Influences of different seeding dates on growth, seed yield, fatty acid composition and oil content were investigated in flax plants for two years. The results indicated that plant height in early seeding date was higher than that of delayed seeding dates during first season. Furthermore, seeding date also significantly affected the ripened seed rate and the rate increased with the delay in seeding date in first season. Seed yield in the first crop season was significantly higher than the second crop season. Palmitic acid showed variation in different seeding dates. Contrarily, stearic acid was stable and did not changed by different seeding dates. Linolenic acid was found in highest amount in all seeding dates consecutively in two cropping years. Highest oil content was recovered from the seeds of flax sown at 29 Apr. and May 9 in first and second cropping year respectively.

Cryopreservation has been known as an efficient method for long-term preservation of clonally propagated plants, and several cryopreservation methods have been developed. Among them, a droplet-vitrification method for potato using axillary shoot tips in vitro has been established previously. In this study, we have optimized the procedure in which explants were submitted to a step-wise pre-culture in liquid sucrose-enriched medium (0.3 and 0.7 M for 7 and 17 h, respectively). The pre-cultured explants were dehydrated with PVS3 (w/v, 50% glycerol + 50% sucrose) for 90 min or modified PVS2 vitrification solution (w/v, 37.5% glycerol + 15% DMSO + 15.0% ethylene glycol + 22.5% sucrose) for 30 min. This two dehydration solutions produced post-cryopreservation regeneration percentages of 57.2% and 80.9%, respectively. We also compared a new post-culture medium (0.1 mg L ･ -1 GA3, 0.1 mg L ･ -1 kinetin) with the conventional one (0.15 mg L ･ -1 IAA, 0.2 mg L ･ -1 zeatin, 0.05 mg L ･ -1 GA3); the shooting initiation rates were 80.9% and 43.5%, respectively. The results suggest that the modified droplet-vitrification protocol described in this study is more effective, easier to implement, and more economical than the droplet-vitrification protocols currently used for potato.

A chemical, MNU-induced hulless barley mutant line designated as 'Mutant 98 (M98)' was developed from a Korean hulless waxy barley cultivar, 'Chalssalbori'. The objective of the study was to determine the genetic basis of 'M98' and the possibility of using 'M98' as breeding parent to improve lysine level. Compared to 'Chalssalbori', 'M98' had large embryo and higher lysine content in both the embryo and endosperm. Significantly different lysine content in 'M98' and the other high-lysine barley mutant stocks was observed for two years. However, the genotype by year interaction was not significant. 'M98' was higher than the other high-lysine barley mutant stocks in the percentage of lysine of total amino acid composition (0.75%). The trait of shrunken endosperm of 'M98', which was typical in the high-lysine mutants, was inherited by a single recessive gene. Based on seed morphology and lysine content of F1 seeds, 'M98' had a genetically different gene from the other high-lysine mutants for shrunken endosperm. Segregation of F2 for plump/shrunken endosperm did not fit the expected ratio of Mendelian inheritance except for only one cross combination (GSHO1784 (lys1)/M98). The amino acid analysis of F5 and F6 progenies from the cross between 'M98' and 'Chalssalbori' revealed that the attempt to increase the range of lysine content of plump lines did not go beyond the limit of the average high-lysine barley germplasm.

"원교 가-단과지 1호"는 농촌진흥청 국립원예특작과학원에서 고품질 중생종 "Starkrimson"에 무측지성 "McIntosh Wijick"을 1992년에 교배하여, 2000년부터 2008년까지 그 특성을 조사한 결과, 과실 특성이 뛰어난 계통을 중간모본으로 최종 선발 하였다. 만개기는 "홍로"와 비슷하거나 2일 정도 느리고, 숙기는 "홍로"보다 일주일 정도 느리다. 수세는 중, 수자는 반개 장형이고, 단과지 형성 및 착과량은 "홍로"와 같이 많은 편이

Venturia nashicola에 의한 검은별무늬병 저항성 품종을 육성하기 위하여 저항성 유전자원 탐색을 1997~1999년까지 국립원예특작과학원 포장검정 및 인공 접종을 실시하여 저항 성친으로 서양배 "청마려"을 선발하였다. 농촌진흥청 국립원예특작과학원 과수과에서 고품질 만생종 "만수"에 "청마려"를 1997년에 교배하여 저항성 우량 계통인 중간모본 "원교나-흑성 2호" 을 2008년에 선발하였다. 2008년 만개일은 4월 19일로 "만수" 보다 1

배는 배우체 자가 불화합성을 보이며, 이것은 단일 유전자좌의 복대립 유전자에 의하여 제어된다. '원교 나-자수정 2호'는 농촌진흥청 국립원예특작과학원에서 고품질 조생종 '원황'에 '92-18-79' (오사이십세기 자식계통, S4smS4sm)를 2001년에 교배하여 얻은 계통 중에 자가 결실성이며 품질이 우수하여 중간모본으로 선발되었다. 만개기는 '오사이십세기'보다 1일 정도 빠르고 '원황'과는 유사하다. 수세는 중, 수자는 반개장형이다. 검은별무늬병(V

"Chuyoung" as a new double cropping potato variety was bred in 2005 for table use through a cross between "Dejima" with short tuber dormancy and HRB-31 which is a tetraploid derived from an interspecific cross between "Russet Burbank" and Solanum phureja line. It was evaluated for short dormancy, growth and tuber characteristics every twice a year from 1997 to 2001. Regional yield trials were performed from 2002 to 2004 at three locations, Jeju, Namhae and Gangneung of Korea, respectively. Its tuber shape is oblong with yellow skin and flesh colors. Its dormant periods is 60~70days. It showed less incidence of physiological disorders such as cracking or knobs on tubers, and higher resistance to common scab by Streptomyces scabies compared to "Dejima". It has tall plant height and erect growth type with green-broad leaflets and white large inflorescence. Its average yields are 29.5 and 22.6 ton/ha at 90 days after planting in spring and autumn cropping, respectively. It also showed higher marketable yield due to the lower incidence of common scab and physiological disorders compared to "Dejima".