• Title/Summary/Keyword: TOXICITY

Search Result 7,475, Processing Time 0.038 seconds

Relationships between Micronutrient Contents in Soils and Crops of Plastic Film House (시설재배 토양과 작물 잎 중의 미량원소 함량 관계)

  • Chung, Jong-Bae;Kim, Bok-Jin;Ryu, Kwan-Sig;Lee, Seung-Ho;Shin, Hyun-Jin;Hwang, Tae-Kyung;Choi, Hee-Youl;Lee, Yong-Woo;Lee, Yoon-Jeong;Kim, Jong-Jib
    • Korean Journal of Environmental Agriculture
    • /
    • v.25 no.3
    • /
    • pp.217-227
    • /
    • 2006
  • Micronutrient status in soils and crops of plastic film house and their relationship were investigated. Total 203 plastic film houses were selected (red pepper, 66; cucumber, 63; tomato, 74) in Yeongnam region and soil and leaf samples were collected. Hot-water extractable B and 0.1 N HCl extractable Cu, Zn, Fe, and Mn in soil samples and total micronutrients in leaf samples were analyzed. Contents Zn, Fe, and Mn in most of the investigated soils were higher than the upper limits of optimum level for general crop cultivation. Contents of Cu in most soils of cucumber and tomato cultivation were higher than the upper limit of optimum level, but Cu contents in about 30% of red pepper cultivation soils were below the sufficient level. Contents of B in most soils of cucumber and tomato were above the sufficient level but in 48% of red pepper cultivation soils B were found to be deficient. Micronutrient contents in leaf of investigated crops were much variable. Contents of B, Fe, and Mn were mostly within the sufficient levels, while in 71% of red pepper samples Cu was under deficient level and in 44% of cucumber samples Cu contents were higher than the upper limit of sufficient level. Contents of Zn in red pepper and cucumber samples were mostly within the sufficient level but in 62% of tomato samples Zn contents were under deficient condition. However, any visible deficiency or toxicity symptoms of micronutrients were not found in the crops. No consistent relationships were found between micronutrient contents in soil and leaf, and this indicates that growth and absorption activity of root and interactions among the nutrients in soil might be important factors in overall micronutrient uptake of crops. For best management of micronutrients in plastic film house, much attention should be focused on the management of soil and plant characteristics which control the micronutrient uptake of crops.

Combined Chemoradiotherapy vs Radiotherapy Alone for Locally Advanced Squamous Cell Carcinoma of the Head and Neck (국소적으로 진행된 두경부 편평상피세포종양의 방사선- 항암화학 병용요법과 방사선단독치료의 비교)

  • Jeong, Hyeon-Ju;Suh, Hyun-Suk;Kim, Chul-Soo;Kim, Re-Hwe;Kim, Sung-Rok
    • Radiation Oncology Journal
    • /
    • v.14 no.1
    • /
    • pp.9-15
    • /
    • 1996
  • Purpose: The traditional approach with surgery and/or radiotherapy(RT) for advanced head and neck cancer Provides anticipated cure rates of $10-65\%$ depending on stages and sites. Recently, combined modality with chemotherapy have been extensively investigated in attempts to improve survival and local control. We retrospectively analysed our experience of 31 patients with advanced head and neck cancer. Materials and Methods : November 1983 to October 1994. 31 Patients with Stage III and IV squamous cell head and neck cancer were treated with RT. Sixteen patients were treated with RT alone, and IS patients were treated with combined RT plus chemotherapy. All patients were treated with 4-MV LINAC and radiation dose ranged from 5000 cGy to 7760 cGy (median 7010 cGy). In combined group, 7 patients were treated with cisplatin plus 5-FU 2 patients were treated with methotrexate plus leucovorin plus 5-FU plus cisplatin or carboplatin, and 6 patients were treated with cisplatin as a radiosensitizer. Results : Median follow up period was 16 months (range 4-134 months). The major responses (CR+PR) were noted in 10 patient ($66.6\%$) of the RT alone group and 14 patient ($93.3\%$) of the chemoradiation group. There was no statistical difference in CR rate between the two groups The overall survival rates at 5 years were $23.4\%$ in the radiation alone group, $23.5\%$ in the chemoradiation group Disease-free survival rates at 3 years were $44.5\%$ in the radiation alone group, $40\%$ in the chemoradiation group. There was no statistical differences in overall survival rates and disease-free survival rates between the two groups. Local recurrences occurred in $71.5\%$ of the radiation alone group, $72.7\%$ of the chemoradiation group and distant metastasis occurred in $14.4\%$ of radiation alone group, $9.1\%$ of the chemoradiation group. The frequencies of complications were comparable in both groups except hematologic toxicity Conclusion : Total response rates in the combined chemotherapy and radiotherapy was relatively higher than radiotherapy alone. But our result failed to show any survival benefit of the combined chemotherapy and radiotherapy. The accrual of large number of patients and long term follow-un may be necessary to confirm the present result of combined chemotherapy and radiotherapy.

  • PDF

The Results of Hvperfractionated Radiation Therapy Combined with Taxol for Paraaortic Node Recurrence in Cervix Cancer (대동맥주위 림프절에 재발된 자궁경부암에서 Taxol을 병행한 과분할 방사선치료의 결과)

  • Kim, Jun-Sang;Jang, Ji-Young;Kim, Jae-Sung;Kim, Sam-Yong;Cho, Moon-June
    • Radiation Oncology Journal
    • /
    • v.18 no.1
    • /
    • pp.27-31
    • /
    • 2000
  • Purpose : The aim of this study was to investigate treatment results, toxicity and efficacy of hypefractionated radiation therapy combined with paclitaxel for paraaortic node recurrence in cervix cancer. Materials and Methods: Between September 1997 to March 1999, 12 patients with paraaortic node recurrence in cervix cancer who previously received radical or postoperative radiotherapy were treated with hypefractionated radiation therapy combined with paclitaxel. Of these, 2 patients who irradiated less than 30 Gy were excluded, 10 patients were eligible for this study. Median age was 51 years. Initial FIGO stage was 1 stage IBI, 2 stage IIA, 7 stage IIB. For initial treatment, 7 patients received radical radiotherapy and 3 received postoperative radiotherapy. The paraaortic field encompassed the gross recurrent disease with superior margin at T12, and inferior margin was between L5 and S1 with gap for previously pelvic radiation field. The radiation field was initially anterior and posterior opposed field followed by both lateral field. The daily dose was 1.2 Gy, twice daily fractions, and total radiotherapy dose was between 50.4 and 60 Gy(median, 58.8 Gy). Concurrent chemotherapy was done with paclitaxel as a radiosensitizer. Dose range was from 20 mg/m$^{3}$ to 30 mg/m$^{3}$ (median, 25 mg/m$^{3}$), and cycle of chemotherapy was from 3 to 6 (median, 4.5 cycle). Follow-up period ranged from 3 to 21 months. Results : Interval between initial diagnosis and paraaortic node recurrence was range from 2 to 63 months (median, 8 months). The 1 year overall survival rate and median survival were 75$\%$ and 9.5 months, respectively. The 1 year disease free survival rate and median disease free survival were 30$\%$ and 7 months, respectively. At 1 month after treatment, 4 (40$\%$) achieved a complete response and 6 (60$\%$) experienced a partial response and all patients showed response above the partial response. There was distant metastasis in 6 patients and pelvic node recurrence In 2 patients after paraaortic node irradiation. There was 2 patients with grade 3 to 4 leukopenla and 8 patients with grade 1 to 2 nausea/ vomiting which was usually tolerable with antlemetic drug. There was no chronic complication in abdomen and pelvis during follow up period. Conclusion : hypefractionated radiation therapy combined with paclitaxel chemotherapy diosensitizer showed high response rate and few complication rate in paraaortic node recurrence in cervix cancer Therefore, present results suggest that hypefractionated radiation therapy combined with paclitaxel chemotherapy can be used as optimal treatment modality in this patients.

  • PDF

Effect of Verapamil on Cellular Uptake of Tc-99m MIBI and Tetrofosmin on Several Cancer Cells (수종의 암세포에서 Verapamil이 Tc-99m MIBI와 Tetrofosmin의 섭취에 미치는 영향)

  • Kim, Dae-Hyun;Yoo, Jung-Ah;Suh, Myung-Rang;Bae, Jin-Ho;Jeong, Shin-Young;Ahn, Byeong-Cheol;Lee, Kyu-Bo;Lee, Jae-Tae
    • The Korean Journal of Nuclear Medicine
    • /
    • v.38 no.1
    • /
    • pp.85-98
    • /
    • 2004
  • Purpose: Cellular uptake of $^{99}mTc$-sestamibi (MIBI) and $^{99}mTc$-tetrofosmin (TF) is low in cancer cells expressing multidrug resistance(MDR) by p-glycoprotein(Pgp) or multidrug related protein(MRP). Verapamil is known to increase cellular uptake of MIBI in MDR cancer cells, but is recently reported to have different effects on tracer uptake in certain cancer cells. This study was prepared to evaluate effects of verapamil on cellular uptake of MIBI and TF in several cancer cells. Materials and Methods: Celluar uptakes of Tc-99m MIBI and TF were measured in erythroleukermia K562 cell, breast cancer MCF7 cell, and human ovarian cancer SK-OV-3 cells, and data were compared with those of doxorubicin-resistant K562(Ad) cells. RT-PCR and Western blot analysis were used for the detection of mdr1 mRNA and Pgp expression, and to observe changes in isotypes of PKC enzyme. Effects of verapamil on MIBI and TF uptake were evaluated at different concentrations upto $200{\mu}M\;at\;1{\times}10^6\;cells/ml\;at\;37^{\circ}C$. Radioactivity in supernatant and pellet was measured with gamma counter to calculate cellular uptake ratio. Toxicity of verapamil was measured with MTT assay. Results: Cellular uptakes of MIBI and TF were increased by time in four cancer cells studied. Co-incubation with verapamil resulted in an increase in uptake of MIBI and TF in K562(Adr) cell at a concentration of $100{\mu}M$ and the maximal increase at $50{\mu}M$ was 10-times to baseline. In contrast, uptakes of MIBI and TF in K562, MCF7, SK-OV3 cells were decreased with verapamil treatment at a concentration over $1{\mu}M$. With a concentration of $200{\mu}M$ verapamil, MIBI and TF uptakes un K562 cells were decreased to 1.5 % and 2.7% of those without verapamil, respectively. Cellular uptakes of MIBI and TF in MCF7 and SK-OV-3 cells were not changed with $10{\mu}M$, but were also decreased with verapamil higher than $10{\mu}M$, resulting 40% and 5% of baseline at $50{\mu}M$. MTT assay of four cells revealed that K562, MCF7, SK-OV3 were not damaged with verapamil at $200{\mu}M$. Conclusion: Although verapamil increases uptake of MIBI and TF in MDR cancer cells, cellular uptakes were further decreased with verapamil in certain cancer cells, which is not related to cytotoxicity of drug. These results suggest that cellular uptakes of both tracers might differ among different cells, and interpretation of changes in tracer uptake with verapamil in vitro should be different when different cell lines are used.

Comparison of the Result of Radiation Alone and Radiation with Daily Low Dose Cisplatin in Management of Locally Advanced Cervical Cancer (국소적으로 진행된 자궁경부암에서 방사선 단독치료와 방사선 및 저용량 Cisplatin 항암화학요법 병용치료의 비교)

  • Kim Hun Jung;Kim Woo Chul;Lee Mee Jo;Kim Chul Su;Song Eun Seop;Loh John J K.
    • Radiation Oncology Journal
    • /
    • v.22 no.3
    • /
    • pp.200-207
    • /
    • 2004
  • Purpose: An analysis was to compare the results of radiation alone with those of radiation with dally low dose cisplatin as a radiation sensitizer in locally advanced cervical cancer. Materials and Methods: A retrospective analysis of 59 patients diagnosed with locally advanced uterine cervix cancer between December 1996 and March 2001 was peformed. Thirty one patients received radiation alone and 28 patients received dally low dose cisplatin, as a radiation sensitizer, and radiation therapy. The median follow-up period was 34 months, ranging from 2.5 to 73 months. The radiation therapy consisted of 4500 cGy external beam irradiation to the whole pelvis (midline block after 3060 cGy), a 900$\~$l,000 cGy boost to the involved parametrium and high dose-rate intracavitary brachytherapy (a total dose of 3,000$\~$3,500 cGy/500 cGy per fraction to point A, twice per week). In the chemoradiation group, 10 mg of daily intravenous cisplatin was given daily from the 1st day of radiation therapy to the 20th day of radiation therapy. According to the FIGO classification, the patients were subdivided into 51 (86.4$\%$) and 8 (13.6$\%$) stages IIB and stage IIIB, respectively. Results: The overall 5 year survival rate was 65.65$\%$ and according to treatment modality were 56.75$\%$ and 73.42$\%$ in the radiation alone and chemoradiation groups, respectively (p=0.180). The 5 year disease-free survival rates were 49.39$\%$ and 63.34$\%$ in the radiation alone and chemoradiatoin groups, respectively (p=0.053), The 5 year locoregional control rates were 52.34$\%$ and 73.58$\%$ in the radiation alone and chemoradiation groups, respectively (p=0.013). The 5 year distant disease-free survival rates were 59.29$\%$ and 81.46$\%$ in the radiation alone and chemoradiation groups, respectively (p=0.477), Treatment related hematologic toxicity were prominent in the chemoradiation group. Leukopenia $\geq$grade) occurred in 3.2$\%$and 28.5$\%$ of the radiation alone and chemoradiation groups, respectively (p=0.02). There were no statistical differences in the incidences of vesical, rectal and small bowel complications between two groups. Conclusion: Radiation therapy with low dose cisplatin did not improve the rates of survival and response rates, but did improve the rate of disease free survival and locoregional control rates In locally advanced cervical cancer. The incidence of bone marrow suppression was higher in the chemoradiation group.

The Role of Intraluminal Brachytherapy in Management of Esophageal Cancer (식도암 치료에 있어 관내근접치료의 역할)

  • Lee Chang Geol;Suh Chang Ok;Kim Gwi Eon;Chu Sung Sil;Chung Eun Ji;Kim Woo Cheol
    • Radiation Oncology Journal
    • /
    • v.13 no.4
    • /
    • pp.331-338
    • /
    • 1995
  • Purpose : To evaluate our clinical experience with the combination of teletherapy and intraluminal brachytherapy in patients with unresectable or inoperable esophageal cancers. Materials and Methods : From Nov 1989 to Mar 1993, twenty patients with esophageal cancer were treated with radical radiotherapy and intraluminal brachytherapy at Yonsei Cancer Center. All patients had squamous histolgy and stage distribution was as follows: stage II, 4($20{\%}$)patients; III, 15 ($75{\%}$)patients; IV, 1($5{\%}$)patients. A dose of S-12Gy/1-3weeks with intraluminal brachytherapy (3-5Gy/fraction) to 5mm from the outside of the esophageal tube using high dose rate Iridium-192 remotely afterloading brachytherapy machine was given 2 weeks after a total dose of 59-64Gy with external radiotherapy. Induction chemotherapy using cisplatin and 5-FU was performed in 13 patients with median 3 cycles(1-6 cycles), Response rate, local control rate, survival and complications were analysed retrospectively. Results : Two-year overall survival rate and median survival were $15.8{\%}$ and 13.5 months. Response rates were as follows complete remission(CR) 5($25{\%}$): partial remission a(PRa) 7($35{\%}$): partial remission b(PRb) 7($35{\%}$), no response(NR) 1($5{\%}$). Patterns of failure were as follows; local failure 13($65{\%}$), local and distant failure 3($15{\%}$), distant failure 0($0{\%}$). Ultimate local control rate was $20{\%}$. Treatment related complications included esophageal ulcer in two patients and esophageal stricture in one. Conclusion : Though poor local conrol rate, median survival was improved as compared with previous results of radiation therapy alone(8months) and chemoradiation combined treatment(11 months) in Yonsei Cancer Center High-dose-rate intraluminal brachytherapy following external irradiation is an effective treatment modality with acceptable toxicity in esophageal cancer.

  • PDF

Concurrent Chemoradiotherapy in Locally Advanced Carcinoma of The Uterine Cervix : A Phase I/II Prospective Study (국소적으로 진행된 자궁경부암의 방사선치료와 복합 항암화학요법의 동시치료 결과)

  • Kang One Chul;Choi Eun Kyung;Chung Weon Kuu;Kim Jong Hoon;Chang Hyesook;Kim Yong Man;Kim Young Tak;Nam Joo Hyun;Mok Jung-Eun;Lee Moo-Song
    • Radiation Oncology Journal
    • /
    • v.16 no.3
    • /
    • pp.311-323
    • /
    • 1998
  • Purpose : Prospective, single arm, Phase I/II clinical trial was performed to assess the efficacy and toxicity of the concurrent chemotherapy and definitive radiotherapy (RT) in patients with previously untreated locally advanced carcinoma of the uterine cervix. Methods and Materials : From Mar 1992 to January 1997, a total of 73 patients with advanced cervical carcinoma were entered on the protocol but 5 patients were excluded in analysis because of patients' refusal of treatment. Their ages ranged from 31 to 77 years, median 58 years. The International Federation of Gynecology and Obstetrics (FIGO) stage distribution was as follows: IIB 46, IIIA 2, IIIB 15 and IVA 5. RT consisted of external beam irradiation to 4,140-5,040 cGy/23-28 fractions plus high dose rate intracavitary treatments to deliver a dose of 30-35 Gy to point A in 6-7 fractions. During the intracavitary treatments parametrial boost was delivered for point B dose of 60 Gy in stage IIB and 65 Gy in stage IIIB. Two cycles of concurrent 5-fluorouracil and cisplatin (FP) chemotherapy (5-fluorouracil 1,000 mg/$m^2$/day continuous infusion for 4 days, day 1-4, 29-32 and cisplatin 20 mg/$m^2$/day intravenous bolus for 3 days day 1-3, 29-31) administered starting on day 1 of RT. Results : The median follow-up was 24 months (range 4-68+). Sixty-four patients were evaluable for survival rate in this protocol: The 5-year actuarial and disease-free survival rate were 52$\%$ and 64$\%$, respectively. The 5-rear actuarial survival for stage IIB and III+IVA patients were 58$\%$ and 36$\%$, respectively The 5-year disease-free survival rate for stage IIB and III+IVA patients were 71$\%$ and 40$\%$, respectively. Of the 68 patients evaluated for patterns of failure, overall recurrence rate was 27.9$\%$ (19/68) : local failure in 5.9$\%$ (4/68), distant metastasis in 10.3$\%$ (7/68) and both in 11.8$\%$ (8/68). Of the 64 patients evaluated for response at one month after the completion of treatment the complete response rate was 78$\%$ (50/64). Concurrent chemoradiation appear to be a well-tolerated regimen but there were two treatment-related deaths. Conclusion : Concurrent chemotherapy of FP with high-dose definitive RT in locally advanced carcinoma of the uterine cervix is feasible and effective with acceptable toxicities. This chemoradiation regimen may offer a modest survival benefit for advanced stage. Further follow-up of these patients will evaluate the impact of this regimen on the long-term local control and their survival.

  • PDF

Pulmonary Mycoses in Immunocompromised Hosts (면역기능저하 환자에서 폐진균증에 대한 임상적 고찰)

  • Suh, Gee-Young;Park, Sang-Joon;Kang, Kyeong-Woo;Koh, Young-Min;Kim, Tae-Sung;Chung, Man-Pyo;Kim, Ho-Joong;Han, Jong-Ho;Choi, Dong-Chull;Song, Jae-Hoon;Kwon, O-Jung;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
    • /
    • v.45 no.6
    • /
    • pp.1199-1213
    • /
    • 1998
  • Background : The number of immunocompromised hosts has been increasing steadily and a new pulmonary infiltrate in these patients is a potentially lethal condition which needs rapid diagnosis and treatment. In this study we sought to examine the clinical manifestations, radiologic findings, and therapeutic outcomes of pulmonary mycoses presenting as a new pulmonary infiltrate in immunocompromised hosts. Method : All cases presenting as a new pulmonary infiltrate in immunocompromised hosts and confirmed to be pulmonary mycoses by pathologic examination or by positive culture from a sterile site between October of 1996 and April of 1998 were included in the study and their chart and radiologic findings were retrospectively reviewed. Results : In all, 14 cases of pulmonary mycoses from 13 patients(male : female ratio = 8 : 5, median age 47 yr) were found. Twelve cases were diagnosed as aspergillosis while two were diagnosed as mucormycosis. Major risk factors for fungal infections were chemotherapy for hematologic malignancy(10 cases) and organ transplant recipients(4 cases). Three cases were receiving empirical amphotericin B at the time of appearance of new lung infiltrates. Cases in the hematologic malignancy group had more prominent symptoms : fever(9/10), cough(6/10), sputum(5/10), dyspnea(4/10), chest pain(5/10). Patients in the organ transplant group had minimal symptoms(p<0.05). On simple chest films, all of the cases presented as single or multiple nodules(6/14) or consolidations(8/14). High resolution computed tomograph showed peri-lesional ground glass opacities(14/14), pleural effusions(5/14), and cavitary changes(7/14). Definitive diagnostic methods were as follows : 10 cases underwent minithoracotomy, 2 underwent video-assisted thoracoscopic surgery, 1 underwent percutaneous needle aspiration and 1 case was diagnosed by culture of abscess fluid. All cases received treatment with amphotericin B with 1 case each being treated with liposomal amphotericin B and itraconazole due to renal toxicity. Lung lesion improved in 12 of 14 patient but 4 patients died before completing therapy. Conclusion : When a new lung infiltrate develops presenting either as a nodule or consolidation in a neutropenic patient with hematologic malignancy or in a transplant recipient, you should always consider pulmonary mycoses as one of the differential diagnosis. By performing aggressive work up and early treatment, we may improve prognosis of these patients.

  • PDF

The Classification System and Information Service for Establishing a National Collaborative R&D Strategy in Infectious Diseases: Focusing on the Classification Model for Overseas Coronavirus R&D Projects (국가 감염병 공동R&D전략 수립을 위한 분류체계 및 정보서비스에 대한 연구: 해외 코로나바이러스 R&D과제의 분류모델을 중심으로)

  • Lee, Doyeon;Lee, Jae-Seong;Jun, Seung-pyo;Kim, Keun-Hwan
    • Journal of Intelligence and Information Systems
    • /
    • v.26 no.3
    • /
    • pp.127-147
    • /
    • 2020
  • The world is suffering from numerous human and economic losses due to the novel coronavirus infection (COVID-19). The Korean government established a strategy to overcome the national infectious disease crisis through research and development. It is difficult to find distinctive features and changes in a specific R&D field when using the existing technical classification or science and technology standard classification. Recently, a few studies have been conducted to establish a classification system to provide information about the investment research areas of infectious diseases in Korea through a comparative analysis of Korea government-funded research projects. However, these studies did not provide the necessary information for establishing cooperative research strategies among countries in the infectious diseases, which is required as an execution plan to achieve the goals of national health security and fostering new growth industries. Therefore, it is inevitable to study information services based on the classification system and classification model for establishing a national collaborative R&D strategy. Seven classification - Diagnosis_biomarker, Drug_discovery, Epidemiology, Evaluation_validation, Mechanism_signaling pathway, Prediction, and Vaccine_therapeutic antibody - systems were derived through reviewing infectious diseases-related national-funded research projects of South Korea. A classification system model was trained by combining Scopus data with a bidirectional RNN model. The classification performance of the final model secured robustness with an accuracy of over 90%. In order to conduct the empirical study, an infectious disease classification system was applied to the coronavirus-related research and development projects of major countries such as the STAR Metrics (National Institutes of Health) and NSF (National Science Foundation) of the United States(US), the CORDIS (Community Research & Development Information Service)of the European Union(EU), and the KAKEN (Database of Grants-in-Aid for Scientific Research) of Japan. It can be seen that the research and development trends of infectious diseases (coronavirus) in major countries are mostly concentrated in the prediction that deals with predicting success for clinical trials at the new drug development stage or predicting toxicity that causes side effects. The intriguing result is that for all of these nations, the portion of national investment in the vaccine_therapeutic antibody, which is recognized as an area of research and development aimed at the development of vaccines and treatments, was also very small (5.1%). It indirectly explained the reason of the poor development of vaccines and treatments. Based on the result of examining the investment status of coronavirus-related research projects through comparative analysis by country, it was found that the US and Japan are relatively evenly investing in all infectious diseases-related research areas, while Europe has relatively large investments in specific research areas such as diagnosis_biomarker. Moreover, the information on major coronavirus-related research organizations in major countries was provided by the classification system, thereby allowing establishing an international collaborative R&D projects.

Studies on Nutrio-physiological Response of Rice Plant to Root Environment (근부환경(根部環境)에 따른 수도(水稻)의 영양생리적(營養生理的) 반응(反應)에 관(關)한 연구(硏究))

  • Park, J.K.;Kim, Y.S.;Oh, W.K.;Park, H.;Yazawa, F.
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.2 no.1
    • /
    • pp.53-68
    • /
    • 1969
  • The nutriophysiological response of rice plant to root environment was investigated with eye observation of root development and rhizosphere in situation. The results may be summarized as follows: 1) The quick decomposition of organic matter, added in low yield soil, caused that the origainal organic matter content was reached very quickly, in spite of it low value. In high yield soil the reverse was seen. 2) In low yield soil root development, root activity and T/R value were very low, whereas addition of organic matter lowered them still wore. This might be contributed to gas bubbles around the root by the decomposition of organic matter. 3) Varietal difference in the response to root environment was clear. Suwon 82 was more susceptible to growth-inhibitine conditions on low-yield soil than Norin 25. 4) Potassium uptake was mostly hindered by organic matter, while some factors in soil hindered mostly posphorus uptake. When the organic matter was added to such soil, the effect of them resulted in multiple interaction. 5) The root activity showed a correlation coeffieient of 0.839, 0.834 and 0.948 at 1% level with the number of root, yield of aerial part and root yield, respectively. At 5% level the root-activity showed correlation-coefficient of 0.751, 0.670 and 0.769 with the uptake of the aerial part of respectively. N, P and K and a correlation-coefficient of 0.729, 0.742 and 0.815 with the uptake of the root of respectively N.P. and K. So especially for K-uptake a high correlation with the root-activity was found. 6) The nitrogen content of the roots in low-yield soil was higher than in high-yield soil, while the content in the upper part showed the reverse. It may suggest ammonium toxicity in the root. In low-yield soil Potassium and Phosphorus content was low in both the root and aerial part, and in the latter particularly in the culm and leaf sheath. 7) The content of reducing sugar, non-recuding sugar, starh and eugar, total carbohydrates in the aerial part of plants in low yield soil was higher than in high yield soil. The content of them, especially of reducing sugar in the roots was lower. It may be caused by abnormal metabolic consumption of sugar in the root. 8) Sulfur content was very high in the aerial part, especially in leaf blade of plants on low yield soil and $P_2O_5/S$ value of the leaf blade was one fifth of that in high yield soil. It suggests a possible toxic effect of sulfate ion on photophosphorization. 9) The high value of $Fe/P_2O_5$ of the aerial part of plants in low yield soil suggests the possible formation of solid $Fe/PO_4$ as a mechanical hindrance for the translocation of nutrients. 10) Translocation of nutrients in the plant was very poor and most nutrients were accumulated in the root in low yield soil. That might contributed to the lack of energy sources and mechanical hindrance. 11) The amount of roots in high yield soil, was greater than that in low yield soil. The in high-yield soil was deep, distribution of the roots whereas in the low-yield soil the root-distribution was mainly in the top-layer. Without application of Nitrogen fertilizer the roots were mainly distributed in the upper 7cm. of topsoil. With 120 kg N/ha. root were more concentrated in the layer between 7cm. and 14cm. depth. The amount of roots increased with the amount of fertilizer applied.

  • PDF