Effects of Ethylene and Carbon Dioxide on the Germination of Osmotically Inhibited Lettuce Seed
Year: 1978
Type: article
Abstract: Lettuce seeds (Lactuca sativa L.) used in this study germinated 98% at 25 C in light or dark. Their germination was completely inhibited by 0.20 m NaCl, 0.35 m mannitol, or polyethylene glycol 6000 (-7 bars) under continuous light when germination tests were made in Petri dishes. Approximately 50% germination occurred in sealed flasks due to endogenously produced C(2)H(4) and CO(2). Removal of either or both gases prevented germination. In the presence of endogenous CO(2), addition of C(2)H(4) (0.5 to 16 microliters/liter) stimulated 95 to 100% germination (after 5 days) only in the light, but the rate of germination was dependent on C(2)H(4) concentration. At 16 microliters/liter C(2)H(4), full germination occurred within 72 hours. Addition of up to 3.2% CO(2) had no adverse effect on the C(2)H(4) action. Higher concentrations or the complete absence of CO(2) reduced both rate and total germination. CO(2) alone was ineffective.Under these osmotic conditions the promotive effect of C(2)H(4) was under the control of phytochrome.
Source: PLANT PHYSIOLOGY
DOI: 10.1104/pp.62.4.473
Authors: Fayek B. Negm, Orrin E. Smith
Institution: Washington State University
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W2093476410