In conclusion, the changes in pigment content and photosynthetic
activity of flag leaf appeared to depend mainly on
chloroplast ultrastructure and its numbers, showing a positive
correlation between chloroplasts number and pigment content.
Application of exogenous kinetin, Spermine or their
interaction increased leaf expansion and pigment content as
well as improved the photosynthetic capacity of the seawater
stressed wheat plants. Furthermore, the positive effect of Spm
on photosynthesis might be involved in exogenous Spm
regulating endogenous polyamines as well as the physiological
effects of exogenous Spm on the structure and function of
chloroplast. The applied kinetin or spermine and their interaction
on ultrastructural characteristics of wheat flag leaves
are reflected on enhancing overall growth and productivity of
wheat plants as indicated by noticeable accumulation of
photosynthetic pigments as well as photosynthetic activity of
flag leaf at ear emergence.