( ( Our work ) ( ( has ( demonstrated ( that ( ( ( the ( major causes ) ) ( of ( ( this type ) ( of ( leaf yellowing ) ) ) ) ) ( are ( stresses ( that ( ( reduce ( ( ( both ( plant ( carbohydrate ( and ( gibberellin level ) ) ) ) ) , ) ( including ( ( ( growth ( regulator drenches ) ) , ) ( large ( negative DIF ) ) ) ) ) ) ( 's ( in ( ( ( ( ( the greenhouse ) , ) ( ( long ( cold storage ) ) ( of ( budded plants ) ) ) ) and ) ( ( lengthy ( , ( ( warm and ) dark ) ) ) shipping ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP$ Our) (NN work)) (VP (VBZ has) (VP (VBN demonstrated) (SBAR (IN that) (S (NP (NP (DT the) (JJ major) (NNS causes)) (PP (IN of) (NP (NP (DT this) (NN type)) (PP (IN of) (NP (NN leaf) (NN yellowing)))))) (VP (VBP are) (VP (VBG stresses) (SBAR (IN that) (S (S (VP (VB reduce) (NP (NP (DT both) (NN plant) (NN carbohydrate) (CC and) (NN gibberellin) (NN level)) (, ,) (PP (VBG including) (NP (NP (NN growth) (NN regulator) (NNS drenches)) (, ,) (NP (JJ large) (JJ negative) (NN DIF))))))) (VP (VBZ 's) (PP (IN in) (NP (NP (DT the) (NN greenhouse)) (, ,) (NP (NP (JJ long) (JJ cold) (NN storage)) (PP (IN of) (NP (JJ budded) (NNS plants)))) (CC and) (NP (ADJP (JJ lengthy) (, ,) (JJ warm) (CC and) (JJ dark)) (NN shipping))))))))))))) (. .)))
Our work has demonstrated that the major causes of this type of leaf yellowing are stresses that reduce both plant carbohydrate and gibberellin level, including growth regulator drenches, large negative DIF's in the greenhouse, long cold storage of budded plants and lengthy, warm and dark shipping.
(ROOT (S (NP (JJ Young) (NNS roots) (CC and) (NNS leaves)) (VP (VBP are) (NP (NP (DT the) (JJ major) (NNS sites)) (PP (IN of) (NP (NN gibberellin) (NN production))))) (. .)))