Relative to the mode of action of exogenously applied
TRIA and L(+)-adenosine, it is postulated that both compounds
move rapidly through the leaf cuticle to the plasma
membrane of epidermal cells. TRIA then elicits the formation
of L(+)-adenosine. This study suggests that L(+)-adenosine
triggers a rapidly transmitted signal within whole plants that
results in a transient increase in apoplastic ion concentration
within stem tissue. These results are consistent with and offer
supportive evidence for the anomalous rapid responses of
plants to both TRIA and L(+)-adenosine (Ries, 1991).