 1) The varieties which were great in the number of flowers per panicle and high in yield: Sounsou, Norin ＃25 and Gosi. 2) The varieties which were poor in the number of flowers per panicle and high in yield ; Jaigoun, Hokwang and Palkueng. 3) The varieties which were great in the number of flowers per panicle and poor in yield: Paldal and Nampung. 4) The varieties which were poor in the number of flowers per panicle and poor in yield: Norin ＃29. Eunbangju ＃101 and Sirogane. Maturing ratio and yield. 1) The varieties which were high in the maturing ratio and high in yield: Jaigoun, Sounsou, Norin ＃25 and Palkueng. 2) The varieties which were low in the maturing ratio and high in yield: Hokwang and Gosi. 3) The varieties which were early maturing rat io and low in yield: Hokwang and Gosi. 4) The varieties which were late maturing ratio and poor in yield: Eunbangju ＃101, Nampungand Sirogane 1, 000 grain weight and yield. 1) The varieties which were heavy in 1, 000 grains weight and high in yield=Norin ＃25 and Hokwang. 2) The varieties which were light in 1, 000 grains weight and high in yield=Sounsou and Jaigoun. 3) The varieties which were heavy in 1, 000 grains weight and poor in yield=Nongkwang and Eunbanju. 4) The varieties which were light in 1, 000 grains weight and poor in yield=Norin ＃29 and Sirogane. 2. The experiment on fertilization showed that the most desirable amount to be given per 10 Are was 10 kilograms of Nitrogen, 5 kilograms of phosphate and 6 kilograms of potassium; and when the Nitrogen given exceeded 8 kilograms, its effect was better when given in amsll consecutive (split) amounts, while the maturing ratio and the number of the flowers per panicle increased when Nitrogen was given in large amount during the later stage of growth of rice. 3. The experiment on the date and amount of seedling showed that the tested variety, Sunsou gave the best results when planted on the days between 25 April and 10 May. Eight liters per 10 Are were preferable if planted early and 12 liters per 10 Are if planted late. The reason why the later planting gave a lower yield was that the number of flowers per panicle was fewer. 4. The experiment on the irrigation for rice with direct sowing cultivation immersed in water showed that it was the most satisfactory when irrigated on 25th June, 55 days after its seedling, its plot giving the best yield. The plots 10th June and 15th July showed just as good results. However, irrigated later, than 15th July it showed lower yields. 5. Compared to the yield of the plot controlled by the common method, the yield from the plots treated with chemical herbicide such as LOROX, TOK, PCP, SWEP, Mo-338 on dry condition soil seemed poorer, but significant difference was not found statistically. On the other hand in the case where chemical herbicides such as TOK, Mo-338, Stam F-34 or ORDRAM were used after irrigation, the yield from the ORDRAM and TOK treated plots did not show significant differences compared to the common hand weed controling method, but those treated with chemicals other than the above showed a lower yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.483-491
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• 2014

Double cropping system including paddy field soybean is widely adopted nationwide, due to rise in market price and its higher income than paddy field rice. Sowing date of soybean as a second crop is being delayed depending on first crop's growth period and harvesting time. Due to the increased temperature in October and delayed first frost date, soybean could be harvested without frost damage even in late-plating. Therefore, selection of soybean cultivar which is appropriate for this environment is very important. The effect of sowing date and genotype of soybean on growth and yield was investigated for three planting dates (June 20, July 5, and July 20) with ten cultivars developed for soy-pate production, to figure out plant development and yield pattern in delayed planting. As planting date is delayed, plant height and pod number was decreased and this pattern was more clearly detected in mid-late maturity cultivars. Hundred-seed weight did not show significant changes even in late planting, due to compensations between yield components. Yield reduction of July 20 in contrast to that of June 20 showed that Nampung (9.6%) showed the least yield decline. Maximum yield was achieved from Daepung, Taekwang, and Uram among other soybean cultivars in late planting. Shortening of growth period was strongly detected in reproductive stage while length of vegetative stage was regularly maintained in both early and mid-late maturity cultivars.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.71-89
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• 1988

This study was conducted to evaluate the effect of a growth retardant, Paclobutrazol on the growth, yield and its components. and physiological traits in peanut cv. Saeddle (early variety) and Nampung (medium variety). The results are summarized as follows : Main stem and branch length of both varieties were remarkably retarded at early growth stage application, but the retardation effect was reduced at late growth stage application. Number of branches was increased remarkably by treating 60ppm at 20days after seedling (DAS) in early variety. Lodging ill medium variety was not observed through growth period when 120ppm of Paclobutrazol was applied while lodging was not appeared between 40 DAS and 80 DAS in early variety. The numbers of riped pods in early variety was increased when application of 120ppm at 40 DAS was made while it was increased as application of 120ppm at 90 DAS in the medium variety. Cercospora leaf spot was reduced by spraying at 40 or 50 DAS regardless of concentration and varieties. Chlorophyll content and photosynthetic activity increased when paclobutrazol was applied during 40-60 DAS in early variety while these were observed at 90 DAS in medium variety. Seed weight tended to increase as paclobutrazol application was delayed. The ratio of pods to seeds was higher at 60ppm-40 DAS in early variety while it was higher at 120ppm-90 DAS in medium variety.