Background : This study was carried out to introduce Atractylodes macrocephala as a new income element in Gangwon area and to develop the technology necessary for stable quality seedling production. Methods and Results : For the production of high quality seedlings of Atractylodes macrocephala, seedling growth characteristics were investigated according to the types of plug cell size and seedling raising period. Atractylodes macrocephala seeds were sown on February 14, 2018 in 72, 105, 128, 162, and 200 plug trays. The emergence period after sowing was March 2, and the final occurrence rate was 76.6 - 79.5%. The number of days of emergence took 18 to 20 days from sowing date. Growth of seedlings tended to be better with less number of plug trays, such as seedling height, seedling width, leaf length, leaf width and leaf number. On the other hand, roots (net formation) increased rapidly as the number of plug trays increased. After 60 days, the matured seedling rate was good at 75.5 ± 8.4% for the 200 plug tray and 72.5 ± 4.1% for the 162 plug tray. The net formation ratio of matured seedling was the best in 60 days of seeding in 162 plug trays. The rooting rate was 98.0 ± 2.1 - 99.3 ± 1.2% when seeded for 60 days or more regardless of the type of plug tray. Conclusion : In order to produce efficient and stable seedlings in the cultivation of Atractylodes macrocephala in Gangwon area, it was considered to be advantageous for 60 days of seedling settling in the plug trays of more than 162 and less than 200.

Investigation of the plant growth affected by plug cell volume/pot size and plant age in herbaceous native plants belonging to 11 family and 24 species showed that growth of aerial part was different according to both plant age and plug cell volume/pot size. Among them, especially Iris dichotoma, Iris ensata var. spontanea, Iris pseudoacorus Lysimachia vulgaris var. davurica, Campanula glomerata var. dahurica and Solidago virgaurea subsp. asiatica showed more prominent difference depending on plug cell volume compared to other species. Regarding growth of subterranean part, as decrease plug cell volume/pot size root quality index became high while root weight became low, indicating that growth restriction was happened by exceed increase of root density due to limited root zone area. As increase cell volume/pot size, root development became active in bigger than 150 ㎖ of cell volume. Plant quality got better as increase cell volume/pot size, and 60 days old plants (DOP) revealed higher quality than 90 DOP revealed, indicating that marketing is possible from 60 DOP. Considering both plant age and cell volume (pot size), plant quality was better in smaller cell volume when cultivate plants in short time, while better in bigger cell volume when cultivate plants long time. Accordingly, when extend cultivation periods in small volume of plug cell, plant quality became bad. Therefore, this study showed that in order to produce high quality of plants, plants should be grown in proper plug cell volume depending on cultivation periods. Among plants tested Hosta longipes, Aquilegia buergeriana var. oxysepala, Aquilegia japonica, Veronica linariifolia, Hemerocallis fulva, Iris ensata var. spontanea, Iris pseudoacorus, Allium senescens, Hypericum ascyron, Caltha palustris var. palustris, Gentiana scabra, Campanula glomerata var. dahurica, Dendranthema boreale, Dendranthema zawadskii var. latilobum, Aster spathulifolius, Aster maackii, Aster koraiensis and Solidago virgaurea subsp. asiatica were determined to be able to produce standard size nursery plants using plug tray, and proper plug cell volume was bigger than 150 ㎖ (32 cell tray).

The influence of triploidization on cell and nucleus size characteristics of the same tissues of erythrocyte, retina, kidney, hepatocyte and midgut epithelium in marine medaka, Oryzias dancena has been determined histologically. Induced triploid fish are produced by cold shock treatments. Likewise, the size of horizontal cell nucleus in inner nuclear layer of retina, ganglion cell nucleus in ganglion cell layer of retina, proximal tubule cell of kidney, hepatocytes and nuclear height of midgut epithelium all appear to be significantly larger than diploid (P<0.05). On the other hand, retina thickness is larger in diploid than induced triploid (P<0.05). Induced triploid shows low density of cell number. Results of this study suggest that same characteristics in the induced triploid exhibiting larger cells and nucleus sizes with fewer number of cells than the diploid can be useful criteria for the distinction between diploid and induced triploid, and also the ploidy level in marine medaka.

Organ size control is a fundamental developmental processes for higher plants as well as a promising target trait for molecular breeding in crop plants. Genetic mechanisms how plant organs grow to a certain size remains still unclear. Here we present the identification and characterization of a genetic mutant, big flower1-1 (bif1-1) in Arabidopsis that exhibits bigger organ size primarily due to increased cell size. Genetic analysis indicated that it is a single, semi-dominant mutation. Phenotypic analysis showed that bif1-1 exerts pleiotropic effects: it caused bigger seed size, bigger seedling, bigger leaf, thicker stem, increased trichome branching, smaller fruit, and bigger pollen. Microscopic analysis suggested that the bigger organ size in bif1-1 mutant is primarily attributed to increased cell size. Gene expression analysis indicated that most of growth-control genes tested were not altered in bif1-1 mutant. Instead, expression of ARGOS and auxin-inducibility of ANT were reduced in bif1-1 mutant. Our ongoing positional on the corresponding gene would not only shed light on the molecular mechanisms how plants adopt final organ size but also provide a promising genetic resource for genetic engineering of flower- and seed-size in crop plants.

단옥수수로부터 찰옥수수로 변한 소비자들의 기호성과 홍수출하를 피하고 생산자의 소득을 높이기 위한 주년공급에 대응하기 위해서 조생종과 만생종 찰옥수수의 육묘와 이식재배에 관한 체계적인 연구가 필요한 현실이다. 본 연구는 2007년에 국립식량과학원 시험포장에서 찰옥수수의 조생종 품종 찰옥 1호와 만생종 품종 찰옥 4호를 재료로 하여 풋옥수수의 안정성 높은 이식재배법에 대한 일련의 실험을 수행한 것으로 그 결과를 요약하면 다음과 같다. 1. 육묘기간이 길어질수록 파종 후의 출사일수가 길어지는 반면, 이식후의 출사일수는 짧았는데, 출사일수는 찰옥 1호가 찰옥 4호에 비하여 9~12일, 그리고 2기작이 1기작에 비하여 12~15일 정도 짧았다. 2. 육묘 이식재배한 찰옥수수의 간장은 육묘일수가 길수록 감소하는 경향이었으며, 직파재배에서 간장은 2기작재배에서 1기작재배에 비하여 찰옥 1호는 17%, 그리고 찰옥 4호는 24% 감소하였다. 3. 이삭길이는 육묘일수가 길어질수록 다소 감소하였는데, 찰옥 1호는 1기작재배에 비하여 2기작재배에서 크게 감소하였다. 4. 상품 이삭수는 직파재배에서 2기작재배가 1기작재배에 비하여 찰옥 1호는 64% 감수하였고, 찰옥 4호는 12%로 감소하여 그 정도가 적었다. 5. 상품 이삭수로 보아 찰옥수수의 적정육묘일수는 찰옥1호는 1기작재배 15일 육묘, 2기작재배는 이식재배 보다 직파재배가 적당하고, 찰옥4호는 모든 작기에서 20일 육묘로 판단되었다.

본 연구는 2007년 국립식량과학원 시험포장에서 찰옥수수의 조생종 품종 찰옥 1호와 만생종 품종 찰옥 4호를 재료로 하여, 적정육묘 일수, 충실한 묘를 육성하기 위한 플러그셀 크기에 대한 일련의 실험을 수행한 것으로 그 결과를 요약하면 다음과 같았다. 1. 찰옥수수 묘의 묘장, 엽수 및 건물중은 파종기와 플러그셀 크기에 따라서 고도로 유의한 차이가 있었으나, 품종간에는 차이가 없었는데. 찰옥수수의 묘는 3월 파종 보다 5월과 7월 파종에서 생장속도가 빨랐다. 2. 찰옥수수 묘의 묘장과 엽수는 육묘일수가 길수록 증가하였는데, 3월 14일 파종에서는 30일 묘(21.6 cm), 5월 8일 파종에서는 15일 묘(25.5~26.9 cm), 그리고 7월 3일 파종에서는 10일 묘(21.6~24.0 cm)에서 이식에 적합한 묘장이 되었으며, 엽수는 3월 14일 파종에서는 파종 후 15~20일, 그리고 5월 8일과 7월 3일 파종에서는 파종 후 10일에 이식에 적합한 2~3매가 되었다. 3. 건물중도 육묘일수가 길어질수록 증가하였는데, 3월 14일 파종에서는 육묘 30일에 0.43g, 5월 8일 파종은 20일에 0.57~0.67g, 7월 3일 파종은 15일에 0.53g이었고, 또한 육묘일수가 길어질수록 건물중 증가속도가 2~3배 빨라졌다. 4. 묘장과 엽수로 보아 찰옥수수의 적정육묘일수는 모든 플러그셀 크기에서 3월14일 파종에서는 20일, 그리고 5월과 7월 파종에서는 10~15일이었다. 5. 찰옥수수 플러그묘의 묘장, 엽수, 엽면적 및 건물중 간에는 높은 정의 상관이 있었으나, 엽색도는 대부분의 형질과 부의 상관을 보였다.

The experiment was conducted to improve the selection efficiency m the first generation through the analysis of variation pattems of major tuber characteristics when raising hybrid seedling using the different plug cell size. The correlations in related t