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Author Taylor, G.; Davies, W.J. url  doi
openurl 
  Title (down) The Control Of Leaf Growth Of Betula And Acer By Photoenvironment Type Journal Article
  Year 1985 Publication New Phytologist Abbreviated Journal New Phytol  
  Volume 101 Issue 2 Pages 259-268  
  Keywords Plants  
  Abstract Leaf extension of one‐year‐old seedlings of silver birch (Betula pendula Roth.) and sycamore (Acer pseudoplatanus L.), was measured using linear variable transducers (LVDTs) interfaced to a microcomputer. Birch and sycamore seedlings exhibited contrasting patterns of leaf extension during a diurnal cycle with a 16 h photoperiod. Birch leaves grew more rapidly when illuminated; growth during the photoperiod was approximately doubled when compared with growth in the dark. Mean relative growth rates ±SE at ‘lights‐on + 3 h’ and ‘lights‐off + 5 h’ were 0.0136 ± 0.0016 and 0.0066 ± 0.0005 h−1 respectively. In direct contrast, growth of sycamore leaves was increased when leaves were darkened; mean relative growth rates + SE at ‘lights‐on+3 h’ and ‘lights‐off + 5 h’ were 0.0056 ± 0.0005 and 0.0094 ± 0.0008 h‐1 respectively.

When leaves of birch and sycamore were darkened, increased leaf turgor was measured in both species, but only in sycamore was this higher night‐time turgor associated with a higher rate of leaf growth.

Cell wall extensibility (WEX), an indication of the ability of cell walls to loosen and extend irreversibly, and cell surface pH were assessed in darkened and illuminated leaves of both species. An increase in WEX was measured when birch leaves were illuminated (P≤ 0.001) and this was accompanied by a decline in cell surface pH (P≤ 0.001). However, when leaves of sycamore were illuminated, WEX declined (P≤ 005) and cell surface pH increased (P≤ 0.001).

The ability of these species to survive beneath a woodland canopy is discussed in relation to the cellular factors controlling their leaf growth.
 
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  Series Volume Series Issue Edition  
  ISSN 0028-646X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 1992  
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Author Joo, Y.; Fragoso, V.; Yon, F.; Baldwin, I.T.; Kim, S.-G. url  doi
openurl 
  Title (down) The circadian clock component, LHY, tells a plant when to respond photosynthetically to light in nature Type Journal Article
  Year 2017 Publication Journal of Integrative Plant Biology Abbreviated Journal J Integr Plant Biol  
  Volume 59 Issue 8 Pages 572-587  
  Keywords plants  
  Abstract The circadian clock is known to increase plant growth and fitness, and thought to prepare plants for photosynthesis at dawn and dusk; whether this happens in nature was unknown. We transformed the native tobacco, Nicotiana attenuata to silence two core clock components, NaLHY (irLHY) and NaTOC1 (irTOC1). We characterized growth and light-and dark-adapted photosynthetic rates (Ac ) throughout a 24 h day in empty vector-transformed (EV), irLHY, and irTOC1 plants in the field, and in NaPhyA-and NaPhyB1-silenced plants in the glasshouse. The growth rates of irLHY plants were lower than those of EV plants in the field. While irLHY plants reduced Ac earlier at dusk, no differences between irLHY and EV plants were observed at dawn in the field. irLHY, but not EV plants, responded to light in the night by rapidly increasing Ac . Under controlled conditions, EV plants rapidly increased Ac in the day compared to dark-adapted plants at night; irLHY plants lost these time-dependent responses. The role of NaLHY in gating photosynthesis is independent of the light-dependent reactions and red light perceived by NaPhyA, but not NaPhyB1. In summary, the circadian clock allows plants not to respond photosynthetically to light at night by anticipating and gating red light-mediated in native tobacco.  
  Address Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knoll-Str. 8, D-07745, Jena, Germany  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1672-9072 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:28429400 Approved no  
  Call Number LoNNe @ kyba @ Serial 1657  
Permanent link to this record
 

 
Author Chang, C., Chang, K., & Fu, W. url  doi
openurl 
  Title (down) Testing of Various Monochromatic LED Lights Used in Supplemental Irradiation of Lettuce in Modern urban Rooftop Polytunnels Type Journal Article
  Year 2019 Publication Applied Engineering in Agriculture Abbreviated Journal  
  Volume Issue Pages  
  Keywords Plants  
  Abstract Urban farming could provide both vegetable growers and urban dwellers in general with more direct access to various fresh vegetables. Nevertheless, certain challenging problems associated with urban farming, including a lack of cultivation space and the effects of urban heat islands, must still be solved. Relatedly, a grower must, in some cases, also know how to utilize various forms of technology, such as lighting systems, as well as factors such as water availability. In this study, an original rooftop polytunnel design for lettuce (Lactuca sativa cv. Lollo Rosso) cultivation equipped with a hydroponic system and light emitting diodes (LEDs) is proposed. Various monochromatic lights were also tested for their effects on different quality parameters of lettuce. Specifically, supplemental red (655 nm), blue (445 nm), green (520 nm), and ultraviolet (380 nm) LED lights were used at night to apply photon fluxes of 150, 150, 150, and 20 μmol.m-2.s-1, respectively. The resulting effects of these different colored LEDs on the pigment concentration and growth response of the lettuce grown inside the roof polytunnel were then investigated. The experiment was then repeated several times with different environmental parameters in order to compare the effects of the different light wavelengths under higher temperatures and higher natural irradiation conditions.The results indicated that supplemental red or blue light at night could be strategically employed to maintain low nitrate levels and enhance the nutritional value and growth of lettuce grown in roof polytunnels.  
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  Notes Approved no  
  Call Number IDA @ intern @ Serial 2349  
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Author Ebisawa, M.; Shoji, K.; Kato, M.; Shimomura, K.; Goto, F.; Yoshihara, T. url  doi
openurl 
  Title (down) Supplementary Ultraviolet Radiation B Together with Blue Light at Night Increased Quercetin Content and Flavonol Synthase Gene Expression in Leaf Lettuce (Lactuca sativa L.) Type Journal Article
  Year 2008 Publication Environment Control in Biology Abbreviated Journal Environ. Control Biol.  
  Volume 46 Issue 1 Pages 1-11  
  Keywords Plants  
  Abstract Establishment of an effective supplementary lighting procedure is necessary to increase the value of leaf lettuce grown using a hydroponic method involving a low production cost. In leaf lettuce extracts, quercetin, one of the flavonoids, was isolated and identified. It was investigated that quercetin has important functions that can be used as a dietary supplement. Flavonol synthase (FLS) is a key enzyme involved in quercetin biosynthesis, catalyzes the conversion of dihydroquercetin to quercetin. Therefore, we determined the sequence of the flavonol synthase gene (FLS) in red leaf lettuce. We harvested leaf lettuce grown using supplementary light sources, such as ultraviolet radiation B (UV-B), ultraviolet radiation A, blue, and red lamps during the night. It is noteworthy that FLS expression and the quercetin content were particularly increased to a greater extent in young leaves than in mature leaves when UV-B and blue light were used simultaneously at night. We suggest that UV-B with blue light is used simultaneously at night for producing leaf lettuce with high quercetin content.  
  Address  
  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1880-554X ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number GFZ @ kyba @ Serial 2799  
Permanent link to this record
 

 
Author Bian, Z.; Yang, Q.; Li, T.; Cheng, R.; Barnett, Y.; Lu, C. url  doi
openurl 
  Title (down) Study of the beneficial effects of green light on lettuce grown under short-term continuous red and blue light-emitting diodes Type Journal Article
  Year 2018 Publication Physiologia Plantarum Abbreviated Journal Physiol Plant  
  Volume 164 Issue 2 Pages 226-240  
  Keywords Plants  
  Abstract Red and blue light are the most important light spectra for driving photosynthesis to produce adequate crop yield. It is also believed that green light may contribute to adaptations to growth. However, the effects of green light, which can trigger specific and necessary responses of plant growth, have been underestimated in the past. In this study, lettuce (Lactuca sativa L.) was exposed to different continuous light (CL) conditions for 48 h by a combination of red and blue light-emitting diodes (LEDs) supplemented with or without green LEDs, in an environmental-controlled growth chamber. Green light supplementation enhanced photosynthetic capacity by increasing net photosynthetic rates (Pn ), maximal photochemical efficiency (Fv /Fm ), electron transport for carbon fixation (JPSII ) and chlorophyll content in plants under the CL treatment. Green light decreased malondialdehyde and H2 O2 accumulation by increasing the activities of superoxide dismutase (SOD; EC 1.15.1.1) and ascorbate peroxidase (APX; EC 1.11.1.11) after 24 h of CL. Supplemental green light significantly increased the expression of photosynthetic genes LHCb and PsbA from 6 to 12 h, and these gene expression were maintained at higher levels than those under other light conditions between 12 and 24 h. However, a notable down-regulation of both LHCb and PsbA was observed during 24 to 48 h. These results indicate that the effects of green light on lettuce plant growth, via enhancing activity of particular components of antioxidantive enzyme system and promoting of LHCb and PsbA expression to maintain higher photosynthetic capacity, alleviated a number of the negative effects caused by CL.  
  Address School of Animal, Rural and Environmental Science, Brackenhurst Campus, Nottingham Trent University, NG25 0QF, UK  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9317 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:29493775 Approved no  
  Call Number GFZ @ kyba @ Serial 1905  
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