• Journal of Plant Biology
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• 제29권2호
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• pp.109-115
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• 1986

Actinorhizal plants being capable of fixing atmospheric nitrogen in symbiotic association with Frankia were surveyed for their root nodules, and the root nodules were collected for further studies. Three species of Alnus and Elaeagnus (A. hirsuta, a. firma, A. japonica; E. glabra, e. umbellata, E. macrophylla) and one species of Myrica (M. rubura) were confirmed to bear the root nodules of typical external shape. Morphological studies using light microscope and scanning electron microscope revealed the presence of vesicle clusters in the cortex region of the root. Two tentative endophyte colonies were isolated from the root nodule of A. hirsuta.

• Journal of Plant Biology
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• 제38권4호
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• pp.381-388
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• 1995

해녀콩(Canavalia lineata) 뿌리혹으로부터 만들어진 cDNA library를 뿌리의 총 RNA, leghemoglobin 및 uricasell cDNA를 competitor로 사용하여 차등 혼성화반응으로 후기 뿌리혹에서 발현되며 Cno이, Cne2, Cne3, Clb2로 명명된 4개의 cDNA 클론을 얻었다. Cnod1은 벼의 cysteine proteinase를 암호화하는 유전자와 유사한데 1450nt의 전사체외 혼성화 반응을 보였으며 뿌리혹에서만 발현되고 뿌리혹 발달 후기에서 가장 높은 발현을 보였다. Cne2는 벼의 Expressed Sequence Tag의 한 종류와 유사하고 900 nt의 전사체와 혼성화 반응을 보였으며 뿌리혹에서 주로 발현되었다. Cne2는 접종 후 13일째 발현이 증폭된 후 일정하게 유지되었다. Cne2는 완두의 tonoplast 막 내재 단백질 TRG31을 암호화하는 유전자와 유사하며 뿌리에서 가장 많이 발현되었다. Cne3는 1700 nt와 1400 nt의 전사체와 혼성화반응을 보였으며 뿌리혹의 성장, 발달과 일치하는 발현 양상을 보였다. Clb2는 800 nt의 전사체와 혼성화반응을 보였으며 접종 후 8일째부터 발현이 시작되어 13일째 증폭되고 그 이후 일정한 수준을 유지하였다.

• Molecules and Cells
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• 제23권1호
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• pp.115-121
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• 2007

Root nodule formation is controlled by plant hormones such as auxin. Auxin-repressed protein (ARP) genes have been identified in various plant species but their functions are not clear. We have isolated a full-length cDNA clone (EuNOD-ARP1) showing high sequence homology to previously identified ARP genes from root nodules of Elaeagnus umbellata. Genomic Southern hybridization showed that there are at least four ARP-related genes in the genome of E. umbellata. The cDNA clone encodes a polypeptide of 120 amino acid residues with no signal peptide or organelle-targeting signals, indicating that it is a cytosolic protein. Its cytosolic location was confirmed using Arabidopsis protoplasts expressing a EuNOD-ARP1:smGFP fusion protein. Northern hybridization showed that EuNOD-ARP1 expression was higher in root nodules than in leaves or uninoculated roots. Unlike the ARP genes of strawberry and black locust, which are negatively regulated by exogenous auxin, EuNOD-ARP1 expression is induced by auxin in leaf tissue of E. umbellata. In situ hybridization revealed that EuNOD-ARP1 is mainly expressed in the fixation zone of root nodules.

• 미생물학회지
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• 제27권4호
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• pp.398-403
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• 1989

The root nodule of Canavalia lineta was classified as a determinate nodule and the symbiont as a Rhizobium-bacteriod based on their morphological characteristics. Isolated encosymbiont was similar both to R. leguminosarum and R. meliloti in its peritrichous arrangement of flagella and some of the physiological characteristics. Compared to control plants, Canavalia seedlings inoculated with the isolate grew normally due to induced root nodules, confirming isolate's infectivity and effectivity. Characteristics of the reisolated endosymbiont from induced root nodule were identical to those of the first isolate, indicating the nodules were induced by the first isolate. From these results, it was confirmed that Rhizobium strain isolated from the root nodules of Canavalia lineata was a real symbiont, and was named Rhizobium sp. SNU003.

• 미생물학회지
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• 제29권2호
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• pp.143-147
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• 1991

The root nodules and Glycine max were classified as determinate nodule based on their morphological characteristics, and isolated endosymbiont as a Bradyrhizobium based on its growth rate and single subpolar flagellum. The isolate was similar to B. japonicum USDA110 in utilization of carbon source, growth at 38.deg.C and 2% NaCl, production of $H_{2}$S and especially in the restriction endonuclease digestion pattern of symbiotic genes, allowing them to be placed in sTI group together. The former, however, grew better than the later in broad pH range from 5.0 to 9.5. Infectivity and effectivity of the isolate were confirmed by inoculation of soybean seedlings with the isolates. Characteristics of the reisolated endosymbiont from induced root nodules were identical to those of the first isolate. From these results, it was confirmed that Bradyrhizobium strain isolated from the root nodules of Glycine max was a real symbiont, and was named B. japonicum SNU001.

• 한국토양비료학회지
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• 제15권4호
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• pp.277-283
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• 1982

대두(大豆) 근류(根瘤)로부터의 질소고정능(窒素固定能)을 아세치렌 환원법(還元法)($C_2H_2-C_2H_4$)으로 측정(測定)할 경우(境遇)의 실험방법) 및 대두(大豆) 생육기간중(生育期間中) 근류(根瘤)로부터 고정(固定)되는 질소량(窒素量)을 파악하고져 pot 및 실내실험으로 수행(遂行)하였든 바 다음과 같은 결과(結果)를 얻었다. 1. 아세치렌 환원법(還元法)으로 근류(根瘤)의 질소고정능(室素固定能)을 측정(測定)할 경우(境遇), 근류(根瘤)를 뿌리에 붙은 상태(狀態)로 측정(測定)하면 아세치렌 충전후(充塡後) 항온(恒溫) 2시간(時間)에 측정(測定)하는것이 이상적(理想的)이었으며, 근류(根瘤)를 분산(分離)시키면 측정치(測定値)의 경시적 변동이 컸다. 2. 대두(大豆) 파종후(播種後) 근류형성량(根瘤形成量)은 55일(日), 질소고정량(室素固定量)은 40일(日)까지 직선적(直線的)으로 증가되었으나 그 이후(以後)부터는 감소(減少)되는 경향(傾向)이었다. 3. pot에서 대두(大豆) 1작기(作期) 생육기간중(生育期間中) 근류(根瘤)에 의(依)한 질소고정량(窒素固定量)은 반당(11,100본위모(本立毛)) 약(約) 8.0kg/10a로 추정(推定)되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.358-358
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• 2017

The plant type is generally one of the most important factor for crop production and be influenced by nitrogen absorption. Soybean plants have nodules in their roots, supplying nitrogen at the vegetative and reproductive stages. Root nodules seem to effect plant type of soybean plants, but there are few reports on the relation nodules and plant type. We tried to clarify the effects of root nodules on the plant type, especially internode length and petiole length, comparing non-nodule soybean with normal soybean. The pot experiment and field experiment were carried out at Mie University and Utsunomiya University in 2015 and 2016. Enrei, a popular cultivar in central Japan, and En1282, non-nodulating isogenic line of Enrei, were used. The petiole length on main stem was measured after defoliation and internode length and yield components were measured after harvest. In the field experiment, the patterns of the final length in internode and petiole on main stem were consistent in both cultivars, and a positive correlation was found between the Nth petiole length and the N-1th internode length, belong to the same phytomere. Therefore, the petiole and internode on the main stem make similar response for environmental factors. In pot experiment, Enrei grew with the same pattern as field experiments, but in En1282, the elongation of petiole and internode in the upper part was suppressed, especially the petiole was suppressed greatly. The main stem becomes the basis of the plant type. These results were considered that the nitrogen is distributed preferentially to the internode than the petiole. It seems that the pot cultivation restricted the rhizosphere and caused nitrogen deficiency in En1282. These results suggested that the slight nitrogen deficiency provided from the root nodules was compensated by the increase of the amount of inorganic nitrogen absorption due to the expansion of the rhizosphere, and the severe nitrogen deficiency suppressed elongation of petiole and internode. It is clear that root nodules effect the plant type by supplying nitrogen to internodes and petioles.

• 한국초지조사료학회지
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• 제14권3호
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• pp.177-185
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• 1994

Slow seedling growth rate and nodulation failure of white clover (Trifolium repens L.) has been limited its good establishment to pastures. The experiment was done to determine the effect of removal of cotyledon and unifoliolate on the shoot, root growth, and nodule formation of 4 white clover cultivars for 8 weeks after the treatment. Four white clover cv. Regal (large leaf), Louisiana S-I (medium-large leaf), Grasslands Huia (mediumsmall leaf), and Aberystwyth S184 (small leaf), were grown in IOcm plastic pot containing 2:l:l soi1:sand:peat moss mixture until grown to cotyledon or unifoliolate stage and then removed one (Cl) or two cotyledons (C2) at cotyledon stage, and unifoliolate only (U), unifoliolate and one cotyledon (UCl) or unifoliolate and two cotyledons (UC2) at the unifoliolate stage, and the plants were sampled at 4, 6 and 8 weeks after the treatments. The intact plants had greater shoot and root dry weights, and no. of nodules than removal-treated ones. Removal treatments at cotyledon stage, the dry weight and no. of nodules more decreased in C1 and C2 than that of unifoliolate stage. While the severer cotyledon removal, the more reduction. Although the dry weights and no. of nodules steadily inclined with regrowing period, the former were higher in Regal and La. S-1 than in the others since 6 weeks after removal treatment but the latter was more in S 184 than in the others 8 weeks after removal treatment. Relationship between no. of nodules and shoot or root dry weight was analysed as linear mode while the earlier and severe removal, the steeper slope. It was concluded that severer damage of cotyledon and unifoliolate had detrimental effects on the shoot and root growth, nodule formation, and aftermath establishment of white clover.

• 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.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1986년도 춘계 학술대회지
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• pp.62-63
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• 1986