• 한국양식학회지
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• 제16권1호
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• pp.37-43
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• 2003

The present study reports morphology and developmental pattern off siliquosa cultured in a laboratory condition. The zygote was spherical with a diameter of 85 ${\mu}{\textrm}{m}$. During development the polarized zygote divided horizontally and the lower daughter cell divided horizontally into 2 cells. The upper cell was divided repeatedly in horizontal and vertical directions to form a cylinder-like structure, which subsequently developed into secondary and tertiary dichotomous branches. Optimum temperature for zygote release and fertilization was 25C. Injury inflicted by slicing was cured by epidermal differentiation, and adventitious branches; the branches emerging from the pith cells, however, developed no rhizoid. Adventitious branch formation rate was over 88% in all plates supplemented with 0.5 mg/L IAA and peaked at 98% under 0.5 mg/L IAA plus 0.5-5.0 mg/L NAA treatment. NAA stimulated the differentiation of adventitious branches at a wide range of concentrations, while IAA, 2,4-D and kinetin exhibited dose-dependent stimulation.

• 수산해양교육연구
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• 제23권1호
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• pp.126-129
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• 2011

Vegetative morphological information of the red alga Neorhodomela larix (Turner) Masuda (Rhodomelaceae) is given. This species is characterized by thalli up to 15 cm high, brownish black in color, pericentral cells with transverse division, the first order subulate branches with determinate growth, numerous adventitious branches produced at axils and absence of vegetative trichoblasts. Particularly, N. larix is distinct from other Korean Neorhodomela species by the lack of vegetative trichoblasts, which seems to be caused by their delayed production until reproductive structures are formed. This is the first record of N. larix in Korea.

• Journal of Ecology and Environment
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• 제36권4호
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• pp.439-448
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• 2013

Rhodophyta is one of major groups in the number of species and diversity of the marine algal flora. The occurrence of Korean 5 red algal species is reported for the first time on the list of Korean marine algal flora based on morphology: Ceramium pacificum, Cumathanmnion serrulatum, Gayliella fimbriata, Leptofauchea rhodymenioides, Sorella pulchra. Ceramium pacificum from Korea is recognized by complete cortication, many adventitious branches in a radial arrangement, 7-8 periaxial cells, and plant length of 1-2 cm. Cumathanmnion serrulatum is characterized by cartilaginous single main axis with a prominent midrib, serrulate blade, many higher orders of bladelets on each blade, and tetrasporagia produced near the midrib acropetally and then outwardly. Gayliella fimbriata is featured by clavate gland cell and 5-7 periaxial cells. Leptofauchea rhodymenioides is characterized by erect with flattened, dichotomously branched fronds, 1-2 cortical cells loosely arranged, 2-3 cell medullar layers with large colourless cells. Sorella pulchrais recognized by short branches produced alternately pinnate manner from margins of axial, mostly polystromatic frond, and tetrasporangial sori on the center of branches.

• ALGAE
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• 제19권4호
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• pp.283-292
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• 2004

Psilothallia is a ceramiaceous red algal. genus that includes three species worldwide: P. dentate, P. siliculosa, and P. striate. The latter two species are limited to Australian waters, and P. dentate occurs in Japan. We here report the detailed morphology of P. dentate, and also determined plastid protein-coding psbA in P. dentate and putative relatives. Psilothallia dentate is distinguished by compressed thalli with alternate-distichous determinate branchlets, six periaxial cells, rhizoidal filaments in axes, cystocarps with 7-8 involucral filaments, spermatangia on branched filaments, and tetrahedrally divided tetrasporangia on branched filaments. Psilothallia dentate is also unusual in that cystocarps, spermatangial clusters, and tetrasporangial tufts are formed on short adventitious indeterminate branches arising on axils of determinate branchlets. The phylogenetic trees of psbA sequences show that P. dentata was nested in a monophyletic Glade comprising Ptilota, Neoptilota, and Plumaria. This result suggests that the taxonomic position of P. dentate may be transferred from the tribe Rhodocallideae to the Ptiloteae.

• 한국작물학회지
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• 제49권4호
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• pp.316-324
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• 2004

Sinorhizobium sp. strain MUS10 forms nitrogen-fixing stem nodules on Sesbania rostrata, a tropical green manure crop. In this study, the ultrastructural events associated with the formation of stem nodules were investigated. Sinorhizobium sp. strain MUS10 entered the host tissue through cracks created by the emerging adventitious root primordia and multiplied within the intercellular spaces. During early phases of infection, host cells adjacent to invading bacteria revealed cellular damage that is typical of hypersensitive reactions, while the cells at the inner cortex exhibited meristematic activity. Infection threads were numerous in S-day-old nodules and often were associated with the host cell wall. In several cases, more than one infection thread was found in individual cells. The junction at which the host cell walls converged was often enlarged due to fusion of intracellular branches of infection threads resulting in large infection pockets. The infection threads were made up of a homogeneous, amorphous matrix that enclosed the bacteria. Several finger-like projections were seen radiating from these enlarged infection threads and were delineated from the host cytoplasm by the plasma membrane. As in Azorhizobium caulinodans induced root nodules, the release of Sinorhizobia from the infection threads into the plant cells appears to be mediated by 'infection droplets'. A 15-day­old Sesbania stem nodule revealed typical ultrastructure features of a determinate nodule, containing several bacterioids within symbiosomes.

• 한국산림과학회지
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• 제83권2호
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• pp.148-154
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• 1994

물푸레나무 및 들메나무는 결실주기(結實週期)가 길고 암수 딴 그루이므로 우수개체(優秀個體)를 유전자(遺傳子) 변화(變化)없이 대량증식(大量增植) 시킬 수 있는 효과적(效果的)인 삽목(揷木) 등(等) 무성긴식법(無性緊植法)이 요구(要求)된다. 이에 전국(全國)에 산재(散在)한 우수개체(優秀個體)인 수형목(秀型木) 지조(枝條)를 채취(採取)하여 water culture로 맹아지(萌芽枝)를 유도(誘導)하고 발생(發生)된 맹아지(萌芽枝)와 포지(圃地)에 식재(植栽)된 2년생(年生) 실생묘(實生苗) 맹아지(萌芽枝)를 이용(利用)하여 녹지삽목(綠枝揷木)을 실시(實施)하였다. 물푸레나무 및 들메나무의 평균(平均) 수령(樹齡)은 각각(各各) 45, 50년생(年生)이었는데 길이 30cm, 직경(直徑) 5-15cm의 가지에서 시료당(試料當) 3.5개(個)의 맹아지(萌芽枝)가 발생(發生)하였고, 맹아지(萌芽枝) shoot길이가 10cm 이상(以上)되어 삽목가능(揷木可能)한 맹아지(萌芽枝)는 시료당(試料當) 0.6개(個)이었다. 수령범위(樹齡範圍) 29-100년생(年生)에서 수령(樹齡)과 맹아지(萌芽枝) 발생수(發生數) 및 삽목가능(揷木可能) 본수간(本數間)에 두 수종(樹種) 모두 상관(相關)을 보이지 않았다. 환경요인별(環境要因別) 삽목시험(揷木試驗)에서는 노지(露地)의 경우 물푸레 65%, 들메 63%의 발근율(發根率)을 보였고 온실(溫室)에서는 물푸레나무 84%, 들메나무 89%의 발근율(發根率)을 나타내어 노지삽목(露地揷木)보다 온실삽목(溫室揷木)이 좋았다. 상토별(床土別) 삽목시험(揷木試驗)에서는 펄라이트와 피트모스를 2 : 1로 혼합(混合)한 상토(床土)에서의 발근율(發根率)이 평균(平均) 80% 로 가장 양호(良好)하였다. 삽목묘(揷木苗)의 뿌리발달(發達)에 있어서 비용기(非容器) 삽목묘(揷木苗)와 용기(容器) 삽목묘(揷木苗)의 발근(發根)된 뿌리수(數)는 3.6개(個), 2.9개(個)였고, 근장(根長)은 18.4cm, 12.3cm으로 비용기(非容器) 삽목묘(揷木苗)의 뿌리발달(發達)이 양호(良好)하였다 또한, 같은 조건(條件)에서는 상토공극(床土空隙)이 큰 상토삽목묘(床土揷木苗)(왕사)가 공극(空隙)이 작은 상토(床土)(펄라이트 : 버미큐라이트 : 피트모스= 1 : 1 : 1) 삽목묘(揷木苗)보다 뿌리발달(發達) 및 이듬해 shoot생장(生長)이 왕성(旺盛)하였다.

• Journal of Ginseng Research
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• 제33권1호
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• pp.65-71
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• 2009

This experiment was done to determine the optimum conditions for the induction of tetraploidy in Panax ginseng C. A. Meyer using bud length, temperature and plant growth regulator pretreatments. Highest callus formation was obtained when the medium was inoculated with flower bud in the size of 2-3 mm in length. The optimum temperature for the callus formation was high when treated at $4^{\circ}C$ for 4-5 days. Among the treatments of growth regulators and different concentration, highest callus formation was observed in combination of 5 mg/L 2,4-D and 1 mg/L kinetin for P. ginseng. As a result of flow cytometer analysis, all 7 adventitious roots were confirmed as tetraploidys. Cytological analysis revealed that the chromosome number of tetraploid roots was 96, while that of diploid roots was 48. Tetraploid ginseng roots were inoculated to flower bud size of 2-3 mm in length. The callus formation was optimum when treated with 1 mg/L 2,4-D at $4^{\circ}C$ for 5 days. Compared with control roots, tetraploid roots were thicker and longer and had few lateral branches. Fresh weight of tetraploid roots was relatively higher than the control roots.