Severa1 different types of tests have indicated that the
TRIA/L(+)-adenosine action may be physical in nature. For
example, octacosanol applied to the shoots or roots of rice
seedlings inhibited the activity of TRIA applied to the oppo-site plant part, providing it was applied 1 min prior to TRIA
application (Ries and Wert, 1988). TRIA applied to oat (Avena
sativa L.) or tomato (Lycopersicon esculentum Mill.) shoots
connected to rice roots by a 4-mm water column also resulted
in the appearance of L(+)-adenosine (TRIM) in rice roots (Ries
and Wert, 1988).