作者: Z. A. Huang , D. A. Jiang , Y. Yang , J. W. Sun , S. H. Jin
DOI: 10.1023/B:PHOT.0000046153.08935.4C
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摘要: Gas exchange, chlorophyll (Chl) fluorescence, and contents of photosynthetic pigments, soluble proteins (ribulose-1,5-bisphosphate carboxylase/oxygenase, RuBPCO), antioxidant enzymes were characterized in the fully expanded 6th leaves rice seedlings grown on either complete (CK) or nitrogen-deficient nutrient (N-deficiency) solutions during a 20-chase period. Compared with control plants, lower capacity at saturation irradiance (Pmax) was accompanied by an increase intercellular CO2 concentration (Ci), indicating that N-deficient plants decline Pmax not due to stomatal limitation but reduced carboxylation efficiency. The fluorescence parameters ΦPS2, Fv′/Fm′, electron transport rate (ETR), qP showed same tendency as plants. Correspondingly, higher qN paralleled rise ratio carotenoid (Car) Chl contents. However, Fv/Fm still diminished, suggesting photoinhibition did occur photosystem 2 (PS2) reaction centres. In addition, activities fresh mass basis gradually lowered, leading aggravation membrane lipid peroxidation proceeding N-deficiency. accumulation malonyldialdehyde resulted lessening protein content. Analyses regression PS2 excitation pressure (1 - qP) linearly correlated content inversely (particularly RuBPCO) There lag phase compared decrease RuBPCO Therefore, increased under N-deficiency is probably result chain use reductants Calvin cycle. Rice responded high decreasing light-harvesting increasing thermal dissipation absorbed energy.