• Title/Summary/Keyword: relative growth rate(RGR)

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Interactive Effects of Ozone and Light Intensity on Platanus occidentalis L. Seedlings

  • Kim, Du-Hyun;Han, Sim-Hee;Lee, Kab-Yeon;Kim, Pan-Gi
    • Journal of Korean Society of Forest Science
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    • v.97 no.5
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    • pp.508-515
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    • 2008
  • Sycamore (Platanus occidentalis L.) seedlings were grown under low light intensity and ozone treatments to investigate the role of the light environment in their response to chronic ozone stress. One-year-old seedlings of Platanus occidentalis L. were grown in pots for 3 weeks under low light (OL, $150{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and high light (OH, $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) irradiance in combination with 150 ppb of ozone fumigation. After three weeks of ozone and light treatment, seedlings were placed in ozone free clean chamber for 3 weeks for recovery from ozone stress with same light conditions to compare recovery capacity. Ozone fumigation determined an impairment of the photosynthetic process. Reduction of leaf dry weight (14%) and shoo/root ratio (17%) were observed in OH treatment. OL treatment also showed severe reductions in leaf dry weight and shoot/root ratio by 48% and 36% comparing to control, respectively. At the recovery phase, OH-treated plants recovered their biomass, whereas OL-treated plant showed reduction in leaf dry weight (52%) and shoot/root ratio (49%). OH-treated plants reached similar relative growth rate (RGR) comparing to control, whereas OL-treated plants showed lower RGR in stem height. However, there were no significant differences in response to those treatments in stem diameter RGR at the recovery phase. Ozone treatment produced significant reduction of net photosynthesis in both high and low light treatments. Carboxylation efficiency and apparent quantum yield in OL-treated plants showed significant reductions rate to 10% and 45%, respectively. At the recovery stage, ozone exposed seedlings under high light had similar photosynthetic capacity comparing to control plants. Antioxidant enzymes activities such as superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR) were increased in ozone fumigated plants only under low light. The present work shows that the physiological changes occur in photosynthesis-related parameters and growth due to ozone and low light stress. Thus, low light seems to enhance the detrimental effects of ozone on growth, photosynthesis, and antioxidant enzyme responses.

Studies on the Growth of Bidens L. Along the Environmental Gradient (환경구배에 따른 Bidens L.속 식물의 성장에 관한 연구)

  • 최상규;양금철
    • Korean Journal of Environmental Biology
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    • v.22 no.1
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    • pp.101-110
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    • 2004
  • The growth and niche breath of four species, i.e., native plants such as Bidens tripauita and B. bipinnata and naturalized plants such as B. frondosa and B. pilosa var. minor, were studied as related with environmental gradients including light intensity, soil moisture and soil nutrient. There were no significant differences in the phonology within each environmental gradients while considerable differences were found between species; the two naturalized species bloomed and produced fruit later than the two native species. Two naturalized species exhibited relatively higher total dry weight than the two native counterparts within all environmental gradients. Total dry weight showed positive responses to light intensity and soil moisture, and negatively to soil nutrient. The relative contribution of the environmental factors to total dry weight decreased in the order of soil nutrient, soil moisture and light intensity. Both B. bipinnata and B. pilosa var. minor showed significantly higher net assimilation rate (NAR) than other species. Also, NARs of B. bipinnata and B. pilosa var. minor decreased with increasing soil nutrient. Relative growth rate (RGR) decreased in order of B. tripartita, B. bipinnata, B. frondosa and B. pilosa var. minor in response to light intensity. In addition, RGRs of B. bipinnata and B. piEosa yay. minor increased in response to soil moisture, while those of B. pilosa var. minor and B. tripartita decreased with increment of soil nutrient. No significant fluctuations of shoot/root ratio were not observed in three species, but a native species, B. tripartita showed n decreased shoot/root ratio in response to soil nutrient. Comparing the growth characteristics of the species, B. pitosa var. minor and 3. tripartita revealed vigorous growth on barren soil. On the other hand, B. frondosa exhibited vigorous growth on fertile soil. Morphologically, B. tripartita adapted to light and required considerable moisture. On the contrary, the leaves of B. bipinnata did not change considerably in their area, although it preferred habitat with abundant light. In terms of niche breadth, B. bipinnata showed the widest ranges of 0.875 and 0.845 for light intensity and soil moisture gradients, respectively. B. pilosa var. minor showed a value of 0.933 for soil nutrient gradient. B. tripartita showed narrow ranges for the three environmental factors, whereas B. frondosa showed wide values for light intensity and soil nutrient, but relatively narrow value for soil moisture.

Effect of Biochar Treatment on the Growth Characteristics of Q. variabilis for the Restoration of Post-fire Forest Areas (산불피해지 복원을 위한 바이오차 처리가 굴참나무 묘목 생육에 미치는 영향)

  • Yu Gyeong Jung;So Jin Kim;Ju Eun Kim;Jeong Hyeon Bae;Won Seok Kang;Young Geun Lee;Ki Hyung Park
    • Journal of Korean Society of Forest Science
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    • v.112 no.3
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    • pp.290-302
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    • 2023
  • The aim of this study was to examine the changes in the initial tree growth characteristics of Q. variabilis planted in forest fire-damaged areas treated with soil moisturizers such as biochar and to identify the factors that affect tree growth. To evaluate the effectiveness of soil moisture treatment in the area planted with QV, an experimental plot was created according to the treatment method (spread and mix) and treatment ratio (0, 4, and 40 t/ha). The survival rate of QV was 20% higher in the treatment plot than in the control plot. The height and root collar diameter (RCD)growths of QV were high on the northern slope with spread treatment and on the southern slope with mix treatment. The relative growth rate (RGR) according to the soil moisturizer treatment method was higher in the mix treatment, showing a significant difference in RCD. The northern slope had a higher RGR and significant growth rate. This suggests that the growth improvement effect may depend on the soil moisturizer treatment method. The aspect or treatment method affectsthe drying conditions of the soil, which in turn affects its moisture content or nutrient dynamics. The present research results can be used to establish soil moisturizer treatment standards that are suitable for growth purposes. In addition, this study demonstrates that biochar treatment can be considered as an effective alternative to boost biomass and facilitate early restoration of forest fire-damaged areas.

A Comparative Bibliometric Analysis and Visualization of Indian and South Korean Library and Information Science Research Publications During 2001-2020

  • Kappi, Mallikarjun;Biradar, B.S.
    • International Journal of Knowledge Content Development & Technology
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    • v.12 no.4
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    • pp.67-94
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    • 2022
  • The paper aims to present a comparative analysis of scholarly research output in the fields of Library and Information Science (LIS) in India and South Korea. The Web of Science database was used to retrieve the bibliographic data of the Indian and South Korean LIS published documents during 2001-2020 and the indicators were included in the analysis: research productivity, publication-quality, most prolific authors, institutions and journals, "Annual Growth Rate (AGR)", "Compound Annual Growth Rate (CAGR)", "Relative Growth Rate (RGR)", and "Doubling Time (DT)". All types of documents such as articles, conference papers, book reviews, corrections, editorial materials, so on were included in the study. MS Excel, VOS viewer, and bibliometrix (R-tool) software were used for tabulation and mapping. The results show that South Korea placed the top in the overall output of LIS research publications during the last two decades. The Indian LIS research output, Annual Growth Rate (AGR), and Compound Annual Growth Rate (CAGR) were good compared to South Korean LIS publications. In addition, the South Korean LIS researchers' output has increased rapidly in terms of publications, citations, average citations. Gangan Prathap (India), Seyoung Lee, and Heejin Lee (SK) are the most prolific authors; Indian Institute Technology, Delhi and Yonsei University, Seoul are the most prolific institutions; and the Scientometrics journal was the most preferred journal by the Indian and South Korean LIS researchers during the study period. The results of this study are useful to administrators, policymakers, and academics. In addition, the scope of this study might include looking at research published by LIS scholars in India and South Korea, as well as examining all types of academic publications.

Impact of Nosema sp. Infection on Nutritional Physiology and Growth of the Tasar Silkworm Antheraea mylitta

  • Rath, Sudhansu Sekhar;Singh, Mrinal Kanti;Suryanarayana, N
    • International Journal of Industrial Entomology and Biomaterials
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    • v.19 no.2
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    • pp.221-228
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    • 2009
  • Nosema sp. infection in the Indian tasar silkworm, Antheraea mylitta exerts a complex of influences on its host. The instar duration was extended significantly (P<0.001) except in $1^{st}$ instar. The infected larvae took about 48 days to reach the spinning stage against 40 days in the uninfected ones. The final weight attained by the larva at the end of each instar of development declined significantly following infection, as did weight gain and relative growth rate (RGR). The growth recorded/ day declined in infected larvae compared to uninfected ones from 8.2% during $1^{st}$ instar to 43.3% during $5^{th}$ instar. Food ingestion and digestion increased with advancement of the instar significantly irrespective of the status of the larvae but the relative consumption rate (RCR) declined. These parameters significantly declined in infected larvae (except food digested during $2^{nd}$ instar). The decline was more during $3^{rd}$ instar. In contrast, the approximate digestibility (AD %) was significantly higher in infected larvae than uninfected ones leaving the $1^{st}$ instar larvae unaffected. The efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) did not change in a patterned way following the microsporidia (Nosema sp.) infection. The values of ECI significantly changed during $2^{nd}$, $3^{rd}$ and $5^{th}$ instars; while the change in ECD during $2^{nd}$, $4^{th}$ and $5^{th}$ were significant. During the entire larval life all the parameters tends to decline significantly following microsporidia infection but AD registered a significant increase. Nosema sp. spore concentration has increased 270.7 times during larval development in the course of experimentation.

Study on Quantitative Growth Analysis in Yam(Dioscorea spp.) (마의 생장해석(生長解析)에 관(關)한 연구(硏究))

  • Cho, Ji-Hyoung;Lee, Seong-Phil;Oh, Sei-Myoung
    • Korean Journal of Medicinal Crop Science
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    • v.8 no.4
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    • pp.362-372
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    • 2000
  • This study was conducted to obtain the basic information on the production of high yield and qualitied yam in Andong, major yam-producing district, in Kyongbuk province, using three major Yam cultivars, such as Danma, Jangma and Alata (round type). Alata showed the longest tuber width while Jangma showed the longest tube length. Danma showed the highest tube yield at 2,123 kg/10a. Tubes of Alata had higher dry ratio than those of other cultivars, suggesting that Alata could be used as good processing materials. Characteristics of top parts, such as vine length, leaf number, and lateral vine number showed typical sigmoid curves. Tuber characteristics such as length, width and fresh weight of tuber were linearly increased as the growth period was progressed. Relative growth rate (RGR) for new tuber and stem reached the highest value at 86 DAT (days after transplanting). There were similar tendencies among the cultivars in net assimilation rate (NAR). The highest crop growth rate (CGR) was appeared at 156 DAT regardless of cultivars. In the changes of leaf area ratio (LAR), there were significant differences among three cultivars. LAR were decreased at 86, 106 and 136 DAT for Alata, Danma and Jangma, respectively. However, specific leaf weight (SLW) was greatly increased at 176 DAT, and leaf area index (LAI) was decreased at 156 DAT in all cultivars.

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Relationship between Nodulating Characters and Yield Components in Supernodulating Soybean Mutants

  • Park Sei Joon;Youn Jong Tag;Kim Wook Han;Lee Jae Eun;Kwon Young Up;Shin Jin Chul;Seong Rak Chun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.1
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    • pp.5-10
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    • 2005
  • This experiment was conducted to clarify the functions of supernodulating characters on seed yield determination through the comparison of agricultural traits of supernodulating soybean mutants, Sakukei4, SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2. The plant dry weights of supernodulating mutants, Sakukei4 and SS2-2, were $52\%$ and $61\%$ of their wild type parents at full seed stage (R6). However, the relative growth rate (RGR) from the pod set stage (R3) to R6 of Sakukei4 was 0.022 g/g/day and that of SS2-2 was 0.016 g/g/day, which were higher than those of their parents. Nodule number and dry weight were increased in two supernodulating mutants by the R6 stage. The nitrogen concentrations of leaf, petiole and stem of Sakukei4 were higher than those of Enrei. SS2-2 showed higher nitrogen concentration in petiole than Shinpaldalkong2 had. The positive correlations were appeared between nodule dry weight, plant dry weight and pod number, in two supernodulating mutants during the period from R3 to R6 stage. Although all of the yield components and seed yield were lower in two supernodulating mutants than their parents at the stage of full maturity (R8), the harvest index was higher in supernodulating mutants. The increasing rates of pod number to stem dry weight in two supernodulating mutants showed the higher than those of two their parents at R8 stage. In conclusion, the relative growth rates during the early to the middle reproductive growth period were higher in supernodulating mutants than the wild types. This could be resulted in an increase in pod number. The increase of relative growth rate was the result of the successive supplement of nitrogen source from biological nitrogen fixation (BNF) of nodules during the middle reproductive growth period in supernodulating mutants.

Effect of Mulching Material on the Growth and Quality of Oriental Melon (Cucumis melo L. var. makuwa Mak.) in Protected Cultivation (멀칭재료가 시설참외의 생육과 품질에 미치는 영향)

  • Su Gon Bae;Yong Seub Shin;Il Kweon Yeon;Han Woo Do
    • Journal of Bio-Environment Control
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    • v.10 no.4
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    • pp.237-243
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    • 2001
  • The experiment was conducted to investigate the effect of different mulching materials on the growth and quality of oriental melon in protected cultivation. Soil temperature, plant growth and fruit quality were affected by different mulching materials, clear polyethylene (P.E.) film (control), clear inset between black P.E. film, green P.E. film. and recycled ethylene vinyl acetate (E.V.A.) film. The highest night soil temperature was at 20 cm depth under green P.E. film, but was at 5 cm depth under other materials. Difference of soil temperature as affected by mulching materials decreased with increasing soil depth. Plant height, number of nodes, leaf area index (LAI), crop growth rate (CGR), and relative growth rate (RGR) at 30 days after transplanting were significantly greater in the recycled E.V.A. film treatment than in the other treatments. Fresh weight of weeds growth under the mulching materials was not affected by mulching material at 30 days after transplanting. However, it was the greatest under clear P.E. film mulching at 90 days after transplanting. Harvesting time of recycled E.V.A. film was 2 days earlier than that of clear P.E. film. Difference in fruit weight and length, and soluble solid content were not affected by the mulching materials. Marketable yield was 2,426 kg.10a$^{-1}$ in recycled E.V.A. film treatment, which was 6% greater than in clear P.E. film treatment.

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Effect of Nutrient Solution for Hydroponics of Liliaceae Leaf Vegetables on the Amount of Ascorbic Acid in Chinese Chive (백합과 전용배양액이 부추의 Ascorbic acid의 함량에 미치는 영향)

  • Huang, Hua-Zi;Zhang, Cheng-Hao;Yang, Eun-Young;Lee, Sang-Gyu;Choi, Ki-Young;Yun, Hyung-Kweon
    • Journal of Bio-Environment Control
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    • v.16 no.3
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    • pp.222-227
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    • 2007
  • In this study, nutrient solution for Liliaceae (Chinese chive) leafy vegetable was developed. The various strength (1/2, 1 and 3/2) of nutrient solution recommended by National Horticultural Research Institute (NSH) was applied to the crops in deep flow technique (DFT) system for 42 days. The growth of Chinese chive were highest in the treatment of 1/2 strength. The proper constitution of nutrient solution developed for liliaceae crops (NSL) was N 12, P 2.5, K 7, Ca 4 and Mg 2 met. The crops were grown two times in March and September to examine the appropriateness of the NSC. As a result, the relative growth rate and the amount of chlorophyll (SPAD value)of Chinese chive treated with NSL were increased 1.11 times. The most important nutrient factor of ascorbic acid were also increased 1.16 times.

Life history and growth pattern on the erigeron annuus (개망초 ( Erigeron annuus L. ) 의 生活史 및 生育特性)

  • Lee, Ho-Joon;Tae-Sung Kim
    • The Korean Journal of Ecology
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    • v.14 no.2
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    • pp.211-230
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    • 1991
  • The germinatin of e. annuus continued from the middle ofmay to mid-october. The maximum germination occurred on the mid-july. The period bloom of was distingushed amongs the different growth forms ; a orm pr of biennial and a form of pr perennial flowering from the mid-may to mid-september, and a form ps biennial blossom from the beginning of October to earlynovember. the dispersal of seed for(a form pr)occurred from early June to the mid-september. A rotte, germinating from summer to autumn, could classified into several growth forms; individuals without a critical leaf area for bolting until september and October, become a form ps of biennial, whicth did not proceed toreproductive growth unitl the next year, even thought wintering. individuals flowered on 3 years after germination become a form pr of perennial. The growth formular of aform pr of bennial, grown in a pot was w=20.2[1+$3.36{\times}10^3$(-0.062t)]$^{-1}$. The maximum relative growth rate(rgr) was 0.062g/g/day and the maximum net assimlation rate(nar) 0.089g/g/day. Therelative growth among each organ was shown as R=0.12 $T^{1.15}$between the avove-ground part(t) and the below- ground part(r). the relation between the avove-ground part(t) and the ratio of stem weight(wi) was ws/wi=2.56 $T^{0.35}$. n.p.k. was largely distributed on a leaf throughoutthe total growth period. while growing, it tended to decrease on the vegetative organ gut vice versa on the reproductive organ. however, nitrogen was more widely distributed on a leaf then in the reproductive organ.

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