• Title/Summary/Keyword: RGR

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Effects of Climatic Factors varied due to the Type of Plastic House, Cultural Season and Locations in the Plastic House on the Growth of Cucumber Plants Grown in Rockwool (Plastic house의 형태, 재배양식 및 시설내 위치에 따른 기상환경의 차이가 암면재배 오이의 생장에 미치는 영향)

  • Lim Jung-Mook;Kwon Byung-Sun;Shin Dong-Young;Hyun Kyu-Hwan;Kim Hak-Jin;Chung Soon-Ju;Lee Beom-Seon;Lim June-Taeg
    • Korean Journal of Plant Resources
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    • v.19 no.2
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    • pp.218-222
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    • 2006
  • This experiment was conducted to investigate the effects of climatic factors varied due to the type of plastic house, cultural season and location in the house on the growth of cucumber plants grown by nutrient solution. There were two growing periods, summer culture and retarding culture, two types of plastic houses, 1-2W type house and post-less house. Air temperature, relative humidity and amount of solar radiation in the plastic houses were measured. Also, dry weight of leaves and stems, plant height, number of leaves per plant, leaf area per plant and fresh weight of fruits per plant were observed. Plant growth analysis were conducted and interrelationships between climatic factors and physiological characteristics were investigated. The results were as follows. There were no differences between the type of plastic houses in the average air temperature and average relative humidity in the plastic house, but amount of solar radiation in 1-2W type house was significantly higher than that of postless house. Daily cumulative solar radiation were highest in southwest side of 1-2W type house and northwest side of postless house. Plant height and number of leaves per plant were higher in summer culture than retarding culture, while leaf area per plant was higher in retarding culture than summer culture. Relative growth rate (RGR) showed highly significantly positive correlations with net assimilation rate (WAR) and leaf area ratio (LAR). Contribution of NAR to RGR was much higher than that of LAR. Crop growth rate (CGR) showed highly significantly positive correlations with leaf area index (LAI). It appeared that increase of LAI was important to increase productivity of cucumber. Average daily air temperature for the whole growing period showed highly significantly positive correlations with RGR and NAR. Furthermore, cumulative solar radiation for the whole growing period in retarded culture showed significantly positive correlation with RGR and NAR.

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.

Effects of Temperature and Irrigation Intervals on Photosynthesis, Growth and Growth Analysis of Pot-grown Cucumber Seedlings (온도와 관수 주기가 오이 포트 묘의 광합성, 생육 및 생장 해석에 미치는 영향)

  • Jin Hee An;Eun Yong Choi;Yong Beom Lee;Ki Young Choi
    • Journal of Bio-Environment Control
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    • v.32 no.2
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    • pp.148-156
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    • 2023
  • This study was conducted in an indoor cultivation room and chamber where environmental control is possible to investigate the effect of temperature and irrigation interval on photosynthesis, growth and growth analysis of potted seedling cucumber. The light intensity (70 W·m-2) and humidity (65%) were set to be the same. The experimental treatments were six combinations of three different temperatures, 15/10℃, 25/20℃, and 35/25℃, and two irrigation intervals, 100 mL per day (S) and 200 mL every 2 days (L). The treatments were named 15S, 15L, 25S, 25L, 35S, and 35L. Seedlings at 0.5 cm in height were planted in pots (volume:1 L) filled with sandy loam and treated for 21 days. Photosynthesis, transpiration rate and stomatal conductance at 14 days after treatment were highest in 25S. These were higher in S treatments with a shorter irrigation interval than L treatments. Total amount of irrigation water was supplied evenly at 2 L, but the soil moisture content was highest at 15S and lowest at 25S > 15L > 25L, 35S and 35L in that order. Humidity showed a similar trend at 15/10℃ (61.1%) and 25/20℃ (67.2%), but it was as high at 35/25℃ (80.5%). Cucumber growth (plant height, leaf length, leaf width, chlorophyll content, leaf area, fresh weight and dry weight) on day 21 was the highest in 25S. Growth parameters were higher in S with shorter irrigation intervals. Yellow symptom of leaf was occurred in 89.9% at 35S and 35L, where the temperature was high. Relative growth rate (RGR) and specific leaf weight (SLA) were high at 25/20℃ (25S, 25L), RGR tended to be high in the S treatment, and SLA in the L treatment. Water use efficiency (WUE) was high in the order of 25S, 25L > 15S > 15L, 35S, and 35L. As a result of the above, the growth and WUE were high at the temperature of 25/20℃.

Modeling the Growth of Neurology Literature

  • Hadagali, Gururaj S.;Anandhalli, Gavisiddappa
    • Journal of Information Science Theory and Practice
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    • v.3 no.3
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    • pp.45-63
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    • 2015
  • The word ‘growth’ represents an increase in actual size, implying a change of state. In science and technology, growth may imply an increase in number of institutions, scientists, or publications, etc. The present study demonstrates the growth of neurology literature for the period 1961-2010. A total of 291,702 records were extracted from the Science Direct Database for fifty years. The Relative Growth Rate (RGR) and Doubling Time (Dt.) of neurology literature have been calculated, supplementing with different growth patterns to check whether neurology literature fits exponential, linear, or logistic models. The results of the study indicate that the growth of literature in neurology does not follow the linear, or logistic growth model. However, it follows closely the exponential growth model. The study concludes that there has been a consistent trend towards increased growth of literature in the field of neurology.

Studies on the Competition-Density Effect of Some Higher Plants (수종 식물의 밀도-경쟁효과에 관한 연구)

  • 진희성
    • Journal of Plant Biology
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    • v.15 no.2
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    • pp.7-19
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    • 1972
  • The studies of density effect or the effect of population density on plant growth have been done on basis of dry matter production with Raphanus acanthiformis var. simoodaeguen, Brassica campestris var. Pekinensis f. namsounsokoombecheu, Oryza sativa f. kimmajae and O. sativa f. mangyeng grown in the various spacing. 1. In the early period of plant growth in dry weight was not different each other among varying densities, but as time advanced the plant grown vast space grew sufficiently compared with those of narrow one. 2. Iogarithmic relation between the growth of plant (W) and the density (P), log W-log P in the material plants, were approximated by two straight lines, one was horizontal line and another inclined: the former showed non-competition density and the latter competition density addition to these the point interlinking both lines were implied of the optimum density per unit land area at certain growth period. 3. The values of relatvie growth rate (RGR) and net assimilation rate (NAR) were decreased as increase in the density, while those of leaf area ratio (LAR) were rather increased in the same condition, with minor exception. From these results and relation between the productive structure and due to lack of the recieved light intensity owing to the mutal shading among the plants.

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Effect of Fruits Removal on the Photosynthesis and the Growth of Ginseng Plant (Punax ginseng C. A. MEYER) (적예가 인삼의 광합성 및 생육에 미치는 영향)

  • Yang, Deok-Jo;Lee, Seong-Sik;Kim, Yo-Tae
    • Journal of Ginseng Research
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    • v.6 no.1
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    • pp.1-10
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    • 1982
  • This study was conducted to determine effect of fruits removal on the CO2 exchange rates (CER) and growth of ginseng plant. Fruit of 2, 4 age plant removed at 7, May. The results of these investigations are as follows. 1. The net photosynthetic rates of the ginseng bearing fruits increased to a considerably greater degree than that of the ginseng without fruit in each ages. 2. The total dry matter per plant in bearing fruit (40.24g) had produced more dry matter than that of non-fruiting plant (38.13g) , but the root 4.y matter in fruiting plant (26.2g) had produced less dry matter than that of non-fruiting plant (27.1g) in 4 age. 3. The ginseng plant in bearing fruit did not influence the dry matter of stem and leaf. 4. The maximum RGR of root (17, June) was slower than that of fruit (4, June) .

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Study on the Salt Tolerance of Rice and other Crops in Reclaimed Soil Areas 15. The Effects of Salt on the Efficiency of Sunlight Utilization of Rice Canopy in Reclaimed Saline Soils (간척지에서 수도 및 기타 작물의 내염성에 관한 연구 15. 간척지에 재배한 수도 엽층의 수광 효과에 미치는 염분의 영향)

  • 임형빈
    • Journal of Plant Biology
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    • v.14 no.3
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    • pp.60-65
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    • 1971
  • In order to observe the factors affecting light utilization efficiency in the canopy of a rice crop grown in reclaimed saline areas in Korea, 22 varieties of rice were cultured at the average salt concentration of 6.05mmhos/cm $25^{\circ}C$, (0.39%) in saline soils and non-saline silty loam soils. The inhibition of tillering ability by salt damage at the maximum tillering stage was greater than to growth in height. A significant direct correlation was observed between both ratios and salt concentration with each variety. In the salty areas the length of the flag leaf of the maturing stage showed a positive correlation with the production of rough rice while other living leaf showed a negative correlation. LAI of maturing stage was less in the salty area than in the non-salty area, while the former showed higher ratio in net assimilation and translocation to head with greater RGR before and after the heading stage.

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The effect of dry matter allocation at the early seedling stare on the growth of two grass species (두 초본 종의 생장에 있어서 실생 초기의 물질분해 효과)

  • Park, Young-Mok
    • The Korean Journal of Ecology
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    • v.15 no.3
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    • pp.297-309
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    • 1992
  • The growth of digitaria adscendens and eleusine indica, annual weeds common in japan, was experimentally analyzed under varying untrient conditions. compared with e. indica, d. adscendensshowed a higher the two under high nitrogen availability. Higher net assimilation rate(nar) in d. adscendens than e. india was responsible for high RGR in D. adscendens under the low nitrogen availability. The different of NAR in the two species was induced not by leaf nitrogen content but by nitrogen use efficiency. Under unfertilized conditions nitrogen uptake rate(nur) was greater in d. adscendens than e. indica. Specific absorption rate in two species was similar, but root mass was greater in d. adscendens than e. indica.d. adscendens allocated more dry matter to roots than e. india earlier stage of seedlings. The contributed to higher rot mass and in turn resulted in higher nur in d. adscendens than that in e. india. It is concluuded that the larger allocation of dry matter to roots at early seedling stage in d. adscendens plays an important role in obtaining nitrogen for the continuation of growth under low nitrogen availability.

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Studies on Physiological and Ecological Responses of Barley I. Growth Analysis of Barley Varieties under the Constant Temperature Condition (대맥의 물질생산에 관한 기초적연구 I. 일정한 온도환경조건하에서 생육한 대맥품종의 생육해석)

  • Chang-Hwan Cho;Wan-Sik Ahn
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.21 no.1
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    • pp.65-70
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    • 1976
  • To evaluate growth pattern of barley, dry matter productions of two barley varieties with different winter habits were compared under same temperature and day length conditions.

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Impact of Quantitative Feeding on Nutritional Parameters of Fifth Instar Larvae of Antheraea mylitta

  • Rath, Sudhansu Sekhar
    • International Journal of Industrial Entomology and Biomaterials
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    • v.20 no.2
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    • pp.69-74
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    • 2010
  • Feeding is an important aspect of insect nutrition which in turn supports growth, development, reproduction and survival. The impact of quantitative feeding on nutritional parameters of fifth instar Antheraea mylitta larvae was studied by providing fresh leaves of Terminalia tomentosa for 1 to 4 times a day. All the parameters improved upon providing fresh diets more times over the single diet (1FD). The absolute body weight increased with increase in number of feeds/day significantly (P<0.001). While the maximum weight recorded was 29.61 g in 1FD, the respective weights for two feeds/day (2FD), three feeds/day (3FD) and four feeds/day (4FD) were 39.41 g, 40.63 g and 42.66 g respectively. Feeding period and instar duration were declined (P<0.001) and survival increased significantly (P<0.001) upon increase in the number of diets. Nutritional indices like ingestion, digestion, relative consumption rate (RCR), relative growth rate (RGR) and gain in body weight increased significantly with the increase in number of feeds/day, but approximate digestibility (AD) and efficiency of conversion of ingested food (ECI) declined, while efficiency of conversion of digested food (ECD) did not change.