• Journal of the Korean earth science society
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• v.42 no.3
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• pp.247-263
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• 2021

Climate change has been accelerating in coastal waters recently; therefore, the importance of coastal environmental monitoring is also increasing. Chlorophyll-a concentration, an important marine variable, in the surface layer of the global ocean has been retrieved for decades through various ocean color satellites and utilized in various research fields. However, the commonly used chlorophyll-a concentration algorithm is only suitable for application in clear water and cannot be applied to turbid waters because significant errors are caused by differences in their distinct components and optical properties. In addition, designing a standard algorithm for coastal waters is difficult because of differences in various optical characteristics depending on the coastal area. To overcome this problem, various algorithms have been developed and used considering the components and the variations in the optical properties of coastal waters with high turbidity. Chlorophyll-a concentration retrieval algorithms can be categorized into empirical algorithms, semi-analytic algorithms, and machine learning algorithms. These algorithms mainly use the blue-green band ratio based on the reflective spectrum of sea water as the basic form. In constrast, algorithms developed for turbid water utilizes the green-red band ratio, the red-near-infrared band ratio, and the inherent optical properties to compensate for the effect of dissolved organisms and suspended sediments in coastal area. Reliable retrieval of satellite chlorophyll-a concentration from turbid waters is essential for monitoring the coastal environment and understanding changes in the marine ecosystem. Therefore, this study summarizes the pre-existing algorithms that have been utilized for monitoring turbid Case 2 water and presents the problems associated with the mornitoring and study of seas around the Korean Peninsula. We also summarize the prospective for future ocean color satellites, which can yield more accurate and diverse results regarding the ecological environment with the development of multi-spectral and hyperspectral sensors.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.611-615
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• 2011

'Manjong' is a new japonica rice cultivar developed in 2009 derived from a cross between 'Yeongdeog34' and 'Nampyeongbyeo' at the Department of Functional Crop, NICS, RDA. This cultivar is suitable for the double cropping system after the cash crop cultivation. Heading date of 'Manjong' is later than 'Keumobyeo' under the late transplanting cultivation on July 10. It has high grain fertility under cold conditions and low premature heading. One of the distinguishing characteristics of this variety is its resistance to major diseases like leaf blast and rice stripe virus disease. However, it shows susceptibility to major insect pests and bacterial blight disease. Milled rice kernels are translucent with non-glutinous endosperm and have 7.2% protein and 18.7% amylose contents. Ripening ratio and head rice ratio is very higher than those of 'Keumobyeo'. The palatability of cooked rice is also better than 'Keumobyeo'. The milled rice yield of 'Manjong' in local adaptability tests after harvest of the cash crop is $4.81MT\;ha^{-1}$. This cultivar is suitable for planting in the plain paddy fields of Honam and Yeonnam regions in Korea.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.649-653
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• 2010

'Dacheong', a new japonica rice variety developed from a cross between Iksan450 having a good eating-quality and multi-disease resistance, and YR21258-GH3 having insect resistance, was developed by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2008. This variety has about 125 days growth duration from transplanting to harvesting in west-southern coast, Honam and Youngnam plain of Korea. It has 87 cm culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen races from $K_1\;to\;K_3$, stripe virus and brown plant hopper. The milled rice of 'Dacheong' exhibits translucent, relatively clear non-glutinous endosperm and medium short grain. It has slightly lower amylose content of 18.8% and lower protein content of 5.7%, and good palatability of cooked rice compared with Nampyeongbyeo. The milled rice yield performance of this variety is about 5.91 MT/ha in local adaptability test for three years. 'Dacheong' would be adaptable to west-southern coast, Honam and Youngnam plain of Korea.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.615-622
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• 2010

A new rice cultivar, 'Joami', was developed by the rice breeding team of Sangju Substation, National Institute of Crop Science (NICS), Rural Development Administration. It was selected by a bulk and pedigree methods from a cross-combination among 'Sambaegbyeo', 'Yukara', and 'Tonggae112'. A promising line of YR20557-1-1-3-B-3 was designated as 'Sangju 36' in 2006. Local adaptability test of 'Sangju 36' was conducted at ten sites throughout the Korean peninsula during three years from 2006 to 2008. 'Sangju 36', thereafter, was registered as 'Joami' in 2008. The cultivar headed on July 30 in the test of local adaptability. Endosperm of 'Joami' is translucent with clear chalkiness and has 5.4% higher head rice ratio than that of 'Odaebyeo'. The yield potential of 'Joami' in milled rice is about 5.40 MT/ha under ordinary fertilizer level of local adaptability test, which was 6% higher than that of 'Odaebyeo'. In an alpine area of Korea, the rice variety needs a cold tolerance and a resistance to blast disease. 'Joami' showed a tolerance reaction at Chuncheon cold tolerance screening nursery and exhibited resistance reaction to blast disease in nation-wide disease screening nursery. Therefore, 'Joami' would be well adaptable to mid-mountainous area at central and southern part of Korean peninsula.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.313-317
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• 2010

There are the farmer's needs to develop early-maturing cultivar adaptable to mid-northern inland plain and alpine area. Furthermore, it is required to develop a rice variety to produce new rice before concentrated marketing dates, even in the years of early Chuseok. 'Joun' is a new extremely early-maturing japonica rice cultivar developed in 2009 from the cross of SR14880-173-3-3-2-2-2/Unbong20 at Cheolwon Substation, National Institute of Crop Science (NICS), Rural Development Administration (RDA). The heading date of 'Joun' is July 23 in mid-northern alpine area, which is 7 days earlier than that of Odaebyeo. It has about 61 cm in culm length with semi-erect plant type. Panicle has a few awns and its exertion is good. The number of spikelets per panicle is smaller than that of Odaebyeo and 1,000 grain-weight of brown rice is 21.2 g which is less than 26.3 g of Odaebyeo, but the complete grain ratio is higher. Milled kernels are translucent with non-glutinous endosperm and palatability of cooked rice is good. It shows strong resistance to cold treatment, lodging, premature heading, wilting and viviparous germination during ripening stage. This cultivar shows resistance to leaf blast disease but susceptible to bacterial blight, virus disease and insect pests. The milled rice yield performance of 'Joun' is about 5.18 MT/ha by ordinary culture in local adaptability test for three years. This cultivar may be highly adaptable to the mid-northern inland plain and alpine area, north-eastern coastal area and middle plain area.

• Korean Journal of Breeding Science
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• v.42 no.2
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• pp.169-180
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• 2010

This study was conducted to investigate characteristics of panicle traits which are important factors affecting yield and grain quality of rice. Twelve panicle traits in 178 Korean rice varieties composed of 160 Japonica type varieties and 18 Tongil type varieties were investigated. Tongil type varieties had longer panicle and thicker neck node than Japonica type varieties. Other traits such as number of total spikelets, total rachis-branches, secondary rachis-branches (SRBs) per panicle, total spikelets on SRBs per panicle, mean number of spikelets on a SRB, and mean number of SRBs per primary rachis branch (PRB) in Tongil type varieties were also higher than in Japonica type varieties. On the other hand, Japonica type varieties were shown to have well exserted panicle and little more mean number of spikelets on a PRB than Tongil type varieties. According to cluster analysis based on 12 panicle traits, 178 varieties were divided into four main groups. Group I had 133 Japonica type varieties and was characterized by relatively well exserted short panicle, small thickness of neck node, few rachis-branches and little sink size than other group. Group II was composed of 24 Japonica type varieties and 6 Tongil type varieties showing medium value and range between Group I and III. Group III included 11 Tongil type varieties and 1 Japonica type variety 'Baegjinju1' characterized by relatively poor exserted long panicle, big thickness of neck node, many rachis-branches and large sink size. Group IV was solely composed of 'Nongan', which had well exserted long panicle, big thickness of neck node, many rachis-branches and large-sink size. In correlation analysis, number of total spikelets per panicle showed very high correlation with the number of total rachis-branches per panicle (r=0.975), number of spikelets on SRBs per panicle (0.962), number of SRBs per panicle (0.959), mean number of SRBs per PRB (0.746) and mean number of spikelets on SRBs (0.738).

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.543-548
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• 2011

Haiami is a new Japonica rice variety developed from a cross between 'Jinmibyeo' TR treated with ethyl methane sulfonate (EMS) EMS and 5-methytryptophan, and 'Gyehwabyeo' in order to develop a new premium quality rice variety by a rice breeding team of National Institute of Crop Science, Rural Development Administration in 2008. This variety has about 138 days of growth duration from transplanting to harvesting in central plain area of Korea. The heading date of this vareity was on $15^{th}$, August. The 'Haiami' has good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Haiami' is more than that of 'Hwaseongbyeo'. This variety shows slow leaf senescence and considerable tolerance to viviparous germination. It is susceptible to leaf blast, bacterial blight, and insect pests, but resistance to rice stripe virus. The milled rice of this variety exhibited translucent, clear non-glutinous endosperm and short grain shape. The essential amino acid properties of 'Haiami' have more than 31% that of 'Hwaseongbyeo' in polished rice. This variety has premium palatability of cooked rice. The yield performance of this rice cultivar was about 5.38 MT/ha in milled rice in local adaptability test for three years from 2006 to 2008. 'Haiami' is adaptable to central and southern plain areas of Korea.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.533-536
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• 2008

Hopum is a new japonica rice cultivar developed from the cross between Milyang165 and F1 crossing Milyang165 and Iksan438 at Department of Rice and Winter Cereal Crop, NICS, RDA, in 2006. This cultivar has a short grain shape and about 141 days growth duration from direct seeding to harvesting in the southern plain including Chungcheong province. This cultivar has short culm and spikelet number per panicle is similar to that of Nampyeongbyeo, while filled grain rate is lower than standard variety. This cultivar has medium size of brown rice and shows moderate resistance to leaf blast, to bacterial blight pathogens of $K_1$, $K_2$ and $K_3$ and stripe virus disease but susceptible to major virus diseases and insect pests. The milled kernel of Hopum is translucent with non-glutinous endosperm. Protein and amylose content of Hopum is about 6.5% and 18.7%, respectively. This cultivar has better palatability of cooked rice than Chucheongbyeo harvested in Gyeongki province. Its milling recovery (76.8%) and percentage of perfect-shaped milled rice (94.7%) were higher than Nampyeongbyeo. The milled rice yield of Hopum was 5.83 MT/ha (15% higher than Juan) under wet-direct seeding, 5.66 MT/ha (8% higher than Juan) under dry-direct seeding, and 6.00 MT/ha (8% higher than Nampyeong) under ordinary transplanting cultivation. "Hopum" would be adaptable for ordinary transplanting and direct seeding in the southern plain including Chungcheong province.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.1
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• pp.55-62
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• 2019

Rapeseed meal, which is a byproduct of rapeseed oil extraction, improves crop productivity by supplying nutrients to the soil. The present study aimed to manufacture fermented rapeseed meal compost using two effective microbial agents and evaluate their efficiency as fertilizer. To types of fermented rapeseed meal, manufactured using either a bio-carrier or microbial agent, showed no differences in pH, electrical conductivity (EC), and total nitrogen content. However, the contents of $NH_4-N$ and $NO_3-N$ as inorganic nitrogen were increased by 5.6 times and 1.5 times, respectively, after 5 d of fermentation. Rapeseed meal fermented for 5 d was applied to tomato a basal fertilizer and after eight weeks, the plant height increased in all fermented rapeseed treatments compared to that in the chemical fertilizer treatment, and also the quantum yield of photosystem II (PS II) showed the same trend. The total nitrogen content of tomato leaves treated with a microbial fermented rapeseed meal was twice as high as that of that treated with a chemical fertilizer. It was confirmed that the increase in the tomato height was an effect of the rapeseed meal containing inorganic nitrogen, which can easily be absorbed by plants. From these results, it is considered that fermented rapeseed meal manufactured with an effective microbial agent for 5 d showed the highest inorganic nutrient content and greatest growth enhancement in tomato.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.398-409
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• 2018

Organic farming practices including loach based ecosystem-farming have been demonstrated to be effective in conjunction with rice farming to increase yield and quality. This new form of farming combines agriculture and fishery and is quickly developing into a new industry. The current study investigated the effect of rice-fish mixed farming system on the vegetation-diversity function. Vegetation within the four study sites was surveyed and analyzed based on plant taxonomy. The vegetation survey demonstrated that 127 taxa of 38 families, 100 genera, 107 species, and 20 varieties occurred within the study sites. A total of 15 plant species taxa occurred in the rice-fish mixed paddy fields with a fish habitat and did not occur in the conventional paddy field lacking fish habitat. This difference is thought to arise from differences in moisture requirements for vegetation. Life form analysis demonstrated differences in hemicryptophytes, therophytes, and hydrophytes according to fish habitat. The naturalized plants identified were also determined to be species widely distributed throughout Korea. Frequency analysis demonstrated that the rice-fish mixed paddy fields with a fish habitat had a high ratio of both obligate and facultative wetland plants relative to the conventional paddy field. Based on the study results, it is likely that vegetation-diversity will increase with environment diversity. However, no statistical significance was observed according to paddy types. Future research should aim to identify additional environmental factors, including the existence of fish habitat, habitat area, depth of fish habitat, hydrological parameters, water quality, and paddy soil environment, to enhance vegetation-diversity and biocultural diversity.