Translocation of (14C) [carbon isotope]sucrose in wheat [Triticum aestivum]

Flag leaves of wheat plants (Triticum aestivum L. em. Thell. cv 'Duke') were supplied with 14C(glucosyl)sucrose. Translocated [14C]sucrose was isolated, then hydrolyzed. Label appeared in both the hexose moieties indicating that some randomization of label had occurred. However, near the radioactive front essentially all of the 14C was in the glucose moiety, suggesting that randomization occurred after unloading, supporting the conclusion that sucrose was taken up intact by phloem and translocated unaltered.