Open AccessMovement of Abscisic Acid into the Apoplast in Response to Water Stress in Xanthium strumarium L.
Author(s) -
Katrina Cornish,
Jan A. D. Zeevaart
Publication year - 1985
Publication title -
plant physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.554
H-Index - 312
eISSN - 1532-2548
pISSN - 0032-0889
DOI - 10.1104/pp.78.3.623
Subject(s) - apoplast , abscisic acid , turgor pressure , xylem , wilting , symplast , guard cell , transpiration , dehydration , water stress , chemistry , xanthium , botany , horticulture , biology , photosynthesis , cell wall , biochemistry , gene
The effect of water stress on the redistribution of abcisic acid (ABA) in mature leaves of Xanthium strumarium L. was investigated using a pressure dehydration technique. In both turgid and stressed leaves, the ABA in the xylem exudate, the ;apoplastic' ABA, increased before ;bulk leaf' stress-induced ABA accumulation began. In the initially turgid leaves, the ABA level remained constant in both the apoplast and the leaf as a whole until wilting symptoms appeared. Following turgor loss, sufficient quantities of ABA moved into the apoplast to stimulate stomatal closure. Thus, the initial increase of apoplastic ABA may be relevant to the rapid stomatal closure seen in stressed leaves before their bulk leaf ABA levels rise.Following recovery from water stress, elevated levels of ABA remained in the apoplast after the bulk leaf contents had returned to their prestress values. This apoplastic ABA may retard stomatal reopening during the initial recovery period.