• Title/Summary/Keyword: Relative Growth rate

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Seasonal Growth Patterns of Perennial Ryegrass Varieties IV. Growth analysis in spring growth (Perennial Ryegrass 품종의 계절별 생육특성 IIV. 봄철 생육의 생장해석)

  • 김성규;이주삼;조익환
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.4
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    • pp.226-231
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    • 1992
  • This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.

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Relationship between Climate Factors and Relative Growth of Pinus rigida and Castanea crenata in the Cheongju Area of Chungbuk (충북 청주지역 리기다소나무와 밤나무의 상대 생장률과 기후인자와의 관계)

  • Kim, Kee Dae
    • Journal of Environmental Science International
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    • v.26 no.5
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    • pp.585-590
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    • 2017
  • The Diameter at Breast Height (DBH) provides information about the volume growth of a tree. In this study, we estimated the relative growth rates of Castanea crenata and Pinus rigida as 4.07% and 3.73%, respectively. Although the difference was low, we demonstrated that the growth rate of C. crenata is slightly faster than that of P. rigida. After calculating the relative growth rate for each section, we found that the relative growth of C. crenata decreased with time. However, the relative growth rate of P. rigida showed an overall increase. The gap widths of both species showed an increasing trend. However, the gradient of the two species was different. The gradient of C. crenata was approximately 12.0, but that of P. rigida was approximately 4.7. This means that the volume growth of C. crenata was faster than that of P. rigida during 4 years. However, this was relatively a short period for measuring the volume growth pattern, and we believe that additional useful information can be obtained by conducting long-term ecological monitoring. Results of canonical correspondence analysis showed that among the climate variables, temperature was significantly related to the gap widths for both species.

Effects of Water Deficit on Leaf Growth during Vegetative Growth Period in Soybean

  • Kim, Wook-Han;Hong, Byung-Hee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.1
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    • pp.1-5
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    • 2000
  • Leaf area is critical for crop light interception, and thereby has a substantial influence on crop yield. This experiment was conducted to characterize the development of soybean [Glycine max (L.) Merr.] leaf area. Plastochron index and leaf relative growth rate of Jackson was contrasted with the PI416937, which also has demonstrated tolerance to drought. First, plastochron ratio (PR) and plastochron index (PI) were evaluated in greenhouse to compare the leaf growth rate between two genotypes under well-watered condition. There was reasonable constancy of PR between two genotypes. The PR means of Jackson and PI416937 were 0.41 and 0.44, respectively. A fairly smooth increase of PI during vegetative stage was observed. Second, the relative growth rates were graphed against leaf area, normalized with respect to final leaf area, under well-watered and water-deficit conditions. Leaf growth was sustained longer in well-watered condition than water-deficit condition and there was a sizable proportion of leaves which was ceased earlier their growth in water-deficit condition compared to well-watered condition. The leaf relative growth rate of Jackson until leaves had completed at 45% of their growth during water deficit period was higher than that of PI416937.

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Comparison of Growth Performances in Seedling of Allium microdictyon Prokh. and Allium ochotense Prokh. (산마늘과 울릉산마늘 유묘의 생장특성 비교)

  • Lee,K.C.;Kim,H.S.;Han,S.K.;Lee,K.M.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.19 no.1
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    • pp.129-137
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    • 2017
  • This study was conducted to investigate of growth performances and net assimilation rate(NAR) of Allium microdictyon Prokh. distributed inland and Allium ochotense Prokh. originated Ulleung-do. The Allium microdictyon on the growth of 1-2 years showed the largest relative growth rate, and showed high relative growth from three to four years. Allium ochotense on the growth from one year to three years showed high relative growth rate. The T/R rate of Allium ochotense of 2~5years was in the range of 0.4~0.5. However, The T/R rate of Allium microdictyon was increased as increasing with age. This implies that Allium microdictyon was consumed more energy on growing subterranean part. The LWR of 1~3years old Allium ochotense. was showed more smaller than 4~5years old. It seems that the growth characteristics of Allium ochotense 1-3 years after sowing the leaf growth consume more energy than Allium microdictyon. Net assimilation rate(NAR) of Allium ochotense for 1-3 years after sowing was higher than that of Allium microdictyon. In this time, the material of Allium ochotense has a higher production efficiency can be seen indirectly.

Effect of forest restoration treatment on Abies holophylla growth and soil condition: Focusing on the Daegwallyeong alpine pastures

  • Ju-Eun Kim;Jeong-Hyeon Bae;So-Jin Kim;Ki-Hyung Park;Namin Koo;Won-Seok Kang;YuGyeong Jung
    • Korean Journal of Agricultural Science
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    • v.51 no.1
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    • pp.25-39
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    • 2024
  • This study aimed to determine a method for restoring grasslands to forests in mountainous areas. The study was conducted in an area damaged by trampling due to construction activity and herding. Additionally, there were concerns of hindered tree growth due to the alpine region climate, characterized by the low temperatures, drying, and strong winds. Therefore, forest restoration treatments such as tillage, furrow, and shading were performed to improve growth conditions. From July 2021 to April 2023, soil temperature and moisture were monitored for each treatment plot, and changes in the initial growth and survival rate of Abies holophylla were investigated. Both soil temperature and soil moisture showed significantly higher values during the four seasons in the grassland-furrow treatment plot (p < 0.05). Compared to the grassland-control plot, the average soil temperature in winter was as high as 1.1℃, and the soil moisture in summer was as high as 20.3%. Additionally, the survival rate and relative growth rate were the largest in the grassland-furrow treatment plot. The survival rate was 87.5%, the relative growth rate in terms of height was 0.013, and the relative growth rate in terms of diameter at root collar was 0.023, indicating that furrow treatment had a positive effect on the initial survival and growth of seedlings. These results suggest that furrow treatment may be an appropriate restoration method when implementing forest restoration projects in areas where tree growth is challenged.

Influence of Temperature and Relative Humidity in Infection of Nosema bombycis (Microsporidia: Nosematidae) and Cross-infection of N. mylitta on Growth and Development of Mulberry Silkworm, Bombyx mori

  • Chakrabarti, Satadal;Manna, Buddhadeb
    • International Journal of Industrial Entomology and Biomaterials
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    • v.17 no.2
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    • pp.173-180
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    • 2008
  • The influence of temperature and relative humidity in infection and cross-infection of Nosema bombycis and N. mylitta respectively in mulberry silkworm, Bombyx mori L. on larval mortality, multiplication of pathogens, larval weight and growth rate in three different seasons were studied. Seasons were selected in such condition, when very less fluctuations between minimum and maximum temperature and minimum and maximum relative humidity ($25{\sim}28^{\circ}C$ and $65{\sim}72%$ R.H) was observed i.e., season-1. Fluctuations between minimum and maximum temperature were less ($28.05{\sim}34.50^{\circ}C$) but R.H % was more ($55{\sim}81%$) in season-2. Fluctuations between minimum and maximum temperature and R.H % were more ($20.00{\sim}40.5^{\circ}C$ and $64.00{\sim}90.00%$) in season-3. Growth rate of microsporidian-infected silkworm is directly related to the prevailing temperature and relative humidity in silkworm. Silkworm can tolerate slight variation of temperature but slight variation of relative humidity disfavours the development of silkworm and favours the multiplication of pathogens.

백목련의 가지 생장 유형

  • 최형선
    • The Korean Journal of Ecology
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    • v.16 no.4
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    • pp.417-428
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    • 1993
  • Branching growth pattern of Mugnolza denuduta is likely to be originated from two growth strategies: environment overcoming strategy and life maintenance strategy, which coexist in a tree. Growth rate of branches was strongly correlated with relative light intensity (P<0.001) and physical contact (P<0.01), however there is no significant correlation between growth rate and direction of branch. When relative light intensity is less than 1%, the growth was restricted by physical contact with the surrounding branches. In contrast, the growth was rarely restricted by physical contact when relative light intensitiy was 10% or more. The branching rate was significantly affected by the presence or absence of physical contact (P<0.05), but it was not significantly affected by relative light intensity nor by the direction of branch. In the beginning stage of the growth, the ratio of the material allocation from main branch to subbranch was large and varied with the influence of surrounding environment. These various growth rates, which implicate a variety of material allocation ratios (0.16~0.98), affect branch growth pattern through the optimum growth strategies. The growth and arrangement of branches of Magnolia denudata display the solar collectors to maximize the total amount of energy absorbed and to overcome the restriction of the environment.

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Variations of Air Temperature, Relative Humidity and Pressure in a Low Pressure Chamber for Plant Growth (식물생장용 저압챔버 내의 기온, 상대습도 및 압력의 변화)

  • Park, Jong-Hyun;Kim, Yong-Hyeon
    • Journal of Bio-Environment Control
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    • v.18 no.3
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    • pp.200-207
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    • 2009
  • This study was conducted to analyze the variations of air temperature, relative humidity and pressure in a low pressure chamber for plant growth. The low pressure chamber was composed of an acrylic cylinder, a stainless plate, a mass flow controller, an elastomer pressure controller, a read-out-box, a vacuum pump, and sensors of air temperature, relative humidity, and pressure. The pressure leakage in the low pressure chamber was greatly affected by the material and connection method of tubes. The leakage rate in the low pressure chamber with the welding of the stainless tubes and a plate decreased by $0.21kPa{\cdot}h^{-1}$, whereas the leakage in the low pressure chamber with teflon tube and rubber O-ring was given by $1.03kPa{\cdot}h^{-1}$. Pressure in the low pressure chamber was sensitively fluctuated by the air temperature inside the chamber. An elastomer pressure controller was installed to keep the pressure in the low pressure chamber at a setting value. However, inside relative humidity at dark period increased to saturation level.. Two levels (25 and 50kPa) of pressure and two levels (500 and 1,000sccm) of mass flow rate were provided to investigate the effect of low pressure and mass flow rate on relative humidity inside the chamber. It was concluded that low setting value of pressure and high mass flow rate of mixed gas were the effective methods to control the pressure and to suppress the excessive rise of relative humidity inside the chamber.

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.

Growth Characteristic of Warm-season Turfgrass in Saemangeum Reclaimed Land (새만금간척지에서 난지형 잔디의 생육 특성)

  • Bae, Eun-Ji;Han, Jeong-Ji;Lee, Kwang-Soo;Park, Yong-Bae;Choi, Su-Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.1
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    • pp.13-23
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    • 2016
  • This study was conducted to investigate the growth characteristics of warm-season turfgrasses and to find out suitable turfgrass species on Saemangeum reclaimed land. Twenty native zoysiagrass(Zoysia sinica, Z. matrella, Z. japonica, Medium-leaf type zoysiagrass(hybrid zoysiagrass)) and bermudagrass(Cynodon dactylon) collected from Korea were used in this study. Total stolon length and the number of stolon per square meter, relative growth rate of shoot and stolon, and coverage rate were analyzed for 2 year. C. dactylon showed not only the most growth response with high relative growth rate of shoot and stolon, which were 19.9% and 66.3%, but also resulted in higher level of turf visual quality compared to others. Whereas Z. japonica showed the least growth response with low relative growth rate of shoot and stolon, which were 2.4% and 0.7%. Although all warm-season turfgrasses took root and grew up well, there were different growth rates between the interspecies. Z. sinica 'Z2034', Z. matrella 'Z4091', Z. japonica 'Z1064', Medium-leaf type zoysiagrass 'ZN6019' and C. dactylon 'BN7014' were the greatest growth rate of shoot and stolon. These results will be useful for selecting salt tolerant breeding lines and also used to develop a turfgrass cultivar with strong salinity tolerance through continuous monitoring.