Happymi is a new sweetpotato variety developed from Mokpo Experiment Station, National Institute of Crop Science(NICS), RDA in 2004, which was for the raw eating and processing. This variety was selected from the cross between Chinmi andMA 3 in 1996, seed

A six-rowed naked barley cultivar, Donghanchal (Hordeum vulgare L.), with low-amylose, winter hardiness, viral disease resistance and good quality, was developed from the cross between the advanced line “Masangwamac/Kangbori*7” and Naehanssalbori in 1993.

Expanded rice husk (ERR) is different from commercial rice seedling media in chemical and physical properties such as pH, permeability, and water content. This study was conducted to test a possibility of improving rice seedling growth by improving the texture of ERR as a rice seedling medium. The seedling media used were a commercial seedling medium (CSM), rice husk, and ERR 1, 2, 3, and 4 with different expansion degrees. The pH of the ERHs ranged from 6.3 to 6.8. As the expansion rate increased, ERR particle sizes decreased, and water permeability and absorption rates improved. No significant differences in shoot dry weight and rate of maturity were found among the seedlings cultivated in the different ERH media. However, the mat formation of seedling roots became loose as the expansion rates were decreased. Further studies are necessary to determine the cause of poor root growth in ERH media.

This study is to identify the physiological traits of submergence-tolerant varieties of rice plants (Oryza sativa L.) in Yeongnam area, southeastern part of Korea, where the reduction of rice yield due to submergence is remarkably severe. In the present study, two tolerant varieties of rice plants were selected from over 30 rice varieties grown in under a 10-day period. The tolerant varieties selected from a submerged paddy field. As a control, one intolerant variety of rice plant was chosen. Of the tolerant variety Samgangbyeo, rather than Haepyungbyeo, had a lower dissolved oxygen consumption and maintained a higher dry weight than the intolerant variety. The leaf photosynthetic rates (LPS) of the two tolerant varieties were significantly higher than that of the intolerant-variety after four days of submergence treatment. These results indicate that lower dissolved oxygen consumption in a limited pool is prevented by ethylene formation in the tolerant varieties, which may be a mechanism of submergence tolerance.

The genetic base was defined as the ancestral pool from which crop varieties were derived, and was used to characterize genetic diversity in crop breeding. Number of primary parents used between 1913 and 2002 in Korean soybean breeding programs was 65 and

A new six-rowed naked barley cultivar, “Saenul”, was developed from a double cross between the F1 of Yonezawamochi/Olbori and Dangomugi at National Honam Agricultural Experiment Station RDA in 2001. It has the traits of early maturity, cold resistance, re