Ascophyllum nodosum extracts contain various betaines
and betaine-like compounds (Blunden and others 1986). In
plants, betaines serve as a compatible solute that alleviates
osmotic stress induced by salinity and drought stress;
however, other roles have also been suggested (Blunden
and Gordon 1986), such as enhancing leaf chlorophyll
content of plants following their treatment with seaweed
extracts (Blunden and others 1997). This increase in
chlorophyll content may be due to a decrease in chlorophyll
degradation (Whapham and others 1993). Yield
enhancement effects due to improved chlorophyll content
in leaves of various crop plants have been attributed to the
betaines present in the seaweed (Genard and others 1991;
Whapham and others