• KOREAN JOURNAL OF CROP SCIENCE
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• v.12
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• pp.7-14
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• 1972

Four treatment leveles(check 500, 1, 000 2, 000ppm) of Ethrel were applied to barley and wheat grown in greenhouse and fields at three stages (preboot, boot, afterboot) of growth in orderd to induce male sterility and to evaluate possibility of practical $F_1$-hybrid-seed production as gametocide. The results are summarized as follows. 1. The shortening plant height, especially the first internode length. spike length and decreasing 1, 000 seeds weight and induction of male sterility, were observed with all Ethrel theatments. The earier the stage of spraying at the boot and the higher concentration of Ethrel, the greater effects were observed. 2. The most practical level of inducing male sterility occurred ranging from 1, 000-2, 000ppm applied at all stages, while with increasing maturity, greater concentration of Ethrel were required to induce the same level of male sterility. .3. Great differences for male sterility per spike in bagged and unbagged spikes were shown with all treatments indicated ovary receptiveness, and that out-crossing has taken place, 4. Ethrel treatment induced more practicable extent of male sterility in barley than wheat. This results indicated that $F_1$-hybrid-seed production in barley with gametocide appears feasible if high combining ability lines were selected for increased out-crossing ratio. 5. There seemed to be no indication of additive surfactant influence on the Ehrel action in the present studies, and showed an interest on further studies on this matter.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.75-90
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• 2003

A total of 192 Korean landraces were investigated for the comparison of each other as useful germplasm to organic farming and examined correlation between quantitative traits. Almost Korean landraces were classified into medium-heading variety and average days from seeding to heading was 111.1 days. Plant height and culm length were longer about 20∼40cm than general Japonica cultivar. Average width of leaf blade and average length of panicle were 1.3cm and 22.4cm, respectively, Average number of panicles per plant was 10.0 and almost varieties showed low tilling habit. Average length/width ratio of brown rice was 1.7 and several varieties were long grain type and average 1,000 grain weight was 21.6g. In correlation coefficient among quantitative traits, positive significant correlations were observed between culm length and leaf width, days from seeding to heading, but negative correlations were observed between days from seeding to heading and 1000 grain weight. 27.1% of Korean landraces showed weak and lodging degree in culm strength and 3.6% of total varieties showed purple margin on leaf blade and leaf sheath. In leaf blade angle and flag leaf angle, erect type was 46.9% and 10.9%, respectively. 24.0% of total varieties showed the slow and late degree of leaf senescence. The rate of awned type, waxy type and brown seed coat were 74.5%, 20.3% and 4.2%, respectively. The color of stigma, spikelet, apiculus and awn showed diverse color such as white, brown, red and purple.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.1
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• pp.59-65
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• 2014

As for Ethephon treatment, the heading stage is 2 days later at the concentration of 250 ppm and 500 ppm for the booting stage that when there is no treatment, 4 days later at the concentration of 1000 or more ppm but no difference for the blossoming and ripening stage. The culm length get shorter as the concentration of Ethephon is higher and the rate of culm length damaged is 37% for 1500 ppm of booting stage, which is the most effective processing, and the inferior culm length damage rate is bigger than the superior culm length damage rate. There is no difference between the number of glumous flower, culm and litter weight and the non-processing and as for the thousand grain weight, it is slightly bigger than when there is not any processing. The rate of germination is indifferent, the number of seeds get numerous regardless of the concentration of treatment and the number augments by 5% maximum for the booting stage. The number of days it takes from treatment of desiccant to the moisture content for harvesting time is respectively 15 days for seeds of 30 day-treatment, 10 days for seeds of 35 days-treatment and 5 days for seeds of 40 to 45 day-treatment. As for the harvest time after treatment of desiccant, the treatment at $30^{th}$ days and $35^{th}$ after the earing is 8 days earlier than the culture by conventional methods, 8 days earlier for the treatment at $40^{th}$ day. When the desiccant treatment is implemented, the thousand grain weight is heavier as the number of days of treatment gets later. The rate of germination gets higher as the number of days of treatment after earing gets later but there is no statistically significant difference 35 days after the earing. Yields are 37% compared to the culture by conventional methods for the treatment of 30 days after the earing, 70% compared to the culture by conventional methods for the treatment of 35 days after the earing, and 92% compared to the culture by conventional methods for the treatment of 40 days after the earing. The treatment before the physiological maturity impacts greatly upon the quality of seeds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.124-130
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• 2016

In this study, agronomic characteristics and fatty acid composition of 121 flax (Linum usitatissimum L.) germplasms were analyzed. The flax germplasms had a fairly short growth period of 75-95 days. The plant height at maturity varied from 52 to 124 cm. The flower color varied from white to lilac and even purple. Early flowering flax germplasms had white flowers and were resistant to lodging. In early flowering flax germplasms, all agronomic characteristics, including growth period, plant height, branch number per plant, stem diameter, number of capsules per raceme, seed number per capsule, 1000-seed weight, and seed yield, were decreased. The average fatty acid composition of 121 flax germplasms comprised palmitic acid (5.3%), stearic acid (4.3%), oleic acid (29.7%), linoleic acid (13.1%) and linolenic acid (46.4%). The total content of unsaturated fatty acids ranged from 84~94% with an average of 88%. Among the fatty acids, linolenic acid (omega-3) content was the highest with a range of 36~54%. In five selected flax germplasms (Hollandia 1803, Red son, C & F Res Br 1767, Wiera, and Ireland 1657) with high linolenic acid (${\geq}51%$), total lipid and protein contents were 30~36% and 5.4~6.9%, respectively. Overall, flax can practically be adoptable into cropping systems in South Korea and utilized as a scenery crop, since flax has a short cultivation period with diverse flower colors.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.96-96
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• 2017

Rice is a staple food for nearly half of the world's population, with more than 10,000 rice varieties providing almost one-quarter of the global per capita dietary energy supply. Grain size, panicle size and branch number, grain number in a panicle are directly associated with rice productivity. Recently several genes which increase grain yield were identified through map-based cloning. Gn1a, Cytokinin oxidase, is a major grain number QTL and regulates grain number per panicle. Dep1 increases panicle branching and reduced rachis length. SCM2 (APO1) was identified by a QTL for culm strength and increased spikelet number. OsSPL16 (GW8) controls grain size and shape and then increases 1000-weight of seed. In here, to identify genotype of genes related to yield in 400 of rice germplasms possessed in National Institute of Crop Science, we had first chosen 4 of well-known genes related to yield; Gn1a, Dep1, SCM2, and OsSPL16. Among these germplasms, 195, 382, 165, and 353 of germplasms harbored the dominant type of Gn1a, Dep1, SCM2, and OsSPL16, respectively. We grouped these germplasms into a total of 10 groups using genotypes of Gn1a, Dep1, SCM2 and OsSPL16. Most rice germplasms belong to group 1, harbored Gn1a, dep1, gw8 and APO1, and group 10, harbored gn1a, Dep1, GW8 and apo1. Hanareum2 is the highest productive cultivar in Korea but do not have dominant type OsSPL16, so belong to group 1. On the other hand, in the case of Unkwang, belongs to group 10, which has dominant type of OsSPL16 but do not have the remaining genes. We can grasp the differences in rice germplasms through the Profiling of genes related to these grain yield, which will be useful for cross-breeding to integrate grain yield genes. We are continuously observing the genotype and phenotype of rice that possesses grain yield genes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.4
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• pp.329-334
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• 1992

In order to obtain basic informations on establishment of culture system for Cassia tora L. in the southern part of Korea, under vinyl mulching and non mulching conditions, the characters of growth and yield following the difference of fertilization quantity were investigated. All characters, stem length, stem diameter, number of branches, number of pods per plant, pod length, and number of grains per pod, etc., were excellent under the vinyl mulching condition, and of these growth characters, stem diameter, number of pods per plant, and number of grains per pod, etc. were most excellent in the district of N-P$_2$O$_{5}$-K$_2$O=8-6-6Kg /10a. Weight of 1000 grains and seed yield were also high under the vinyl mulching condition, and starting form the district of fertilization quantity N- P$_2$O$_{5}$-K$_2$O=8-6-6Kg /10a, the districts of increasing or decreasing fertilizer tended to be less yield. Also under the vinyl mulching and non mulching, the dispersive analyses of useful characters following the difference of fertilization quantity, were acknowledged to be worth of attention.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.431-435
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• 1992

This experiment was carried out to evaluate Korean red rices as useful genetic resource. Semi-wild red rices were collected from farmer's field of the Korean peninsula from 1988 to 1991. The collected red rices were classified into two groups according to length /width ratio of paddy rice and ecological characters. One was long grain red rice and the other was short grain red rice. Those were evaluated in yield components, culm length and panicle length. Mean number of panicles per hill of collected long grain red rices was 21.5 and that of short grain was 11.8. Number of spikelets per panicile of the long and short grain red rices were 86.1 and 108.7, respectively. 1000 grains weight of long grain was 20.1g and that of short grain was 20.2g. Spikelet fertility of long and short grain were 80.4% and 79.4%, respectively. Culm length of long grain was 103.6cm and that of short grain was 94.8cm. Panicle length of long and short grain were 22.1cm and 21.3cm, respectively. Number of panicles per hill, number of spikelets per panicle and culm length were significantly different between the two groups, however no differences, in panicle, length and seed fertility were found between the two groups.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.28-60
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• 1983

This study was carried out to define the effects of external factors including temperature, moisture, oxygen and light quality on the germination of sesame seeds and to investigate the change of major chemical constituents of seeds during germination. The results obtained are summarized as follows: 1. The average germination ratio was from 95.8% to 97.2% when it was tested every $5^{\circ}C$ intervals from $20^{\circ}C$ to $35^{\circ}C$ and no significant difference in germination ratio was found within $20^{\circ}C$ to $35^{\circ}C$. But the germination ratio dropped rapidly to 32.2% when seeds were germinated at $15^{\circ}C$ and the coefficient of variation become greater(77%) 2. The days required for germination ranged from 1.16 to 1. 64 at the temperatures of $35^{\circ}C$ to $25^{\circ}C$ and they were 3.07 and 10.4 at the temperatures of $20^{\circ}C$ and $15^{\circ}C$, respectively. 3. Considering the germination ratio and days needed, $15^{\circ}C$ was assumed to be the minimum temperature for germination practically and this temperature is recommended for testing low temperature tolerance of seed germination of sesame cultivars. 4. The varieties shown the highest low temperature tolerance were Shirogoma and Turkey. The next varieties shown some degree of low temperature germination were Suweon #29, Naebok and IS 58. The varieties with 70 to 80% of germination ratio were Maepo, Suweon #14, Kimpo, Moondeok, and Haenam. Among the 90 varieties tested, the varieties with comparatively high degree of low temperature tolerance were about 10%, and 70% of the low temperature tolerant varieties were domestic varieties. 5. At $12^{\circ}C$ the Shirogoma was the only variety which showed over 50% of germination ratio, 71.4% of the varieties showed less than 20% of germination ratio. When the temperature was raised to $27^{\circ}C$ 18 days after placement at $12^{\circ}C$ all the varieties showed over 90% of germination ratio within 2days. 6. The amounts of water imbibition needed for seed germination were 0.48 to 0.62 times of the seed dry weight at $25^{\circ}C$ and were significantly different among sesame cultivars. About 63% of water required for germination was imbibed in 2 hours after placement of seeds under the germination condition. 7. Under saturated moisture condition the average germination ratio was 0.42%. In the soil of which water potential was -0.4bar 64.8% of the seeds germinated and the most adequate soil water potential for sesame seed germination was about -0.4 to -5.5 bar. The germination ratio decreased as the soil water potential declined below -5.5 bar. 8. Six out of 10 varieties were not influenced by 5% of oxygen in air germination chamber, while varieties such as Yecheon, PI 158073, IS 103 and Euisangcheon showed 64 to 91% of germination under the 5% oxygen content. Under anaerobic condition, cotyledones were not emerged but only hypocotyl was emerged and elongated. The germination ratio of IS 103 decreased significantly under anaerobic condition. 9. When the seeds were dried for 24 hours after 12 hours imbibition of water, the seeds of Cheongsong did not lose their germination ability and 27.5% was germinated but Suweon #9 and Early Russian failed to germinate. However, the germination ratio of IS 103 decreased when the seed were dried 24 hours after 4 hours imbibition of water and the germination ability of IS 103 was maintained even though the seeds were dried for 24 hours after 24 hours imbibition of water. 10. During germination, sugar content of sesame seed increased rapidly and activity of ${\alpha}$-amylase increased gradually while starch content decreased significantly. The rates of increase in sugar content and enzyme activity and decrease in starch content were significantly lower at $15^{\circ}C$ compared with those at $25^{\circ}C$. 11. During germination of sesame seeds, lipid content in the seeds dropped rapidly and the activity of alkaline lipase increased significantly at early stage of germination. The rate of decrease in lipid content and increase in emzyme activity was lower at $15^{\circ}C$ than at $25^{\circ}C$. 12. Four out of 6 varieties were not affected in germination by light wave length. But Suweon #8 was inhibited in germination by 600-650nm. and IS 103 by 600 to 650nm and 500 to 550nm of light wave length. Suweon #8 showed high germination ratio under 650 to 760 nm and 500 to 560nm, and IS 103 under 400 to 470nm and complete darkness. 13. The germination ratios increased significantly in the seeds of which 1000 grain weight is heavier. When the seeds were placed at soil 4cm deep, Cheongsong and Early Russian failed to emerge their cotyledones, but Suweon #9 and IS 103 showed 32.5 and 50% cotyledone emergence, respectively. The extracts from sesame plant and soil where the sesame was cultivated previously did not affect in the-germination of sesame seeds. 14. The covering by black or transparent polyethylene films increased germination ratio compared with uncovered seeds. The covering was effective in shortening the days needed for germination and in improving the early seedling growth, number of capsules per plant and grain yield. Difference was not so seizable between the two polyethylene films but the transparent film appeared somewhat more effective than the black one. 15. Simcheon, Cheongsong. Suweon #9. PI 158073 and IS 103 showed lower rate of water absorbtion by seed during germination and Suweon #8, Suweon #26, Orotall and Euisangcheon showed high increase in seed weight after water absorbtion by seed.

• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.24-27
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• 1993

This study was conducted to select thin-shelled and high-yielding lines in job's-tears. Two breeding lines of Suwon 3 and Suwon 6 were selected from the local collections. These two lines were tested and investigated on their characteristics under the field condition. The heading date of Suwon 3 and Suwon 6 was later one or two days, but the maturity date was one or two days earlier than that of check variety Kim-jejong, respectively. The number of grains per hill of Suwon 3, Suwon 6 was 50%, 49% greater and the milling rate was 3.8%, 5.6% higher than that of check variety, respectively. Althought 1000 grain weight of Suwon 3 and Suwon 6 was 20g lighter and the rate of ripeness was 6%, 12% lower, the raw grain yield was 22%, 20% higher than that of check variety, respectively. The thickness of seed coat of Suwon 3 and Suwon 6 was thiner and the hardness of seed coat was lower than that of check variety, therefore the milling time was decreased 12%, 7% compare to check variety, respectively. The crude protein contents of Suwon 3 and Suwon 6 was slightly higher and the amino acid composition of Suwon 6 was similar to Kimjejong, but Suwon 3 was lower than that of check variety.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.175-185
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• 2018

The aim of this study was to evaluate the variation of growth and quality characteristics in colored rice from 178 accessions and to develop useful, basic rice breeding data by classifying these germplasm characteristics via principal component (PC) analysis. The coefficient of variation of the 178colored rice accessions were the highest for panicle length (PL) and protein contents, followed by length-width ratio (LWR), 1000-grain weight (TGW), culm length (CL), and amylose contents, whereas the lowest was for the number of panicles per hill (NP), which is a yield component. The results from the PC analysis exhibited eigenvalues and contributions respective to each PC as follows: PC1, 2.06 and 29.49%; PC2, 1.31 and 18.75%; PC3, 1.21 and 17.36%; PC4, 1.01 and 14.38%. The eigenvalues of four PCs were over 1.0, and their cumulative contributions were 79.98%, which completes the necessary condition for evaluation of the 178 colored rice accessions. Cluster analysis showed cluster I as the largest, which included 79 accessions, while clusters II, III, IV, V, VI, and VII comprised 46, 19, 13, 4, 8, and 9 accessions, respectively. Moreover, dark brown accessions were dispersed in clusters I and II, and many resources of purple seed coat color were found in clusters V, VI, and VII. Particularly, cluster V had resources of only black and purple seed coat colors. Resources of cluster VII were found to have a relatively small average CL, PL, and LWR; notably, cluster V had the smallest average TGW, and cluster IV the lowest NP but the highest TGW. Finally, considering the yield potential, growth characteristics, heading stage, and color during breeding of colored rice, we obtained the following conclusions: cluster VII is suitable for breeding of colored rice; cross breeding among clusters I, II, and VII has a high yield potential; and it is possible to produce a superior color by cross breeding plants from cluster V and VI.