The Importance of Blue Light for the Development of Sun-Type Chloroplasts

Abstract

Depending on environmental factors, the development of chloroplasts from either pro-plastids or etioplasts will lead to two distinctive types of chloroplast, which are different in composition, ultrastructure, and photosynthetic activity [1, 8]. At low light intensities and in shade leaves the shade-type chloroplast with high grana stacks, lower Hill activity rates and a higher level of chlorophyll b is formed, indicating more light-harvesting complex CPII [6, 10]. Sun leaves and plants grown at high light intensities, in turn, develop sun-type chloroplasts with less lamellar material and only few and low grana stacks. Their higher Hill activity is correlated with a higher level of prenylquinones, which function as potential photosynthetic electron carriers, and can also be seen in a changed chlorophyll (higher a/b ratios) and carotenoid composition (lower x/c ratios) [6].