title: The major growth current through lily pollen tubes enters as K(+) and leaves as H (+).
abstract: Growing lily (Lilium longiflorum Thunb.) pollen always drive a current into their tubes and out of their grains. The only external ions needed for growth (and the growth current) are K(+), H(+), and Ca(2+). Increases in K(+) immediately stimulate the current; while decreases in K(+) immediately inhibit it. Comparable changes in H(+) have the opposite effect; while those in Ca(2+) have very little effect. We infer that most of the steady growth current is carried in by a potassium leak and out by a proton pump; but other considerations indicate that a minor, but controlling, component of the inward current consists of calcium ions.
authors.affiliation: Biology Department, Purdue University, 47907, Lafayette, IN, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Weisenseel
authors.forename: L F
authors.initials: LF
authors.lastname: Jaffe