( ( ( ( ( ( The ( rapid decrease ) ) ( in ( ( sucrose ( and ( TNC concentrations ) ) ) ( in ( roots ( in ( early summer ) ) ) ) ) ) ) , ) ( while ( ( ( carbohydrate concentrations ) ( in ( ( lignotubers and ) stems ) ) ) ( remained ( relatively constant ) ) ) ) ) , ) ( ( suggests ( that ( sugars ( were ( being ( consumed ( by ( ( ( the roots ) , ) ( which ( are ( ( the ( main ( cabohydrate sink ) ) ) ( of ( this plant ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ rapid) (NN decrease)) (PP (IN in) (NP (NP (NN sucrose) (CC and) (NN TNC) (NNS concentrations)) (PP (IN in) (NP (NP (NNS roots)) (PP (IN in) (NP (JJ early) (NN summer))))))) (, ,) (SBAR (IN while) (S (NP (NP (JJ carbohydrate) (NNS concentrations)) (PP (IN in) (NP (NNS lignotubers) (CC and) (NNS stems)))) (VP (VBD remained) (ADJP (RB relatively) (JJ constant))))) (, ,)) (VP (VBZ suggests) (SBAR (IN that) (S (NP (NNS sugars)) (VP (VBD were) (VP (VBG being) (VP (VBN consumed) (PP (IN by) (NP (NP (DT the) (NNS roots)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBP are) (NP (NP (DT the) (JJ main) (NN cabohydrate) (NN sink)) (PP (IN of) (NP (DT this) (NN plant))))))))))))))) (. .)))
The rapid decrease in sucrose and TNC concentrations in roots in early summer, while carbohydrate concentrations in lignotubers and stems remained relatively constant, suggests that sugars were being consumed by the roots, which are the main cabohydrate sink of this plant.
(ROOT (S (NP (NNS Plants)) (ADVP (RB generally)) (VP (VB transport) (NP (NNS carbohydrates)) (PP (IN from) (NP (NP (NP (NNS leaves)) (PP (TO to) (NP (NNS roots)))) (CC and) (NP (NP (JJ other) (JJ nonphotosynthetic) (NNS organs)) (PP (IN in) (NP (NP (DT the) (NN form)) (PP (IN of) (NP (NN sucrose))))))))) (. .)))