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    • Journal of Range Management, Volume 45 (1992)
    • Journal of Range Management, Volume 45, Number 1 (January 1992)
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    Germination responses of Lehmann lovegrass to light

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    Author
    Roundy, B. A.
    Taylorson, R. B.
    Sumrall, L. B.
    Issue Date
    1992-01-01
    Keywords
    red light
    far-red light
    phytochrome
    seedbed ecology
    mowing
    burning
    light relations
    soil temperature
    light
    seedling emergence
    fires
    fire effects
    seed germination
    Eragrostis lehmanniana
    pasture plants
    grazing
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    Citation
    Roundy, B. A., Taylorson, R. B., & Sumrall, L. B. (1992). Germination responses of Lehmann lovegrass to light. Journal of Range Management, 45(1), 81-84.
    Publisher
    Society for Range Management
    Journal
    Journal of Range Management
    URI
    http://hdl.handle.net/10150/644719
    DOI
    10.2307/4002531
    Additional Links
    https://rangelands.org/
    Abstract
    Lebmann lovegrass (Eragrostis lehmanniana Nees.) is a perennial, warm-season bunchgrass that is native to South Africa and has been seeded and spread naturally in the southwestern United States. Germination of 4 seed lots of varying age was tested in relation to darkness and irradiance with red (R) and far-red (FR) light. Germination was low in continual darkness, but greatly increased after exposure to R. Irradiation with FR after exposure to R reduced germination, confirming phytochrome involvement. Exposure to R after prolonged imbibition in FR did not increase germination of 1-2-year-old seeds and only slightly increased germination of older seeds. An alternating temperature of 16 hours at 15 degrees C and 8 hours at 38 degrees C greatly increased germination of seeds exposed to fluorescent light and slightly increased germination of seeds in darkness compared to a constant temperature of 25 degrees C. Greater seedling emergence of Lehmann lovegrass when the canopy is opened by burning, mowing, or grazing is likely a function of red light stimulation of biologically active phytochrome and increased seedbed temperature fluctuations.
    Type
    text
    Article
    Language
    en
    ISSN
    0022-409X
    ae974a485f413a2113503eed53cd6c53
    10.2307/4002531
    Scopus Count
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    Journal of Range Management, Volume 45, Number 1 (January 1992)

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