• Journal of Biosystems Engineering
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• v.7 no.1
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• pp.17-32
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• 1982

The binders introduced in Korea were originally designed to be used for Japonica-type varieties which have relatively long stem and are highly resistant to shattering. In order to use it for Tongil varieties which are short and easy to be shattered, mechanical modifications are necessary to reduce a grain loss incurred during binder operation. This study was intended to investigate analytically and experimentally the major sources of grain losses caused by three kinds of binders now introduced in Korea. Actual modification for each of three binders was done and experimentally compared to see if any improvement on grain loss was achieved. The results obtained in this study are summarized as follows; 1. It was required that the power transmission of binder should have a shifting mechanism so that velocities of pick-up and traveling units could be changed independently as desired according to the Japonica-type and Tongil varieties. In other words, the desired velocity of traveling unit should be obtained by shifting the transmission and the velocity of pick-up unit should be selected by reaping clutch according to the variety independent of the velocity of traveling unit as shown in Fig. 6. 2. To reduce grain loss it was desired that the moving parts of the pick-up unit should have the lowest possible velocities in harvesting Tongil varieties, unless the reduction of the speed be hindered the conveyance of the material. Based on the study, it was concluded that the velocities of pick-up unit be reduced by about 35% of those of the existing units. 3. It was found that the lug at the upper rotating section of pick-up case gave a severe impact on the ears of rice to increase grain loss. The optimum design of pick-up case to protect the ears from the protruding part of the lug was recommended by the result of analysis of the trajectory of the end-point of lug at the position. 4. It was proved analytically and experimentally that pick-up unit at the lower-rotating part was the other important source of grain loss in pick-up and divider assembly. In order to reduce a grain loss incurred by lugs at their lower-rotating section, it was suggested to improve it by (1) widening the space between right and left lower-rotating section, (2) shortening the length of lugs, (3) enlargement of the angle between the pick-up case and ground-level, and (4) attaching guard to right and left dividers so that the rotating lug could not give a high impact to the paddy hill. 5. Pick-up and divider assembly of the original binder of three models studied was modified according to the suggestions that were given by the preliminary study. Field test showed that the modified binders were able to reduce grain losses by about 0.4-0.7 percentage points compared to those without modification.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.431-435
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• 1985

Nine hybrid rices crossed between Korean cytoplasmic-genetic male sterile rices having the WA cytoplasm and the Korean restorer lines or varieties, HR1619A/Nampungbyeo, HR1619A/Gayabyeo, HR1619A/Line234, TongilA/Nampungbyeo, TongilA/Cheongcheongbyeo, Suwon 296A/Line 209, Suwon 296A/Line 237, Suwon 296A/Line 252 and Line 201A/Line 234, and their parents were grown at Yeungnam University in 1984. The rough rice yield of the hybrids Line 201A/Line 234, TongilA/Nampungbyeo and HR1619A/Nampungbyeo were 939, 927 and 900 Kg/10a respectively. The heterosis(F$_1$/Midparent) of the above three hybrids was 40%, 20% and 19%, the heterobeltiosis(F$_1$/Better parent) was 36%, 17% and 10%, and the standard heterosis (F$_1$/Standard variety, Cheongcheongbyeo) was 19%, 17% and 14% respectively. The hybrids HR1619A/ Gayabyeo and Suwon 296A/Line 237 showed negative heterosis in grain yield. Significant heterobeltiosis for grain number per panicle was found while less or no heterobeltiosis was observed in panicle number per hill, 1000-grain weight and grain fertility. The bacterial leaf blight disease reaction of the hybrids tested was almost the same as that of one parent at least. The amylose content of the hybrids was medium to low the same as their parents. The protein content and alkali digestion value of the hybrids were almost the same as their parents.

• Applied Biological Chemistry
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• v.22 no.3
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• pp.181-189
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• 1979

In order to establish fertilizing technique for the increase of grain yield and its stability, the total absorbed amount of nutrients and nutritional status of rice plants at different growth stages were studied with respect to the nutrient contents and its relation to grain yield and yield components. This experiment was carried at three different level of nitrogen fertilization; two different seeding and transplanting times, and eight cultivars including both Japonica-and Tongil-type. The results of a part of these experiments are summarized as fallows: 1. The culm length tended to Increase with increasing fertilizer amount, but no significant difference between ordinary and heavy fertilization was observed in Tongil-type cultivars. 2. The panicle length was some what longer in ordinary and heavy fertilization than non-fertilization. 3. As the N-fertilizer level increases, the number of panicles per plant increased with higher response in Japonica-type cultivars than in Tongil-type cultivars. 4. The number of grains per panicle increased significantly in ordinary and heavy fertilization, compared to non-fertilization, but the difference in grain number per panicle among fertilizer treatment was smaller in Japonica-type cultivars than Tongil-type. 5. The 1,000 grains weight showed no significant difference among fertilization levels in ordinary transplanting, but indicated gradual decreasing tendency as the transplanting delayed. 6. In percentage of ripeness, there was no significant difference in ordinary transplanting, but hightly significant in late transplanting among N-fertilization levels and cultivars. 7. In yield, highly significant difference was shown among N-fertilizer levels and cultivars In Tongil-type variety, higher yield was obtained in ordinary fertilization than heavy fertilization. 8. The straw weight showed the tendency to increase in higher nitrogen level, but no significant difference between ordinaly and heavy fertilization was observed in Tonsil-type cultivars.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.26-33
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• 1977

We have studied the responce of nitrogen on the newly bred varieties, Yusin and Milyang #23, and the effects of defoliation at maturing stage on the rate of ripened grains under different nitrogen levels. The results obtained are summarized as follows : 1. Milyang #23 as well as Tongil was found to be highly nitrogen responsive variety and showed good grain maturing percentage. The number of grain per unit area affected the total yield under the high levels of nitrogen application. The variety, Yusin, was less responsive to nitrogen and had also less leaf area than other varieties under the high level of nitrogen application. Yusin also seemed to have low maturing percentage due to unbalanced ratio between photosynthetic area and size of storage. 2. The low internodes and leaf blade of Yusin and Milyang #15 were grown too much under high levels of nitrogen and these caused more lodging and less light penetration in pant canopy. 3. The effects of defoliation at maturing stage on yield was high under the high levels of nitrogen application, especially when defoliation was done early stage of maturing. The effects of defoliation appeared to be greates in Tongil than in Milyang #15.

• Journal of Biosystems Engineering
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• v.9 no.1
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• pp.11-21
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• 1984

This study was intended to analyze the dynamic force system which induced the shattering of paddy grains. A model to predict the shattering of paddy grains was developed, and physical quantities, such as mass distribution and rigidity of rice plant, needed for evaluating the minimum shattering forces were also measured. Under the assumption that rice plant right before harvesting is a vibratory system, the mathematical model of the vibratory system was developed and solved with the varied conditions of forcing functions. The results of the study were summarized as follows: 1. The shattering of grain occurred at the abscission layer of grain by the bending moments resulted from the impact force due to the collision of panicles of rice plant. 2. The vibratory model developed for milyang 23 rice variety was analyzed to give the natural frequencies of 7-9 Hz, which were closely related with the excitation frequencies of 4-10 Hz caused by various machine parts besides engine. Thus, avoiding the resonance should be taken into consideration in the design of the harvesting machinery. 3. It was analyzed to predict the lowest frequency that could develop the shattering when the excitation force was applied to the lower end of stem. The lowest frequency for the Milyang 23 rice variety ranged from 8.33 Hz to 11.66 Hz as the amplitude varied from 1 cm to 2.5 cm. 4. The degree of shattering depended upon the magnitude of the impact force and its application point. For Milyang 23 rice variety, the minimum impact force developing the shattering was $5g_f$ when it was applied at 1 cm above the lower end of stern and $1g_f$ when applied at 5 cm above the lower end of stem. 5. The minimum colliding velocity of the panicle, when it was on the ground that would just develop the shattering, was given as follows, $$V=\sqrt{\frac{K_t}{m_g}{\cdot}{{\phi}^2}}$$ where V : The colliding velocity of the panicle against ground to cause the shatteering of rice grain. (cm/sec) $K_t$ : The minimum spring constant for bending at the abscission layer of grain. (dyne-cm/rad) ${\phi}$ : The minimum shattering angle of grain (rad) $m_g$ : The maximum mass of grain. (g).

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.88-99
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• 1978

In this study, rice harvesting systems suitable to Korean situations and the optimum timing of these systems were determined, respectively, based on experimentally determined factors such as filed yield and the milling quantity and quality measured at various levels of the grain moisture content at harvest. Rice varieties used for the experiment were the AKIBARE (Japonica-type) and the SUWEON 251 (high yielding TONGIL sister-line variety), The harvesting systems studied by the experimental work of this study were traditional system with both the wet material and dry-material threshing system by use of binder with both the dry-material and wet-material threshings, and system by use of combine. Grain samples were taken from final products of the paddy rice harvested from the experiment a fields for each system to measure the recovery rates of the milled rice. The results may be summarized as follows; 1. The milling recovery rate of the AKIBARE variety had highest value within the range of the grain moisture at harvest, showing from 21 to 26 percent. The head-rice recovery for the same variety was a little greater in the wet-material threshing than in the dry-material threshing , higher values of which , were 20 to 25 percent , seen within the range of grain moisture at harvest regardless of the harvesting systems tested. 2. The milling recovery of the SUWEON 251 , when tested for different harvesting systems and harvesting grain moisture, did not show a statistically significant different. In contrast , head-rice recovery for the systems operated by the wet-material threshing was much greater than that by the -material threshing. The difference of the recoveries between these systems range from 2.6 to 4.7 percent. 3. An assessment of the optimum period of -harvest timing for each of the harve\ulcornersting systems tested were made bJ.sed on (a) the maximum total milled-rise yield and (b) the percentage reduction in the total milled-rice yield due to untimely harvest operations. The optimum period determined are: 23-19% for the ATD, AC, STD, SBW, STW systems, 25-21% for the ATW ani ABW systems, and 27-18% for the ABD, SBD, and SC systems, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.12-40
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• 1983

Heading behaviour of native japonica (GI) and Japanese varieties (GII) grown during 1910-1920s were thermo-sensitive, home bred varieties during 1930s (GIII) - 1950s (GIV) were photo-sensitive and semi-dwarf indica derived varieties released since 1971 (GV) were controlled by basic vegetative phase. Number of leaves on main culm was increased with varietal improvement and culm length was gradually shortened as variety improved. GV variety had the shortest plant height among the groups. The first internode length was about 30cm in all groups and difference of 2nd-4th internode length was caused shortening the culm length. Panicle length and diameter of panicle neck were shortened and became thinner as variety developed from GI to GIV, however, GV had longer panicle and thick panicle neck, respectively. Number of panicles/hill and straw weight/hill increased and became heavier as variety improve from GI to GIV but GV had moderate number of panicle/hill and relatively light straw weight. Number of spikelet/panicle has been reduced with varietal improvement but GV had the biggest number. Grain yield/hill also increased as variety improved, however, it was decreased as transplanting season postponed and GV had shown the most sensitive difference. Top dry matter weight at heading stage and at 20 days after heading (20 DAH) had no difference among the groups except GI which was the smallest. Average grain weight at 20 DAH was heavier in the order of GI > GII, GV > GIV > GIII. It had a little variation in GI & GII while that of other variety group showed significant decrease as transplanting delayed. Harvest index (HI) of GV was the highest at 54% for the earlier transplanting and GIII had the lowest HI. Difference of HI became conspicuous for the later transplanting, the varieties bred later had the lower HI when transplanting of rice delayed. At the earliest transplanting applied (May 15), the grain yield was higher in the order of GI > GIV > GIII > GII > GI, however, that of Tongil type variety (GV) was the lowest for the latest transplanting (June 29). Interrelationship among the agronomical characteristics and grain yield was discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.1-7
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• 1980

In 1976, a newly released rice variety, Yushin, was planted in 300,000 ha of the 533,000 ha of cultivated total hecterage with new rice varieties. High productivity and quality were achieved by farmers around country. However, the wilting phenomena of Yushin occured in some regions where were employed poor cultural management, and flowed sewage into the paddy field from industrial factories. This study was identified some factors for the wilting phenomena of Yushin rice variety in morphological and physiological aspects. The Yushin variety showed greater internode elongation on low part of the stems that close related to lodge at heavier nitrogen levels, excessive number of spikelets per unit leaf blade weight i.e. higher sink/source ratio, and greater consumption of respiratory substrate by increased respiration rate of rice plant as compared with those of Tongil rice variety. In physilogical aspects, the Yushin variety was significantly declined root development and root activities under heavy nitrogen conditions. Yushin rice variety was decreased $K_2$O/N ratio, carbohydrate content in stem of rice plant, and physiological root activities specially in low light intensity, 50% light interception plots. Therefore, above factors were mainly promoted the wilting phenomena of Yushin rice variety.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.2
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• pp.35-41
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• 1983

This research is mainly to deal with the effects of submergence treatment on the grain yields of two rice plants, local variety, "Akibare" and Tongil line variety, "Milyang 23". The results obtained are summarized as follows. 1. According to the rice products of each plot the grain yield index was smallest in the plot treated at the early heading stage. The index of the next order became smaller in order of late flowering stage, late reduction division stage, milk ripe stage and dough ripe stage etc. The submerged stage at which the damages were smallest was tillering stage. Under the condition of two thirds or one third submerged depth of plant height, few differences in the grain yield index between Milyang 23 and Akibare was found, but except rooting stage, the damages of milyang 23 by whole submergence during growing period were mostly greater than those of Akibare. Especially the grain yield index of early heading stage at which the damages by whole submergence was most serious showed 45 percentage for one day submergence, 31 percentage for 3 days and 0.7 percentage for 7 days in Akibare plots, and 26.7% percentage for one day submergence, 7.9 percentage for 3 days and none for 7 days in Milyang 23 plots. 2. All the factors such as submerged stage, submerged depth and submerged period in this experimental test were highly recognized significance. The factors of the submerged depth and duration influenced on greater damages than the others. According to the difference in grain yield between plots, the larger the submerged depth and duration were, the larger the significant difference appeared. And between the treated levels at other submerged stages except both early tillering stage and most active tillering stage, the significance in the differences in grain yield was recognized, while only the submergence at early heading stage showed the most serious damages. 3. The decreased rate of grain yield for one day submergence at early heading stage indicated that in case of whole submergence of plant height it was 73 percentage in Milyang 23 plot and 55 percentage in Akibare plot, and in the event of two thirds and one third submergences of it, 20 percentage and 10 percentage in both Mulyang 23 and Akibare plots respectively. Therefore, the current criteria for planning project that restricted allowable submergence duration of more than 30cm submerged depth to 24 hours, should be amended not to exceed the submerged depth of 60cm when the duration of more than allowable submerged depth of 30cm will be limited to 24 hours, or within the limits of 12 hour submerged duration for locai variety and of less than 12 hour duration for Tong-illine variety as long as possible in case that submerged depth will be allowed to more than 60cm depth.ore than 60cm depth.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.201-205
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• 2011

'Hangangchal 1' is a new glutinous rice cultivar of second generation Tongil-type with a mid-maturing ecotype that developed by the rice breeding team of Yeongnam Agricultural Research Institute (YARI), RDA. in 2006. This cultivar was derived from a cross between 'Hangangchal', a Tongil-type glutinous cultivar and 'YR8208-20', a high yield potential in 1986/1987 winter season. 'Hangangchal 1' was selected by pedigree and bulk breeding methods from $F_3$ to $F_6$ populations. A promising line, YR10498-8-1-3, was selected and designated as 'Milyang 167' in 1997. The local adaptability test of 'Milyang 167' was carried out at seven locations during 3 years in 1998, 2005, and 2006. It has tolerance to lodging with good canopy architecture as 87cm of culm length. This cultivar is resistant to bacterial blight $K_1$, $K_2$, and $K_3$ race, rice stripe virus, rice dwarf virus, and leaf blast disease. The milled rice endosperm of 'Hangangchal 1' is glutinous and its whiteness was almost similar compared to 'Shinseonchalbyeo'. The yield of milled rice of 'Hangangchal 1' was average 5.97 MT/ha at ordinary cultivation of 9 kg/10a N fertilizer level in local adaptability test. This cultivar would be adaptable to the mid and southern plain of Korea.