Abstract:Electron microscopic observation indicated that the mitochondrial membrane of pea cotyledon gradually developed into integral structure during seeds imbibition. ATP-synthesizing activity of H+-ATPase increased in company with mitochondrial development, but the content of F1-ATPase subunits was not different on the mitochondria of cotyledon imbibed for 6 hours and for 24 hours in water. After cotyledon was imbibed at low temperature, the content of γ and β subunits of F1-ATPase was distinctly reduced with the inhibition of H+-ATPase activity.