Comparative Photosynthetic Properties of Palisade Tissue Chloroplasts and Spongy Tissue Chloroplasts ofCamellia japonicaL.: Functional Adjustment of the Photosynthetic Apparatus to Light Environment within a Leaf

摘要

The photochemical properties of chloroplasts isolated separately from palisade and spongy tissues ofCamellialeaves, were compared, and the following results were obtained: (1) The content of the light-harvesting Chia/b-protein complex was higher in spongy tissue chloroplasts (S-Chlts) than in palisade tissue chloroplasts (P-Chlts), while the contents of P700 and PS IT polypeptides were higher in P-Chlts. (2) Fluorescence induction was slower in P-Chlts, indicating that they had a larger plastoquinone pool than S-Chlts. (3) The quantum yield of PS II electron transport in S-Chlts was appreciably higher, while that of PS I electron transport was higher in P-Chlts. (4) The maximal rates of both PS I and PS IT electron transport under saturating light were higher in P-Chlts than in S-Chlts.From these results, we concluded that the photochemical properties in P-Chlts are adjusted to high light intensity and those of S-Chlts to low intensity enriched in green and far-red; both are adjusted to their respective in situ light environments.