• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.143-151
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• 2010

The impact of climate change on rice plants in Gangwon province was examined by comparing the climatic conditions during the recent 10 years (2000~2009) with those of normal (1971~2000) years, and by evaluating the rice plant responses. The daily mean air temperature increased by $0.5^{\circ}C$ while the daily range decreased by $0.1^{\circ}C$ as compared with the normal years. During the main rice growing period in field (from June to September) precipitation increased from 900 to 1,051mm and sunshine hours decreased from 704 to 619 hours. The respiration consumption effect during the rice growing period increased by 0.07 as a result of increased air temperature and reduced sunshine hours. The optimum heading date (determined by the mean air temperature for 40 days after the heading) was delayed in Chuncheon, Hongcheon, Wonju, and Gangneung compared with the normal. The maximum climatic yield potential based on mean temperature and sunshine hours for 40 days after the rice heading decreased by 94 kg/10a mainly due to the decrease in sunshine. The mean air temperature for 40 days after the rice heading from 1999 to 2009 in Chuncheon, Cheorwon, and Gangneung was generally above $22^{\circ}C$ implying that yield and quality of rice can be reduced. Therefore, it is necessary to delay the heading date by planting mid- to late-maturing varieties or by changing the transplanting date in order to produce high quality rice and to maintain rice productivity. In addition, it is also important to develop or select cultivars suitable to changing climate for each region in Gangwon province.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.423-435
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• 1984

The reproductive cycle of the small filefish, Rudarius ercodes was investigated based on the annual variations of gonadosomatic index(GSI) and hepatosomatic index(HSI) by electronic and photic microscophy. The specimens used were collected at the coastal area of Benden island, Sizuokagen, Japan, from September 1982 to August 1983. GSI began to increase from March, starting season of longer daylength and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between November and February without any evident variation. The annual variations of HSI were not distinct in male filefish and were negatively related to GSI in female : HSI decreased in the summer season when the ovary was getting mature and reached the maximum in the winter season when the ovary was getting retrogressive. The ovary consisted of a pair of saccular structure with numerous ovarian sacs branched toward the median cavity. Oogonia divided and proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophile cytoplasm showed several scattering nucleoli along the nuclear membrane. when the oocytes growing to about 300 ${\mu}m$, nuclear membrane to disappear with nucleus migrating toward the animal pole. The regions of protoplasm were extremely confined within the animal hemisphere in which most of cytoplasms were filled with yolk materials and oil drops. After ovulation, residual follicles and growing oocytes remaining in the ovarian sacs degenerated. But perinucleatic young oocytes without follicles formed were not degenerated, and growing continuously still in the next year. Mitochondria and endoplasmic reticula in the cytoplasm remarkably increased with oocytes maturing and yolk accumulating. Those were considered to be functionally related to the yolk accumulation. Five or six layers of possible vitellogenin, oval-shaped disc structures with high electron density, appeared in the apex of follicular processes stretching to the microvilli pits of mature oocytes. Testis consisting of a pair of lobular structures in the right and left were united in the posterior seminal vesicle, Cortex of testis was composed of several seminiferous tubules, and medulla consisting of many sperm ducts connected with tubules. Steroid hormone-secreting cells with numerous endoplasmic reticula and large mitochondria of well developed cristae were recognized in the interstitial cells of the growing testis. Axial filament of spermatozoon invaginated deeply in the central cavity of the nucleus and the head formed U-shape with acrosome severely lacking, mitochondria formed large globular paranuclei at the posterior head, and microtubular axoneme of the tail represented 9+9+2 type. The annual reproductive cycles could be divided into five successive stages : growth(March to July), maturation(May to September), Spawning(mid May to early October) and resting stages(October to February). The spawning peak occurred from June to August.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.314-318
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• 2009

A new rice cultivar "Jinbaek" carrying Xa3 and xa5 was derived from the cross between 'HR15204-38-3' with xa5 gene resistant to bacterial blight K1, K2, K3 and K3a, and F1 plant derived from the cross between Junam and Sindongjin with Xa3 gene. "Jinbaek" has approximately 125 days of growth duration from transplanting to harvesting in the west-southern coastal and Honam plain of Korea. Culm length of "Jinbaek" is 71 cm. In reaction to biotic stresses, it shows moderate resistance to blast, and wide spectrum resistance to bacterial blight pathogen, K1, K2, K3, and K3a but susceptible to rice stripe virus and blast. The milled rice of "Jinbaek" exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has lower amylose content (18.8%) and protein content (6.2%) compared with Nampyeong. The milled rice yield of this cultivar was 5.30 MT/ha in local adaptability test of three years from 2006 to 2008. This cultivar would be adaptable to the bacterial blight-prone area in the south-western coast and Honam plain of Korea.

• 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.40 no.4
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• pp.503-506
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• 2008

'Saenuri' is a new japonica rice variety developed and registered by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2007. This variety was derived from a cross between Gyehwa17 with lodging tolerance and high yield potential, and HR14026-B-68-6-1-5 with resistance to diseases and good eating quality. This variety has about 124 days growth duration from transplanting to harvesting in west-southern coast, Honam and Youngnam plain of Korea. It is about 78 cm in culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows moderately resistance to blast, and resistance to bacterial blight pathogen races from K1 to $K_3$ and stripe virus, but susceptible to other major diseases and insect pests. The milled rice of "Saenuri" exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has similar amylose content of 19.0% and lower protein content of 6.1%, and good palatability of cooked rice compared with Nampyeongbyeo. The milled rice yield performance of this variety is about 5.71MT/ha in local adaptability test for three years. "Saenuri" would be adaptable to west-southern coast, Honam and Youngnam plain of Korea.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.520-524
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• 2009

A newly developed rice variety "Pungmi 1" is a japonica rice(Oryza sativa L.) with high grain quality and multi-resistant to diseases. It was developed by the rice breeding team of Yeongnam Agricultural Research Institute (YARI), RDA. in 2004. This variety derived from a cross between "YR13616Acp 1", having short culm and multi-resistance to biotic stresses and "Milyang 122" with good grain quality. It has short stature of 73cm in culm length and mid-early flowering date of Aug. 13. This variety is moderately resistant to leaf blast showing durable resistance of lower 10% diseased leaf araea in sequential planting meothod. Milled rice kernel of "Pungmi 1" is translucent, clear in chalkness and good at eating quality in panel test. Milling recovery and head rice ratios were comparable to Milyang 122, while it has low protein content. The milled rice yield potential of "Pungmi 1" is about 5.59 MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to Yeongnam inland plains and southern coastal areas of Yeongnam province at ordinary transplanting as well as after barly cultivation.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.252-256
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• 2010

'Honong' is a new japonica rice variety developed and registered by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2009. This variety was derived from mutagen MNU (N-methyl-N-nitrosourea) treatment on fertilized egg cells of Unbong31. This variety has about 126 days growth duration from transplanting to harvesting in west-southern coast, Honam and Youngnam plain of Korea. It has 79 cm in culm length and is tolerant to lodging. In reaction to biotic and abiotic stresses, it show resistance to blast, bacterial blight pathogen races from $K_1$ to $K_3$ and stripe virus, but susceptible to other major diseases and insect pests. The milled rice of 'Honong' exhibits translucent, relatively clear non-glutinous endosperm and medium short grain. It has higher amylose content (20.3%) and lower protein content (6.3%), and good palatability of cooked rice compared with Nampyeong. The milled rice yield performance of this variety is about 5.44MT/ha in local adaptability test for three years. 'Honong' 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.3
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• pp.257-261
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• 2010

'Manmibyeo', a new japonica rice cultivar, is a mid-late maturing ecotype cultivar developed by the rice breeding team of Department of Functional Crop, NICS, RDA in 2002. This cultivar was originated from the cross between 'Milyang 95' and $F_1$ of the cross between 'Bukrukbanna' and 'Milyang 95' in 1990/1991 winter season. It was selected by pedigree breeding method until F6 generation, and a promising line, YR14545-9-2-3-4, was advanced and designated as 'Milyang 162' in 1996. The local adaptability test of 'Milyang 162' was carried out at seven locations during 3 years in 1997, 1998 and 2002. It has about 86cm culm length and is lodging tolerant. This cultivar is susceptible to bacterial blight ($K_1$, $K_2$, $K_3$) and stripe virus, and moderately resistant to leaf blast disease. Milled rice kernels of 'Manmibyeo' is translucent with low amylose content in endosperm, clear in chalkiness and good at eating quality in panel test. The yield potential of 'Manmibyeo' in milled rice was about 4.46 MT/ha at ordinary fertilizer level in local adaptability test. This cultivar would be adaptable to the southern plain of Korea.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.188-191
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• 2008

'Hwangkeumnuri' is a japonica rice variety developed and registered by the rice breeding team of Honam Agricultural Research Institute, NICS, RDA in 2006. This variety was derived from a cross between 'Milyang 165' (Junambyeo) with good quality and high yield and HR14732-B-67-2-3 with multi-disease resistance. This variety has about 125 days growth duration from transplanting to harvesting in west-southern coast, Honam and Youngnam plain of Korea. It is about 76 cm in culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen from $K_1$ to $K_3$ and stripe virus, but susceptible to other major diseases and insect pests. The milled rice of 'Hwangkeumnuri' exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has similar amylose content of 18.9% and lower protein content of 6.2%, and good palatability of cooked rice compared with 'Nampyeongbyeo'. The milled rice yield performance of this variety is about 5.74 MT/ha in local adaptability test for three years. 'Hwangkeumnuri' would be adaptable to west-southern coast, Honam and Yeongnam plain of Korea.