• 한국유기농업학회지
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• 제22권1호
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• pp.129-145
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• 2014

서양금혼초의 군락 형성에 따른 경쟁적 우세원인을 규명하고 친환경농자재 개발을 위한 기초자료로 제공하고자 생육특성과 Allelopathy 효과를 알아보았다. 서양금혼초의 생육특성은 예초지역과 비예초지역간의 묘조(苗條) 수, 지상부 직경과 화주 수를 비교한 결과 예초지역의 묘조(苗條) 수, 지상부의 직경과 화주수가 비예초지역보다 높은 것으로 조사되었고, 서양금혼초의 수용성 추출액에 대한 레드클로버(Trifolium pratense), 들묵새(Festuca myuros), 도깨비바늘(Bidens bipinnata) 등 실험식물 14종 대해 발아와 생장 실험 결과 일반적으로 수용성 추출액의 농도가 증가함에 따라 검정식물의 발아율, 유식물의 뿌리털, shoot, root의 생장이 억제되었고 검정식물의 종류와 부위에 따라 억제정도에 있어서 차이를 보였다. 또한 서양금혼초의 수용성 추출액에 대한 실험곰팡이의 생장에 있어서는 Pythium속, Phytophthora속은 수용성 추출액의 농도가 높아짐에 따라 성장이 억제되는 경향을 보인 반면, Rhizoctonia속인 경우에는 농도가 높아짐에 따라 생장억제 현상이 뚜렷하지 않았다. 이와 같은 결과를 종합하여 보면 서양금혼초의 예초는 서양금혼초의 Split현상을 유도하여 더 많은 영양번식과 종자번식을 일으켜 군락을 형성하고, 서양금혼초에 함유된 allelochemicals에 의해 타 식물체의 발아와 생장, 미생물의 생장 등에 관여하기 때문에 제주도내 생태계에서 경쟁적 우위를 점하고 있으며, 친환경농자재로서의 활용 가능성이 있는 것으로 판단되었다.

• 한국약용작물학회지
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• 제5권4호
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• pp.266-275
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• 1997

지모는 야생에서 수집하여 순화재배하고 있는 약용작물로서 근경을 주로 이용하고 있으며 주성분은 사포닌으로서 발한, 진통, 이뇨 등의 약리작용이 있는 것으로 알려져 있다. 본 시험은 전국 각지에서 수집한 지모 재래종 20계통의 작물학적 특성조사로 수집 재래종간 유연관계(類緣關係)를 밝혀 지모의 재래종을 분류하고자 하였다. 1. 화경수, 화축장 등과 같은 화경기관에 관련된 특성들의 변이가 엽장, 근경길이 등 지상부 또는 지하부에 관련된 특성들의 변이 보다 높았다. 2. 지상부 생육이 왕성할수록 화경장, 화경수등 생식기관도 잘 발달되었으나 화경의 발달은 엽의 엽록소함량과 부의 상관관계 를 나타내었다. 3. 지하부 특성은 업의 생육특성보다 화경관련 형질과 상호 관련성 이 높았다. 4. 중심 연결법에 의한 군집 분석결과 크게 2 group으로 분류되었는데 A group은 B group에 비하여 엽수, 화경수가 많고 화경장, 화경직경이 길고 굵으며 지상부 건물중이 무거운 등 지상부 생육이 왕성하였다. 5. A group은 잎의 크기, 화축장 및 화경직경에 의하여 다시 2개군으로 분류되었고 B group은 엽수, 화경수, 지상부 건물중 등에 의하여 2개군으로 분류 되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.230-230
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• 2017

About 200 rice varieties for irrigated and rainfed lowland ecosystems were released in the Philippines, which were bred for improving yield under favorable conditions. Root plasticity plays key roles in maintaining crop productivity under abiotic stressed conditions. We hypothesized that some of these varieties possess root plasticity traits in response to water stressed conditions. This study aimed to evaluate the root system development and dry matter production of 14 randomly selected rice varieties (6 irrigated lowland and 9 rainfed varieties) under progressive drought (PDR) and soil moisture fluctuations (SMF) stress conditions. Two experiments were done in rootbox and line source sprinkler systems (LSS). Each of the varieties was subjected to well-watered (WW), PDR and SMF conditions during vegetative stage in rootbox system while the same genotypes were subjected to different intensities of drought stress under LSS. Under rootbox system, PDR and SMF significantly reduced shoot dry matter production in all varieties relative to their WW controls. Among varieties, NSIC Rc238 (irrigated lowland) showed the least reduction in shoot dry weight (SDW) in both PDR (by 11.8%) and SMF (by 26.9%) conditions. Less reductions in SDW of NSICRc238 were partially attributed to the promotion of L-type lateral roots, thus increasing total lateral root length by 24.2% and 30.7% under PDR and SMF, respectively. In LSS, SDW of NSIC Rc238 under mild drought stress (16-21% soil moisture content (SMC) had 31.8% reduction relative to its WW control (${\geq}22%SMC$) and had lower sensitivity drought index. Compared with the IR64 susceptible check and NSIC Rc9 tolerant check, NSIC Rc238 had higher SDW by 90.8% and 38.6%, respectively. Furthermore, no rainfed lowland varieties included in the experiment performed well under different water stress treatments. The results implied that some other irrigated lowland rice varieties may also possess drought dehydration avoidance root plasticity traits under water-stressed growing environments.

• Molecules and Cells
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• 제28권1호
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• pp.57-65
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• 2009

CDC48 is a member of the AAA ATPase superfamily. Yeast CDC48 and its mammalian homolog p97 are implicated in diverse cellular processes, including mitosis, membrane fusion, and ubiquitin-dependent protein degradation. However, the cellular functions of plant CDC48 proteins are largely unknown. In the present study, we performed virus-induced gene silencing (VIGS) screening and found that silencing of a gene encoding a tobacco CDC48 homolog, NgCDC48, resulted in severe abnormalities in leaf and shoot development in tobacco. Furthermore, transgenic tobacco plants (35S:anti-NgCDC48), in which the NgCDC48 gene was suppressed using the antisense RNA method, exhibited severely aberrant development of both vegetative and reproductive organs, resulting in arrested shoot and leaf growth and sterile flowers. Approximately 57-83% of 35S:anti-NgCDC48 plants failed to develop mature organs and died at early stage of development. Scanning electron microscopy showed that both adaxial and abaxial epidermal pavement cells in antisense transgenic leaves were significantly smaller and more numerous than those in wild type leaves. These results indicate that NgCDC48 is critically involved in cell growth and development of tobacco plants. An in vivo targeting experiment revealed that NgCDC48 resides in the endoplasmic reticulum (ER) in tobacco protoplasts. We consider the tantalizing possibility that CDC48-mediated degradation of an as-yet unidentified protein(s) in the ER might be a critical step for cell growth and expansion in tobacco leaves.

• 원예과학기술지
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• 제31권1호
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• pp.38-49
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• 2013

Prohexadione-calcium (Pro-Ca), ethephon and transient water stress were evaluated in a factorial design, as potential inhibitors of early-season shoot growth of high density orchard management of apple (Malus domestica Borkh.) trees. In the experiment, water stress was imposed to one-half of the 7-year-old 'Golden Delicious'/M.9 apple trees in each of 5 blocks, by stopping irrigation for 3 weeks between 35 and 56 days after full bloom (AFB). Within each whole unit, the following Pro-Ca and ethephon treatments were randomly allocated at $2{\times}2$ factorial: a) 0 or 250 $mg{\cdot}L^{-1}$ a.i. Pro-Ca applied at 28 days AFB and b) 0 or 300 $mg{\cdot}L^{-1}$ a.i. ethephon applied twice (35 and 71 days AFB). All trees were hand thinned to king flowers prior to treatments. Vegetative shoot growth was markedly reduced by Pro-Ca, with its effect being obvious within 14 days after application, while ethephon and water stress treatments were less effective. Pro-Ca had no effect on fruit set and yield but slightly increased fruit size. Ethephon substantially reduced the fruit size and yield but had no effect on fruit set. Water stress reduced fruit set, fruit size and yield. With regard to fruit quality, Pro-Ca did not influence fruit shape, flesh firmness and soluble solids contents (SSC) but slightly reduced titratable acidity. Ethephon had no effect on fruit shape but increased firmness, SSC and acidity, while water stress did not influence these fruit quality attributes. Dry weight of dormant spur buds was reduced by both Pro-Ca and water stress, while increased by ethephon. The larger dormant buds led to the larger spur flowers at the tight cluster stage the following spring. Return flowering was promoted only by ethephon, especially on previous season's shoots. There were no significant interactions between Pro-Ca and ethephon or water stress on most variables observed in this study.

• 한국환경농학회지
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• 제38권3호
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• pp.145-153
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• 2019

BACKGROUND: The 'Gamhong' cultivar, middle season apple with big fruit size and high soluble solid content, has been bred in Korea. However, it was hard to cultivate the cultivar in Korea by serious bitter pit. The relationships between shoot growth, fruit size, and bitter pit may be affected by crop load. This study was conducted for 2 years (7~8 years after planting) to investigate vegetative growth, fruit quality, bitter pit incidence, return bloom, and gross income for optimum crop load of 'Gamhong'/M.9 adult apple tree. METHODS AND RESULTS: The crop load was assigned to 4 different object ranges as follow: 45~64, 65~84, 85~104, and 105~124 fruits per tree. The vegetative growth, average fruit weight, percentage of fruits heavier than 375 g, soluble solid content, and return bloom increased significantly at the crop load range of 45~64 fruits. However, the lowest total gross income per tree may have been caused by the highest bitter pit incidence and the lowest yield per tree in any other crop load range. The total gross income and yield per tree increased significantly at the crop load range of 105~124 fruits and return bloom dropped to 40%, and hence it was possible to occur biennial bearing. It was 85~104 fruits that biennial bearing did not occur and total gross income was as high as the crop load range of 105~124 fruits. Also, the yield of high grade fruits per tree, with fruit weight of 400~499 g and none bitter pit on fruit surface, was highest at the crop load range of 85~104 fruits, compared to other crop load range. CONCLUSION: In considering fruit size, bitter pit incidence, return bloom, and gross income, the optimum crop load range of 'Gamhong'/M.9 adult apple tree in high density orchard was 85~104 fruits per tree.

• 생물환경조절학회지
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• 제31권3호
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• pp.188-193
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• 2022

배초향은 잎을 식용으로 이용하는 작물로 영양생장을 유지하여 잎의 품질과 수량을 높이는 것이 중요하다. 작물의 생장이 영양생장에서 생식생장으로 전환될 경우 잎의 발달이 저하되어 상품성이 하락할 수 있다. 따라서 본 연구는 광주기에 따른 배초향 식물의 개화 특성 및 화서 발달을 조사하여 잎 생산을 위한 적정 광주기를 선발하기 위해 수행되었다. 배초향 종자를 2021년 11월 29일에 105구 트레이에 파종하여 본엽이 4매 발생한 배초향 식물체를 2021년 12월 27일에 각각 포트에 정식하였다. 정식 후 명기/암기 시간을 10/14hrs, 12/12hrs, 14/10hrs, 16/8hrs로 조절하여 처리하였다. 정식 19일 후 광주기가 짧았던10/14hrs에서 첫 개화를 확인하였으며, 12/12hrs에서 20일, 그 외 처리에서는 21일 이후 개화하는 것을 확인하였다. 또한, 명주기가 암주기에 비해 짧을수록 화서의 발달이 증가하는 것을 통해 본 식물이 양적 단일식물의 특성을 가짐을 확인하였다. 배초향의 생육은 광주기가 길수록 엽장, 엽수, 지상부의 생체중 및 건물중, 엽면적이 증가하는 것으로 나타났다. 따라서, 명주기를 14시간 이상으로 처리하는 것이 배초향의 엽채류로서의 생산성을 높이는 데 적합할 것으로 판단된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.87-87
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• 2017

Flowering time of either early or late is one of the crucial parameters that determine the crop productivity. Therefore, elucidation of regulatory mechanisms of flowering time should contribute to breeding for yield enhancement. However, comprehensive explanation on molecular mechanism of flowering has not yet been reported in hexaploidy common wheat (Triticum asetivum L.). The mechanism of flowering in wheat has been studied mostly using flag leaf or floral meristem. The exposed peduncle, which is a shoot part between bottom of the spike and flag leaf, could be an important tissue that is responsible for flowering through various molecules expressing. To clarify for transcriptomic dynamics in the wheat peduncle that was uncovered by leaf sheath of flag leaf, RNA sequencing and transcriptomic analysis were conducted. With this, we also analyzed other transcriptomic results deposited in the public DB to identify genes specially expressed in peduncle tissue at transition from vegetative to reproductive phase. The obtained results will provide valuable information to understand the role of peduncle for flowing regulation in wheat aimming for elucidation of the regulatory mechanism of wheat flowering.

• Applied Microscopy
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• 제46권2호
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• pp.83-88
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• 2016

Structural differentiation of the connective stalk in giant duckweed, Spirodela polyrhiza, was examined to reveal the anatomical and ultrastructural characteristics within reduced shoot. The study focuses primarily on structural features of the connective stalk (CT), which connect offspring to their mother fronds. Photoautotrophic offspring fronds remained connected by stalks to mother fronds in the reproductive pockets until separation. The CT originated from the meristematic region of the abaxial frond and joined the fronds laterally with two abscission layers. The most notable features of the CT were polymorphic mitochondria, random occurrences of fibrillar structures in intercellular spaces, and great variability in cell wall thickness. Vascular tissues in CTs were highly reduced, demonstrating only a central vascular strand. Grana with 2 to 4 thylakoids and starch grains were found in the chloroplasts. A chlorophyll assay indicated high chlorophyll concentrations in daughter fronds and low concentrations in CTs. The frond and CT, while physically connected to each other, functioned independently. Despite great reduction in S. polyrhiza, the CT has proven to be very efficient for separating offspring from the mother frond, which lends to its capacity for rapid vegetative reproduction. The ultrastructural aspects of CTs in S. polyrhiza were characterized for the first time in this study.

• ALGAE
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• 제28권2호
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• pp.161-171
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• 2013

A morphologically distinct lineage within the Bostrychia moritziana-B. radicans species complex is described as a new species. Bostrychia anomala has thalli with branched monosiphonous filaments with apical cell divisions. The species has terminal tetrasporangial stichidia, each subtending cell bearing tetrasporangia with 2 cover cells. Discharged spores divide transversely, the lower cell first forming a narrow rhizoid and the upper cell forming a monosiphonous shoot. Females have subterminal procarps and males have terminal spermatangial stichidia. Carposporophytes are spherical. Isolates in culture show a pattern of cell death not associated with injury, reminiscent of programmed cell death. Bostrychia anomola shows cell death at intervals along the filaments resulting in division of adjacent cells on either side of the dead cell re-joining the filament; cell division of only one adjacent cell resulting in branching at that site; or filaments fragmenting at the cell death point with adjacent cells forming new apical cells, a means of thallus propagation. The cell death pattern could be a method of filament propagation in the mangrove environment where sexual reproduction is rare.