• Title/Summary/Keyword: early growth stage

Search Result 1,469, Processing Time 0.034 seconds

Assessment of Critical Temperature for the Growth and Development of Early Transplanted Temperate Rice

  • Wbonho Yang;Shingu Kang;Dae-Woo Lee;Jong-Seo Choi
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.171-171
    • /
    • 2022
  • Effect of temperature during the period of 10 days from transplanting (10 DFT) on the growth and development of rice plants was investigated by transplanting semi-adult seedlings six times from 5 April to 15 May at 10-day interval in the field conditions of 2020 and 2021, with aims to investigate the critical temperature for early transplanting of temperate rice. In the two experimental years, mean temperature for 10 DFT appeared 9.1, 10.5, 11.6, 13.8, 13.9, 16.2, 16.4, 16.7, 17.1, 17.8℃ depending on the transplanting date. Mean temperature of 9.1℃ and 10.5℃ for 10 DFT appeared in the April 5 and April 15 transplants in 2020 showed negative or no effect on the increase of rice growth and acceleration of heading date when compared to those of right after transplanting treatments in the same year. Mean temperature of 11.6℃ for 10 DFT appeared in the April 5 transplant in 2021 demonstrated greater biomass from early to heading stage but the same heading date compared to April 15 transplant, indicating that 11.6℃ for 10 DFT had a positive effect on rice growth but no effect on advanced heading. Both more biomass and advanced heading stage were observed when the mean temperature for 10 DFT was 13.8℃ or higher, compared to those of right after transplanting treatments. These findings indicate that effective 10-DFT mean temperature for rice growth exists between 10.5 and 11.6℃, and that for rice development in terms of heading stage lies between 11.6 and 13.8℃ in natural condition. Further field and indoor studies are suggested to narrow down the critical temperature for early transplanting of temperate rice, which will enable to maximize the crop period in high altitude regions with low temperature.

  • PDF

Effects of a pineapple (Ananas comosus L.) cannery by-product on growth performance and carcass characteristics in finishing Hanwoo steers

  • Choi, Yongjun;Lee, Sangrak;Na, Youngjun
    • Animal Bioscience
    • /
    • v.34 no.2
    • /
    • pp.233-242
    • /
    • 2021
  • Objective: The aim of this study was to determine the effect of pineapple cannery by-product (PCB) level on the growth performance and carcass characteristics of finishing Hanwoo steers. Methods: The feeding stage was divided into early and late finishing stages. A total of 60 castrated Hanwoo steers (13.9±0.8 months old, 418.8±36.5 kg initial body weight [BW]) were blocked by initial BW and then randomly allotted into 12 pens (five head/pen). The pens were randomly assigned to control (CONT), low PCB (LPCB), or high PCB (HPCB) treatments. These diets contained 0%, 1.5%, or 3.0% of PCB (on a dry matter [DM] basis; as-fed basis was 0%, 10.6%, or 21.2%), respectively. Results: For the early finishing stage, body weight gain (BWG) and average daily gain (ADG) of the CONT and LPCB feeding groups were greater (p<0.05) than those of the HPCB feeding group. In addition, there were linear and quadratic effects on BWG and ADG with increasing dietary PCB level (p<0.05). The gain to feed (G:F) ratio tends to quadratically decrease with an increasing PCB level in the early finishing stage (p = 0.076). Growth performances of late finishing stage were not affected by PCB level. The marbling score of the LPCB feeding group was similar to that of the CONT feeding group. However, there was a linear decrease (p< 0.05) in marbling score and quality grade among treatments as PCB was increased in the diet. In the longissimus muscle free amino acid profile, histidine composition increased linearly (p<0.05) with an increasing level of PCB. Conclusion: The level of PCB 1.5% DM in diet can be used for finishing steers without any adverse effects on growth and carcass performances. However, there were some negative effects on growth and carcass performance in the HPCB feeding group.

A Study on the Shot Peening on the High Temperature Fatigue Crack Propagation (쇼트피이닝 가공된 스프링강의 고온 피로균열진전 평가)

  • 박경동;정찬기;하경준
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 2001.10a
    • /
    • pp.264-268
    • /
    • 2001
  • In this study, CT specimens were prepared from spring steel(SUP9) processed shot peening which was room temperature, low temperature and high temperature experiment. And we got the following characteristics from fatigue crack growth test carried out in the environment of room, and high temperature at $25^{\circ}C,\; 50^{\circ}C, \;100^{\circ}C,\; 150^{\circ}C,\; and\; 180^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range $\DeltaK_{th}$ in the early stage of fatigue crack growth (Region I ) and stress intensity factor range $\Delta$K in the stable of fatigue crack growth (Region II) was decreased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

  • PDF

A Study on the Fatigue Crack Propagation Characteristics for SUP9 Steel at Low Temperature (SUP9강의 저온피로크랙 전파특성에 관한 연구)

  • 박경동;박상오
    • Journal of Ocean Engineering and Technology
    • /
    • v.16 no.5
    • /
    • pp.80-87
    • /
    • 2002
  • In this study, CT specimens were prepared from spring steel(SUP9) which was used in suspension of automobile for room temperature and low temperature service. We got the following characteristics from fatigue crack growth test carried out in the environment of room temperature and low temperature at $25^{\circ}C$, ­3$0^{\circ}C$, ­5$0^{\circ}C$, ­7$0^{\circ}C$ and ­10$0^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range ΔK in the stable of fatigue crack growth (Region II) was decreased in proportion to descend temperature. It is assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

An Effect of Temperature on the Fatigue Crack Propagation Behavior of Spring Steel for Vehicle (차량용 스프링강의 피로거동에 미치는 온도의 영향)

  • 박경동;류찬욱
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.12 no.1
    • /
    • pp.83-90
    • /
    • 2004
  • In this study, CT specimens were prepared from spring steel(SUP9) processed shot peening which was room temperature and low temperature experiment. And we got the following characteristics from fatigue crack growth test carried out in the environment of room temperature and low temperature at $25^{\circ}C$, $-30^{\circ}C$, $-50^{\circ}C$, $-70^{\circ}C$,$-100^{\circ}C$, and $-150^{\circ}C$, in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I)was increased but stress intensity factor range ΔK in the stable of fatigue crack growth (Region II) was decreased in proportion to decrease temperature. It is assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerably higher than that of room temperature in the early stage and stable of fatigue crack growth region.

An Evaluation on the Fatigue Strength Characteristics for the Shot Peening Spring Steel at Low Temperature (숏피닝 가공재의 저온 피로 강도 평가)

  • 박경동;권오헌
    • Journal of the Korean Society of Safety
    • /
    • v.18 no.3
    • /
    • pp.1-7
    • /
    • 2003
  • In this study, CT specimens were prepared from spring steel(SPS5) processed shot peening. The fatigue crack growth tests were carried out in the environment of the room temperature md low temperature at $25^{\circ}C$, $-30^{\circ}C$, $-50^{\circ}C$, $-70^{\circ}C$ $-100^{\circ}C$ and $-150^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\Delta$K in the stable of fatigue crack growth (Region II) were decreased in proportion to descend temperature. It was shown that the fatigue resistance characteristics and fracture strength at low temperature are considerable higher than those of mom temperature in the early stage and stable of fatigue crack growth region.

Managing Information Asymmetry Risks Using Deal Syndication and Domain Specialization: An Indian Context

  • Joshi, Kshitija
    • Asian Journal of Innovation and Policy
    • /
    • v.7 no.1
    • /
    • pp.150-177
    • /
    • 2018
  • We review two specific risk management strategies of venture capitalists (VCs): deal syndication and domain specialization with respect to their explicit role in adjudging and managing the overall magnitude of information asymmetry risks. These are analyzed for three distinct categories of VC firms as classified by their funding stage focus (early vs. late), ownership type (foreign vs. domestic) and the human capital composition of the core VC team (entrepreneurial vs. investor). The analysis is based on both secondary data and primary data for active 72 VC firms in India. Syndication is moderately important for entrepreneurial VC firms, but not at all important for early-stage focused and foreign VC firms. This finding is distinctly different from what has been conventionally observed in the literature. Among the various arenas of domain specialization, high-technology focus is important for all segments of VC firms. In the context of investment-stage focus, foreign VC firms exhibit growth-stage specialization, while entrepreneurial VC firms concentrate on earlier investment stages.

Formation of Sensory Pigment Cells Requires Fibroblast Growth Factor Signaling during Ascidian Embryonic Development

  • Kim, Gil-Jung
    • Animal cells and systems
    • /
    • v.7 no.3
    • /
    • pp.221-225
    • /
    • 2003
  • The tadpole larva of the ascidian Halocynthia roretzi has two sensory pigment cells in its brain vesicle. To elucidate the temporal requirement for FGF signaling in formation of the pigment cells, embryos were treated with an FGF receptor 1 inhibitor, SU5402, or an MEK inhibitor, U0126 during various embryonic stages. In the present study, it is shown that the embryos treated with SU5402 from the 16-cell stage to the early gastrula stage do not form pigment cells, whereas those treated after the early gastrula stage form pigment cells. In pigment cell formation, embryos suddenly exhibited the sensitivity to SU5402 only for 1 h at the neural plate stage(-4 h after the beginning of gastrulation). When U0126 treatment was carried out at various stages between the 8-cell and late neurula stages, the embryos scarcely formed pigment cells. Pigment cell formation occurred when the embryos were placed in U0126 at early tail bud stage. These results indicate that FGF signaling is involved in pigment cell formation at two separate processes during ascidian embryogenesis, whereas more prolonged period is required for MEK signaling.

Effect of Cyclosulfamuron on Rice Growth and Acetolactate Synthase Activity (Cyclosulfamuron이 벼의 생육과 Acetolactate Synthase 활성에 미치는 영향)

  • Ji, Seung-Hwan;Song, Sung-Do;Jeong, Byeong-Ryong
    • Korean Journal of Environmental Agriculture
    • /
    • v.22 no.1
    • /
    • pp.36-40
    • /
    • 2003
  • Cyclosulfamuron a herbicide of sulfonylurea type, is a relatively new compound which control broad leaves and perennial weeds in rice field. However, this herbicide has a minor disadvantage of decreasing rice plant growth, especially in early growth stage. Therefore, far introducing this cyclosulfamuron as a herbicide in rice field, it is important to minimize the suppression of early plant growth with maintaining weed control efficacy. This study was conducted to evaluate effects of cyclosulfamuron early plant growth and acetolactate synthase activity of rice (Oryza sativa cv Dongjinbyeo, Hwasungbyeo, Ilpumbyeo). Rice growth was inhibited by cyclosulfamuron in their early growth stage. The concentrations required far 50% inhibition of Dongjinbyeo, Hwasungbyeo and Ilpumbyeo growth were 6.3, 9.2 and 146.mg/kg, respectively. Inhibition effect of cyclosulfamuron on the root elongation was greater than the effect on the shoot growth. Concentrations required far 50% inhibition of acetolactate synthase activity from Dongjinbyeo, Hwasungbyeo, Ilpumbyeo were 42.7, 32.7 and $56.7\;{\mu}M$, respectively.

Growth and Yield of Rice as Affected by Saline Water Treatment at Different Growth Stages (벼 생육시기별 염수처리 농도와 기간에 따른 생육 및 수량)

  • 이충근;윤영환;신진철;이변우;김정곤
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.47 no.6
    • /
    • pp.402-408
    • /
    • 2002
  • Rice cultivar 'Janganbyeo' was cultivated by irrigating the saline waters of high salinity (3.0%) and medium saliniy (1.5%) for 4 days, and low salinity (0.5%) for 30 days at tillering, early meiosis and heading stage. Leaf injury due to salinity was most severe at tillering stage in 1999, but at heading stage in 2000. Heading date was delayed by 1 to 5 days by treatment of saline waters only at tillering stage. Culm length and panicle length were most severely shortened by treatment at early meiosis stage. Yield and yield components except for panicle number were decreased most by high salinity treatment regardless of growth stages. In particular, ripening ratio and grain weight among the yield components were decreased most conspicuously by the saline water treatment regardless of salinity and growth stage. Regarding grain weight grain-filling rate and duration, there is no remarked difference among the concentrations and treatment durations of saline water at tillering stage. However, their reductions were very different among the concentrations and treatment durations of saline water at early meiosis stage, being greatest when treated with high salinity for 4 days and followed by low salinity for 30 days. Also their reductions were very severe only when treated with high salinity for 4 days at heading stage.