• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.278-283
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• 1984

Shearing characteristics of cornstalks were investigated under quasi-static conditions at various knife approach angles and shear angles in order to determine their importance to the cutting action of mowers. Corn variety used in this study was pioneer that was grown in the field of Chungnam National University. The results obtained were as follows: 1. The shearing process had two shearing stages in cornstalks, which was different from those of rice and other forage crops due to the hard crust. 2. Force and energy of shear were decreased progresively with height of the cornstalks. 3. The minimum shear force occured at shear angle of about $60^{\circ}$ and approach angle of about $10^{\circ}$ 4. The condition of minimum shear energy coincides with that of minimum shear force. 5. Effects of knife approach angles were more significant than those of shear angle for force and energy of shear.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.156-163
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• 2020

The purpose of this study was to select the wheat varieties, among 8 domestic cultivates, that are suitable, for use as grain feed at paddy fields in the Honam region. The seeds of wheat were sown and harvested in Wanju County. Among the wheat varieties, "Jojoong" was the earliest for its heading date on April 15, and it showed the earliest day for the maturing date on May 24. The heading date of "Baegjong" was the same as that for "Keumkang" on April 18, and the maturing date was one day later than that for "Keumkang" on May 29. But there was no significant difference of heading and maturing dates among the 8 wheat varieties. The lowest number of spikes/㎡ was 513/㎡ of "Goso", and the highest number of spikes/㎡ was 974/㎡ of "Chongwoo". The spikes/㎡ and yield of "Baegjon" was 542kg/10a and it was the highest yielding variety among the 8 wheat varieties. The chemical compositions of DM (dry matter) and CP (crude protein) on rumen digestibility were not significantly different among the 8 wheat varieties. Furthermore, rumen digestibility of DM and CP, and the nutrients value were slightly higher than those of corn. The domestic 8 wheat varieties for grain feed, with their high nutrient qualities, could eventually replace imported grain feed and wheat grain feed. These 8 varieties are cost-effective feed and paddy field fodder for livestock farmers.

• Journal of Plant Biotechnology
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• v.49 no.4
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• pp.356-361
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• 2022

Bacillus sp. is a useful strain for agriculture because it promotes plant growth and controls plant pathogens through a variety of mechanisms. In this study, we obtained a microbial preparation with a high number of viable cells by culturing newly isolated soil bacteria on an optimized medium. Subsequently, we applied this preparation to lettuce to enhance its growth and yield. First, B. amyloliquefaciens ISP-5 was isolated from soil. Next, optimization of culture medium was carried out using 5 L scale fermenters. When culturing B. amyloliquefaciens ISP-5 on this optimized medium, the number of viable cells was approximately 1000 times higher than that obtained from culturing on the commercial medium. Afterwards, the plant growth promotion properties of the ISP-5 strain were evaluated using lettuce as a test plant. Foliar spray treatment of lettuce was carried out by inoculating half the standard concentration suspension (0.5 × 10⁷ cfu/ml). As a result, leaf width increased by 8.6% and leaf length increased by 12.9% compared to the control group. Live weight also increased by 24.2% and dry weight by 23.9%. Considering the results from field test, B. amyloliquefaciens ISP-5 showed potential as a plant growth-promoting bacteria.

• Korean Journal of Breeding Science
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• v.51 no.2
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• pp.105-109
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• 2019

'Hwangdaok', a new maize F1 hybrid (Zea mays L.), was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2016. The high-yielding yellow dent hybrid named 'Hwangdaok' was obtained by crossing between two inbred lines, 'KS203' and 'KS190'. After advanced yield trial in Suwon in 2012, regional yield trial was subsequently carried out to evaluate the growth and yield of 'Hwangdaok' at three different locations from 2014 to 2016. The number of days to silking of 'Hwangdaok' is 76. The plant height is 262 cm and ear height ratio is 51%, which are similar to those of 'Jangdaok'. It has resistance to lodging. The number of ears per 100 plants is 95. The ear length is 21.3 cm and weight of 100 seeds is 34.7 g, similar to those of 'Jangdaok'. It has moderate resistance to southern leaf blight (Bipolaris maydis) and European corn borer (Ostrinia nubilalis). The grain yield (10 ton/ha) of 'Hwangdaok' is 6% higher than that of 'Jangdaok'. The seed production rate of 'Hwangdaok' is acceptable due to good synchronization of flowering period during crossing between the seed parent, KS203, and the pollen parent, KS190, in Yeongwol. F1 seed yield was 1.68 ton/ha. 'Hwangdaok' can be a suitable cultivar to plain areas in Korea. (Variety registration No. 7502).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.123-131
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• 1973

1. In order to evaluate the performance of the $F_2$ and $F_3$ generations of $F_1$ varietal crosses which in past trials yielded better than or as high as the recommended double-cross hybrids, eleven yellow and five white-endosperm $F_1$ varietal crosses, their $F_2$ and $F_3$ generations, and the parental open-pollinated varieties together with the standard double-cross hybrids were tested in performance trials in the 1963 wet and 1963-64 dry seasons. The former trials, however, failed due to a strong typhoon that damaged the crop. 2. Net hybrid vigor was highly manifested in grain yield in the $F_1$ varietal crosses, which on the average was 39.9 per cent of the mid-parent yields. Reduction in heterosis was 27.2 per cent in the $F_2$and 30.3 per cent in the $F_3$ generation, respectively. 3. A fairly high degree of reduction in yield occurred in the $F_2$ and $F_3$ generation. On the average, the $F_2$ generation decreased by 17.6 per cent and the $F_3$ by 20.7 per cent. The losses in two generations were exhibited in two levels; four crosses decreased by 10.9 per cent and twelve combinations by 22.0 per cent. The advanced generations of one yellow cross, Cuban Yellow Flint ${\times}$ Hawaiian Flinty Dent, and three white flint crosses, Bicol White Flint ${\times}$ Eto Blanco, College White Flint ${\times}$ Eto Blanco and Bicol White Flint ${\times}$ Nariono 330b, yielded as high as Philippine Hybrid No.1 and Philippine Hybrid No.4, respectively. 4. No significant differences in yield were obtained between the $F_2$ and $F_3$ populations, showing that genetic equilibrium was reached in $F_2$, as may be expected in view of the Hardy-Weinberg law on panmixis. 5. As in past trials, Hawaiian Flinty Dent, a variety, yielded as high as Philippine Hybrid No. 1.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.389-398
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• 2010

The objective of this study was to investigate the effects of three strains of Bacillus subtilis (B. subtilis) supplemented to diets on egg production, egg quality, egg yolk cholesterol levels, the profile of cecal microflora, and tibia characteristics in laying hens. One hundred sixty 76-week-old Hy-Line Brown layers were randomly divided into 4 groups with 4 replicates per group (10 birds per replicate). Birds in the control group were fed a corn-soybean meal based diet. The remaining three treated groups were fed the control diet containing either 0.05% B. subtilis Ch3 (T1), 0.05% B. subtilis Ch3 + B. subtilis W1 (T2) or 0.05% B. subtilis commercial product (T3) for 6 weeks, respectively. There were no differences in feed intake, egg weight, egg production and egg mass among the groups. The dietary supplementation of B. subtilis improved eggshell strength and Haugh units compared to those of control (P<0.05). The activities of GOT and GPT in serum were not also affected by the dietary treatments. The population of total microbes and lactic acid bacteria in cecum were significantly increased by the dietary B. subtilis (P<0.05), but not the coliforms. The cholesterol concentration in egg yolk and serum in the treated groups were significantly decreased compared to those of control (P<0.05). Also, The levels of phospholipids in serum were significantly decreased compared to those of control (P<0.05). The supplementation of three strains of B. subtilis to diets significantly increased the contents of tibia ash compared to that of control (P<0.05). Thus, this study showed significant improvements in egg quality, such as eggshell strength and Haugh unit, by dietary B. subtilis strains. The B. subtilis strains added to the diets modulated the profiles of cecal microflora, reflecting beneficial effects in laying hens.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.94-99
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• 2013

Yanganok, a new single cross variety, was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2012. This hybrid, which has a high yield of grain was produced by crossing two inbred lines, KS164 and KS163. KS164 is the seed parent and KS163 is the pollen parent of Yanganok. It is a yellow-orange intermediate maize hybrid (Zea mays L.). After a preliminary yield trial and advanced yield trial of Yanganok (Suwon180) in Suwon for 2 years, a regional yield trial was carried out for its growth characteristics, and yields were determined at 4 different locations from 2009 to 2012, with the exception of 2010. It was named 'Yanganok'. The silking date of Yanganok is 2 days earlier than that of the check hybrid, Kwangpyeongok. Plant height of Yanganok is similar to Kwangpyeongok, but its ear height ratio is higher than that of Kwangpyeongok. It has resistance to lodging. Stay-green features of Yanganok are similar to those of Kwangpyeongok. The ear ratio of Yanganok is similar to Kwangpyeongok. It has moderate resistance to southern leaf blight (Bipolaris maydis) and strong resistance to northern leaf blight (Exserohilum turcicum). It has moderate resistance to black streaked dwarf virus (BSDV), ear lot and corn borer. The dry matter yield of Yanganok, 17.45 ton/ha, was similar to that of Kwangpyeongok. The total digestible nutrients (TDN) yield of Yanganok, 11.96 ton/ha, was similar to that of Kwangpyeongok. The grain yield of Yanganok, 8.32 ton/ha was similar to that of Jangdaok. Seed production of Yanganok went well due to a good match during crossing between the seed parent, KS164, and the pollen parent, KS163, in Yeongwol, and F1 seed yield was 1.79 ton/ha. Yanganok would be a suitable cultivar to all plain areas in the Korean peninsula.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.6.2-6
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• 1979

Foreing bodies of the esophagus and tracheobronchus are likely to occur whenever a child places an inedible object in the mouth and are common in the older age group particularily in edentulous individuals or preexisting disease. Our department had already reported the statistical survey at first in 1954, successively in 1962, 1963 and 1968, respectively according to the age, sex, variety of foreign bodies, location and duration of the lodgement. Now, we have experienced the new 186 cases during the consecutive 5 year period from January 1973 to December 1977 and reported as a 5th report comparing with previous report. The results were as follows. 1. In the incidence of foreign bodies, coins were the most common and pointed metal, disc, bony fragment were followed in order in the esophagus while the peanut and corn were common in the air passage. 2) 79 cases (56.4%) were males and 61 cases (43.6%) were females in the esophagus, which was not a significant difference to note. But in the air passage, males accounted for 33 cases (71.7%) compared to 13 cases (28.3%) of females. 3) In the aspect of age incidence, child 10 years or under accounted for almost all cases in the esophagus as well as in the air passage. 4) In the location of foreign bodies in the esophagus, the first narrowing was the most common, while in the air passage right bronchus had a high incidence but the difference of incidence between right bronchus and left bronchus was not remarkable. 5) The duration of lodgement was 24 hours or less in more than half of the all cases. 6) In the aspect of kind of coin, 10 won coins accounted for majority of the cases (67.0%) but the incidence of 100 won coins were tend to increase gradually in these years.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.21-25
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• 2014

Singwangok, a new single cross variety, was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2012. This hybrid, consisting of a high yield of grain, was produced by crossing two inbred lines, KS172 and KS173. KS172 is the seed parent and KS173 is the pollen parent of Singwangok. It is a yellow-orange intermediate maize hybrid (Zea mays L.). After the preliminary yield trial and advanced yield trial of Singwangok (Suwon185) in Suwon for 2 years, the regional yield trial of that was subsequently carried out for its growth characteristics and yield at 3 different locations from 2010 to 2012. It was named as Singwangok. The silking date of Singwangok is similar to the check hybrid, Jangdaok. The plant height of Singwangok is similar to Jangdaok, but its ear height ratio is lower than that of Jangdaok. Moreover, it has a resistance to lodging. The ear number per 100 plants of Singwangok is more 17 than that of Jangdaok, whereas the ear length of Singwangok is similar to Jangdaok. Further, the weight of 100 seeds of Singwangok is similar to Jangdaok. It has a moderate resistance to southern leaf blight (Bipolaris maydis) and a strong resistance to northern leaf blight (Exserohilum turcicum). Furthermore, it has a moderate resistance to the black streaked dwarf virus (BSDV), ear lot and corn borer. The grain yield of Singwangok, 7.81 ton/ha, was similar to that of Jangdaok. The seed production of Singwangok was well processed due to the good match during crossing between the seed parent, KS172 and the pollen parent, KS173, in Yeongwol; the F1 seed yield was 3.84ton/ha. Singwangok would be a suitable cultivar to all plain areas in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.1
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• pp.9-16
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• 2022

Rice is one of the most important staple foods in Wnju, Jeonbuk, South Korea. However, rice consumption has dramatically decreased as eating habits have diversified owing to rapid economic growth. Recently, floury endosperm rice varieties have been developed to invigorate the rice processing industry, because dry-milled rice flour is economically and environmentally suitable for massive rice flour distribution. The National Institute of Crop Science has developed 'AromaT', an early-maturing black rice with floury-endosperm, suitable for tea and dry milling. 'AromaT' was derived from a cross between 'Suweon542' as the floury endosperm source and 'Heugjinju' as the black and aromatic source. In this study, 'AromaT' and its parents, 'Suweon542' and 'Heugjinju', were analyzed for agronomic traits, anthocyanin content, and their major physicochemical properties by different planting date. The field experiment was conducted in Wanju, Jeollabuk-do Province, South Korea, in 2019. The transplanting dates were May 30 (ordinary season), June 25 (double-cropping season), and July 10 (late season). The yield performance of brown rice 'AromaT' was 330 kg/10 a in the double-cropping cultivation method and was the highest among the transplanting dates. The floury endosperm of 'AromaT' was derived from 'Suweon542' containing 'flo7', located on chromosome 5 and known to control floury endosperm. With the late planting date, the anthocyanin content of 'AromaT' was 570.5 mg/100 g, much higher than that of 'Heugjinju' (376.3 mg/100 mg). The brown rice of 'AromaT' also exhibited the pop-corn-flavoring 2-acetyl-1-pyrroline, exclusively detected in aroma rice varieties. The average particle sizes of 'AromaT' and 'Suweon542' were 67.12 ㎛ and 70.9 ㎛, respectively, lower than that of 'Heugjinju' (95.5 ㎛) with a black transparent endosperm. The average damaged starch content of 'AromaT' was 8.1%, lower than that of 'Heugjinju' (10.05%) and Suweon542 (9.5%). As a result, 'AromaT' with high anthocyanin content, fine particle size, and low damaged starch content is expected to provide a new rice material in various processing fields.