• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.479-485
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• 2002

This study was conducted in order to elucidate the effects of nitrogen level and split application method, and shading treatment during reproductive stage on sink formation. Japonica variety Choocheongbyeo and Hwaseongbyeo and indica$\times$japonica cross type variety Nampoongbyeo were used. Five levels (6 to 30 kg/10a at 6 kg/10a interval) of nitrogen fertilization, and two split application methods (50-25-25% and 30-30-40% as basaltillering-panicle fertilizer) for each nitrogen treatment were applied. In addition shading treatments (shading rate, 65%) were performed for N 12 kg/10a and 24 kg/10a plot. Shading were applied for 30 days from panicle initiation to heading, 15 days from panicle initiation and 15days before heading. Panicle per square meter, and primary rachis branches per panicle and differentiated number of secondary branch per panicle increased according as applied nitrogen amount increased up to 18 to 24 kg/10a, and there was no significant difference between two nitrogen application methods. Primary rachis branch and secondary branch per square meter also increased according as the amount of applied nitrogen increase up to 18 to 24 kg/10a, and there was no significant difference between nitrogen application methods. Panicle per square meter and primary rachis branch per panicle were significantly decreased due to shading treatments only in Choochengbyeo. In all varieties, shading reduced secondary rachis branch per panicle significantly and the reduction was greatest in 30 days shading during reproductive stage. Spikelets per square meter increased according as the amount of applied nitrogen increases up to 18 to 24kg/10a, but showed no move increase above this nitrogen application level. Significant difference was not shown between nitrogen split methods. Spikelets per square meter also decreased significantly due to shading treatment during reproductive stage, showing the greatest reduction by 30 days shading during reproductive stage, and the least by 15 days shading during booting stage. The variation of spikelets per square meter was influenced greatest by the variation of panicles per square meter and spikelets per secondary rachis branch.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.3
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• pp.51-60
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• 2003

In the radical char]go of the business environments that the existing facilities can not guarantee the business-frosts anymore, enterprises have been importing ERP system. In Korea, Sam-sung Electronics did it for the first tin in the latter half of 1994 and other enterprises succeeded. Currently, government and public enterprises as well as most of the large enterprises are employing ERP system to sharpen the competitiveness and to win the business transparency. On the other hand, it is harder for small and medium enterprises shaded by the large enterprises to be well-equipped with information system such as ERP, because they have already suffered from chronic financial difficulties and shortage of many resources. Most of all, they prefer the short-term project that does not need much tine for them to make decisions and to carry out fully. Grounded on the above factors, in this work, I suggest the suitable ERP model for the small and medium enterprises and the successful importing process of ERP, which is derived from the previous researches made by other masters' thesis. If necessary information and human resources are interchanged pertinently between local education institute and small and medium enterprise, the latter could not only deal with the confronted difficulties successfully inside and outside but attain the goal of being proficient in up-to-minute high technology. Besides, giving the students the opportunity of researching into the practice of the business they have not ever known, local universities could help their students accumulate knowledges and acquire ideas which could not be achieved in pure academic studies. When the above-mentioned procedure is over, the students might get the intellectual faculty to ponder on the future more concretely and enter a profession more carefully. In the result, we would raise up the percentage of the employment among the graduates. And active participation of university professors is the last important factor that assists the small and medium enterprises for introducing ERP system successfully. Their scholarly attainments play an important role in strengthening local economy and make the business competitiveness balanced between the capital and the local economy.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.36-43
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• 1985

This study was conducted to find out the consumptive use of irrigated water for calculation of a duty of water in paddy rice. Tall statured Japonica rice variety is Jinju(late). Short statured Tongil varities-Taebaek(early) and Pungsan(medium) were planted on the experimental farm of kyungpook National University in 1983. The results obtained in this study were as follows : 1. The average temperature of the underwater surface was $27.1^{\circ}C$ and the maximum was recorded at beginning of the August. 2. The evapotranspiration was gradually increased after transplanting and showed the peak from booting to heading stage of rice varieties. The average evapotranspiration through the whole growing period was 8. 43mm/day(Jinju) for tall statured Japonica variety, and 7.78mm/day(Taebaek), 7.71mm/day(Pungsan) for short statured Tongil varieties. 3. The ratio of evapotranspiration to pan-evaporation through the whole growing period was 1.71 for Japonica variety and 1.55 for Tongil varieties. 4. K-value in Blaney & Criddle formula was 1.41 for Japonica variety and 1.30 for Tongil varieties. Coefficient consumptive use of water (Kc-value) was 1.40 for Japonica variety and 1.27 for Tongil varieties. 5. It appeared that the water consumption in the 6, 8 cm pot is more than that of 2, 4 cm pot but the number of panicle of the 6, 8 cm pot is somewhat less than that of 2, 4 cm pot. The deeper water level is the less tiller became. It is consindered that 2 cm pot is more profitable than the others.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.248-262
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• 1987

This experiment was conducted to study plant characteristics and dry matter production of several rice varieties. The results are summarized as follows. 1. Culm length was gradually shortened as varieties were improved and showed significant decrease in Japonica X Indica hybrids. 2. Panicle length seems to be shortened as varieties changed from group I to group III. However, varieties in group IV had longer panicle length in spite of shortening tendency in other groups. 3. Leaf blade length was decreased as varieties improved, but leaf blade width was increased. 4. Panicle exertion showed significant decrease as varieties improved. 5. Number of panicles per square meter among Japonica varieties was gradually increased and similar to the number of spikelets per panicle. Number of spikelets on Indica X Japonica hybrids were higher than Japonica varieties, whereas 1,000 kernel weight was slightly decreased. 6. Dry weight of leaf sheath and culm, and leaf blade was highest at the time of heading and the weight of panicle showed significant increase between 10 and 20 days after heading. 7. The maximum crop growth ratios of leaf blade, stem and panicles were attadined at the stage of heading, booting and milking, respectively. 8. The distribution ratio of dry matter was higher in leaf blade than in stem at the tillering stage. At the heading stage, the distribution ratio of dry matter was higher in order of culm, leaf blade and panicle. At the maturing stage, the ratio was higher in order of panicle, stem and laf blade. 9. Correlation coefficients among grain yield, harvest index, and biological yield were all significant and they were positive.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.61-70
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• 2004

Silage additives are needed to increase the quality of whole crop rice silage which seldom produce without the additives due to both high pH and butyric acid concentrations. Little information, however, is available about the silage fermentation of whole crop rice added with silage additives in Korea. This study was conducted to determine the optimum levels of silage additives by evaluating the effects of latic acid bacteria (LAB) and formic acid concentrations on the silage quality of whole crop rice harvested at different mature stages. Field study was established early in May until October 7th on a rice field at Yupori, Sinbuk-yeup, Chunchon, Kangwon-Do. "Ilpum" mutant rice was harvested at six different mature stages; booting stage (17 Aug.), milk-ripe stage (27 Aug.), dough stage (7 Sep.), yellow ripe stage (17 Sep.), dead ripe stage (27 Sep.) and full ripe stage (7 Oct.). Each sample was ensiled in three different ways; with 1) LAB (0.05, 0.1 and 0.2% of sample wt), 2) formic acids (0.2, 0.3 and 0.4% of sample wt.) and 3) no additive. The additive levels did not affect dry matter content, crude protein, fiber and total digestable neutriant concentrations at all stages. Addition of additives significantly decreased the silage pH and butyric acid concentrations which tended to be more decreased with higher levels of additives. Latic acid concentrations were higher with the use of additives, especially with LAB. The lower concentrations of ammonia-N were observed in additive treatments at all stages, but the concentrations of ammonia-N did not differ according to the additve levels after yellow ripe stage (0.69, 0.60 and 0.71% of DM in 0.05, 01 and 0.2% of LAB, respectively; 0.64 0.59 and 0.75% of DM in 0.2, 0.3 and 0.4% of formic acid, respectively). These results indicate that the optimum addition levels of LAB and formic acid are 0.5∼0.1% and 0.2∼0.3%, respectively, on which the high quality of rice whole crop silage was produced. produced.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.319-325
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• 2022

Triticale forage has the highest yield of all winter forage crops, including rye, and a cold tolerance within an average low temperature of -10℃ in January. Therefore, this study analyzed the effects of sowing and harvesting times on the feed value and functional components of triticale to optimize the use and supply of triticale as livestock fee Room temperature' can vary widely with climate, season, and time of day. In order to clearly state the conditions of the study in a manner that facilitates replication by other researchers, please consider using an approximate temperature range instead. Seeds of the triticale 'Joseong' were sown during the fall of 2021 (October 20th) and spring of 2022 (March 7th). The triticale was harvested at the following growth stages: seedling stage, booting stage, heading stage, 10 days after heading, and 20 days after heading. The moisture content of each harvested triticale was adjusted to approximately 60%, and the triticale was fermented for silage for 40 days at ambient temperature under anaerobic conditions. We measured the pH and organic acid content of each silage to determine the feed value and functional component. The lactic acid content of the triticale silage harvested at the seedling stage sown in both fall and spring (1.61%, 1.63%) was the highest among all the silages. The octacosanol content in the silages of both fall-sown and spring-sown triticale harvested at the seedling stage (0.38, 0.27 mg/ml) was the highest. Overall, the results revealed that harvesting time had a greater impact on the feed value and functional components of triticale silage than sowing time.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.356-369
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• 1985

In Korea, inevitable researches for the blast control exactly started from 1927 by the organization of Office of Rural Development with the local extensive outbreak of panicle blast at Jeonlla Buk-Do Province in 1926. At present, the rice blast is still one of the most destructive and widespread diseases in spite of considerable contributions by rice scientists, particularly plant pathologists during last 55 years in Korea. Rice blast control and management are very difficult because of the marked variability in pathogenicity of the blast fungus. From the results obtained through the disease surveys during last 70 years, different 3 prevalence type of blast such as bimodal leaf-blast type, bimodal panicle-blast type and bimodal continual blast type were recognized. In generally speaking, pattern of blast outbreak is said to be characterized by severe outbreak of panicle blast after slight outbreak of leaf blast with discontinuity between leaf and panicle blast. So we have to pay much attention for successful management of panicle blast giving direct influence to rice yield. Main factors induce blast epidemic were pointed out to be breakdown of the disease resistance, nutritional unbalance such as excess application of nitrogen, delay of transplantation and longspell of rain fall by extensive surveys and researches on blast during last 70 years in Korea. The fact some of Japonica varieties such as Kokuryomiyako, Tamanishiki, Ginbozu and Pungok belong to varietal group A had been cultivated with extensive acrage over 30 years in this country should be mentioned by Korean rice scientists. Differences in field resistance between varieties in the same group are detectable and apparently small but sometimes epidemiologically significant differential effects may be found out in case of blast. Much more attention should be payed to accumulate the knowledges on field resistance for successful management of blast. Excess application of nitrogen is more effective to outbreak of panicle blast than that of leaf blast of IR varieties. In comparatively low level application of nitrogen infection rate of panicle blast of IR varieties is considerably high. Low temperature effects on outbreak of blast is very great. It results in remarkable increase of the inoculum potential on the leaf lesions and infection of panicle blast in leaf sheathes of IR varieties during the booting stage. In economic point of view, it is concluded that 5 times sprays of effective fungicides including 3 times before and 2 times after heading is good enough to control blast. We have experienced no one of control measures for blast is superior to all others. The integrated control measures was established as guideline of blast control around 1950 in Korea. This guideline must be helpful for rice growers as long as rice growing continue.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.123-133
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• 1992

This study was conducted to clarify progressed changes of plant types and the effects of the physiological and ecological components on improving ideotype of winter wheat. 12 wheat varieties were planted at the experimental farm of Wheat and Barley Research Institute in Suwon in 1990. As results of intensive wheat breeding for early maturity since 1959, heading, flowering and maturing dates have been shortened by 17, 15 and 14 dagys, respectively. The shortened days from sowing to heading and from heading to flowering contributed to the early maturity to improved. Physiological factors associated with heading time of wheat could be reprsented by growth habit, photoperiod responses, earliness in narrow sense and winter hardiness. For improving an early maturity of winter wheat, it would desired to maintain some degree of winter habit(III-IV), and recombination of more insensitivity to short day length and more shortened earliness in narrow sense than that of Saemil and Chugoku 81, and higher degree of winter hardiness. For improving the early maturity the more effective way must be of shortened days from sowing to heading, and days from flowering to maturity than days from heading to flowering. Ideotype of wheat will be desired to recombine two semi-dwarf genes with erect plant type being about 70-80cm, less stem elongation by late spring, long spike and many grains per spikelet. Average spike weight ratio was about 45-49% in high-yielding varieties, stem fresh weight was lighter, but spike fresh weight was heavier in new one while leaf fresh weight was similar to each other during the maturing periods. Average spike dry weight ratio was higher about 40～48%, and stem and leaf blade dry weights were lower in the newly bred varieties. Stem dry weight was heavier than spike or leaf dry weight in the old varieties of Yungkwang, Jangwang and Jinkwang. Leaf area index for the varieties showed normal distribution curve as the maximum point in booting stage. The maximum point of this curve come in early maturing wheat, and late in old one. The maximum points of LAI were 6.4～6.8 in the high-yielding varieties. Totals of LAI in each period investigated of old one were higher than those of newly bred being 24.6～28.8. Chlorophyll content of the high-yielding varieties of Chokwang, Geurumil and Saemil as higher than that of the old varieties Jangkwang, Jinkwang, Wonkwang and Sinkwang from regrowing period to April 21. after then slightly and even after heading. Net assimilation rate (NAR) was higher in high-yielding varieties with good plant type, and lower in old ones. Grain yield of the newly released varieties increased rapidly but slowly in the old ones. Change in water content of grain at the growing stage in newly bred was lower than that of the old bred. Diminishing rate of water content of grain in establishment per day was 1.2% average that of the old varieties including Yungkwang was 1.5%, and those of the newly bred including Chokwang were 0.9～1.1%. Chokwang, Naemil, and Saemil were the highest-yielding varieties of the Korean cultivars. Yields were increased by spikes per m$^2$, grain weight for the varieties bred in Suwon, and by spikes per m$^2$ for the varieties bred in Milyang.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.1-31
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• 1981

Experiments were conducted to investigate rice varietal response to low water and air temperatures at different growth stages from 1975 to 1980 in a phytotron in Suweon and in a cold water nursery in Chooncheon. Germination ability, seedling growth, sterility of laspikelets, panicle exertion, discoloration of leaves, and delay of heading of recently developed indica/japonica cross(I/J), japonica, and indica varieties at low air temperature or cold water were compared to those at normal temperature or natural conditions. The results are summarized as follows: 1. Practically acceptable germination rate of 70% was obtained in 10 days after initiation of germination test at 15\circ_C for japonica varieties, but 15 days for IxJ varieties. Varietal differences in germination ability at suboptimal temperature was greatest at 16\circ_C for 6 days. 2. Cold injury of rice seedlings was most severe at the 3.0-and 3.5-leaf stage and it was reduced as growth stage advanced. A significant positive correlation was observed between cold injury at 3-leaf stage and 6-leaf stage. 3. At day/night temperatures of 15/10\circ_C seedlings of both japonica and I/J varieties were dead in 42 days. At 20/15\circ_C japonica varieties produced tillers actively, but tillering of I/J varieties was retarded a little. At 25/15\circ_C, both japonica and I/J varieties produced tillers most actively. Increase in plant height was proportional to the increase in all varieties. 4. In I/J varieties the number of differentiated panicle rachis branches and spikelets was reduced at a day-night temperature of 20-15\circ_C compared to 25-20 or 30-25\circ_C, but not in japonica varieties although panicle exertion was retarded at 20-15\circ_C. The number of spikelets was not correlated with the number of primary rachis branches, but positively correlated with that of secondary rachis branches. 5. Heading of rice varieties treated with 15\circ_C air temperature at meiotic stage was delayed compared to that at tillering stage by 1-3 days and heading was delayed as duration of low temperature treatment increased. 6. At cold water treatment of 17\circ_C from tillering to heading stage, heading of japonica, I/J, and cold tolerant indica varieties was delayed 2-6, 3-9, and 4-5 days, respectively, Growth stage sensitive to delay of heading delay at water treatment were tillering stage, meiotic stage, and booting tage in that order, delay of heading was greater in indica corssed japonica(Suweon 264), japonica(Suweon 235), and cold tolerant indica(Lengkwang) varieties in that order. Delay of heading due to cold water treatment was positively correlated with culm length reduction and spikelet sterility. 7. Elongation of culms and exertion of panicles of rice varieties treated with low air temperature 17\circ_C. Culm length reduction rate of tall varieties was lower than that of short statured varieties at low temperature. Panicle exertion was most severaly retarded with low temperature treatment at heading stage. Generally, retardation of panicle exertion of 1/1 varieties was more severe than that of japonica varieties at low temperature. There was a positive correlation between panicle exertion and culm length at low temperature. 8. The number of panicles was increased with cold water treatment at tillering stage, but reduced at meiotic stage. As time of cold water treatment was conducted at earlier growth stage, culm length was shorter and panicle exertion poorer. 9. Sterility of all rice varieties was negligible at 17\circ_C for three days but 30.3-85.2% of strility was observed for nine-day treatment at 17\circ_C. Among the tested varieties, sterility of Suweon 264 and Milyang 42 was highest and that of Suweon 290 and Suweon 287 was lowest. The most sensitive growth stage to low temperature induced sterility was from 15 to 5 days before heading. There was positive correlation between sterility of rice plants treated with low temperature at meiotic and heading stage. 10. Percentage of spikelet sterility was greatest at cold water treatment at meiotic stage (auricle distance -15～-10cm) and it was higher in 1/1 (Suweon 264, Joseng tongil), japonica (Nongbaek, Towada), and cold tolerance indica(Lengkwang) varieties in the order. Level of cold water and position of young-ear affected on the sterility of varieties at meiotic stage; percentage of spikelet sterility of variety, Lengkwang, of which young-ear was located above the cold water level was high, but that of short statured variety, Suweon 264, of which young-ear was located in the cold water was lower. 11. Percentage of ripened grains was not reducted at 15\circ_C air temperature for three days at full heading stage in all varieties. However, at six-day low temperature treatment Suweon 287, Suweon 264 showed percentage of ripended grains lower than 60%, but at nine-day low temperature treatment all varieties showed percentage of ripened grains lower than 60%. Low temperature treatment of 17\circ_C from 10 days after heading for 20 days did not affect on the ripening of all varieties. 12. Uptake of nitrogen, phosphorous, potassium, calcium, and magnesium in whole plants was higher at average air temperature of 25\circ_C, but concentration of the elements was lower compared to those at 19\circ_C. However, both total uptake and concentration of manganese were higher at 19\circ_C compared to 25\circ_C. 13. Higher application of nitrogen, phosphorus, silicate, and compost increased yield of rice due to increased number of panicles and spike let fertility in cold water irrigated paddy.