Influence of ethanol and ethylene on the seed germination of three nymphaeid water plants

• Published in: Freshwater biology 1995-08, Vol.34 (1), p.39-46
• Main Authors: SMITS, A.J.M., SCHMITZ, G.H.W., VAN DER VELDE, G., VOESENEK, L.A.C.J.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Autoecology; Biological and medical sciences; Freshwater; Fundamental and applied biological sciences. Psychology; Nuphar lutea; Nymphaea alba; Nymphoides peltata; Plants and fungi
• ISSN: 0046-5070; 1365-2427
• DOI: 10.1111/j.1365-2427.1995.tb00421.x

SUMMARY 1. Under anaerobic conditions cold stratified seeds of Nymphaea alba and Nuphar lutea germinated readily and released ethanol (up to 6–7 mM ethanol g‐1 DW), whereas seeds of Nymphoides peltata did not germinate and hardly any ethanol was released (up to 1.5 mM ethanol g‐1 DW). Ethylene release by seeds of Nymphaea, Nuphar and Nymphoides incubated under hypoxic conditions could not be detected. 2. Under aerobic conditions all Nymphaea and Nuphar seeds germinated, but at a lower rate compared with anaerobic incubation. Ethanol release under aerobic conditions was low (1.5–2 mM ethanol g‐1 DW). Under aerobic conditions the seeds of Nymphoides germinated promptly and ethanol release was low (0–0.5 mM ethanol g‐1 DW). 3. Germination of Nymphaea and Nuphar seeds in an ethanol solution (350 mM) was generally stimulated compared with that in water, but no significant effect was recorded if seeds had not received a cold treatment or had been stratified for 8 weeks. Germination of Nymphoides seeds was inhibited in the ethanol solution unless they had received a cold treatment of 12 weeks. 4. Germination of Nymphaea and Nuphar was stimulated by ethylene (5 νg 1‐1) but germination in moist air was lower than under normal submersed conditions. A stimulating effect of ethylene on the germination of Nymphoides seeds was also evident. 5. It is suggested that ethanol and ethylene play an important role in determining niches for germination, contributing to the zonation of these nymphaeids in a water body.