Germination responses of Lehmann lovegrass to light
Issue Date
1992-01-01Keywords
red lightfar-red light
phytochrome
seedbed ecology
mowing
burning
light relations
soil temperature
light
seedling emergencefiresfire effectsseed germinationEragrostis lehmannianapasture plantsgrazing
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
0022-409XScopus Count
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