• Journal of Ecology and Environment
• /
• 제41권6호
• /
• pp.152-164
• /
• 2017

Background: Natural regeneration of seedlings as well as saplings of Korean fir has been significantly impacted by the browsing from the early stages of their development, potentially, by roe deer for the last two to three decades at the study site since late 1980s. This study was carried out to investigate current status of the disturbance in the seedling development of Korean fir (Abies koreana) on Mt. Hallasan, Jeju Island, Korea. Methods: Field survey was carried out during June and August in 2016 to measure the characteristics of study site and understory vegetation by applying systematic sampling to 125 plots of $5m{\times}5m$ quadrat located on eastern slope of the mountain. Correlation and regression analyses were applied to the variables quantified from the data sets using the SAS software. Results: No saplings with their diameters at breast heights smaller than 5.0 cm were found at the study site indicating the serious disturbance in the natural regeneration of Korean fir at the study site. No seedlings with their heights taller than 36.0 cm were found at the study site indicating even more serious disturbance during earlier stage of the natural regeneration of Korean fir at the study site. A total of 616 individuals of the seedlings of Korean fir were found at 54 out of 125 sampling plots. One hundred thirty-eight seedlings (22.4%) out of 616 individual seedlings have the vestiges for being grazed, potentially, by roe deer. Conclusions: Due considerations should be given to the effects of browsing of the seedlings by roe deer to promote the natural regeneration of Korean fir, ultimately to restore Korean fir. It is needed for the managers of the forest to install fences around the forest area. Exclosure experiments as well as enclosure experiments of different densities of browsing should be carried out. In addition, treatment with different densities of Jeju dwarf bamboo should also be included in the experiment on Mt. Hallasan National Park, Jeju Island, Korea.

• 한국작물학회지
• /
• 제48권3호
• /
• pp.135-138
• /
• 2003

1993-98년 동안 농촌진흥청의 벼직파재배 연구현황과 연구자원 배분의 경제적 합리성에 관한 연구결과는 다음과 같다. 1. 벼직파기술분야별 연구는 과거에는 기초연구부문에 집중되었으나 최근에는 직접 농민들의 현장애로를 타개하기 위한 파종, 입모, 잡초방제, 물관리 등 기능적 문제점을 해결하기 위한 연구투자가 확대되었다. 2. 직파재배의 초기에는 파종과 품종육성 부문에 연구투자가 크게 이루어졌으나 최근에는 그 비중이 줄어들고 시비개선, 잡초 방제, 물관리 부문에 대한 연구자원 배분이 늘어나고 있다. 3. 토양관리와 입모에 관한 연구비중은 줄어들고 있어 농민들의 이 부문에 대한 현장 애로는 크게 감소된 것으로 나타났다. 4. 벼직파재배에 대한 연구의 경제적 성과와 연구자원 배분은 기술분야별 일치성이 커서 합리적인 연구자원 배분이 이루어지고 있다.

• Journal of Plant Biology
• /
• 제38권3호
• /
• pp.281-288
• /
• 1995

The progressive differentiation of interfascicular cambium from residual meristem in the first internode of Ginkgo biloba seedlings was elucidated by light and electron microscopy. The cells of residual meristem were small and homogeneous and heterogeneous in their arrangement but those of the adjacent cortex and pith were large and homogeneous. Some interprocambial residual meristem progressively became elongated and vacuolated during the process of the differentiation. In tangential section, residual meristem composed of long and short cells. The eventual interfascicular cambium had long fusiform initials and short ray initials. Storage materials in the cells progressively disappeared from the interprocambial residual meristem and were absent in early interfascicular cambium. Both the radial and tangential walls of cells of the interprocambial residual meristem were almost the same, but the radial wall became progressively thicker than the tangential wall during differentiation of interfascicular cambium. From these results, it is clear that interfascicular cambium is gradually differentiated from residual meristem.

• 원예과학기술지
• /
• 제30권1호
• /
• pp.90-92
• /
• 2012

흰색에 적색 피크가 가미된 절화용 스프레이 카네이션 품종 'Lepus'는 국립원예특작과학원에서 'Diamond'와 '99258-7' 품종을 교배하여 육성하였다. 'Lepus'는 2000년에 교배하여 2001년부터 2003년까지 생육특성 검정을 하여 품평회를 거쳐 'Wonkyo B2-56'을 선발하였으며 2005년에 종자산업법에 의거 'Lepus'로 출원 등록하였다. 'Lepus'는 화색이 밝고 향기가 대조구보다 강하며, 개화가 빠르고, 절화장이 긴 스프레이 카네이션으로 시들음병에 '중' 정도의 저항성이 있다.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.325-325
• /
• 2017

In the 20th century, the average temperature of Korea has risen by $1.5^{\circ}C$, whereas it has risen by $0.6^{\circ}C$ globally. Few studies have investigated the effect of seeding date in hilly pastures on their growth characteristics and productivity. The purpose of this study was to elucidate the effect of seeding dates at a hilly pasture establishment on its growth characteristics and productivity caused by increasing temperatures in Korea. The experiments were conducted from 2014 to 2016 at Pyeongchang, South Korea, at an altitude 600-700 m above sea level. The composition of grass mixture was tall fescue, orchard grass, perennial ryegrass, Kentucky bluegrass, timothy, and white clover. Treatments comprised four seeding dates (August 13 and 27, and September 10 and 24). The establishment rate was lowest on September 24, resulting in only 20% establishment over the winter, and the proportion of weeds was highest on September 24 (58%). Early seedling growth before overwintering is a critical approach to ensure successful establishment of grassland. The main components were orchard grass and tall fescue on the early seeding date (August 13), and Kentucky bluegrass on the late seeding date (September 24). Late seeding increased the proportion of bare lands invaded by weed species, especially during second and third cutting periods. Early seeding date resulted in a progressive increase in biomass. Total annual production was significantly affected by the seeding date; lowest dry matter production was on September 24 ($2,441kg\;ha^{-1}$), whereas maximum dry matter yield was on August 27 ($6,608kg\;ha^{-1}$). The results of the study indicate that growth condition and productivity could be increased by early seeding, and seeding of grass in the Pyeongchang area should be completed before August 27. However, further studies are needed to determine the ideal seeding date at the hilly pasture establishment in Pyeongchang.

• 한국잡초학회지
• /
• 제12권3호
• /
• pp.292-308
• /
• 1992

Recently agricultural situations are being placed in unfavourable socio-economic environment as followed by rapid decrease of rural population, poor labor quality and high wages of rural society due to high speedy industrialization of social structure in Korea. In addition to those circumstances, under the UR system to be expected in the early future, free trade of agricultural products will be faced inevitably in Korea. Practically prices of rice as a principle food in this country are expensive about three times compared to those of foreign rice markets, and so how to increase the international competitiveness and food supplies are important problems to be solved rapidly. Accordingly an urgent goal is reduction of agricultural production cost by the improvement of labour productivity as a labour saving and cost down cultivation methods as the direct seeding cultivation in rice. But there are many problems in the direct seeded rice cultivation. The important things to be improved in that cultivation are development of rice varieties with lodging tolerance, effective seedling stand, weed control, irrigation management and fertilizing and so on. Moreover agricultural basis as irrigation facilities, land consolidation and farm machineries must be improved for the stability of rice cultivation in the future.

• Molecules and Cells
• /
• 제26권6호
• /
• pp.548-553
• /
• 2008

The erect habit of fruit setting is a unique characteristic of ornamental peppers and wild pepper species. The erect habit is known to be controlled by the up locus on pepper (Capsicum annuum L.) chromosome 12. The result of a genetic analysis using Saengryeog 211 (pendant), Saengryeog 213 (erect), and their $F_1$ and $BC_1$ progeny demonstrated that up is a recessive gene. To develop an up-linked marker, bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP) were employed using 108 $F_{2:3}$ individuals. The closest AFLP marker, $A2C7_{469}$, was located at a genetic distance of 1.7 cM from the up locus and was converted into a cleaved amplified polymorphic sequence (CAPS) marker. This marker was mapped at a genetic distance of 4.3 cM from the up locus. When the CAPS was applied to seven ornamental lines and 27 breeding lines with erect fruit, these genotypes of 28 lines were correctly predicted. Thus, the CAPS marker will be useful for marker-assisted selection (MAS) of pepper breeding lines with the up allele at the early seedling stage.

• 식물병연구
• /
• 제19권2호
• /
• pp.118-120
• /
• 2013

2007년부터 2009년까지 전북 익산지역의 고구마 육묘장에서 봄에 Sclerotium rolfsii에 의한 고구마 흰비단병이 발생하였다. 초기증상은 황화되어 시들고 감염된 조직 주변과 지제부에 흰색의 균사체가 형성되었다. 육묘시기에는 병에 매우 약하여 감염되면 고사된다. 병원균은 배지 위에서 흰색균사가 빠르게 자라고 7일 후 균핵을 형성하였다. 균핵은 처음에 흰색에서 시간이 경과됨에 따라 갈색으로 변하였다. 따라서 고구마에서 발생한 병징, 병원균의 균학적 특징과 병원성을 검정한 결과, 이 병을 S. rolfsii Saccardo에 의한 고구마 흰비단병으로 동정하였다.

• 한국작물학회지
• /
• 제51권4호
• /
• pp.287-294
• /
• 2006

Germination and early elongation of rice after germination were investigated in anoxic air treatment, nitric oxide gas treatment, and six concentrations of mercuric chloride solutions to determine the effects of limited oxygen environment, nitric oxide, and inhibited water flux through cell membrane in $17^{\circ}C$. Anoxic air treatment affected germination of tested six varieties very little. However root elongation rates were severely inhibited while shoot growth was affected less. Reductions in shoot and root elongations demonstrated genotypic variations. Nitric oxide delayed the germination of rice even though it didn't affect the final percent germination. Elongations of root and shoot were inhibited in nitric oxide treatment. The inhibitor effect of nitric oxide on the shoot elongation of rice was less severe, while nitric oxide completely inhibited the root emergence of rice. Concentrations of $HgCl_2$ greater than $300{\mu}M$ dramatically reduced the rate and percentage of germination when compared to distilled water treatment. The reduced percent germination showed the greatest variation among rice varieties in $500{\mu}M$ solution of mercuric chloride. Ansanbyeo, Jinheung, and Odaebyeo were affected less by $HgCl_2$, Nonganbyeo and Sangmibyeo were intermediate, and the germination of Andabyeo was greatly reduced by $HgCl_2$. Root elongation of germinated rice seedlings was more sensitive to oxygen deficits, nitric oxide, and $HgCl_2$ treatments than germination and shoot elongation. In conclusion, poor seedling establishment of rice sown in flooded paddy soils, in which the oxygen supply to the seeds is restricted, appears to the result of limited root elongation rate.

• 생명과학회지
• /
• 제24권10호
• /
• pp.1055-1062
• /
• 2014

본 연구는 떡잎의 발달 동안 지방의 유동 및 대사와 관련된 오이 유전자들의 발현을 조사하여 유전자의 활성을 비교하고자 하였으며, 글라이옥시좀과 미토콘드리아 사이의 탄소원(아세틸 단위)의 가능한 경로를 탐색하고자 하였다. 네 곳의 세포 내 소기관인 글라이옥시좀(퍼옥시좀), 미토콘드리아, 엽록체 및 세포질에서 작동하는 중요 대사경로의 10개 유전자들이 조사되었다. 나아가 암소에서 발아한 유식물체의 발아 초기 반응과 이후 3일간 빛을 주었을 때의 반응을 조사하였다. 역전사-중합효소연쇄반응(RT-PCR)에 따르면, 유식물체의 발달 동안에 저장지방의 유동과 관련된 Thio2, ICL 및 MS 유전자는 항상 유사한 유전자 발현 양상을 나타냈다. 오이의 발아 초기에 BOU 유전자와 함께 ICL 및 MS 유전자의 공조된 발현은 퍼옥시좀과 미톤콘드리아 사이에 아세틸 단위의 2차 통로의 존재 가능성에 대한 강한 증거이다. 앞서 보고된 연구에서 보여준 BOU 활성에서처럼 BOU 유전자는 빛 의존성으로 암소에서는 세포막의 미약한 발달로 인하여 활성이 저하됨을 암시한다. 나머지의 유전자들은 떡잎이 초록색으로 발달하고 노쇠화 할 때까지 떡잎의 전 발달 기간 동안에 활성을 나타냈다. 본 연구에서는 아세틸 단위의 운반에 대한 새로운 추가적 제안으로써 지방 저장 종자의 발아와 오이 떡잎의 발달과 관련된 유전자의 발현을 통해 처음으로 확인하였다.