Effects of clinorotation and calcium channel blockers on calcium balance in graviperceptive cells of pea roots.

摘要

Pea cv. Uladovskii seeds were germinated on filter paper in glass tubes kept vertical or rotated on the horizontal axis of a clinostat for 5 days at 2 r.p.m.; 12 h before rotation ceased 1鍹 solutions of the Ca2+ channel blockers D600 or nicardipinewere injected into the growth medium. Conditions in space flight and clinorotation had previously been shown to increase Ca2+ concentration in root statocytes. The combination of rotation and Ca2+ channel blockers reduced Ca2+ concentration in the statocytes. The localization of Ca2+ and Ca2+-ATPase activity in the statocytes of control and treated plants is described. After application of D600 the distribution of Ca2+-ATPase activity was similar to that in the control, but after nicardipine application it was intermediate between that of the stationary control and that of rotated roots. The role of Ca2+ channels in perception of gravitational stimuli and microgravity effects, and ways of stabilizing plant Ca2+ balance under space flight conditions are discussed.