RT Journal Article SR Electronic T1 Effects of Lanthanum and Ethylenediaminetetraacetate on Leaf Movements of Mimosa JF Plant Physiology JO Plant Physiol. FD American Society of Plant Biologists SP 635 OP 639 DO 10.1104/pp.60.4.635 VO 60 IS 4 A1 Campbell, Neil A. A1 Thomson, William W. YR 1977 UL http://www.plantphysiol.org/content/60/4/635.abstract AB Lanthanum and ethylenediaminetetraacetate (EDTA) profoundly affect the rapid leaf movements of Mimosa pudica L. Lanthanum, which mimics calcium but does not penetrate the plasmalemma, inhibits the closing response but does not affect reopening. A low concentration of EDTA retards the reopening process while a higher EDTA concentration prevents the closing movement. There is evidence that the EDTA effects result from chelation of calcium ions rather than chelation of other cations. These results are discussed with regard to the role of calcium in leaf movements.