PT - JOURNAL ARTICLE AU - Campbell, Neil A. AU - Thomson, William W. TI - Effects of Lanthanum and Ethylenediaminetetraacetate on Leaf Movements of <em>Mimosa</em> AID - 10.1104/pp.60.4.635 DP - 1977 Oct 01 TA - Plant Physiology PG - 635--639 VI - 60 IP - 4 4099 - http://www.plantphysiol.org/content/60/4/635.short 4100 - http://www.plantphysiol.org/content/60/4/635.full SO - Plant Physiol.1977 Oct 01; 60 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.