Issue Date
1992-01-01Keywords
red lightfar-red light
phytochrome
seedbed ecology
mowing
burning
light relations
soil temperature
light
seedling emergence
fires
fire effects
seed germination
Eragrostis lehmanniana
pasture plants
grazing
Metadata
Show full item recordCitation
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 ManagementJournal
Journal of Range ManagementDOI
10.2307/4002531Additional 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
textArticle
Language
enISSN
0022-409Xae974a485f413a2113503eed53cd6c53
10.2307/4002531
Scopus Count
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